In this project, the operation and the features of a new three-level converter are presented with PV
source and boost converter. The proposed topology was named three-level active-stacked neutral point clamped.
It is a derivative of the 3L-SNPC structure, having two additional active switches connected anti parallel with
the clamp diodes. The main advantage of 3L-ASNPC converter is the reduction of the average switching
frequency for all power devices. In the same time, the apparent switching frequency of the output voltage is
doubled.
This document presents a matrix converter topology for single-phase to three-phase AC power conversion for electric rail traction applications. The converter replaces the conventional multi-stage AC-DC-AC conversion with a single-stage direct AC-AC conversion. The matrix converter operation is analyzed using a separation and link approach, and sinusoidal pulse width modulation control is used. Simulation results show the feasibility of the matrix converter for retrofitting existing AC traction drive systems with a single-stage power conversion topology.
The document discusses the key components of electric power systems, including generator models, transmission line models, transformer models, and load models. Equivalent circuits are used to represent each component for analysis purposes. A single line diagram representation is used to model an entire three-phase power system using a single-phase equivalent circuit. Per-unit normalization is also introduced to simplify calculations involving different voltage bases.
This document presents a single phase to three phase matrix converter topology for electric traction drives. The matrix converter replaces the multiple conversion stages of a conventional AC-DC-AC converter with a single stage direct AC-AC conversion. The converter analysis is presented using a separation and link approach, which treats the converter as two equivalent circuits during the positive and negative periods of the AC source voltage. Sinusoidal pulse width modulation control is used to control the bi-directional switches in the converter in order to obtain the desired three phase output voltage and frequency for driving an induction traction motor. Simulation results indicate this matrix converter is a feasible replacement for the conversion stages in existing AC traction drive systems.
Space Vector Modulation Strategy for NPC ConverterIRJET Journal
This document describes a control strategy for an eight-switch neutral point clamped (NPC) converter. The NPC converter uses only two legs instead of the conventional three legs to reduce the number of switches. A simplified space vector pulse width modulation (SVPWM) algorithm is used to calculate the time durations of the voltage vectors and generate control pulses for the switches. Computer simulations are presented to verify that the control strategy can regulate the DC bus voltage and draw sinusoidal line currents with unity power factor from the AC mains.
Asymmetrical Nine-level Inverter Topology with Reduce Power Semicondutor DevicesTELKOMNIKA JOURNAL
In this paper a new single-phase multilevel inverter topology is presented. Proposed topology is
capable of producing nine-level output voltage with reduce device counts. It can be achieved by arranging
available switches and dc sources in a fashion such that the maximum combination of addition and
subtraction of the input dc sources can be obtained. To verify the viability of the proposed topology, the
circuit model is developed and simulated in Matlab-Simulink software. Experimental testing results of the
proposed nine-level inverter topology, developed in the laboratory, are presented. A low frequency
switching strategy is employed in this work. The results show that the proposed topology is capable to
produce a nine-level output voltage, capable in handling inductive load and yields acceptable harmonic
distortion content.
In this paper, a three-phase load connected to a NPC three-level inverter is presented. To generate gate signals for the multilevel inverter, two commands are developed and compared: the phase disposition pulse width modulation (PDPWM) and the space vector pulse width modulation (SVPWM). DC supply is provided by photovoltaic cells. Boost converter controls the power transfer from photovoltaic generator. Due to nonlinear I-V characteristics of photovoltaic cells, a maximum power point tracking algorithm is adopted to maximize the output power, the nonlinear controller (sliding mode) is developed and simulated. To verify the effectivnesse of the introdueced controller, it is compared with the fuzzy logic controller. Matlab-simulink is used for simulation, analysis and interpretation the results of these controllers.
Analysis of Multilevel Inverter using Bipolar and Unipolar Switching Schemes ...ijsrd.com
Cascaded H-bridge Multilevel Inverter (MLI) is most efficient topology for medium and high voltage DC-AC conversion, having less output harmonics and less commutation losses. Disadvantages are their complexity, more number of power devices, passive components and a complex control circuitry. Here a Cascaded Hybrid Multilevel Inverter is used to produce a three phase 9-level output voltages. Now a day inverter is also know as a DC-AC converter, is one of the most popular part of electrical device. This proposed inverter widely used in industries application such as speed control of induction motor. This thesis focus on three phase 9-level bipolar and unipolar switching inverter with characteristics like output voltage boosting ability and also we discus about the bipolar and unipolar switching scheme along with capacitor voltage control. The modified topology uses Cascaded H-bridge (CHB) with bidirectional and unidirectional switches producing boost up output voltage. Here a hybrid Pulse Width Modulation (PWM) technique is applied to control the power devices. This modulation technique uses a sine wave and a repeating wave, these waves are combined and a complete reference wave is generated. There is comparative study between CHB and modified topology between number of power devices used and Total Harmonic Distortions (THD). THD of modified topology is reduced and analyzed by FFT window. The results are observed by MATLAB/SIMULINK software.
Fuzzy Logic Controller Based High Frequency Link AC-AC Converter For Voltage ...IJTET Journal
Abstract—In this paper, an advanced high frequency link AC-AC Push-pull cycloconverter for the voltage compensation is proposed in order to maintain the power quality in electric grid. The proposed methodology can be achieve arbitrary output voltage without using large energy storage elements. So that the system is more steadfast and less costly compared with the conventional inverter topology. Additionally, the proposed converter does not contain any line frequency transformer, which reduces the cost further. The control scheme for the push pull cycloconverter employs the fuzzy logic controller based sinusoidal pulse width modulation (SPWM) to accomplish better performance on voltage compensation, like unbalanced voltage harmonics elimination. The simulation results are given to show the effectiveness of the proposed high frequency link AC-AC converter and fuzzy logic controller based SPWM technology
This document presents a matrix converter topology for single-phase to three-phase AC power conversion for electric rail traction applications. The converter replaces the conventional multi-stage AC-DC-AC conversion with a single-stage direct AC-AC conversion. The matrix converter operation is analyzed using a separation and link approach, and sinusoidal pulse width modulation control is used. Simulation results show the feasibility of the matrix converter for retrofitting existing AC traction drive systems with a single-stage power conversion topology.
The document discusses the key components of electric power systems, including generator models, transmission line models, transformer models, and load models. Equivalent circuits are used to represent each component for analysis purposes. A single line diagram representation is used to model an entire three-phase power system using a single-phase equivalent circuit. Per-unit normalization is also introduced to simplify calculations involving different voltage bases.
This document presents a single phase to three phase matrix converter topology for electric traction drives. The matrix converter replaces the multiple conversion stages of a conventional AC-DC-AC converter with a single stage direct AC-AC conversion. The converter analysis is presented using a separation and link approach, which treats the converter as two equivalent circuits during the positive and negative periods of the AC source voltage. Sinusoidal pulse width modulation control is used to control the bi-directional switches in the converter in order to obtain the desired three phase output voltage and frequency for driving an induction traction motor. Simulation results indicate this matrix converter is a feasible replacement for the conversion stages in existing AC traction drive systems.
Space Vector Modulation Strategy for NPC ConverterIRJET Journal
This document describes a control strategy for an eight-switch neutral point clamped (NPC) converter. The NPC converter uses only two legs instead of the conventional three legs to reduce the number of switches. A simplified space vector pulse width modulation (SVPWM) algorithm is used to calculate the time durations of the voltage vectors and generate control pulses for the switches. Computer simulations are presented to verify that the control strategy can regulate the DC bus voltage and draw sinusoidal line currents with unity power factor from the AC mains.
Asymmetrical Nine-level Inverter Topology with Reduce Power Semicondutor DevicesTELKOMNIKA JOURNAL
In this paper a new single-phase multilevel inverter topology is presented. Proposed topology is
capable of producing nine-level output voltage with reduce device counts. It can be achieved by arranging
available switches and dc sources in a fashion such that the maximum combination of addition and
subtraction of the input dc sources can be obtained. To verify the viability of the proposed topology, the
circuit model is developed and simulated in Matlab-Simulink software. Experimental testing results of the
proposed nine-level inverter topology, developed in the laboratory, are presented. A low frequency
switching strategy is employed in this work. The results show that the proposed topology is capable to
produce a nine-level output voltage, capable in handling inductive load and yields acceptable harmonic
distortion content.
In this paper, a three-phase load connected to a NPC three-level inverter is presented. To generate gate signals for the multilevel inverter, two commands are developed and compared: the phase disposition pulse width modulation (PDPWM) and the space vector pulse width modulation (SVPWM). DC supply is provided by photovoltaic cells. Boost converter controls the power transfer from photovoltaic generator. Due to nonlinear I-V characteristics of photovoltaic cells, a maximum power point tracking algorithm is adopted to maximize the output power, the nonlinear controller (sliding mode) is developed and simulated. To verify the effectivnesse of the introdueced controller, it is compared with the fuzzy logic controller. Matlab-simulink is used for simulation, analysis and interpretation the results of these controllers.
Analysis of Multilevel Inverter using Bipolar and Unipolar Switching Schemes ...ijsrd.com
Cascaded H-bridge Multilevel Inverter (MLI) is most efficient topology for medium and high voltage DC-AC conversion, having less output harmonics and less commutation losses. Disadvantages are their complexity, more number of power devices, passive components and a complex control circuitry. Here a Cascaded Hybrid Multilevel Inverter is used to produce a three phase 9-level output voltages. Now a day inverter is also know as a DC-AC converter, is one of the most popular part of electrical device. This proposed inverter widely used in industries application such as speed control of induction motor. This thesis focus on three phase 9-level bipolar and unipolar switching inverter with characteristics like output voltage boosting ability and also we discus about the bipolar and unipolar switching scheme along with capacitor voltage control. The modified topology uses Cascaded H-bridge (CHB) with bidirectional and unidirectional switches producing boost up output voltage. Here a hybrid Pulse Width Modulation (PWM) technique is applied to control the power devices. This modulation technique uses a sine wave and a repeating wave, these waves are combined and a complete reference wave is generated. There is comparative study between CHB and modified topology between number of power devices used and Total Harmonic Distortions (THD). THD of modified topology is reduced and analyzed by FFT window. The results are observed by MATLAB/SIMULINK software.
Fuzzy Logic Controller Based High Frequency Link AC-AC Converter For Voltage ...IJTET Journal
Abstract—In this paper, an advanced high frequency link AC-AC Push-pull cycloconverter for the voltage compensation is proposed in order to maintain the power quality in electric grid. The proposed methodology can be achieve arbitrary output voltage without using large energy storage elements. So that the system is more steadfast and less costly compared with the conventional inverter topology. Additionally, the proposed converter does not contain any line frequency transformer, which reduces the cost further. The control scheme for the push pull cycloconverter employs the fuzzy logic controller based sinusoidal pulse width modulation (SPWM) to accomplish better performance on voltage compensation, like unbalanced voltage harmonics elimination. The simulation results are given to show the effectiveness of the proposed high frequency link AC-AC converter and fuzzy logic controller based SPWM technology
This document presents a dynamic model of a permanent magnet synchronous motor. It derives a two-phase d-q model from the three-phase model by transforming the stator variables from the stationary a-b-c frame to the rotating d-q frame. It discusses obtaining the complete set of model parameters from simple laboratory tests, as some parameters are not directly measurable and vary with operating conditions. The model is primarily for interior permanent magnet synchronous motors but can also apply to surface permanent magnet motors.
Control And Programingof Synchronous Generatorfreelay
author: International Team
publisher: Daniel Garrido
licence: Creative Commons
place: University of Southern Denmark- Odense
@fomenting colaborational knowledge
Application of SVM Technique for Three Phase Three Leg Ac/Ac Converter TopologyIOSR Journals
This paper presents a simulation of a three-phase three-leg AC/AC converter topology using nine IGBTs and space vector pulse width modulation (SVM) technique. The proposed topology reduces the number of switches compared to conventional back-to-back and matrix converters. Simulation results show the converter provides sinusoidal input and output voltages with unity power factor under constant frequency and variable frequency operation. Experimental results from a 5kVA prototype verify the validity of the proposed scheme.
