International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This paper is an attempt to develop an Induction Motor Drive System with Multilevel Inverter topology for reduced torque ripple application. A Nine level-cascaded multilevel inverter is developed for the induction motor drive with SVPWM control powered by boost converter fed using solar PV supply. The SVPWM control based implementation of vector control using a multilevel inverter topology needs a multilevel SVPWM control technique, which is implemented in this paper. The Solar power supplied is applied with the MPPT technique and the supplied DC power is fed to the three phase cascaded 9 level multilevel inverter. The vector control of induction motor is carried out using the SVPWM technique on the multilevel topology. The torque ripple reduction in the output is observed and compared with the vector control of induction motor. Matlab based implementation is carried out and the results are tabulated and inferred.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Two parallel single phase rectifiers by using single phase to three phase ind...eSAT Journals
Abstract A single-phase to three-phase drive system composed of two parallel single-phase rectifiers, a three-phase inverter and an induction motor was proposed. The system combines two parallel rectifiers without the use of transformers. The system model and the control strategy, including the PWM technique, have been developed. The complete comparison between the proposed and standard configurations has been carried out in this paper. Compared to the conventional topology, the proposed system permits to reduce the rectifier switch currents, the THD of the grid current with same switching frequency or the switching frequency with same THD of the grid current and to increase the fault tolerance characteristics. In addition, the losses of the proposed system may be lower than that of the conventional counterpart. The initial investment of the proposed system (due to high number of semiconductor devices) cannot be considered a drawback, especially considering the scenario where the cited advantages justify such initial investment. The experimental results have shown that the system is controlled properly, even with transient and occurrence of fault
Grid connected pv system using 9 level flying capacitor multilevel inverterIAEME Publication
This document summarizes a research paper that proposes using a 9-level flying capacitor multilevel inverter to integrate a photovoltaic system into a power grid. A 9-level flying capacitor multilevel inverter can reduce harmonics and total harmonic distortion compared to conventional inverters. The system was simulated in Matlab/Simulink and includes a PV array, boost converter to increase the voltage, and the 9-level flying capacitor multilevel inverter connected to the grid. Key advantages of multilevel inverters are their ability to handle high power applications with reduced switching losses and lower output distortion.
Analysis and simulation of multilevel inverter using multi carrier based pwmIAEME Publication
This document analyzes and simulates a multilevel inverter using multi-carrier based PWM control techniques. It describes a cascaded multilevel inverter topology with separate DC sources for each H-bridge. It discusses phase-shifted and level-shifted carrier based PWM methods and modulation techniques like IPD, POD, and APOD. MATLAB Simulink models are used to simulate 5-level and 7-level inverters using phase-shifted and level-shifted PWM. Total harmonic distortion results show that POD PWM provides the lowest distortion.
Control of inverters to support bidirectional power flow in grid connected sy...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Nowadays power electronics circuits are embedded to most of electrical application areas. This approached offers a great control mechanism with simple and easy circuit configuration. Switched Reluctance Motor (SRM) is one of the most recent apparatus which draws a great number of researchers’ interests. Previously several attempts are made to use the power converters as driver for SRM such as Voltage Source Inverter (VSI) and bridge converters. This paper presents an analysis study of three level inverter to control the SRM. The inverter is controlled using space vector modulation SVM. The aim of this paper is to report the use the multilevel inverter to be fed into the SRM. The implementation of the multilevel inverter is abl to reduce the Total Harmonics Distortion (THD). Performance comparison are made between the multilevel and previous power electronics circuits that applied to the SRM. The simulation results have been conducted by MATLAB/SIMULINK software.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This paper is an attempt to develop an Induction Motor Drive System with Multilevel Inverter topology for reduced torque ripple application. A Nine level-cascaded multilevel inverter is developed for the induction motor drive with SVPWM control powered by boost converter fed using solar PV supply. The SVPWM control based implementation of vector control using a multilevel inverter topology needs a multilevel SVPWM control technique, which is implemented in this paper. The Solar power supplied is applied with the MPPT technique and the supplied DC power is fed to the three phase cascaded 9 level multilevel inverter. The vector control of induction motor is carried out using the SVPWM technique on the multilevel topology. The torque ripple reduction in the output is observed and compared with the vector control of induction motor. Matlab based implementation is carried out and the results are tabulated and inferred.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Two parallel single phase rectifiers by using single phase to three phase ind...eSAT Journals
Abstract A single-phase to three-phase drive system composed of two parallel single-phase rectifiers, a three-phase inverter and an induction motor was proposed. The system combines two parallel rectifiers without the use of transformers. The system model and the control strategy, including the PWM technique, have been developed. The complete comparison between the proposed and standard configurations has been carried out in this paper. Compared to the conventional topology, the proposed system permits to reduce the rectifier switch currents, the THD of the grid current with same switching frequency or the switching frequency with same THD of the grid current and to increase the fault tolerance characteristics. In addition, the losses of the proposed system may be lower than that of the conventional counterpart. The initial investment of the proposed system (due to high number of semiconductor devices) cannot be considered a drawback, especially considering the scenario where the cited advantages justify such initial investment. The experimental results have shown that the system is controlled properly, even with transient and occurrence of fault
Grid connected pv system using 9 level flying capacitor multilevel inverterIAEME Publication
This document summarizes a research paper that proposes using a 9-level flying capacitor multilevel inverter to integrate a photovoltaic system into a power grid. A 9-level flying capacitor multilevel inverter can reduce harmonics and total harmonic distortion compared to conventional inverters. The system was simulated in Matlab/Simulink and includes a PV array, boost converter to increase the voltage, and the 9-level flying capacitor multilevel inverter connected to the grid. Key advantages of multilevel inverters are their ability to handle high power applications with reduced switching losses and lower output distortion.
Analysis and simulation of multilevel inverter using multi carrier based pwmIAEME Publication
This document analyzes and simulates a multilevel inverter using multi-carrier based PWM control techniques. It describes a cascaded multilevel inverter topology with separate DC sources for each H-bridge. It discusses phase-shifted and level-shifted carrier based PWM methods and modulation techniques like IPD, POD, and APOD. MATLAB Simulink models are used to simulate 5-level and 7-level inverters using phase-shifted and level-shifted PWM. Total harmonic distortion results show that POD PWM provides the lowest distortion.
Control of inverters to support bidirectional power flow in grid connected sy...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Nowadays power electronics circuits are embedded to most of electrical application areas. This approached offers a great control mechanism with simple and easy circuit configuration. Switched Reluctance Motor (SRM) is one of the most recent apparatus which draws a great number of researchers’ interests. Previously several attempts are made to use the power converters as driver for SRM such as Voltage Source Inverter (VSI) and bridge converters. This paper presents an analysis study of three level inverter to control the SRM. The inverter is controlled using space vector modulation SVM. The aim of this paper is to report the use the multilevel inverter to be fed into the SRM. The implementation of the multilevel inverter is abl to reduce the Total Harmonics Distortion (THD). Performance comparison are made between the multilevel and previous power electronics circuits that applied to the SRM. The simulation results have been conducted by MATLAB/SIMULINK software.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A comparative study of cascaded h bridge and reversing voltage multilevel inv...IAEME Publication
This document compares a cascaded H-bridge multilevel inverter topology to a proposed reversing voltage multilevel inverter topology. The cascaded H-bridge requires more components as the number of levels increases, making it less reliable. The proposed reversing voltage topology separates output voltage generation into level generation and polarity generation parts, requiring fewer switches. Specifically, a 7-level example of each topology is compared in terms of total harmonic distortion and number of components. The proposed topology is shown to require fewer components and produce lower THD than the cascaded H-bridge topology.
Commanding Doubly-Fed Induction Generator (DFIG) to Decouple Active and React...IOSR Journals
This document analyzes the steady-state characteristics of a wind energy conversion system (WECS) using a doubly fed induction generator (DFIG) through MATLAB simulation. The simulation examines various DFIG operating characteristics including torque-speed curves and how active and reactive power outputs are affected by changes in the rotor voltage. Key findings are that adjusting the rotor voltage can shift the DFIG's operating range and expand its torque/power capabilities, and can also influence whether the generator absorbs or produces reactive power from the grid.
One of the preferred choices of electronic power conversion for high power applications are multilevel inverters topologies finding increased attention in industry. Cascaded H-Bridge multilevel inverter is one of these topologies reaching the higher output voltage, power level and higher reliability due to its modular topology. Level Shifted Carrier Pulse Width Modulation (LSCPWM) and Phase Shifted Carrier Pulse Width Modulation are used generally for switching cascaded H-bridge (CHB) multilevel inverters. This paper compares LSCPWM and PSCPWM in terms of total harmonics distortion (THD) and output voltage among inverter cells. Simulation for 21-level CHB inverter is carried out in MATLAB/SIMULINK and simulation results are presented.
An Improved Single Phase Transformer less Inverter Topology for Cost Effecti...IJMER
In grid connected PV systems, the elimination of isolation transformer introduces common
mode leakage current due to the parasitic capacitance between PV panels and the ground. The common
mode leakage current reduces the efficiency of power conversion stage, affects the quality of grid
current, deteriorate the electric magnetic compatibility and give rise to various safety threats. In order
to eliminate the leakage current, an improved transformer less topology with virtual DC bus concept is
proposed here. By connecting the grid neutral line directly to the negative pole of the DC bus, the stray
capacitance between the PV panels and the ground is bypassed. The topology consists of only five power
switches, two capacitors and the filter section. Therefore, the power electronics cost can be curtailed.
This advanced topology can be modulated with the sinusoidal pulse width modulation (SPWM) to reduce
the output current ripple. The simulation result of the proposed topology using MATLAB/SIMULINK is
presented.
Grid-Connection Control and Simulation of PMSG Wind Power System Based on Mul...ijsrd.com
This dissertation proposes a wind energy conversion system is composed of a wind turbine PMSG, a rectifier, and an inverter. The wind turbine PMSG transforms the mechanical power from the wind into the electrical power, while the rectifier converts the AC power into DC power and controls the speed of the PMSG. The controllable inverter helps in converting the DC power to variable frequency and magnitude AC power. With the voltage oriented control, the inverter also possesses the ability to control the active and reactive powers injected into the grid. Multilevel inerter is used to step up the voltage and to reduce the THD. Here nine level and eleven level inverter are used and the voltage increases and THD reduces from 12.87 % to 7.46 %. Active and reactive power is controlled dc stabilization and the reactive power is near to unity Here PI controller is used to control the inverter output rms voltage and LC filter is used to remove the harmonics available in the system.
SIMULATION AND ANALYSIS OF PERMANENT MAGNET SYNCHRONOUS GENERATOR FOR RENEWAB...IAEME Publication
This paper deals with the simulation of dynamic model of permanent magnet synchronous generator (PMSG) in D-Q axes of the rotor rotating reference frame. The iron core losses and stray load losses of the machine are taken into account. The iron core losses are represented by iron core resistance connected in parallel with magnetizing inductance and then reflected into the stator side as a voltage drop to prevent increasing the number of differential equations in the model. The modified equivalent circuit can deal with all machine parameters without losing the accuracy of generator performance calculations. The modified equivalent circuit can be used as an efficient tool for analysis, design, and vector control algorithm of this type of generator, especially in renewable energy utilization. The model is executed by Matlab Simulink and very good results are obtained and compared with the results of the experimental model to display the validity and accuracy of the proposed dynamic model.
Hydraulics now a days is a very distinguished area which has lot of major challenges often came in its
progress due to the realistic changes affecting on applicable working fluid viz. Water. Most occasions,
Water can be easily available but in certain times it may be scarce also. The available water vary according
to its properties. It exists in normal conditions as well as salty or hardy due to deposits. Majority of Water
is contaminated with minerals, dust or dirt. Often pure water which may be acidic or alkaline can be used
for making discharges through the Turbines
A New Topology for High Level Hybrid Cascaded Multilevel Inverter Motor Drive...IOSR Journals
1) The document proposes a new hybrid cascaded multilevel inverter topology for motor drives that interfaces both DC sources and capacitor energy storage.
2) In the proposed topology, the capacitor is controlled to provide reactive power compensation and cancel lower order harmonics, while the main converter supplies real power with reduced switching losses.
3) The topology can also be modified such that the capacitor energy storage provides both reactive power compensation and real power support during acceleration and braking, absorbing regenerative energy.