To overcome the problem of mismatched voltage levels between parallel-connected low voltage photovoltaic (PV)
arrays and the higher grid voltage, a hybrid boost three level dc-dc converter is developed based on three level inverter with
the traditional single phase diode clamping. Only one inductor, two capacitors in series, and those power switches and diodes,
which are easy to be integrated, are used for establish the topology with transformerless high voltage gain. The operation
principle of the topology is analyzed, and then the pulse width modulation (PWM) control method is obtained according to
the switching functions about the output pulse voltages of both half-bridges. Therefore, the converter can not only operate
with high voltage gain, but also make the duty cycles of power switches closer to 0.5. A feedforward closed loop control
operation is proposed such that even in varying input the converter is capable of giving a constant output. Finally an
experimental is set up in the laboratory for open loop control operation. All experimental results verify the feasibility of the
circuit and validity of the PWM control method.
Torque Ripple Minimization of a BLDC Motor Drive by Using Electronic Commutat...AI Publications
Brushless DC motors are having a major problem with harmonics in torque. The variations in speed and production of noise should be minimized by using proper topologies. BLDC motors have been gaining attention from different Industrial and domestic appliance manufacturers, because of their high efficiency, high power density and easy maintenance and low cost. This paper presents a three phase BLDC motor with low cost drive to be driven without DC link capacitor. The proposed technique uses an electronic commutation and operates the machine exclusive of the intermediate DC link capacitor. The designing of Brushless DC motor drive system along with control system for torque ripple minimization, speed controller and current controllers are presented using MATLAB / SIMULINK and results are evaluated.
Total Harmonic Distortion of Dodecagonal Space Vector ModulationIJPEDS-IAES
Space vector modulation technique is one of the best PWM techniques which have been implemented to the Multilevel inverter circuit to get the purely sinusoidal cuurent. This is a important algorithm which is implemented in open wind induction motor. This type of I.M has great impact on Electric Drive system. SVM is nothing but the technique of switching algorithm. The Hexagonal space vector modulation has been implemented before, but elimination of higher order harmonics is not possible. Torque pulsation arises. Speed control of Induction motor was not smooth. So Dodecagonal (12) structure developed. A 12 side polygonal space vector structure is meant for eliminating (6n±1) harmonics in the phase current waveform throughout the modulating range. A high resolution of PWM technique is proposed involving multiple 12 sided polygonal (Dodecagonal) structure that can generate highly sinusoidal voltage at a reduced switching frequency. In this paper different values of frequencies have been taken for harmonic analysis. SVM method features a higher level of dc-bus voltage utilization compared to the conventional PWM.
discusses about the reduction of commutation torque ripple in BLDC motor and various convention methods and the proposed method for 2 level inverter and 3 level inverter
Development of a Novel Three Phase Grid-Tied Multilevel Inverter TopologyIAES-IJPEDS
The conventional line-commutated ac-to-dc converters/ inverters have square-shaped line current. It contains higher-order harmonics which generates EMI and it causes more heating of the core of distribution or power transformers. PWM based inverters using MOSFET/IGBT have higher switching losses, and the power handling capability and reliability are quite low in comparison to thyristors/ SCR. A thyristor based forced commutated inverters are not suitable for PWM applications due to the problems of commutation circuits. A pure sinusoidal voltage output or waveform with low harmonic contents is most desirable for ac load using dc to ac conversion. This paper presents a new multilevel inverter topology in which three phase ac- to-dc converter circuits are used in inversion mode by controlling the switching angle. Due to natural commutation, no separate circuit is required for synchronization. In this paper simulation and analysis are done for grid-tied three-phase 6-pulse, Two three-phase, 3-pulse and 12-pulse converter. These converters are analysed for different battery voltage and different switching angle combinations in order to reduce the total harmonic distortion (THD). Three-phase harmonic filters are further added to the grid side to reduce the harmonic content in the line current. A comparative study of these converters is also presented in this paper.
This document presents a comparative study of the effects of GCSC (GTO Controlled Series Capacitor) and TCSC (Thyristor Controlled Series Capacitor) on the setting zones of a distance relay protecting a 400 kV transmission line in Algeria. It investigates the modified setting of the forward zones (Z1, Z2, Z3) and reverse zone (Z4) with GCSC and TCSC in capacitive and inductive modes at different firing angles. The study is performed using MATLAB software. Distance relays measure impedance by calculating the ratio of voltage to current. The presence of FACTS devices influences the total impedance seen by the relay, requiring zone settings to be modified to
H6 Transformer less Topology and Its Modulation Strategy for Mitigating Cm Cu...IJERA Editor
MATLABbasedsingle-phase three-level topology for a transformer less photovoltaic system is presented in this paper. Compared with the conventional H-bridge topology, it only needs two additional asymmetrically distributed switches, and the system common-mode voltage can be kept constant with a simple modulation scheme. Family of H6 transformer less inverter topologies with low leakage currents is proposed and highly efficient and reliable inverter concept (HERIC) topology is also presented in this paper. The proposed inverter can also operate with high frequency by retaining high efficiency which enables reduced cooling system. Finally, the proposed new topology is simulated by MATLAB/Simulink software to validate the accuracy of the theoretical explanation.
This document provides a summary of key concepts from Chapter 2 on AC circuits. It discusses instantaneous, average, and active power calculations. It defines reactive power as the oscillating component of instantaneous power. It examines power calculations for resistive, inductive, and capacitive circuits. Power triangles and complex power are introduced. Power factor correction methods are described. Complex power flow between buses is discussed. Key concepts for three-phase circuits like phase sequence, line voltages, and per-phase analysis are covered. Formulas are provided for calculating real, reactive, and complex power in balanced three-phase systems.
A Novel Control Strategy of Indirect Matrix Converter Using Space Vector Modu...IJPEDS-IAES
This document presents a novel control strategy for an indirect matrix converter using space vector modulation. The control strategy aims to stabilize frequency variations. It was implemented in MATLAB/Simulink and showed better performance than conventional techniques with lower THD, higher output voltage at the same modulation index, lower switching stress and losses. The complete control strategy including DC link formation, commutation scheme, dwell time calculation and simulation results validating the theoretical analysis are described in the document.
This document summarizes key concepts about three-phase systems. It defines a three-phase system as having three sinusoidal voltages differing in phase by 120 degrees. The voltages can form a positive or negative sequence. Three-phase systems are commonly used for power generation, transmission, and distribution due to their ability to transmit more power with less material. Formulas are provided for calculating line voltages, currents, and power in balanced and unbalanced three-phase systems. Advantages of three-phase systems like constant torque and easier starting of motors are also discussed.
Four switch three phase brushless dc motor drive for hybrid vehiclesIAEME Publication
This document summarizes a paper that proposes a four-switch brushless DC motor drive for hybrid electric vehicles. It introduces a two-input DC-DC boost converter that interfaces a photovoltaic power source and battery for energy storage. The boost converter supplies regulated voltage to a four-switch BLDC motor drive for direct current control. Speed limitation is typically an issue for four-switch topologies but is addressed by regulating the boost converter output voltage according to motor speed. The document outlines the operating modes, current regulation, and back EMF compensation strategy of the four-switch drive as well as the speed limitation challenge it aims to solve.
This document discusses the development and structure of the Swedish power system. It began with hydroelectric power stations and later added coal and nuclear power plants. A 220-400kV transmission system was developed to transmit power from northern hydroelectric sources to industrial areas in the south and middle of Sweden. Today the system includes high voltage transmission lines, transformers and substations connecting large centralized power plants ranging from 1000MW to individual consumer needs of kW. The main sources of electricity in Sweden are now hydroelectric, nuclear and some combined heat and power, with hydro and nuclear providing most generation.
This paper presents a phase shifted series resonant converter with step up high frequency transformer to achieve the functions of high output voltage, high power density and wide range of Zero Voltage Switching (ZVS). In this approach, the output voltage is controlled by varying the switching frequency. The controller has been designed to achieve a good stability under different load conditions. The converter will react to the load variation by varying its switching frequency to satisfy the output voltage requirements. Therefore in order to maintain constant output voltage, for light load (50% of the load), the switching frequency will be decreased to meet the desired output, while for the full load (100%) conditions, the switching frequency will be increased. Since the controlled switching frequency is limited by the range between the higher and lower resonant frequencies , the switches can be turned on under ZVS. In this study, a laboratory experiment has been conducted to verify the effectiveness of the system performance.
Power systems can be modeled and analyzed using per-unit representations of components. Key models include:
1) Generator models that specify real and reactive power injection or terminal voltage and current.
2) Transformer models using an equivalent circuit with magnetizing reactance and resistance.
3) Load models like constant impedance, current, or power to represent different load characteristics.
4) Transmission lines modeled as series impedances.
The per-unit system allows analysis of different voltage levels on a common scale and simplifies modeling of components.
The document discusses power flow analysis, which determines bus voltages and power flows in a power system under normal steady-state operating conditions. It provides the mathematical formulation of the power flow problem as a set of nonlinear algebraic equations that must be solved iteratively. Buses are classified as slack, generator, or load buses depending on which two of four associated quantities - real power, reactive power, voltage magnitude, and voltage angle - are specified versus solved for. Solution methods like the Gauss-Seidel method are commonly used to iteratively solve the power flow equations until bus voltages converge.
This document contains an exam paper for the subject Power System I (EEE 305). It has two sections with multiple choice and descriptive questions. Section A contains questions related to power system modeling, symmetrical components, transmission lines and fault analysis. Section B contains questions on load flow analysis, transmission lines, and power flow control. The paper tests students' understanding of fundamental power system concepts and their ability to analyze common power system problems.
SVM-plus-Phase-Shift Modulation Strategy for Single-Stage.pdfgulie
This document proposes a new modulation strategy called SVM-plus-phase-shift (SVM-PS) modulation for a single-stage three-phase resonant AC-DC matrix converter with an LCL resonant tank. The strategy aims to achieve unity power factor and flexible control of active and reactive power transfer. It derives the relationship between switch states and line-frequency phase currents based on the fundamental component of the tank current. This allows simple control of current amplitude and phase via modulation of the AC and DC side switches based on voltage and current references. Simulation results show the proposed strategy reduces current distortion and ripple compared to conventional SVM.
This document proposes and analyzes a reversible three-phase switching mode rectifier consisting of four active switches. It derives a closed-form pulse width modulation duty cycle control law to achieve sinusoidal input currents, controllable power factor, bidirectional power flow capability, and adjustable DC output voltage without using current sensors. The rectifier is modeled using state space averaging techniques and space vector representation. Both steady-state and small signal analyses are performed. Experimental results demonstrate the rectifier achieves the desired properties and bidirectional power flow. Guidelines for determining component parameters and controller gains are also described.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
This document presents a dynamic model of a permanent magnet synchronous motor. It derives a two-phase d-q model from the three-phase model by transforming the stator variables from the stationary a-b-c frame to the rotating d-q frame. It discusses obtaining the complete set of model parameters from simple laboratory tests, as some parameters are not directly measurable and vary with operating conditions. The model is primarily for interior permanent magnet synchronous motors but can also apply to surface permanent magnet motors.
Control And Programingof Synchronous Generatorfreelay
author: International Team
publisher: Daniel Garrido
licence: Creative Commons
place: University of Southern Denmark- Odense
@fomenting colaborational knowledge
Application of SVM Technique for Three Phase Three Leg Ac/Ac Converter TopologyIOSR Journals
This paper presents a simulation of a three-phase three-leg AC/AC converter topology using nine IGBTs and space vector pulse width modulation (SVM) technique. The proposed topology reduces the number of switches compared to conventional back-to-back and matrix converters. Simulation results show the converter provides sinusoidal input and output voltages with unity power factor under constant frequency and variable frequency operation. Experimental results from a 5kVA prototype verify the validity of the proposed scheme.
To overcome the problem of mismatched voltage levels between parallel-connected low voltage photovoltaic (PV)
arrays and the higher grid voltage, a hybrid boost three level dc-dc converter is developed based on three level inverter with
the traditional single phase diode clamping. Only one inductor, two capacitors in series, and those power switches and diodes,
which are easy to be integrated, are used for establish the topology with transformerless high voltage gain. The operation
principle of the topology is analyzed, and then the pulse width modulation (PWM) control method is obtained according to
the switching functions about the output pulse voltages of both half-bridges. Therefore, the converter can not only operate
with high voltage gain, but also make the duty cycles of power switches closer to 0.5. A feedforward closed loop control
operation is proposed such that even in varying input the converter is capable of giving a constant output. Finally an
experimental is set up in the laboratory for open loop control operation. All experimental results verify the feasibility of the
circuit and validity of the PWM control method.
Torque Ripple Minimization of a BLDC Motor Drive by Using Electronic Commutat...AI Publications
Brushless DC motors are having a major problem with harmonics in torque. The variations in speed and production of noise should be minimized by using proper topologies. BLDC motors have been gaining attention from different Industrial and domestic appliance manufacturers, because of their high efficiency, high power density and easy maintenance and low cost. This paper presents a three phase BLDC motor with low cost drive to be driven without DC link capacitor. The proposed technique uses an electronic commutation and operates the machine exclusive of the intermediate DC link capacitor. The designing of Brushless DC motor drive system along with control system for torque ripple minimization, speed controller and current controllers are presented using MATLAB / SIMULINK and results are evaluated.
Total Harmonic Distortion of Dodecagonal Space Vector ModulationIJPEDS-IAES
Space vector modulation technique is one of the best PWM techniques which have been implemented to the Multilevel inverter circuit to get the purely sinusoidal cuurent. This is a important algorithm which is implemented in open wind induction motor. This type of I.M has great impact on Electric Drive system. SVM is nothing but the technique of switching algorithm. The Hexagonal space vector modulation has been implemented before, but elimination of higher order harmonics is not possible. Torque pulsation arises. Speed control of Induction motor was not smooth. So Dodecagonal (12) structure developed. A 12 side polygonal space vector structure is meant for eliminating (6n±1) harmonics in the phase current waveform throughout the modulating range. A high resolution of PWM technique is proposed involving multiple 12 sided polygonal (Dodecagonal) structure that can generate highly sinusoidal voltage at a reduced switching frequency. In this paper different values of frequencies have been taken for harmonic analysis. SVM method features a higher level of dc-bus voltage utilization compared to the conventional PWM.
discusses about the reduction of commutation torque ripple in BLDC motor and various convention methods and the proposed method for 2 level inverter and 3 level inverter
Development of a Novel Three Phase Grid-Tied Multilevel Inverter TopologyIAES-IJPEDS
The conventional line-commutated ac-to-dc converters/ inverters have square-shaped line current. It contains higher-order harmonics which generates EMI and it causes more heating of the core of distribution or power transformers. PWM based inverters using MOSFET/IGBT have higher switching losses, and the power handling capability and reliability are quite low in comparison to thyristors/ SCR. A thyristor based forced commutated inverters are not suitable for PWM applications due to the problems of commutation circuits. A pure sinusoidal voltage output or waveform with low harmonic contents is most desirable for ac load using dc to ac conversion. This paper presents a new multilevel inverter topology in which three phase ac- to-dc converter circuits are used in inversion mode by controlling the switching angle. Due to natural commutation, no separate circuit is required for synchronization. In this paper simulation and analysis are done for grid-tied three-phase 6-pulse, Two three-phase, 3-pulse and 12-pulse converter. These converters are analysed for different battery voltage and different switching angle combinations in order to reduce the total harmonic distortion (THD). Three-phase harmonic filters are further added to the grid side to reduce the harmonic content in the line current. A comparative study of these converters is also presented in this paper.
This document presents a comparative study of the effects of GCSC (GTO Controlled Series Capacitor) and TCSC (Thyristor Controlled Series Capacitor) on the setting zones of a distance relay protecting a 400 kV transmission line in Algeria. It investigates the modified setting of the forward zones (Z1, Z2, Z3) and reverse zone (Z4) with GCSC and TCSC in capacitive and inductive modes at different firing angles. The study is performed using MATLAB software. Distance relays measure impedance by calculating the ratio of voltage to current. The presence of FACTS devices influences the total impedance seen by the relay, requiring zone settings to be modified to
H6 Transformer less Topology and Its Modulation Strategy for Mitigating Cm Cu...IJERA Editor
MATLABbasedsingle-phase three-level topology for a transformer less photovoltaic system is presented in this paper. Compared with the conventional H-bridge topology, it only needs two additional asymmetrically distributed switches, and the system common-mode voltage can be kept constant with a simple modulation scheme. Family of H6 transformer less inverter topologies with low leakage currents is proposed and highly efficient and reliable inverter concept (HERIC) topology is also presented in this paper. The proposed inverter can also operate with high frequency by retaining high efficiency which enables reduced cooling system. Finally, the proposed new topology is simulated by MATLAB/Simulink software to validate the accuracy of the theoretical explanation.
This document provides a summary of key concepts from Chapter 2 on AC circuits. It discusses instantaneous, average, and active power calculations. It defines reactive power as the oscillating component of instantaneous power. It examines power calculations for resistive, inductive, and capacitive circuits. Power triangles and complex power are introduced. Power factor correction methods are described. Complex power flow between buses is discussed. Key concepts for three-phase circuits like phase sequence, line voltages, and per-phase analysis are covered. Formulas are provided for calculating real, reactive, and complex power in balanced three-phase systems.
A Novel Control Strategy of Indirect Matrix Converter Using Space Vector Modu...IJPEDS-IAES
This document presents a novel control strategy for an indirect matrix converter using space vector modulation. The control strategy aims to stabilize frequency variations. It was implemented in MATLAB/Simulink and showed better performance than conventional techniques with lower THD, higher output voltage at the same modulation index, lower switching stress and losses. The complete control strategy including DC link formation, commutation scheme, dwell time calculation and simulation results validating the theoretical analysis are described in the document.
This document summarizes key concepts about three-phase systems. It defines a three-phase system as having three sinusoidal voltages differing in phase by 120 degrees. The voltages can form a positive or negative sequence. Three-phase systems are commonly used for power generation, transmission, and distribution due to their ability to transmit more power with less material. Formulas are provided for calculating line voltages, currents, and power in balanced and unbalanced three-phase systems. Advantages of three-phase systems like constant torque and easier starting of motors are also discussed.
Four switch three phase brushless dc motor drive for hybrid vehiclesIAEME Publication
This document summarizes a paper that proposes a four-switch brushless DC motor drive for hybrid electric vehicles. It introduces a two-input DC-DC boost converter that interfaces a photovoltaic power source and battery for energy storage. The boost converter supplies regulated voltage to a four-switch BLDC motor drive for direct current control. Speed limitation is typically an issue for four-switch topologies but is addressed by regulating the boost converter output voltage according to motor speed. The document outlines the operating modes, current regulation, and back EMF compensation strategy of the four-switch drive as well as the speed limitation challenge it aims to solve.
This document discusses the development and structure of the Swedish power system. It began with hydroelectric power stations and later added coal and nuclear power plants. A 220-400kV transmission system was developed to transmit power from northern hydroelectric sources to industrial areas in the south and middle of Sweden. Today the system includes high voltage transmission lines, transformers and substations connecting large centralized power plants ranging from 1000MW to individual consumer needs of kW. The main sources of electricity in Sweden are now hydroelectric, nuclear and some combined heat and power, with hydro and nuclear providing most generation.
This paper presents a phase shifted series resonant converter with step up high frequency transformer to achieve the functions of high output voltage, high power density and wide range of Zero Voltage Switching (ZVS). In this approach, the output voltage is controlled by varying the switching frequency. The controller has been designed to achieve a good stability under different load conditions. The converter will react to the load variation by varying its switching frequency to satisfy the output voltage requirements. Therefore in order to maintain constant output voltage, for light load (50% of the load), the switching frequency will be decreased to meet the desired output, while for the full load (100%) conditions, the switching frequency will be increased. Since the controlled switching frequency is limited by the range between the higher and lower resonant frequencies , the switches can be turned on under ZVS. In this study, a laboratory experiment has been conducted to verify the effectiveness of the system performance.
Power systems can be modeled and analyzed using per-unit representations of components. Key models include:
1) Generator models that specify real and reactive power injection or terminal voltage and current.
2) Transformer models using an equivalent circuit with magnetizing reactance and resistance.
3) Load models like constant impedance, current, or power to represent different load characteristics.
4) Transmission lines modeled as series impedances.
The per-unit system allows analysis of different voltage levels on a common scale and simplifies modeling of components.
The document discusses power flow analysis, which determines bus voltages and power flows in a power system under normal steady-state operating conditions. It provides the mathematical formulation of the power flow problem as a set of nonlinear algebraic equations that must be solved iteratively. Buses are classified as slack, generator, or load buses depending on which two of four associated quantities - real power, reactive power, voltage magnitude, and voltage angle - are specified versus solved for. Solution methods like the Gauss-Seidel method are commonly used to iteratively solve the power flow equations until bus voltages converge.
This document contains an exam paper for the subject Power System I (EEE 305). It has two sections with multiple choice and descriptive questions. Section A contains questions related to power system modeling, symmetrical components, transmission lines and fault analysis. Section B contains questions on load flow analysis, transmission lines, and power flow control. The paper tests students' understanding of fundamental power system concepts and their ability to analyze common power system problems.
SVM-plus-Phase-Shift Modulation Strategy for Single-Stage.pdfgulie
This document proposes a new modulation strategy called SVM-plus-phase-shift (SVM-PS) modulation for a single-stage three-phase resonant AC-DC matrix converter with an LCL resonant tank. The strategy aims to achieve unity power factor and flexible control of active and reactive power transfer. It derives the relationship between switch states and line-frequency phase currents based on the fundamental component of the tank current. This allows simple control of current amplitude and phase via modulation of the AC and DC side switches based on voltage and current references. Simulation results show the proposed strategy reduces current distortion and ripple compared to conventional SVM.
This document proposes and analyzes a reversible three-phase switching mode rectifier consisting of four active switches. It derives a closed-form pulse width modulation duty cycle control law to achieve sinusoidal input currents, controllable power factor, bidirectional power flow capability, and adjustable DC output voltage without using current sensors. The rectifier is modeled using state space averaging techniques and space vector representation. Both steady-state and small signal analyses are performed. Experimental results demonstrate the rectifier achieves the desired properties and bidirectional power flow. Guidelines for determining component parameters and controller gains are also described.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Analysis of the Performance of Active Type SFCL and FCL for Reduction Capabil...IJSRD
The Active Superconducting Current Controller (ASCC) is a new type of Fault Current Limiters which can limit the fault current in different modes and also has the particular abilities of compensating active and reactive power for AC main circuit in the normal state. The use of the ASCC disturbs the operation of Over Current Relays (OCR) used in the distribution system. In consideration that applying superconducting fault current limiter (SFCL) may be a feasible solution, in this paper, the effects of a voltage compensation type active SFCL. The magnetic field in the air core can be controlled by PWM inverter output. Hence, the equivalent impedance can be maintained and overvoltage suppression is possible. The fault current and voltage suppression characteristics are simulated in mat lab. The simulation results show that the active SFCL and FCL can play an obvious role in restraining the fault current and overvoltage, and it can contribute to avoiding damage on the relevant distribution equipment and improve the systems safety and reliability.
A Comparison Between Two Average Modelling Techniques of AC-AC Power ConvertersIAES-IJPEDS
In this paper, a comparative evaluation of two modelling tools for switching AC-AC power converters is presented. Both of them are based on average modelling techniques. The first approach is based on the circuit averaging technique and consists in the topological manipulations, applied to a converter states. The second approach makes use of a state-space averaged model of the converter and is based on analytical manipulations using the different state representations of a converter. The two modelling techniques are applied to a same AC-AC called matrix-reactance frequency converter based on buck-boost topology. These techniques are compared on the basis of their rapidity, quantity of calculations and transformations and its limitations.
Wind power stations, many located in remote areas; so they are characterized by weak grids and are often submitted to power system disturbance like faults. In this paper, the behaviour of a wind energy conversion system that uses the control of the rotor side converter (RSC) by three different methods under faulty conditions is presented. The behaviour of these systems during a grid failure is an important issue. DFIG is analysed and simulated under differing faulty conditions in the environment of MATLAB/SIMULINK. Simulation results show that the proposed method has proper operation during fault conditions.
Variable Voltage Source Equivalent Model of Modular Multilevel ConverterIJRES Journal
The structures of modular multilevel converter module (MMC) are very complex, and the
numerous sub-modules and output level number bring difficulties for the analysis and simulation. In this paper,
assuming the sub-capacitor voltage instantaneous value of a single arm is the same value, the switching
frequency of the switch is much higher than the output voltage frequency, the system harmonics were ignored,
the system state equations are deduced about the intermediate variables as circulation current and the capacitor
voltage between the upper and lower arms. On this basis, a variable voltage source continuous equivalent
model is proposed, which may replace the system physical simulation model with the actual simulation study. At
the same time, the model reflects the relationship between the output voltage and circulation current,which
provide a way to analyze the formation mechanism of circulation and the capacitor voltage fluctuations, and
make system analysis simple and intuitive. The simulation results validate that this continuous model is
rationality and correctness.