This document presents a comparison of different carrier-based pulse width modulation (PWM) strategies for controlling a five-level Z-source diode-clamped inverter. It first provides background on multilevel inverters and Z-source inverters. It then describes the operating principles of the Z-source inverter and equations for its output voltage. Simple boost control is presented as the control method. Three carrier-based PWM strategies - alternative phase opposition disposition, phase opposition disposition, and phase disposition - are described and their performance is evaluated through MATLAB simulations. The results show that alternative phase opposition disposition provides the highest output voltage boost but also the highest total harmonic distortion, while phase disposition has the lowest boost but also the lowest harmonic
This document summarizes a paper that describes the simulation and control of a doubly fed induction generator (DFIG) using artificial neural networks. The DFIG is a type of induction generator that is widely used in wind power generation because it allows variable speed operation while only requiring a power converter rated at 25-30% of the generator rating. The paper presents the mathematical model of the DFIG in the d-q reference frame and describes how to control the rotor voltages using PI and ANN controllers to maintain a constant terminal voltage. Simulation results verify that the model meets the requirements of a variable speed constant frequency wind energy conversion system.
11.seven level modified cascaded inverter for induction motor drive applicationsAlexander Decker
1) The document presents a modified cascaded multilevel inverter topology for induction motor drive applications that reduces the number of switches compared to conventional designs.
2) The proposed topology uses 7 switches and 3 diodes to generate 7 voltage levels, whereas conventional designs require 12 switches. This reduces switching losses, cost, and complexity.
3) Simulation and experimental results show the proposed design can generate 7 voltage levels and drive an induction motor, while achieving lower total harmonic distortion of 11.98% compared to conventional designs.
6.[36 45]seven level modified cascaded inverter for induction motor drive app...Alexander Decker
1) The document presents a modified cascaded multilevel inverter topology for induction motor drive applications that reduces the number of switches compared to conventional designs.
2) The proposed topology uses 7 switches and 3 diodes to generate 7 voltage levels, whereas conventional designs require 12 switches. This reduces switching losses, cost, and complexity.
3) Simulation and experimental results show the proposed design can generate 7 voltage levels to drive an induction motor. FFT analysis shows lower total harmonic distortion compared to conventional designs.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Single phase h6 transformerless inverter with a simple boost converter for pv...eSAT Journals
Abstract
Inverters with transformers of conventional type, connected in PV grid-tied generation systems have now being replaced by transformerless inverters due to various reasons such as reduction in size, weight and cost, improvement in efficiency etc. Transformerless inverters cause a number of technical challenges in grid-connected PV systems, among which flow of leakage currents is a major problem. This leakage currents that flows between the parasitic capacitance of PV array and the grid has to be eliminated, which otherwise leads to serious safety problems. This paper deals with an H6 transformerless full- bridge inverter topology with low leakage currents that can be used in PV grid – tied applications. The operation modes for the proposed topology are discussed in this paper. A closed loop has been developed for maintaining the voltage constant at the grid side irrespective of changes in the input voltage. Aforementioned transformerless topology is simulated that validates the effectiveness of the converter. Keywords: Common-mode voltage, grid-connected inverter, leakage current, photovoltaic (PV), transformerless inverter.
The document summarizes a new converter topology called a phase shifted dual half bridge converter. Two key advantages of this topology are:
1) It can achieve zero voltage switching over a wide load range by operating the two half bridges in a phase shifted manner at 50% duty cycle.
2) It eliminates circulating current that is normally present in full bridge topologies by combining the outputs of the two half bridges with 180 degree phase offset.
The converter was designed with a power rating of 1kW and simulated in PSIM software, demonstrating the benefits of wide ZVS range and no circulating current.
Design and Simulation of transformer less Single Phase Photovoltaic Inverter ...IOSR Journals
This document presents the simulation results of a single-phase photovoltaic inverter without a transformer or batteries. A boost converter raises the voltage from the PV module to the desired level. An inverter with PWM switching converts the DC to AC. Simulation in MATLAB/Simulink shows the PV output of 96V and 6.5A is boosted to 320V DC. The inverter produces a 230V AC output at 50Hz with less than 1% THD, eliminating the need for batteries or a transformer. The proposed design aims to directly and efficiently convert solar power to AC without intermediate components to reduce costs.
Hybrid topology of asymmetric cascaded multilevel inverter with renewable ene...Asoka Technologies
This paper presents a binary topology of Multimodule level inverters produce a staircase output voltage from renewable DC voltage sources. The MLI (Multi Level Inverter) Requires many number of semiconductor switches is main drawback of multilevel inverters. The MLI can be classified as two method, one is symmetric and another asymmetric converters. In symmetrical multilevel inverter can apply same voltage level to all cascaded circuit, in asymmetric multilevel inverters can be vary input source voltage at each cascaded H-bridge by using binary algorithm. In this paper, a discrete binary topology for multilevel converters is proposed using cascaded sub-multilevel Cells. This sub-multilevel converter can produce sixty three levels of voltage from five discrete DC source. The Total Harmonic Distortions (THD) is minimized by discrete binary topology. The working operation and performance of the proposed multilevel inverters studies has been verified by simulation of using SIMULINK / MA TLAB results.
IMPEDANCE SOURCE INVERTER TOPOLOGIES FOR PHOTOVOLTAIC APPLICATIONS – A REVIEWIAEME Publication
The impedance source inverters can step up the voltage and hence, they are greatly preferred for photovoltaic applications. There are many impedance and quasi impedance network topologies available. The key factor in selection of topology is the amount of voltage gain obtained along with the reduced number components. This paper compares some of the impedance and quasi - impedance source inverter (qZSI) topologies for photovoltaic applications namely, switched coupled inductor qZSI, switched ZSI, enhanced-boost quasi ZSI with continuous and discontinuous source current topologies, enhanced -boost active qZSI, switched-boost ZSI and high gain switched boost inverter. The parameters taken for comparison are voltage gain, boost factor, voltage, and current stresses on the components etc. Based on the comparison, the high gain switched boost ZSI is found to have high voltage gain along with reduced voltage and current stress. The review will be useful for researchers working in impedance source inverter network.
A novel single phase cascaded h-bridge inverter with new cell configuration a...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
The document discusses prototyping and provides examples of different types of prototypes including paper prototypes, digital prototypes, storyboards, role plays, and space prototypes. It explains that prototyping is used to make ideas tangible and test reactions from users in order to gain insights. Prototypes should be iterated on and fail early to push ideas further and save time and money. Both low and high fidelity prototypes are mentioned as ways to test ideas at different stages of the design process.
10 Insightful Quotes On Designing A Better Customer ExperienceYuan Wang
In an ever-changing landscape of one digital disruption after another, companies and organisations are looking for new ways to understand their target markets and engage them better. Increasingly they invest in user experience (UX) and customer experience design (CX) capabilities by working with a specialist UX agency or developing their own UX lab. Some UX practitioners are touting leaner and faster ways of developing customer-centric products and services, via methodologies such as guerilla research, rapid prototyping and Agile UX. Others seek innovation and fulfilment by spending more time in research, being more inclusive, and designing for social goods.
Experience is more than just an interface. It is a relationship, as well as a series of touch points between your brand and your customer. Here are our top 10 highlights and takeaways from the recent UX Australia conference to help you transform your customer experience design.
For full article, continue reading at https://yump.com.au/10-ways-supercharge-customer-experience-design/
http://inarocket.com
Learn BEM fundamentals as fast as possible. What is BEM (Block, element, modifier), BEM syntax, how it works with a real example, etc.
A comparative study of cascaded h bridge and reversing voltage multilevel inv...IAEME Publication
This document compares a cascaded H-bridge multilevel inverter topology to a proposed reversing voltage multilevel inverter topology. The cascaded H-bridge requires more components as the number of levels increases, making it less reliable. The proposed reversing voltage topology separates output voltage generation into level generation and polarity generation parts, requiring fewer switches. Specifically, a 7-level example of each topology is compared in terms of total harmonic distortion and number of components. The proposed topology is shown to require fewer components and produce lower THD than the cascaded H-bridge topology.
Commanding Doubly-Fed Induction Generator (DFIG) to Decouple Active and React...IOSR Journals
This document analyzes the steady-state characteristics of a wind energy conversion system (WECS) using a doubly fed induction generator (DFIG) through MATLAB simulation. The simulation examines various DFIG operating characteristics including torque-speed curves and how active and reactive power outputs are affected by changes in the rotor voltage. Key findings are that adjusting the rotor voltage can shift the DFIG's operating range and expand its torque/power capabilities, and can also influence whether the generator absorbs or produces reactive power from the grid.
One of the preferred choices of electronic power conversion for high power applications are multilevel inverters topologies finding increased attention in industry. Cascaded H-Bridge multilevel inverter is one of these topologies reaching the higher output voltage, power level and higher reliability due to its modular topology. Level Shifted Carrier Pulse Width Modulation (LSCPWM) and Phase Shifted Carrier Pulse Width Modulation are used generally for switching cascaded H-bridge (CHB) multilevel inverters. This paper compares LSCPWM and PSCPWM in terms of total harmonics distortion (THD) and output voltage among inverter cells. Simulation for 21-level CHB inverter is carried out in MATLAB/SIMULINK and simulation results are presented.
An Improved Single Phase Transformer less Inverter Topology for Cost Effecti...IJMER
In grid connected PV systems, the elimination of isolation transformer introduces common
mode leakage current due to the parasitic capacitance between PV panels and the ground. The common
mode leakage current reduces the efficiency of power conversion stage, affects the quality of grid
current, deteriorate the electric magnetic compatibility and give rise to various safety threats. In order
to eliminate the leakage current, an improved transformer less topology with virtual DC bus concept is
proposed here. By connecting the grid neutral line directly to the negative pole of the DC bus, the stray
capacitance between the PV panels and the ground is bypassed. The topology consists of only five power
switches, two capacitors and the filter section. Therefore, the power electronics cost can be curtailed.
This advanced topology can be modulated with the sinusoidal pulse width modulation (SPWM) to reduce
the output current ripple. The simulation result of the proposed topology using MATLAB/SIMULINK is
presented.
Grid-Connection Control and Simulation of PMSG Wind Power System Based on Mul...ijsrd.com
This dissertation proposes a wind energy conversion system is composed of a wind turbine PMSG, a rectifier, and an inverter. The wind turbine PMSG transforms the mechanical power from the wind into the electrical power, while the rectifier converts the AC power into DC power and controls the speed of the PMSG. The controllable inverter helps in converting the DC power to variable frequency and magnitude AC power. With the voltage oriented control, the inverter also possesses the ability to control the active and reactive powers injected into the grid. Multilevel inerter is used to step up the voltage and to reduce the THD. Here nine level and eleven level inverter are used and the voltage increases and THD reduces from 12.87 % to 7.46 %. Active and reactive power is controlled dc stabilization and the reactive power is near to unity Here PI controller is used to control the inverter output rms voltage and LC filter is used to remove the harmonics available in the system.
SIMULATION AND ANALYSIS OF PERMANENT MAGNET SYNCHRONOUS GENERATOR FOR RENEWAB...IAEME Publication
This paper deals with the simulation of dynamic model of permanent magnet synchronous generator (PMSG) in D-Q axes of the rotor rotating reference frame. The iron core losses and stray load losses of the machine are taken into account. The iron core losses are represented by iron core resistance connected in parallel with magnetizing inductance and then reflected into the stator side as a voltage drop to prevent increasing the number of differential equations in the model. The modified equivalent circuit can deal with all machine parameters without losing the accuracy of generator performance calculations. The modified equivalent circuit can be used as an efficient tool for analysis, design, and vector control algorithm of this type of generator, especially in renewable energy utilization. The model is executed by Matlab Simulink and very good results are obtained and compared with the results of the experimental model to display the validity and accuracy of the proposed dynamic model.
Hydraulics now a days is a very distinguished area which has lot of major challenges often came in its
progress due to the realistic changes affecting on applicable working fluid viz. Water. Most occasions,
Water can be easily available but in certain times it may be scarce also. The available water vary according
to its properties. It exists in normal conditions as well as salty or hardy due to deposits. Majority of Water
is contaminated with minerals, dust or dirt. Often pure water which may be acidic or alkaline can be used
for making discharges through the Turbines
A New Topology for High Level Hybrid Cascaded Multilevel Inverter Motor Drive...IOSR Journals
1) The document proposes a new hybrid cascaded multilevel inverter topology for motor drives that interfaces both DC sources and capacitor energy storage.
2) In the proposed topology, the capacitor is controlled to provide reactive power compensation and cancel lower order harmonics, while the main converter supplies real power with reduced switching losses.
3) The topology can also be modified such that the capacitor energy storage provides both reactive power compensation and real power support during acceleration and braking, absorbing regenerative energy.