A Three Level Single Stage PFC Converter for Variable Power Applicationspaperpublications3
Abstract: AC/DC power converters are required to operate with high power factor (PF) and low total harmonic distortion (THD) for improved grid quality and full capacity utilization of the transmission lines. Passive PF correction (PFC) circuits consist of inductive and capacitive filters followed by a diode bridge. They provide the simplest way of achieving high PF with high efficiency; however, they require low line frequency filters which are bulky and heavy. This work presents a new single stage three level isolated AC/DC PFC converter for high DC link voltage low-power applications achieved through an effective integration of AC/DC and DC/DC stages where all of the switches are shared between two operations. With the converter and switching scheme, input current shaping and output voltage regulation can be achieved simultaneously without introducing additional switches or switching actions. Due to the flexible DC link voltage structure, high power factor can be achieved at high line voltage. The performance of the single stage PFC converter is simulated in MATLAB/SIMULINK environment.
Keywords: Power Factor (PF), DC Link Voltage, Power Factor Correction Circuits (PFC).
Title: A Three Level Single Stage PFC Converter for Variable Power Applications
Author: Litty Joseph, Prof. Neetha John, Prof. Emmanuel Babu P
ISSN 2349-7815
International Journal of Recent Research in Electrical and Electronics Engineering (IJRREEE)
Paper Publications
International Journal of Engineering Research and DevelopmentIJERD Editor
This document describes a novel bidirectional DC-DC converter that can provide high step-up and step-down voltage gains. It utilizes a coupled inductor with the same number of turns in the primary and secondary windings to achieve these high voltage gains. The steady-state analysis and operating principles of the converter in continuous conduction mode are presented. Simulations in MATLAB are used to verify the performance of the proposed converter and show it can provide constant output voltage when feedback is applied. Compared to a conventional bidirectional DC-DC converter, the proposed design offers higher voltage conversion ratios in both step-up and step-down modes of operation.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
[9] a systematic parameter tuning of pi current controller for lcl type activ...Ngoc Dinh
Phuong Vu, Nam Hoang, Ngoc Nguyen, Quan Nguyen, Minh Tran;”A systematic parameter tuning of PI current controller for LCL-type active rectifiers under unbalanced grid voltage conditions”; Journal of Electrical Systems.
A three-phase bidirectional isolated dc-dc converter consists of two six-pulse two-level active converters that enable bidirectional power flow by introducing a lag phase-shift angle of one converter with respect to the other converter. This paper explains the operating modes of a three-phase bidirectional isolated dc-dc converter in detail, taking into account the transfer of energy between the dc voltage sources and high-frequency ac inductances in the three-phase bidirectional isolated dc-dc converter. The power flow of the dc-dc converter is also examined based on the operating modes.
This paper provides a new approach to reducing high-order harmonics in 400 Hz inverter using a three-level neutral-point clamped (NPC) converter. A voltage control loop using the harmonic compensation combined with NPC clamping diode control technology. The capacitor voltage imbalance also causes harmonics in the output voltage. For 400 Hz inverter, maintain a balanced voltage between the two input (direct current) (DC) capacitors is difficult because the pulse width modulation (PWM) modulation frequency ratio is low compared to the frequency of the output voltage. A method of determining the current flowing into the capacitor to control the voltage on the two balanced capacitors to ensure fast response reversal is also given in this paper. The combination of a high-harmonic resonator controller and a neutral-point voltage controller working together on the 400 Hz NPC inverter structure is given in this paper.
A Single-Stage High-Frequency Isolated Secondary- Side Controlled AC-DC Conve...IDES Editor
This paper presents a new single-stage highfrequency
isolated ac-dc converter that uses a simple control
circuit. It is well suitable for wide input variation power
sources. The circuit configuration combines a diode rectifier,
boost converter and half-bridge dc-dc resonant converter. A
high power factor is achieved by discontinuous current mode
(DCM) operation of the front-end integrated power factor
correction circuit. The output voltage is regulated by fixedfrequency,
secondary-side phase-shift active rectifier. Softswitching
operation is achieved for all the switches. This
converter operates in three modes, which is classified
according to conduction of different switches and diodes. The
intervals of operation and steady-state analysis are presented
in detail. Design example of a 100 W proposed converter is
given together with its simulation and experiment results for
wide variation in input voltage.
- The document describes a cyclo-converter, which converts AC voltage at the supply frequency directly to AC voltage at the load frequency without an intermediate DC stage.
- It discusses the basic principle of operation using an equivalent circuit model and voltage waveforms for loads with different displacement angles.
- The circuit of a single-phase to single-phase cyclo-converter using thyristor bridges is presented. Its operation is explained for resistive and inductive loads in both continuous and discontinuous current modes. Waveforms show how the firing angles are varied to synthesize the output voltage.
- Cyclo-converters allow output frequencies up to about one-third of the supply frequency and operate with loads of any phase angle.
This paper presents a comprehensive and systematic approach in developing a new switching look-up table for direct power control (DPC) strategy applied to the three-phase grid connected three-level neutral-point clamped (3L-NPC) pulse width modulated (PWM) rectifier. The term of PWM rectifier used in this paper is also known as AC-DC converter. The approach provides detailed information regarding the effects of each multilevel converter space vector to the distribution of input active and reactive power in the converter system. Thus, the most optimal converter space vectors are able to be selected by the switching look-up table, allowing smooth control of the active and reactive powers for each sector. In addition, the proposed DPC utilizes an NPC capacitor balanced strategy to enhance the performance of front-end AC-DC converter during load and supply voltage disturbances. The steady state as well as the dynamic performances of the proposed DPC are presented and analyzed by using MATLAB/Simulink software. The results show that the AC-DC converter utilizing the new look-up table is able to produce almost sinusoidal line currents with lower current total harmonic distortion, unity power factor operation, adjustable DC-link output voltage and good dynamic response during load disturbance.
SIMULATION ANALYSIS OF CLOSED LOOP DUAL INDUCTOR CURRENT-FED PUSH-PULL CONVER...Journal For Research
The current electronic devices require DC power source, which is taken from a battery or DC power supply. DC-DC converter is utilized to get regulated dc voltage from unregulated one. Switched mode power supply (SMPS) are commonly used in industrial applications, because of more advantages compared to linear power supply. In SMPS we have isolated and non-isolated converters, where isolated converters are frequently used, in order to get more voltage with multiple outputs. So among different isolated converters, push-pull converter is chosen for micro converter applications to obtain high voltage conversion ratio by using HF transformer, due to their better utilization of transformer. New methodology of control is implemented for making ZVS and ZCS at same time and to reduce the number of switches in the secondary side of dual inductor CFPP converter, which is a voltage doubler circuit. This becomes the solution for problem identification. Thus this converter with soft-switching reduces the switching losses.The current-fed push-pull converters are used in many applications like photo-voltaic (PV) power converters for boosting the output voltage. Push-pull converter is chosen for micro converter applications, to obtain high voltage conversion ratio by using high frequency (HF) transformer, due to their better utilization of transformer. This deals with the design of dual inductor CFPP converter, where zero voltage switching (ZVS) and zero current switching (ZCS) is achieved for the primary side of the converter by using secondary switches. Primary side switches are controlled by closed loop control topology. The secondary side is made with voltage doubler to obtain high voltage. Open loop and closed loop control of dual inductor current fed push pull converter simulation is finished by MATLAB/SIMULINK and their outcomes are analyzed.
The study made in this paper concerns the use of the voltage-oriented control (VOC) of three-phase pulse width modulation (PWM) rectifier with constant switching frequency. This control method, called voltage-oriented controlwith space vector modulation (VOC-SVM). The proposed control scheme has been founded on the transformation between stationary (α-β) and and synchronously rotating (d-q) coordinate system, it is based on two cascaded control loops so that a fast inner loop controls the grid current and an external loop DC-link voltage, while the DC-bus voltage is maintained at the desired level and ansured the unity power factor operation. So, the stable state performance and robustness against the load’s disturbance of PWM rectifiers are boths improved. The proposed scheme has been implemented and simulated in MATLAB/Simulink environment. The control system of the VOC-SVM strategy has been built based on dSPACE system with DS1104 controller board. The results obtained show the validity of the model and its control method. Compared with the conventional SPWM method, the VOC-SVM ensures high performance and fast transient response.
Analysis of Modulation Strategies for Two-Stage Interleaved Voltage Source In...IJARBEST JOURNAL
This paper deals with the investigation of interleaved voltage source inverter for
photovoltaic applications. This topology focuses on the reduction of inductor current ripple
content, total harmonic distortion (THD) of the proposed topology. In addition, the filter size is
reduced when compared to single-stage voltage source inverter. The design of filter for the
proposed topology is highlighted. The paper discusses the different modulation strategies for the
proposed topology with different values of modulation index. A comparison made between the
different strategies is reported. And comparison is done between single-stage and two-stage
voltage source inverter with chosen modulation strategies. Simulation studies of the proposed VSI
are carried out in MATLAB/SIMULINK.
Method Of Compensation Instability Of Frequency Modulators In The Absence Of ...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Similar to Solar Panel Using Active Stacked Npc Multi Level Converter (20)
This document describes an automatic safety door lock system for cars that uses infrared sensors and a hydraulic piston to prevent injuries caused by closing car doors. The system uses IR sensors placed along the door and outer panel connected to a microcontroller. When an object is detected between the closing door and outer panel, the sensors transmit a signal to the microcontroller which activates a relay driver to extend the hydraulic piston to stop the door from closing. The system aims to prevent the over 120,000 injuries that occur annually from unexpected car door closings.
Extrusion can be defined as the process of subjecting a material to compression so that it is forced to
flow through an opening of a die and takes the shape of the hole. Multi-hole extrusion is the process of
extruding the products through a die having more than one hole. Multi-hole extrusion increases the production
rate and reduces the cost of production. In this study the ram force has calculated experimentally for single hole
and multi-hole extrusion. The comparison of ram forces between the single hole and multi-hole extrusion
provides the inverse relation between the numbers of holes in a die and ram force. The experimental lengths of
the extruded products through the various holes of multi-hole die are different. It indicates that the flow pattern
is dependent on the material behavior. The micro-hardness test has done for the extruded products of lead
through multi-hole die. It is observed that the hardness of the extruded lead products from the central hole is
found to be more than that of the products extruded from other holes. The study suggests that multi-hole
extrusion can be used for obtaining the extruded products of lead with varying hardness. The micro-structure
study has done for the lead material before and after extrusion. It is observed that the size of grains of lead
material after extrusion is smaller than the original lead.
Analysis of Agile and Multi-Agent Based Process Scheduling Modelirjes
As an answer of long growing frustration of waterfall Software development life cycle concepts,
agile software development concept was evolved in 90’s. The most popular agile methodologies is the Extreme
Programming (XP). Most software companies nowadays aim to produce efficient, flexible and valuable
Software in short time period with minimal costs, and within unstable, changing environments. This complex
problem can be modeled as a multi-agent based system, where agents negotiate resources. Agents can be used to
represent projects and resources. Crucial for the multi-agent based system in project scheduling model, is the
availability of an effective algorithm for prioritizing and scheduling of task. To evaluate the models, simulations
were carried out with real life and several generated data sets. The developed model (Multi-agent based System)
provides an optimized and flexible agile process scheduling and reduces overheads in the software process as it
responds quickly to changing requirements without excessive work in project scheduling.
Effects of Cutting Tool Parameters on Surface Roughnessirjes
This paper presents of the influence on surface roughness of Co28Cr6Mo medical alloy machined
on a CNC lathe based on cutting parameters (rotational speed, feed rate, depth of cut and nose radius).The
influences of cutting parameters have been presented in graphical form for understanding. To achieve the
minimum surface roughness, the optimum values obtained for rpm, feed rate, depth of cut and nose radius were
respectively, 318 rpm, 0,1 mm/rev, 0,7 mm and 0,8 mm. Maximum surface roughness has been revealed the
values obtained for rpm, feed rate, depth of cut and nose radius were respectively, 318 rpm, 0,25 mm/rev, 0,9
mm and 0,4 mm.