This document presents a comparison of different carrier-based pulse width modulation (PWM) strategies for controlling a five-level Z-source diode-clamped inverter. It first provides background on multilevel inverters and Z-source inverters. It then describes the operating principles of the Z-source inverter and equations for its output voltage. Simple boost control is presented as the control method. Three carrier-based PWM strategies - alternative phase opposition disposition, phase opposition disposition, and phase disposition - are described and their performance is evaluated through MATLAB simulations. The results show that alternative phase opposition disposition provides the highest output voltage boost but also the highest total harmonic distortion, while phase disposition has the lowest boost but also the lowest harmonic
This document summarizes a paper that describes the simulation and control of a doubly fed induction generator (DFIG) using artificial neural networks. The DFIG is a type of induction generator that is widely used in wind power generation because it allows variable speed operation while only requiring a power converter rated at 25-30% of the generator rating. The paper presents the mathematical model of the DFIG in the d-q reference frame and describes how to control the rotor voltages using PI and ANN controllers to maintain a constant terminal voltage. Simulation results verify that the model meets the requirements of a variable speed constant frequency wind energy conversion system.
11.seven level modified cascaded inverter for induction motor drive applicationsAlexander Decker
1) The document presents a modified cascaded multilevel inverter topology for induction motor drive applications that reduces the number of switches compared to conventional designs.
2) The proposed topology uses 7 switches and 3 diodes to generate 7 voltage levels, whereas conventional designs require 12 switches. This reduces switching losses, cost, and complexity.
3) Simulation and experimental results show the proposed design can generate 7 voltage levels and drive an induction motor, while achieving lower total harmonic distortion of 11.98% compared to conventional designs.
6.[36 45]seven level modified cascaded inverter for induction motor drive app...Alexander Decker
1) The document presents a modified cascaded multilevel inverter topology for induction motor drive applications that reduces the number of switches compared to conventional designs.
2) The proposed topology uses 7 switches and 3 diodes to generate 7 voltage levels, whereas conventional designs require 12 switches. This reduces switching losses, cost, and complexity.
3) Simulation and experimental results show the proposed design can generate 7 voltage levels to drive an induction motor. FFT analysis shows lower total harmonic distortion compared to conventional designs.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Single phase h6 transformerless inverter with a simple boost converter for pv...eSAT Journals
Abstract
Inverters with transformers of conventional type, connected in PV grid-tied generation systems have now being replaced by transformerless inverters due to various reasons such as reduction in size, weight and cost, improvement in efficiency etc. Transformerless inverters cause a number of technical challenges in grid-connected PV systems, among which flow of leakage currents is a major problem. This leakage currents that flows between the parasitic capacitance of PV array and the grid has to be eliminated, which otherwise leads to serious safety problems. This paper deals with an H6 transformerless full- bridge inverter topology with low leakage currents that can be used in PV grid – tied applications. The operation modes for the proposed topology are discussed in this paper. A closed loop has been developed for maintaining the voltage constant at the grid side irrespective of changes in the input voltage. Aforementioned transformerless topology is simulated that validates the effectiveness of the converter. Keywords: Common-mode voltage, grid-connected inverter, leakage current, photovoltaic (PV), transformerless inverter.
The document summarizes a new converter topology called a phase shifted dual half bridge converter. Two key advantages of this topology are:
1) It can achieve zero voltage switching over a wide load range by operating the two half bridges in a phase shifted manner at 50% duty cycle.
2) It eliminates circulating current that is normally present in full bridge topologies by combining the outputs of the two half bridges with 180 degree phase offset.
The converter was designed with a power rating of 1kW and simulated in PSIM software, demonstrating the benefits of wide ZVS range and no circulating current.
Design and Simulation of transformer less Single Phase Photovoltaic Inverter ...IOSR Journals
This document presents the simulation results of a single-phase photovoltaic inverter without a transformer or batteries. A boost converter raises the voltage from the PV module to the desired level. An inverter with PWM switching converts the DC to AC. Simulation in MATLAB/Simulink shows the PV output of 96V and 6.5A is boosted to 320V DC. The inverter produces a 230V AC output at 50Hz with less than 1% THD, eliminating the need for batteries or a transformer. The proposed design aims to directly and efficiently convert solar power to AC without intermediate components to reduce costs.
Hybrid topology of asymmetric cascaded multilevel inverter with renewable ene...Asoka Technologies
This paper presents a binary topology of Multimodule level inverters produce a staircase output voltage from renewable DC voltage sources. The MLI (Multi Level Inverter) Requires many number of semiconductor switches is main drawback of multilevel inverters. The MLI can be classified as two method, one is symmetric and another asymmetric converters. In symmetrical multilevel inverter can apply same voltage level to all cascaded circuit, in asymmetric multilevel inverters can be vary input source voltage at each cascaded H-bridge by using binary algorithm. In this paper, a discrete binary topology for multilevel converters is proposed using cascaded sub-multilevel Cells. This sub-multilevel converter can produce sixty three levels of voltage from five discrete DC source. The Total Harmonic Distortions (THD) is minimized by discrete binary topology. The working operation and performance of the proposed multilevel inverters studies has been verified by simulation of using SIMULINK / MA TLAB results.
IMPEDANCE SOURCE INVERTER TOPOLOGIES FOR PHOTOVOLTAIC APPLICATIONS – A REVIEWIAEME Publication
The impedance source inverters can step up the voltage and hence, they are greatly preferred for photovoltaic applications. There are many impedance and quasi impedance network topologies available. The key factor in selection of topology is the amount of voltage gain obtained along with the reduced number components. This paper compares some of the impedance and quasi - impedance source inverter (qZSI) topologies for photovoltaic applications namely, switched coupled inductor qZSI, switched ZSI, enhanced-boost quasi ZSI with continuous and discontinuous source current topologies, enhanced -boost active qZSI, switched-boost ZSI and high gain switched boost inverter. The parameters taken for comparison are voltage gain, boost factor, voltage, and current stresses on the components etc. Based on the comparison, the high gain switched boost ZSI is found to have high voltage gain along with reduced voltage and current stress. The review will be useful for researchers working in impedance source inverter network.
A novel single phase cascaded h-bridge inverter with new cell configuration a...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
The document discusses prototyping and provides examples of different types of prototypes including paper prototypes, digital prototypes, storyboards, role plays, and space prototypes. It explains that prototyping is used to make ideas tangible and test reactions from users in order to gain insights. Prototypes should be iterated on and fail early to push ideas further and save time and money. Both low and high fidelity prototypes are mentioned as ways to test ideas at different stages of the design process.
10 Insightful Quotes On Designing A Better Customer ExperienceYuan Wang
In an ever-changing landscape of one digital disruption after another, companies and organisations are looking for new ways to understand their target markets and engage them better. Increasingly they invest in user experience (UX) and customer experience design (CX) capabilities by working with a specialist UX agency or developing their own UX lab. Some UX practitioners are touting leaner and faster ways of developing customer-centric products and services, via methodologies such as guerilla research, rapid prototyping and Agile UX. Others seek innovation and fulfilment by spending more time in research, being more inclusive, and designing for social goods.
Experience is more than just an interface. It is a relationship, as well as a series of touch points between your brand and your customer. Here are our top 10 highlights and takeaways from the recent UX Australia conference to help you transform your customer experience design.
For full article, continue reading at https://yump.com.au/10-ways-supercharge-customer-experience-design/
http://inarocket.com
Learn BEM fundamentals as fast as possible. What is BEM (Block, element, modifier), BEM syntax, how it works with a real example, etc.
How to Build a Dynamic Social Media PlanPost Planner
Stop guessing and wasting your time on networks and strategies that don’t work!
Join Rebekah Radice and Katie Lance to learn how to optimize your social networks, the best kept secrets for hot content, top time management tools, and much more!
Watch the replay here: bit.ly/socialmedia-plan
Lightning Talk #9: How UX and Data Storytelling Can Shape Policy by Mika Aldabaux singapore
How can we take UX and Data Storytelling out of the tech context and use them to change the way government behaves?
Showcasing the truth is the highest goal of data storytelling. Because the design of a chart can affect the interpretation of data in a major way, one must wield visual tools with care and deliberation. Using quantitative facts to evoke an emotional response is best achieved with the combination of UX and data storytelling.
The document discusses how personalization and dynamic content are becoming increasingly important on websites. It notes that 52% of marketers see content personalization as critical and 75% of consumers like it when brands personalize their content. However, personalization can create issues for search engine optimization as dynamic URLs and content are more difficult for search engines to index than static pages. The document provides tips for SEOs to help address these personalization and SEO challenges, such as using static URLs when possible and submitting accurate sitemaps.
This document summarizes a study of CEO succession events among the largest 100 U.S. corporations between 2005-2015. The study analyzed executives who were passed over for the CEO role ("succession losers") and their subsequent careers. It found that 74% of passed over executives left their companies, with 30% eventually becoming CEOs elsewhere. However, companies led by succession losers saw average stock price declines of 13% over 3 years, compared to gains for companies whose CEO selections remained unchanged. The findings suggest that boards generally identify the most qualified CEO candidates, though differences between internal and external hires complicate comparisons.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Design & Simulation Of 3-Phase, 15-Level Inverter with Reverse Voltage TopologyIJERA Editor
This document describes the design and simulation of a 15-level three-phase inverter with a reverse voltage topology. A new topology is proposed that requires fewer components than existing inverters, particularly at higher voltage levels. This reduces complexity. The 15-level inverter is modeled and simulated in MATLAB. Simulation results show the output voltage waveform, total harmonic distortion within reasonable limits, and voltage and current waveforms. The proposed inverter provides high voltage output with reduced harmonic distortion and lower component count.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Harmonic Analysis of Seven and Nine Level Cascade Multilevel Inverter using M...IAES-IJPEDS
The use of multilevel inverters has become popular in recent years for high- power applications. Multilevel Inverters are power converter systems composed by an array of power semiconductor sources that when properly connected and controlled can generate a multistep voltage waveform with variable and controllable frequency, phase and amplitude. This study deals with the comparison of a 7-level inverter with a 9-level inverter system; the voltage source inverters (VSI) are modelled and simulated using MATLAB Simulink and the results are presented. The test results verify the effectiveness of the proposed strategy in terms of computational efficiency as well as the capability of the inverter to produce very low distorted voltage with low-switching losses. This research aims to extend the knowledge about the performance of different clamped multilevel inverter through harmonic analysis. Simulations results validate up to the mark performance of the mentioned topologies.
THD Analysis of Cascaded Multi level Inverters using different PWM Techniquesijtsrd
Multi level inverters MLI are used in places or industries that require very high voltage and huge current. Multi level inverter topologies have various advantages over single level converters. These advantages are like rise in output voltage, reduction in the total harmonic distortion THD , reduction in electro magnetic interference EMI generation etc. Key attribute of a multi level inverter is the reduction in the voltage stress on each power device. This reduction is due to the use of several levels available on the DC bus. The dawn of multi level inverter topologies have created requirement of various pulse width modulation techniques. In this paper authors have used PWM technique, by which the total harmonic distortion of the multi level inverter is decreased. In this we have also controlled the speed of the induction motor by supplying the power through a multi level inverter. Shilpa Sambhi | Ankit Mittal | Aviral Srivastava | Ayan Mondal | Nitin Varshney ""THD Analysis of Cascaded Multi-level Inverters using different PWM Techniques"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd23984.pdf
Paper URL: https://www.ijtsrd.com/engineering/electronics-and-communication-engineering/23984/thd-analysis-of-cascaded-multi-level-inverters-using-different-pwm-techniques/shilpa-sambhi
Multilevel Inverter using SPWM Technique for AC Power SupplyIJERA Editor
This paper presents two multilevel inverter for AC power supply. The cascaded H bridge topology of multilevel inverter is implemented .The control strategy has been design using SPWM technique. The operation of multilevel inverter is analyzed. The output has controlled and reduction in harmonic and THD. The simulation model has been built in matlab simulink and results are observed.
Design and Optimum Arrangement Of 3-phase Cascade Multilevel Inverter for Con...IOSR Journals
This document summarizes a research paper that investigates using a cascade multilevel inverter to control an induction motor via direct torque control (DTC). It begins by introducing multilevel inverters and their benefits for high power applications. It then describes the cascade H-bridge topology and symmetrical vs asymmetrical configurations. The document outlines DTC for controlling induction motors and discusses extending this technique to multilevel inverters. It presents the torque and flux estimation methods used in DTC as well as the voltage vector selection process. The research aims to optimize DTC for induction motors powered by a cascade multilevel inverter.
A Novel Three Phase Multilevel Inverter with Single DC Link for Induction Mot...IJECEIAES
1) The document presents two configurations of a novel three-phase eleven-level multilevel inverter with a reduced number of switches for induction motor drive applications.
2) Configuration 1 uses separate DC sources for each phase, requiring 24 switches total. Configuration 2 uses a single common DC source for all three phases, also requiring 24 switches.
3) Both configurations are simulated in Matlab/Simulink. Results show the inverter produces a three-phase voltage of 600V peak-to-peak and supplies 50A to an induction motor, driving it at 1400rpm with 10N-m of torque.