Possible limits of accuracy in measurement of fundamental physical constantsirjes
The measurement uncertainties of Fundamental Physical Constants should take into account all
possible and most influencing factors. One from them is the finiteness of the model that causes the existence of
a-priori error. The proposed formula for calculation of this error provides a comparison of its value with the
actual experimental measurement error that cannot be done an arbitrarily small. According to the suggested
approach, the error of the researched Fundamental Physical Constant, measured in conventional field studies,
will always be higher than the error caused by the finite number of dimensional recorded variables of physicalmathematical
models. Examples of practical application of the considered concept for measurement of fine
structure constant, speed of light and Newtonian constant of gravitation are discussed.
Performance Comparison of Energy Detection Based Spectrum Sensing for Cogniti...irjes
With the rapid deployment of new wireless devices and applications, the last decade has witnessed a growing
demand for wireless radio spectrum. However, the policy of fixed spectrum assignment produces a bottleneck for more
efficient spectrum utilization, such that a great portion of the licensed spectrum is severely under-utilized. So the concept of
cognitive radio was introduced to address this issue.The inefficient usage of the limited spectrum necessitates the
development of dynamic spectrum access techniques, where users who have no spectrum licenses, also known as secondary
users, are allowed to use the temporarily unused licensed spectrum. For this purpose we have to know the presence or
absence of primary users for spectrum usage. So spectrums sensing is one of the major requirements of cognitive radio.Many
spectrum sensing techniques have been developed to sense the presence or absence of a licensed user. This paper evaluates
the performance of the energy detection based spectrum sensing technique in noisy and fading environments.The
performance of the energy detection technique will be evaluated by use of Receiver Operating Characteristics (ROC) curves
over additive white Gaussian noise (AWGN) and fading channels.
Comparative Study of Pre-Engineered and Conventional Steel Frames for Differe...irjes
In this paper, the conventional steel frames having triangular Pratt truss as a roofing system of 60 m
length, span 30m and varying bay spacing 4m, 5m and 6m respectively having eaves level for all the portals is at
10m and the EOT crane is supported at the height of 8m from ground level and pre-engineered steel frames of
same dimensions are analyzed and designed for wind zones (wind zone 2, wind zone 3, wind zone 4 and wind
zone 5) by using STAAD Pro V8i. The study deals with the comparative study of both conventional and preengineered
with respect to the amount of structural steel required, reduction in dead load of the structure.
Flip bifurcation and chaos control in discrete-time Prey-predator model irjes
The dynamics of discrete-time prey-predator model are investigated. The result indicates that the
model undergo a flip bifurcation which found by using center manifold theorem and bifurcation theory.
Numerical simulation not only illustrate our results, but also exhibit the complex dynamic behavior, such as the
periodic doubling in period-2, -4 -8, quasi- periodic orbits and chaotic set. Finally, the feedback control method
is used to stabilize chaotic orbits at an unstable interior point.
Energy Awareness and the Role of “Critical Mass” In Smart Citiesirjes
This document proposes a novel analytical model to define a new concept of critical mass in the context of spreading energy awareness in smart cities. The model incorporates centrality measures in both single-layer and multilayer social networks. Simulation results show that including centrality measures and a multilayer approach lowers the critical mass needed to trigger and spread good consumer habits. Specifically, the model calculates critical mass values using eigenvector centrality in single layers and a heterogeneous eigenvector-like centrality in multilayers. Considering network structure and central nodes' influence allows a smaller critical mass to foster diffusion compared to models that do not account for centrality. Extending the analysis to multilayers further reduces critical mass by increasing tie strength between nodes.
A Firefly Algorithm for Optimizing Spur Gear Parameters Under Non-Lubricated ...irjes
Firefly algorithm is one of the emerging evolutionary approaches for complex and non-linear
optimization problems. It is inspired by natural firefly‟s behavior such as movement of fireflies based on
brightness and by overcoming the constraints such as light absorption, obstacles, distance, etc. In this research,
firefly‟s movement had been simulated computationally to identify the best parameters for spur gear pair by
considering the design and manufacturing constraints. The proposed algorithm was tested with the traditional
design parameters and found the results are at par in less computational time by satisfying the constraints.
The Effect of Orientation of Vortex Generators on Aerodynamic Drag Reduction ...irjes
One of the main reasons for the aerodynamic drag in automotive vehicles is the flow separation
near the vehicle’s rear end. To delay this flow separation, vortex generators are used in recent vehicles. The
vortex generators are commonly used in aircrafts to prevent flow separation. Even though vortex generators
themselves create drag, but they also reduce drag by delaying flow separation at downstream. The overall effect
of vortex generators is more beneficial and proved by experimentation. The effect depends on the shape,size and
orientation of vortex generators. Hence optimized shape with proper orientation is essential for getting better
results.This paper presents the effect of vortex generators at different orientation to the flow field and the
mechanism by which these effects takes place.
An Assessment of The Relationship Between The Availability of Financial Resou...irjes
The availability of financial resources is an important element in impacting the success of a planning
process for an effective physical planning. The extent to which however, they are articulated in the process
remained elusive both in scholarly and public discourse. The objective of this study wastherefore, to examine
the extent to which financial resources affect physical planning. In doing so, the study examinedwhether
financial resources were adequate or not to facilitate planning processes in Paidha. According to the study
findings,budget prioritization and ceilings are still a challenge in Paidha Town Council. This is partly due
limited level of knowledge of physical planning among the officials of Paidha Town Council. As a result, there
were no dedicated budget line for routine inspection of physical development plan compliance and enforcement
tools in Paidha. In conclusion, in addressing uncoordinated patterns of physical development that characterize
Uganda‟s urban centres, a critical starting point ought to be the analysis of physical planning process. The
research of this kind is not only significant to other emerging urban centres facing poor a road network,
mushrooming informal settlements and poor social services including poor pattern of residential and commercial
developments but also to all institutions that are involved in planning these towns. Knowing the extent of need
for financial influences in planning may assist local authorities to take the processes of planning seriously which
will help enhance the sustainable development of emerging urban centres including Paidha.
The Choice of Antenatal Care and Delivery Place in Surabaya (Based on Prefere...irjes
This study analyzed factors affecting the utilization of antenatal care and delivery places in Surabaya, Indonesia based on preferences and choice theory. The study found that:
1) Nearly half of women chose healthcare for delivery based on information from others
2) Most women's main criteria for choosing a delivery place was that it was safe, comfortable and cheap
3) The majority of women's primary choice for a delivery place was one that was close, comfortable and cheap
Prediction of the daily global solar irradiance received on a horizontal surf...irjes
This document presents a new approach for predicting the daily global solar irradiance received on a horizontal surface as a function of local daytime and the maximum daily value. An exponential distribution function is suggested and compared to experimental data from several locations. The maximum daily value (qmax) is estimated theoretically in terms of the solar constant adjusted for earth-sun distance variation. Computed values using the new approach show good agreement with experimental data, within 16% error except for some extreme points.
HARMONIC ANALYSIS ASSOCIATED WITH A GENERALIZED BESSEL-STRUVE OPERATOR ON THE...irjes
This document summarizes a research paper that considers a generalized Bessel-Struve operator on the real line. It defines generalized Bessel-Struve and Weyl integral transforms, which are shown to be transmutation operators relating the generalized Bessel-Struve operator to derivatives. These tools are then used to develop a new harmonic analysis associated with the generalized Bessel-Struve operator, including generalized Sonine integral transforms. Key results proven include Paley-Wiener theorems and properties of the various integral transforms.
The Role of Community Participation in Planning Processes of Emerging Urban C...irjes
This document summarizes a research study examining the level of community participation in the physical planning process in Paidha Town, Uganda. The study found that community participation in planning is very low, limited mostly to a few mass meetings. Few community members are actually involved in planning. Even those involved do not understand their rights and roles. Physical planning has not been adequately prioritized or funded. To improve participation, the study recommends involving communities at different administrative levels from villages to the town council, and using a wider range of participatory methods beyond just meetings. Overall, the study finds that community participation in planning is still limited and needs to be strengthened for more sustainable urban development.
Understanding the Concept of Strategic Intentirjes
This document summarizes the concept of strategic intent in strategic management. It begins by discussing the origins and evolution of strategic management from Greek history to modern theories. It then defines strategic intent, comparing various authors' definitions. A key model by Hamel and Prahalad links strategic intent to other strategic components like foresight and core competencies. Strategic intent inspires long-term thinking beyond strategic planning alone. It provides direction and commitment to help organizations shape competitive priorities and capabilities for the future. Chief executives play a critical role in developing strategic intent to guide organizational progress over 10-20 years.
The (R, Q) Control of A Mixture Inventory Model with Backorders and Lost Sale...irjes
This document summarizes an inventory model that considers a mixture of backorders and lost sales when stockouts occur. The model has the following key features:
1) The set-up cost and lead time are controllable variables that can be optimized.
2) Instead of minimizing stockout costs, the model employs a service level constraint to bound the stockout level per cycle.
3) The model is solved using a genetic algorithm approach to find optimal values for ordering quantity, set-up cost, and lead time that minimize total costs while satisfying the service level constraint.
Relation Between Stress And Menstrual Cycle At 18-21 Years Of Ageirjes
The document summarizes a study that examined the relationship between stress and menstrual cycles in Indonesian nursing students ages 18-21. It found:
1) Nearly half (45.5%) of the 132 students studied experienced irregular menstrual cycles.
2) Slightly over half (50.8%) of students reported experiencing stress.
3) There was a significant relationship between stress and irregular menstrual cycles, with stressed students over 4 times more likely to have irregular cycles.
The study concluded that most of the nursing students experienced irregular menstrual cycles and stress, and that stress was strongly correlated with irregular menstrual periods.
Wave Transmission on Submerged Breakwater with Interlocking D-Block Armorirjes
1. The document summarizes a study on wave transmission through a submerged breakwater with interlocking D-block armor. Laboratory experiments were conducted to determine how water depth, wave period, structure height, and wave steepness influence the transmission coefficient.
2. Regression analysis showed that transmission coefficient (Kt) is most influenced by the ratio of wave length to top width, ratio of structure height to water depth, and ratio of wave height to wave period squared. A formula for Kt in terms of these parameters was developed.
3. Comparisons with previous studies show the same trend that higher wave steepness results in lower transmission coefficient, validating the results. The study provides useful insights into breakwater design using inter
TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
How does your privacy program stack up against your peers? What challenges are privacy teams tackling and prioritizing in 2024?
In the fifth annual Global Privacy Benchmarks Survey, we asked over 1,800 global privacy professionals and business executives to share their perspectives on the current state of privacy inside and outside of their organizations. This year’s report focused on emerging areas of importance for privacy and compliance professionals, including considerations and implications of Artificial Intelligence (AI) technologies, building brand trust, and different approaches for achieving higher privacy competence scores.
See how organizational priorities and strategic approaches to data security and privacy are evolving around the globe.
This webinar will review:
- The top 10 privacy insights from the fifth annual Global Privacy Benchmarks Survey
- The top challenges for privacy leaders, practitioners, and organizations in 2024
- Key themes to consider in developing and maintaining your privacy program
Infrastructure Challenges in Scaling RAG with Custom AI modelsZilliz
Building Retrieval-Augmented Generation (RAG) systems with open-source and custom AI models is a complex task. This talk explores the challenges in productionizing RAG systems, including retrieval performance, response synthesis, and evaluation. We’ll discuss how to leverage open-source models like text embeddings, language models, and custom fine-tuned models to enhance RAG performance. Additionally, we’ll cover how BentoML can help orchestrate and scale these AI components efficiently, ensuring seamless deployment and management of RAG systems in the cloud.
AI 101: An Introduction to the Basics and Impact of Artificial IntelligenceIndexBug
Imagine a world where machines not only perform tasks but also learn, adapt, and make decisions. This is the promise of Artificial Intelligence (AI), a technology that's not just enhancing our lives but revolutionizing entire industries.
GraphRAG for Life Science to increase LLM accuracyTomaz Bratanic
GraphRAG for life science domain, where you retriever information from biomedical knowledge graphs using LLMs to increase the accuracy and performance of generated answers
Unlocking Productivity: Leveraging the Potential of Copilot in Microsoft 365, a presentation by Christoforos Vlachos, Senior Solutions Manager – Modern Workplace, Uni Systems
“An Outlook of the Ongoing and Future Relationship between Blockchain Technologies and Process-aware Information Systems.” Invited talk at the joint workshop on Blockchain for Information Systems (BC4IS) and Blockchain for Trusted Data Sharing (B4TDS), co-located with with the 36th International Conference on Advanced Information Systems Engineering (CAiSE), 3 June 2024, Limassol, Cyprus.
Goodbye Windows 11: Make Way for Nitrux Linux 3.5.0!SOFTTECHHUB
As the digital landscape continually evolves, operating systems play a critical role in shaping user experiences and productivity. The launch of Nitrux Linux 3.5.0 marks a significant milestone, offering a robust alternative to traditional systems such as Windows 11. This article delves into the essence of Nitrux Linux 3.5.0, exploring its unique features, advantages, and how it stands as a compelling choice for both casual users and tech enthusiasts.
Observability Concepts EVERY Developer Should Know -- DeveloperWeek Europe.pdfPaige Cruz
Monitoring and observability aren’t traditionally found in software curriculums and many of us cobble this knowledge together from whatever vendor or ecosystem we were first introduced to and whatever is a part of your current company’s observability stack.
While the dev and ops silo continues to crumble….many organizations still relegate monitoring & observability as the purview of ops, infra and SRE teams. This is a mistake - achieving a highly observable system requires collaboration up and down the stack.
I, a former op, would like to extend an invitation to all application developers to join the observability party will share these foundational concepts to build on:
Building Production Ready Search Pipelines with Spark and MilvusZilliz
Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
Dr. Sean Tan, Head of Data Science, Changi Airport Group
Discover how Changi Airport Group (CAG) leverages graph technologies and generative AI to revolutionize their search capabilities. This session delves into the unique search needs of CAG’s diverse passengers and customers, showcasing how graph data structures enhance the accuracy and relevance of AI-generated search results, mitigating the risk of “hallucinations” and improving the overall customer journey.
Threats to mobile devices are more prevalent and increasing in scope and complexity. Users of mobile devices desire to take full advantage of the features
available on those devices, but many of the features provide convenience and capability but sacrifice security. This best practices guide outlines steps the users can take to better protect personal devices and information.
Pushing the limits of ePRTC: 100ns holdover for 100 daysAdtran
At WSTS 2024, Alon Stern explored the topic of parametric holdover and explained how recent research findings can be implemented in real-world PNT networks to achieve 100 nanoseconds of accuracy for up to 100 days.
UiPath Test Automation using UiPath Test Suite series, part 6DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
Leonard Jayamohan, Partner & Generative AI Lead, Deloitte
This keynote will reveal how Deloitte leverages Neo4j’s graph power for groundbreaking digital twin solutions, achieving a staggering 100x performance boost. Discover the essential role knowledge graphs play in successful generative AI implementations. Plus, get an exclusive look at an innovative Neo4j + Generative AI solution Deloitte is developing in-house.
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdfMalak Abu Hammad
Discover how MongoDB Atlas and vector search technology can revolutionize your application's search capabilities. This comprehensive presentation covers:
* What is Vector Search?
* Importance and benefits of vector search
* Practical use cases across various industries
* Step-by-step implementation guide
* Live demos with code snippets
* Enhancing LLM capabilities with vector search
* Best practices and optimization strategies
Perfect for developers, AI enthusiasts, and tech leaders. Learn how to leverage MongoDB Atlas to deliver highly relevant, context-aware search results, transforming your data retrieval process. Stay ahead in tech innovation and maximize the potential of your applications.
#MongoDB #VectorSearch #AI #SemanticSearch #TechInnovation #DataScience #LLM #MachineLearning #SearchTechnology
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdf
Solar Panel Using Active Stacked Npc Multi Level Converter
1. International Refereed Journal of Engineering and Science (IRJES)
ISSN (Online) 2319-183X, (Print) 2319-1821
Volume 4, Issue 2 (February 2015), PP.20-33
www.irjes.com 20 | Page
Solar Panel Using Active Stacked Npc Multi Level Converter
1
M.Saravanan, 2
Mr. S.Annadurai
1
Bharath University
2
M.E Assistant Professor
Abstract:- In this project, the operation and the features of a new three-level converter are presented with PV
source and boost converter. The proposed topology was named three-level active-stacked neutral point clamped.
It is a derivative of the 3L-SNPC structure, having two additional active switches connected anti parallel with
the clamp diodes. The main advantage of 3L-ASNPC converter is the reduction of the average switching
frequency for all power devices. In the same time, the apparent switching frequency of the output voltage is
doubled.
Keywords:- Multilevel converter solar panel rectifier matlab/Simulink
Fig.1.1
I. INTRODUCTION
Multilevel structures have been studied for over 25 years, and they represent an intelligent solution to
connect serial switches [1]–[9]. The first developed topology consisted of a serial connection of single-phase
inverters with dc separate sources [10]–[14]. This structure was followed by a stacked commutation cell concept
in order to obtain a multilevel conversion [stacked cells (sc)] [15]–[17].following the sc structure, a new
multilevel neutral-point-clamped (npc) topology was developed [18]. The three-level npc (3l-npc) converter is a
very popular multilevel structure, being a particular way of implementing the 3l-sc topology. the role of the
middle switches in the sc structure is taken by the inner switches and by the two clamp diodes [19].later, another
invention introduced the concept of multilevel converter with flying capacitors (fcs) [20]–[24]. The additional
expense of fcs, particularly at low and moderate switching frequencies (200 hz–1 khz), is the main disadvantage
of the fc topology.
II. PROPOSED 3 L-ASNPC CONVERTER
Static converter design has to ensure that, in all specific operation conditions, the junction temperature
of power devices does not exceed the admitted limits. The junction temperature of each power device is a direct
consequence of conduction and switching losses. A better temperature distribution enable substantial increase of
the converter’s output power at nom- operation or alternatively an increase of the switching frequency [25],
[26].The unequal loss distribution among the semiconductors represents one major disadvantage for the 3L-SC
and 3L-NPC converters. A better balancing of total losses in power devices has been obtained by developing
3L-active NPC (3L-ANPC) and 3L-stacked NPC (3L-SNPC) topologies [27]–[29].In [28], a feedback-
controlled loss balancing system has been proposed for the 3L-ANPC structure. Based on an online estimation
of junction temperatures, appropriate commutations are selected in real time such that the hottest devices are not
stressed with significant switching losses. This special modulation leads to the balance of junction temperatures
of power devices and modifies the output voltage spectrum. However, the control requires a notable amount of
2. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 21 | Page
additional computational power, mainly for junction temperature estimation. Drawbacks are the higher cost and
the increased control complexity.
Fig: 1.2
The 3L-ANPC and 3L-SNPC have more zero switching states that can be used to double the apparent
switching frequency [30], [31]. Due to the structural particularities, some power devices switch only on a half
cycle, while others switch on the entire cycle. These last ones have the biggest switching losses, being the most
stressed power devices that limit the maximum switching frequency or the maximum power output. In this
paper, a new three-level converter is presented (Fig. 1).The proposed topology is named 3L-active-stacked NPC
(3L-ASNPC). It is a derivative of the 3L-SNPC structure, having two additional active switches connected anti
parallel with the clamp diodes.
The main advantage of the 3L-ASNPC converter is the half reduction of the average switching
frequency on the entire cycle for all the power devices. In the same time, the apparent switching frequency of
the output voltage is twice the switching frequency. Experimental and simulation results are shown in order to
validate the proposed topology and the analysis of the switching states.
Existing system limitation:
• The 3L-ANPC and 3L-SNPC have more zero switching states that can be used to double the apparent
switching frequency.
• Due to the structural particularities, some power devices switch only on a half cycle, while others switch
on the entire cycle.
• These last ones have the biggest switching losses, being the most stressed power devices that limit the
maximum switching frequency or the maximum power output.
Proposed system merits:
• A new three-level converter is presented.
• The proposed topology is named 3l-active-stacked NPC (3l-asnpc).
• It is a derivative of the 3l-SNPC structure, having two additional active switches connected anti parallel
with the clamp diodes.
• Solar panel will be added.
3. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 22 | Page
III. CIRCUIT DIAGRAM EXPLANATIONS
The classical 3L-NPC converter (Fig. 2) is a very popular multilevel structure used in high-power
medium-voltage applications. In this circuit, the dc supply voltage is split into three levels by two series-
connected capacitors.
By using a sinusoidal pulse width modulation (PWM) strategy, it is observed that the 3L-NPC topology
has only three commutation states: P, O, and N (Table I). Switches S1, S 1c,S2, and S 2 care complementary
controlled on the entire cycle.
A cycle represents a period of the reference voltage. The states P and N correspond to a direct
connection of the load at the dc supply voltage. The state P(Vdc/2) is obtained by turning on switches S 1 and S
2, while the state N (−V dc /2) is obtained by turning on S1c and S 2c . The inner switches S 1c and S 2 are
turned on in order to obtain the state O. In this case, the inductive load current passes through two different
paths, depending on its direction. The positive load current passes through Du and S 2 , while the negative load
current passes through Dd and S 1c .
Three-level ANPC converter.
Fig: 3.1.1Circuit Diagram
Fig: 3.1.2
The control of power devices depends on the sign of the reference voltage. When the sinusoidal
reference voltage is positive, the control of power devices S1 and S 1c is made at switching frequency (f sw ),
while S 2 is turned on, and S 2c is turned off. When the sinusoidal reference voltage is negative, the control of
power devices S2 and S 2c is made at f sw , while S1 is turned off, and S 1c is turned on. As a result, the
average switching frequency on a cycle (fav) is equal to half of fsw(fav = fsw/2) , while the apparent switching
frequency of theoutput voltage (fap) is equal to fsw(fap = fsw).The 3L-ANPC converter is a derivative of the
3L-NPC topology, having two active switches connected antiparallel with the clamp diodes (Fig. 3). This
structure can be controlled using different PWM strategies [30].
The PWM strategy analysed in this paper leads to the doubling of the apparent switching frequency
(fap=2f sw ). The sinusoidal reference voltage Sr is compared with two carrier waves (S d1 and S d2 ), phase
shifted with half of the switching period (T sw /2) . Following the comparison process,six switching states are
obtained: P, O + 1 , O + 2 ,N, O – 1 , and O – 2 (Fig. 4). Switches S 2 and S 2c are complementary controlled on
the entire cycle. The control of the other power devices depends on the sign of the reference voltage. When the
reference voltage is positive, S 1 and S 1c are complementary controlled [Fig. 4(a)]. S 3 receives the same
control as S 1 , while S 3c is turned off. In this case (Sr> 0) , three switching states P, O + 1 , and O + 2 are
obtained. Switches S 1 and S 2 are turned on in order to obtain the switching state P. S3 is also turned on, but it
4. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 23 | Page
does not influence the paths of the load current [Fig. 5(a)]. The state O + 1 is obtained when S 1c and S 2 are
turned on [Fig. 5(b)].
Fig.3.1.3. Current paths for 3L-ANPC converter.(a) State P. (b) States O+1andO−2.
(c) States O+2and O−1. (d) State N.
The state O +2 is obtained when S 2c and S 3 are turned on. S1 is also turned on, but it does not
influence the paths of the load current [Fig. 5(c)]. When the reference voltage is negative, the other three
switching states (N, O – 1 , and O – 2 ) are obtained [ ig. 4(b)]. Switches S3 and S 3c are complementary
controlled.
S 1c receives the same control like S3c , while S 1 is turned off. State N is obtained by turning on
switchesS2c and S 3c . S 1c is also turned on, but it does not influence the paths of the load current [Fig. 5(d)].
The state O – 1 is obtained when S 2c and S 3 are turned on [Fig. 5(c)], while the state O 2 is obtained when S
1c and S 2 are turned on. S 3c is also turned on, but it does not influence the paths of the load current for O – 2
[Fig. 5(b)].
During the states P and N, two active switches or two diodes are in conduction. In the case of states O
+ 1 , O + 2 , O – 1 , and O – 2 , one active switch and one diode are in conduction. For the states O + 1 , O − 2 ,
O + 2 , and O – 1 , the paths of the load current are the same. The switches can be grouped in three pairs: S 1
−S 1c , S 2 −S 2c,, and S 3 −S 3c, . These can be complementary controlled and turned off simultaneously
(including the dead times intervals), but they cannot be turned on in the same time.
The controls of the outer switches S 1 and S 3c are realized at switching frequency (f sw ) only on a
half cycle (Fig. 4). As a result, their average switching frequency on a cycle is equal to half of the switching
frequency (f av = f sw/2).