SIMULATION AND STUDY OF MULTILEVEL INVERTER (ppt)Arpit Kurel
This document discusses the simulation and study of a multilevel inverter. It aims to simulate a three-phase five-level inverter using MATLAB/Simulink. Multilevel inverters are attractive for medium-voltage high-power applications as they can produce outputs with low distortion at medium voltages. The document reviews literature on multilevel inverters and various topologies. It then discusses objectives of simulating a five-level inverter to reduce harmonics. Simulation results show that a five-level inverter has lower total harmonic distortion and higher efficiency compared to a three-level inverter.
This project aims at using (PD-MCPWM) Phase
disposition multi carrier pulse width modulation technique to
reduce leakage current in a transformerless cascaded multilevel
inverter for PV systems. Advantages of transformerless PV
inverter topology is as follows, simple structure, low weight and
provides higher efficiency , but however this topology provides a
path for the leakage current to flow through the parasitic
capacitance formed between the PV module and the ground.
Modulation technique reduces leakage current with an added
advantage without adding any extra components.
High Proficiency Grid ConnectedPhotovoltaic Power Generation SystemIJRES Journal
Solar energy hasbecomepopular nowadays and desire for clean energy. Since the solar radiation on no occasion remains constant,it keeps on insecure throughout the day. The need of the hour is to distribute a constant voltage to the grid irrespective of the deviation in temperatures and solar insolation. The inverter is designed from a boost converter along with a line frequency. The voltage from the boost converter is fedto the grid through inverter. In this proposed method high efficiency can be achievedby using only one switch functioning at high frequency at a time. The converter uses IGBT and ultra-fast reverse recovery diode. The simulation and experiment results are verified using MATLAB/Simulink software.
This paper deals with the design of cascaded 11 level H- bridge inverter. It includes a comparison between the 11 level H-bridge and T-bridge multilevel inverter. The cascaded inverter of higher level is a very effective and practical solution for reduction of total harmonic distortion (THD).These cascaded multilevel inverter can be used for higher voltage applications with more stability. As the level is increased the output waveform becomes more sinusoidal in nature. The inverter is designed using multicarrier sinusoidal pulse width modulation technique for generating triggering pulses for the semiconductor switches used in the device. Through this paper it will be proved that a cascaded multilevel H-bridge topology has higher efficiency than a T-bridge inverter, as whichever source input voltage is provided since input is equal to the output voltage. In T-bridge inverter, the output obtained is half of the applied input, so efficiency is just half as compared to H-bridge. The output waveform is distorted and has higher THD. The simulation is performed using MATLAB /Simulink 2013 software.
A New Configuration of Asymmetric Multilevel Converter to Maximize the Number...IJMTST Journal
The multilevel converters are increasingly becoming popular because of its high power applications. This research paper describes about the new structure that can produce increased number of output voltage waveform using a single source and reduced number of power electronic components. In designing a multilevel converter, the power electronic switches play a very imperative role as it describes the installation area, cost, configuration complexity and may more things that play a significant role while designing. The prime function of multilevel converter is to abolish total harmonic distortion and to incorporate desired ac voltage from several separate dc sources. Each level consists of H-Bridge converter units. High efficiency, high voltage capability, lower switching losses are its prime advantages. A multilevel power converter structure can be introduced as an alternative in medium voltage and high power situations. This structure not only achieves high power ratings but also empower the use of renewable energy sources. It finds its basic application in adjustable speed drives, Static Compensator (STATCOM).
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Wind Energy Conversion System Using PMSG with T-Source Three Phase Matrix Con...IJTET Journal
This document presents a wind energy conversion system using a permanent magnet synchronous generator (PMSG) connected to a T-source three-phase matrix converter. The system aims to efficiently harness wind power and deliver it to a load. A PMSG is connected to a three-phase diode rectifier and input capacitors, with the output fed to a T-source network and three-phase matrix converter. The converter can boost output voltage regardless of input voltage and regulate it through shoot-through control. MATLAB/Simulink models are developed and simulations show the converter produces controlled output voltage and current waveforms to power the load efficiently with fewer components than traditional converter topologies.
A Comparison Analysis of Unipolar and Bipolar Switching modulated Cascade H-B...IJERA Editor
This paper discusses controlling of cascaded H-bridge multi inverter with sinusoidal modulation based PWM methods. Multi-level inverters are used to reduce the THD in the output wave form without reduction in power output of inverter. Increase in voltage level in the output voltage of an inverter increases numbers of components to be used in inverter configuration. This in turn increases the switching loss. But results in good harmonic distortion and provide better quality fundamental wave. Carrier based PWM schemes are used for control of switching operation of multi-level inverters. Many kinds of PWM schemes are available to control inverter switches. In this paper uniploar carrier based PWM, bipolar carrier based PWM schemes are considered for generation of carrier signals. The carrier signals thus generated are compared with sinusoidal and third harmonic based sinusoidal modulating signals for production of switching Pulses. Switching schemes are designed for a 3 Phase 3, 5, 7, 9 and 11 Level inverters. The proposed switching schemes are applied to Cascaded H-Bridge Multi Level inverters. The circuit is simulated with MATLAB Simulink environment for verification of total harmonic distortion.
This document summarizes research on carrier shifting algorithms for mitigating circulating current in a diode-clamped multilevel inverter (MLI) driving an induction motor. It proposes phase shift (PS), phase disposition (PD), and phase opposition disposition (POD) carrier shifting pulse width modulation (PWM) techniques to reduce circulating current within each inverter phase leg. Simulation and experimental results show that the PD technique provides the best performance in terms of reducing circulating current and harmonics compared to PS and POD. The PD algorithm can reduce circulating current to ±Idc/6, whereas PS only reduces to ±Idc/2 and POD to ±Idc/3.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document summarizes a research paper that proposes a dual inverter topology for open-ended winding induction motor drives. The topology uses a single DC source and a floating capacitor bank to achieve multi-level output voltages. Switching combinations are used to control the voltage of the floating capacitor bank and charge it to half the main DC link voltage. Simulation and experimental results demonstrate the motor drive operating with open-loop V/f control and closed-loop field oriented control.