Fig. 3.1.4 shows the simulated waveforms for switch S3 .The frequency of the sinusoidal reference voltage
(fR ) was set to 50 Hz, and the modulation index (M ) was 0.9.
5. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 24 | Page
In Fig. 3.1.5. It is observed that S2 operates at f sw on the entire cycle (fav = f sw ). S 2c is complementary
controlled with S 2 , and it also operates at f sw on the entire cycle (f av = f sw ).
It is observed that S 3 commutes at f sw only on a half cycle, whenSr< 0. On the other half cycle,S3
commutes at zero voltage. Thus, the average switching frequency for S3 is considered half of f sw . Due to the
symmetry, the average switching frequency for S1c is also considered half of f sw (f av = f sw /2) . Voltage and
current simulated waveforms for switch S2 are shown
The 3L-SNPC converter (Fig. 8) is a derivative of the 3L-SC and 3L-NPC topologies [29] and can be
controlled using the same PWM strategy shown in Fig. 4. It presents the same advantage of doubling the
apparent switching frequency (f ap =2f sw ) like the 3L-ANPC topology.
Switches S 2 and S 2c are controlled on the entire cycle with fsw (fav = fsw ), while the other ones
(including the clamp diodes Du and Dd) commute at fsw only on a half cycle (fav = f Sw /2) . The existence of a
single zero switching state represents a limitation of the 3L-NPC structure that has direct consequences on the
total loss distribution among the switches [27], [30]. The operation of S2 and S2c at f sw on the entire cycle is
also a structural limitation of the 3L-ANPC and 3L-SNPC converters. In order to balance the average switching
frequency for all the power devices, a new multilevel converter is proposed.
3. NEW 3L-ASNPC CONVERTER
The 3L-ASNPC converter (Fig. 1) is a derivative from the 3L-SNPC structure, having two additional
active switches connected ant parallel with the clamp diodes. All the switches support a voltage equal to V Dc
/2. The proposed topology has more degrees of freedom in comparison with the 3L-ANPC and 3L-SNPC
converters. The proposed PWM strategy (Fig. 9) allows an average switching frequency that is equal to half of
the switching frequency (f av = f Sw /2) for all the power devices. In the same time, the apparent switching
frequency of the output voltage is twice the switching frequency(fap=2fsw). In order to emphasize the
advantages, the switching states and sequences are analyzed at one switching period T sw for each polarity of
the reference voltage.
6. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 25 | Page
Fig.3.2.2. Proposed PWM strategy for 3L-ASNPC converter. (a) Sr> 0.(b) Sr< 0.
The reference voltage S r is compared with two carrier waves (S d1 and S d2 ) that are phase shifted
with T sw /2. Following the comparison process, six switching states are also obtained: P,O+1, O+2,N, O−1 ,
and O−2(Table II) When the reference voltage is positive, S1 , S 1c , S 2 , and S 2c are complementary
controlled [Fig. 9(a)]. The other power devices ( S 3 , S 3c , S 4 , and S 4c ) have a particular control. S 3
receives the same control like S 1 , while S 3c , S 4 , and S 4c are turned off. The control of S3 does not
influence the paths of the load current in the state P, but it contributes in obtaining the state O + 2 . When the
reference voltage is negative, S3 , S 3c , S 4 , and S4c , are complementary controlled [Fig. 9(b)]. The other
power devices ( S 1 , S 1c , S 2 , and S 2c ) have also a particular control.S2c receives the same control likeS 4c
, while S 1, S 1c,and S2are turned off. The control of S 2c does not influence the paths of the load current in the
state N, but it contributes in obtaining the state O – 2.
Fig:3.2.3.Current paths corresponding to the states O+1, O+2, O−1, and O−2.
7. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 26 | Page
Fig: 3.2.4
A. Switching States State P is obtained by turning on switches 1 and S 2 . S 3 is also turned on, but it
does not influence the paths of the load current. In order to obtain the switching state N, switches S3c and S 4c
are turned on. S 2c is also turned on, but it does not influence the paths of the load current. The distribution of
the conduction losses during states P and N cannot be influenced. For the zero-voltage level, four different
control sequences are used. The distribution of the conduction losses during the zero states can be controlled by
selecting the upper (S1c −S 2 ), lower (S4 −S 3c ), or middle (S2c −S 3 ) current paths. During the zero states,
one active switch and one diode are in conduction. Even if more than two devices turn on, only one active
switch and one diode will be in conduction, depending on the load current direction.
The zero states O + 1 and O + 2 are obtained when the reference voltage is positive, while the states O
1 and O – 2 are obtained when the reference voltage is negative. The zero stateO + 1 is obtained when switches
S 1c and S 2 are turned on, while the others are turned off [Fig. 10(a)]. The state O + 2 isobtained when S 2c and
S 3 are turned on. S 1 is also turned on, but it does not influence the paths of the load current [Fig. 10(b)]. The
other switches (S1c , S 2 , S 3c S 4 , and S 4c ) are turned off.
The state O −1is obtained when switches S3cand S 4 are turned on, while the other ones are turned off
[Fig. 10(c)]. zero switching state O – 2 is obtained when S 2c and S 3 are turned on. S 4c is also turned on, but it
does not influence the paths of the load current [Fig. 10(d)]. The other switches ( S1 , S 1c , S 2 , S3c , and S 4 )
are turned off, and the paths of the load current are similar to the state O + 2 . The switches from the middle
side ( S2 cand S 3)havea particular control in reducing their average switching frequency on the entire cycle (f
av = f sw /2) . When the reference voltage is negative, S2c receives the same control like S 4c , and it commutes
at zero voltage (Fig. 11). When the reference voltage is positive, S3 receives the same control like S1 , and it
also commutes at zero voltage.
B. Commutations
The commutation to or from the zero states O−1, O− 2, O+1, and O+ 2determine the distribution of the
switching losses. Having the same operation conditions and the same features of power devices, the proposed
PWM strategy has the same efficiency as the other analysed 3L structures. The four zero switching states are
investigated sub sequent.
For the commutation P →O+1, the phase current is com-mutated to the upper current path (S1c −S 2). First,
S1has to be turned off, and then, (after a dead time) S1cis turned on. For the commutation O+1→P, switch S1cis
turned off first, and then,(after a dead time) S1is turned on.
Fig: 3.2.5
8. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 27 | Page
The paths of the load current during the dead time (S1and S 1care turned off) are shown in Fig. 12(a).The
commutation P →O+2differs from the commutation P →O+1. In this case, the phase current is commutated to
the middle current path (S2c −S 3). S2has to be turned off, and then,(after a dead time) S2cis turned on. For the
commutation O+2→P, S2chas to be turned off, and then, S2isturned on.
Fig: 3.2.6
The load current paths during the dead time ( S2 and S2 care turned off) .The voltage and current
waveforms of S2on a cycle are shown in Fig. 13. It is observed that S2commutes at fs won a half cycle when
Sr> 0. On the second half cycle (Sr< 0), the load current does not pass through S2. Due to the symmetry of this
topology, switch S2c has a similar operation. Through the commutation N →O − 1 , the load current is
commutated to the lower current path (S4 −S 3c ).First, S4c is turned off, and S 4is turned on after a dead time.
For the commutation O 1 →N, switch S 4 is turned off first, and then, (after a dead time) S 4c is turned on. The
paths of the load current during the dead time ( S4 and S 4c are turned off) . During the commutation N →O −2,
the load current is commutated to the middle current path(S2c −S 3 ). S 3c has to be turned off, and then, (after a
dead time) S3 is turned on. In the case of commutation O − 2 →N, S 3 is turned off, and S 3c is turned on after a
dead time. Fig. 12(d) shows the load current paths during the dead time (S 3 and S 3c are turned off). In
conclusion, each power device of the proposed structure operates at f sw only on a half cycle, and the average
switching frequency on the entire cycle is equal to half of the switching frequency (f av = f sw /2) . In the same
time, the apparent switching frequency of the output voltage is twice the switching frequency (fap =2f Sw ).
This advantage leads to a better balancing of the total losses in power devices.
3.3 Solar energy
Solar Energy is about the future as well as the present. With unlimited potential, Solar Energy is a
clean, efficient, and sustainable form of renewable energy. Solar Energy in the near future is also a sound
financial decision. With Solar panels powering your home, you'll see this every month when your electricity bill
arrives. Finally, Solar Energy is a green decision - you'll feel good knowing that you will leave the world a
greener, better place for your children.
Today, the worldwide demand for solar photovoltaic (PV) energy is greater than supply. It is one of the
fastest growing forms of renewable energy. As manufacturing becomes more efficient, the cost of PV systems
continues to drop. Prices have reduced 25 fold over the last 20 years.
Commercially, even electrical utilities are looking to Solar for a more stable cost structure. Research
has shown that solar can even be effective in Northern climates. In California, electricity rates are increasing at a
rate of 6.7% per year. Solar provides a hedge against future rate hikes. And in many countries, you can sell your
surplus electricity back to the utility, generating a credit on your bill.
Not only is solar affordable, it is even more economical when you consider the alternative: the high
costs of fossil fuel pollution and global warming. In solar energy scored higher than all other forms of energy
when participants were asked what type of energy is best for future generations. Photovoltaic systems produce
electric power with no carbon dioxide (CO2) emissions. The Carbon emission offset is calculated at
approximately 7.5 tons of CO2 over the twenty-five year guaranteed life of one PV module
All in all, solar photovoltaic energy generation has a very bright future indeed.
9. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 28 | Page
Photovoltaic Anyone who has used a modern mathematical calculator can grasp the concept of photovoltaic
(PV). It is simply the process of converting energy from the Sun into electricity that can power everything from
household appliances and lights to commercial buildings and power plants.
In precisely the same way as the small solar cells on hand-held calculators eliminate the need for
batteries, PV can provide the world with a clean, reliable source of electricity and reduce our reliance on ever-
depleting fossil fuels.
The PV technology of the 21st century makes it possible. It employs layers of micro-fine crystalline
silicon to convert ordinary sunlight into small electrical charges. This process is then multiplied thousands of
times over to create, smaller than ever before, modules and systems that can generate enough electricity to
power entire towns.
It's important to note that PV is different from the solar thermal energy used for heating or in hot water
production. A single PV cell consists of two or more thin layers of semi-conducting material, most commonly
crystalline silicon. When the silicon is exposed to light, small electrical charges are generated and conducted
away by metal contacts as direct current (DC).
In order to maximize energy collection and conversion, single cells are connected together and housed
in a module. These modules are the building blocks of the PV systems and are, in turn, connected together to
generate usable volumes of electricity. In some instances, an inverter is also used to convert high voltage DC
into lower voltage AC power.
IV. NEUTRAL POINT CLAMPED MULTI-LEVEL CONVERTER
Multilevel topologies provide a clever way of connecting switches in series, thus enabling the
processing of voltages that are higher than the device rating. The industry need for medium voltage drives has
triggered considerable research in this field, in which most applications include drives for pumps, blowers,
compressors, conveyors, and the like. In general, multilevel converters are effective means of reducing
harmonic distortion and dv/dt of the output voltages, which makes this technology applicable to utility interface
and drives.
There are a limited number of topologies that provide multilevel voltages and are suitable for medium
voltage applications. The most known topologies are the neutral-point-clamped (NPC), the flying capacitor
(FC), and the cascaded H-bridge multilevel converters. Other topologies such as the hybrid converters have been
proposed as well, but they are not fully accepted for industrial applications. The NPC multilevel converter
shown in Figure 1(a) is a natural extension of the three-level converter presented by Nabae (NPC3L). As can be
seen, the multilevel NPC converter requires multiple clamping points to synthesize the different voltage levels
across the output. The disadvantage of multiple clamping points is a limitation on the maximum modulation
index that is allowed with active power to assure voltage sharing across all the dc link capacitors. Another
drawback of the multilevel NPC converter is the need for series connection of the clamping diodes . Figure 1(b)
illustrates a five-level floating capacitor converter. By properly using the dc link and floating capacitor voltages,
one can synthesize the required voltage levels across the output terminals. An interesting property of the floating
capacitor converter is that the redundant switching states can be used to achieve proper voltage control across
the floating capacitors. In general, the energy stored in the floating capacitors is a limiting factor to increasing
the number of voltage levels, which makes the five-level approach the most practical for industrial applications.
An increased number of voltage levels may only be practical from the view point of floating capacitor
requirements if the carrier frequency of the converter is increased. However, there are trade-offs that should be
observed between carrier frequency and switching losses in the converter. The cascaded H-bridge multilevel
converter shown in Figure 1(c) takes advantage of connecting single-phase inverters in series that are fed by
independent dc voltage sources. The approach can be extremely modular, and a stair-cased output voltage is
produced by adding and/or subtracting the voltages of the single-phase modules. The power flow may be bi-
directional if active front-end rectifiers are used in the single-phase modules. Although modular, the cascaded
H-bridge multilevel converter requires a complex transformer to provide the various independent dc sources.
Based upon the previous description, this paper proposes an active neutral-point-clamped (ANPC) multilevel
converter that combines the flexibility of the multilevel floating capacitor converter with the robustness of
industrial NPC converters to generate multilevel voltages. The proposed concept is described and supported by
simulation results, and experimental validation demonstrates the proposed technology.
3.5 Boost converter
The step-up dc-dc converter is known as boost converter. Its main applications are in regulated dc
power supplies and the regenerative braking of dc motors. The average output is always greater than the dc input
voltage. The output voltage is controlled by controlling the switch-duty cycle. When the switch is on, the diode
is reverse biased, and hence is the output stage. During the switch on mode the inductor gets the energy from the
supply and stores it. During switch o ―state, the diode becomes forward biased and the output stage receives the
10. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 29 | Page
energy from the inductor as well as the input. Thus the net energy transferred to the output from input is always
greater in a given switching cycle.
Fig: 3.4.1
A power stage can operate in continuous or discontinuous inductor current mode. In continuous
inductor current mode, current flows continuously in the inductor during the entire switching cycle in steady-
state operation. In discontinuous inductor current mode, inductor current is zero for a portion of the switching
cycle. It starts at zero, reaches peak value, and return to zero during each switching cycle. It is desirable for a
power stage to stay in only one mode over its expected operating conditions because the power stage frequency
response change s significantly between the two modes of operation.
3.5 Boost Steady-State Continuous Conduction Mode (CCM)
In continuous conduction mode, the boost power stage assumes two states per switching cycle. In the
on state, Q1 is on and D1 is off. In the off state, Q1 is off and D1 is on. A simple linear circuit can represent
each of the two states where the switches in the circuit are replaced by their equivalent circuit during each state.
Figure 2 shows the linear circuit diagram for each of the two states.
Fig: 3.5.1
3.7 Boost Power Stage States
The duration of the on state is D× T s =T ON, where D is the duty cycle set by the control circuit,
expressed as a ratio of the switch on time to the time of one complete switching cycle, T s . The duration of the
off state is T OFF.
11. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 30 | Page
Fig: 3.5.2
3.8 CCM Boost Power Stage Waveforms
Refer to Figures 1 and 2. The inductor-current increase can be calculated by using a version of the
familiar relationship:
The inductor current increase during the on state is given by:
The quantity ∆I L (+) is the inductor ripple current. During this period, all of the output load current is
supplied by output capacitor C. The inductor current decrease during the off state is given by: The quantity ∆I L
(-) is also the inductor ripple current.
In steady-state conditions, the current increase, ∆I L (+), during the on time and the current decrease,
∆I L (-), during the off time are equa l. Therefore, these two equations can be equated and solved for VO to
obtain the continuous conduction mode(CCM) boost voltage conversion relationship
3.9 Boost Steady-State Discontinuous Conduction Mode (DCM)
Figure 4 shows the inductor current condition where the power stage is at the boundary between
continuous and discontinuous mode. This is where the inductor current just falls to zero and the next switching
cycle begins immediately after the current reaches zero. From the charge and discharge of output capacitor, the
output current is given by:
Fig: 3.5.3
Boundary between Continuous and Discontinuous Mode
Further reduction in output load current puts the power stage into discontinuous current conduction mode
(DCM). The discontinuous mode power stage input-to-output relationship is quite different from the continuous
mode.
Fig: 3.5.4
Discontinuous Current Mode
The duration of the on state is T ON=D× T S, where D is the duty cycle set by the control circuit. The
duration of the off state is T OFF =D2 × T S . The idle time is the remainder of the switching cycle and is given
as T S -T ON-T OFF = D3× T S. These times are shown with the waveforms in Fig 3.5.5
12. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 31 | Page
Discontinuous Mode Boost Power Stage Waveforms
3.6 MOSFET
The MOSFET device belongs to the unipolar device family, because it uses only the majority carriers
in conduction.
MOSFET stands for metal oxide semiconductor field effect transistor. there are two types of MOSFET
depletion type MOSFET enhancement type MOSFET.
3.7 ADVANTAGES:
Half reduction of the average switching frequency on the entire cycle for all the power devices.
3.8 APPLICATION
High power application
traction applications
Industry applications
IV. SIMULATION
WAVE FORMS OUTPUT:
13. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 32 | Page
V. CONCLUSIONS
The 3L-ANPC and 3L-SNPC topologies allow the doubling of the apparent switching frequency. In the
frame of these structures, there are some power devices that switch only on a half cycle and others that switch
on the entire cycle. These last ones severely limit the output power or the maximum switching frequency. In
order to overcome this drawback, a new three-level converter has been presented in this project. The proposed
topology was named 3L-ASNPC. It is a derivative from the 3L-SNPC, having two additional active switches
connected antiparallel with the clamp diodes. The 3L-ASNPC structure has more degrees of freedom and can be
controlled using different PWM strategies. The proposed PWM strategy has six switching states and allows the
doubling of the apparent switching frequency. Another advantage of the proposed topology is the half reduction
of the average switching frequency on the entire cycle for all the power devices and voltage level is boosted
using boost converter. This characteristic makes the 3L-ASNPC topology an attractive solution, particularly for
medium-voltage and high-power applications.
REFERENCES
[1]. S. Bernet, ―Recent developments of high power converters for industry and traction applications,‖
IEEE Trans. Power Electron. , vol. 15, no. 6,pp. 1102–1117, Nov. 2000.
[2]. R. Teichmann, M. Malinowski, and S. Bernet, ―Evaluation of three-level rectifiers for low-voltage
utility applications,‖ IEEE Trans. Ind. Electron.,vol. 52, no. 2, pp. 471–481, Apr. 2005.
[3]. J. Rodríguez, J.-S. Lai, and F. Z. Peng, ―Multilevel inverters: A survey of topologies, controls, and
applications,‖ IEEE Trans. Ind. Electron.,vol. 49, no. 4, pp. 724–738, Aug. 2002.
[4]. J. Rodríguez, S. Bernet, B. Wu, J. O. Pontt, and S. Kouro, ―Multi-level voltage-source-converter
topologies for industrial medium-voltage drives,‖ IEEE Trans. Ind. Electron. , vol. 54, no. 6, pp. 2930–
2945,Dec. 2007.
[5]. M. Carpita, M. Marchesoni, M. Pellerin, and D. Moser, ―Multilevel con-verter for traction applications:
Small-scale prototype tests results,‖ IEEE Trans. Ind. Electron., vol. 55, no. 5, pp. 2203–2212, May
2008.
[6]. J. Rodríguez, L. Morán, P. Correa, and C. Silva, ―A vector control tech-nique for medium-voltage
inverters,‖ IEEE Trans. Ind. Electron. , vol. 49, no. 4, pp. 882–888, Aug. 2002.
[7]. B. P. McGrath and D. G. Holmes, ―Multicarrier PWM strategies for multilevel inverters,‖IEEE Trans.
Ind. Electron. , vol. 49, no. 4, pp. 858–867, Aug. 2002.
[8]. O. Lopez, J. Alvarez, J. Doval-Gandoy, and F. D. Freijedo, ―Multilevel multiphase space vector PWM
algorithm,‖ IEEE Trans. Ind. Electron.,vol. 55, no. 5, pp. 1933–1942, May 2008.
[9]. R. Gonzalez, E. Gubia, J. Lopez, and L. Marroyo, ―Transformerless single-phase multilevel-based
photovoltaic inverter,‖ IEEE Trans. Ind. Electron. , vol. 55, no. 7, pp. 2694–2702, Jul. 2008.
[10]. R. H. Baker, ―Electric power converter,‖ U.S. Patent 3 867 643,Feb. 18, 1975.
[11]. C. Rech and J. R. Pinheiro, ―Hybrid multilevel converters: Unified analy-sis and design
considerations,‖ IEEE Trans. Ind. Electron. , vol. 54, no. 2,pp. 1092–1104, Apr. 2007.
[12]. Y. Cheng, C. Qian, M. L. Crow, S. Pekarek, and S. Atcitty, ―A comparison of diode-clamped and
cascaded multilevel converters for a STATCOM with energy storage,‖IEEE Trans. Ind. Electron. , vol.
53, no. 5, pp. 1512– 1521, Oct. 2006
[13]. P. Lezana, J. Rodríguez, and D. A. Oyarzun, ―Cascaded multilevel inverter with regeneration capability
and reduced number of switches,‖ IEEE Trans. Ind. Electron., vol. 55, no. 3, pp. 1059–1066, Mar.
2008.
[14]. A. J. Watson, P. W. Wheeler, and J. C. Clare, ―A complete harmonic elimination approach to dc link
voltage balancing for a cascaded multi-level rectifier,‖ IEEE Trans. Ind. Electron. , vol. 54, no. 6, pp.
2946–2953, Dec. 2007.
[15]. P. Bhagwat and V. R. Stefanovic, ―New versatile commutation circuit for PWM inverters,‖ in Conf.
Rec. IEEE IAS Annu.Meeting , 1980,pp. 774–784.
[16]. G. Gateau, T. A. Meynard, and H. Foch, ―Stacked multicell converter (SMC): Properties and design,‖
in Proc. IEEE Power Electron. Spec.Conf. (PESC), Vancouver, BC, Canada, Jun. 2001, pp. 1583–
1588.
[17]. T. A. Meynard, H. Foch, F. Forest, C. Turpin, F. Richardeau, L. Delmas, G. Gateau, and E. Lefeuvre,
―Multicell converters: Derived topologies,‖IEEE Trans. Ind. Electron. , vol. 49, no. 5, pp. 978–987,
Oct. 2002
[18]. M. Marchesoni and P. Tenca, ―Diode-clamped multilevel converters: A practicable way to balance DC-
link voltages,‖ IEEE Trans. Ind. Electron. ,vol. 49, no. 4, pp. 752–765, Aug. 2002.
[19]. T. A. Meynard, M. Fadel, and N. Aouda, ―Modelling of multilevel converters,‖ IEEE Trans. Ind.
Electron., vol. 44, no. 3, pp. 356–364, Jun. 1997.
14. Solar Panel Using Active Stacked Npc Multi Level Converter
www.irjes.com 33 | Page
[20]. T. A. Meynard, H. Foch, P. Thomas, J. Courault, R. Jakob, and M. Nahrstaedt, ―Multicell converters:
Basic concepts and industry ap-plications,‖ IEEE Trans. Ind. Electron. , vol. 49, no. 5, pp. 955–
964,Oct. 2002.
[21]. G. Gateau, M. Fadel, P. Maussion, R. Bensaid, and T. Meynard, ―Multicell converters: Active control
and observation of flying-capacitor voltages,‖IEEE Trans. Ind. Electron. , vol. 49, no. 5, pp. 998–1008,
Oct. 2002.
[22]. B. McGrath, T. Meynard, and G. Holmes, ―Optimal modulation of flying capacitor and stacked
multicell converters using a state machine decoder,‖IEEE Trans. Power Electron. , vol. 22, no. 2, pp.
508–516, Mar. 2007.
[23]. D. Krug, S. Bernet, S. Fazel, K. Jalili, and M. Malinowski, ―Comparison of 2.3-kV medium-voltage
multilevel converters for industrial medium-voltage drives,‖IEEE Trans. Ind. Electron. , vol. 54, no. 6,
pp. 2979–2992,Dec. 2007.
[24]. J. Sayago, T. Brückner, and S. Bernet, ―How to select the system voltage of MV drives—A comparison
of semiconductor expenses,‖IEEE Trans.
[25]. Ind. Electron. , vol. 55, no. 9, pp. 3381–3390, Sep. 2008.
[26]. T. Brückner and S. Bernet, ―Loss balancing in three-level voltage source inverters applying active NPC
switches,‖ in Proc. IEEE Power Electron.Spec. Conf. , Vancouver, BC, Canada, Jun. 2001, pp. 1135–
1140.