Simulation of 3-phase matrix converter using space vector modulationIJECEIAES
This paper illustrates the simulation of 3-phase matrix converter using Space Vector Modulation (SVM). Variable AC output voltage engendered using matrix converter with bidirectional power switches controlled by appropriate switching pulse. The conventional PWM converter engenders switching common mode voltage across the load system terminals, which cause to common mode current and its leads to bearing failure in load drive. These problems can be rectified using SVM and which minimize the effect on the harmonic fluctuation in AC output voltage and stress on the power switch is reduced using bidirectional switch for proposed 3-phase matrix converter. The simulation results have been presented to validate the proposed system using matlab / simulink.
In the rapidly evolving landscape of technologies, XML continues to play a vital role in structuring, storing, and transporting data across diverse systems. The recent advancements in artificial intelligence (AI) present new methodologies for enhancing XML development workflows, introducing efficiency, automation, and intelligent capabilities. This presentation will outline the scope and perspective of utilizing AI in XML development. The potential benefits and the possible pitfalls will be highlighted, providing a balanced view of the subject.
We will explore the capabilities of AI in understanding XML markup languages and autonomously creating structured XML content. Additionally, we will examine the capacity of AI to enrich plain text with appropriate XML markup. Practical examples and methodological guidelines will be provided to elucidate how AI can be effectively prompted to interpret and generate accurate XML markup.
Further emphasis will be placed on the role of AI in developing XSLT, or schemas such as XSD and Schematron. We will address the techniques and strategies adopted to create prompts for generating code, explaining code, or refactoring the code, and the results achieved.
The discussion will extend to how AI can be used to transform XML content. In particular, the focus will be on the use of AI XPath extension functions in XSLT, Schematron, Schematron Quick Fixes, or for XML content refactoring.
The presentation aims to deliver a comprehensive overview of AI usage in XML development, providing attendees with the necessary knowledge to make informed decisions. Whether you’re at the early stages of adopting AI or considering integrating it in advanced XML development, this presentation will cover all levels of expertise.
By highlighting the potential advantages and challenges of integrating AI with XML development tools and languages, the presentation seeks to inspire thoughtful conversation around the future of XML development. We’ll not only delve into the technical aspects of AI-powered XML development but also discuss practical implications and possible future directions.
Fueling AI with Great Data with Airbyte WebinarZilliz
This talk will focus on how to collect data from a variety of sources, leveraging this data for RAG and other GenAI use cases, and finally charting your course to productionalization.
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
Ivanti’s Patch Tuesday breakdown goes beyond patching your applications and brings you the intelligence and guidance needed to prioritize where to focus your attention first. Catch early analysis on our Ivanti blog, then join industry expert Chris Goettl for the Patch Tuesday Webinar Event. There we’ll do a deep dive into each of the bulletins and give guidance on the risks associated with the newly-identified vulnerabilities.
5th LF Energy Power Grid Model Meet-up SlidesDanBrown980551
5th Power Grid Model Meet-up
It is with great pleasure that we extend to you an invitation to the 5th Power Grid Model Meet-up, scheduled for 6th June 2024. This event will adopt a hybrid format, allowing participants to join us either through an online Mircosoft Teams session or in person at TU/e located at Den Dolech 2, Eindhoven, Netherlands. The meet-up will be hosted by Eindhoven University of Technology (TU/e), a research university specializing in engineering science & technology.
Power Grid Model
The global energy transition is placing new and unprecedented demands on Distribution System Operators (DSOs). Alongside upgrades to grid capacity, processes such as digitization, capacity optimization, and congestion management are becoming vital for delivering reliable services.
Power Grid Model is an open source project from Linux Foundation Energy and provides a calculation engine that is increasingly essential for DSOs. It offers a standards-based foundation enabling real-time power systems analysis, simulations of electrical power grids, and sophisticated what-if analysis. In addition, it enables in-depth studies and analysis of the electrical power grid’s behavior and performance. This comprehensive model incorporates essential factors such as power generation capacity, electrical losses, voltage levels, power flows, and system stability.
Power Grid Model is currently being applied in a wide variety of use cases, including grid planning, expansion, reliability, and congestion studies. It can also help in analyzing the impact of renewable energy integration, assessing the effects of disturbances or faults, and developing strategies for grid control and optimization.
What to expect
For the upcoming meetup we are organizing, we have an exciting lineup of activities planned:
-Insightful presentations covering two practical applications of the Power Grid Model.
-An update on the latest advancements in Power Grid -Model technology during the first and second quarters of 2024.
-An interactive brainstorming session to discuss and propose new feature requests.
-An opportunity to connect with fellow Power Grid Model enthusiasts and users.
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und überflüssigen Konten
- Wie funktionieren CCB- und CCX-Lizenzen wirklich?
- Verstehen des DLAU-Tools und wie man es am besten nutzt
- Tipps für häufige Problembereiche, wie z. B. Team-Postfächer, Funktions-/Testbenutzer usw.
- Praxisbeispiele und Best Practices zum sofortigen Umsetzen
Introduction of Cybersecurity with OSS at Code Europe 2024Hiroshi SHIBATA
I develop the Ruby programming language, RubyGems, and Bundler, which are package managers for Ruby. Today, I will introduce how to enhance the security of your application using open-source software (OSS) examples from Ruby and RubyGems.
The first topic is CVE (Common Vulnerabilities and Exposures). I have published CVEs many times. But what exactly is a CVE? I'll provide a basic understanding of CVEs and explain how to detect and handle vulnerabilities in OSS.
Next, let's discuss package managers. Package managers play a critical role in the OSS ecosystem. I'll explain how to manage library dependencies in your application.
I'll share insights into how the Ruby and RubyGems core team works to keep our ecosystem safe. By the end of this talk, you'll have a better understanding of how to safeguard your code.
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
Have you ever been confused by the myriad of choices offered by AWS for hosting a website or an API?
Lambda, Elastic Beanstalk, Lightsail, Amplify, S3 (and more!) can each host websites + APIs. But which one should we choose?
Which one is cheapest? Which one is fastest? Which one will scale to meet our needs?
Join me in this session as we dive into each AWS hosting service to determine which one is best for your scenario and explain why!
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
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.
Generating privacy-protected synthetic data using Secludy and MilvusZilliz
During this demo, the founders of Secludy will demonstrate how their system utilizes Milvus to store and manipulate embeddings for generating privacy-protected synthetic data. Their approach not only maintains the confidentiality of the original data but also enhances the utility and scalability of LLMs under privacy constraints. Attendees, including machine learning engineers, data scientists, and data managers, will witness first-hand how Secludy's integration with Milvus empowers organizations to harness the power of LLMs securely and efficiently.
Digital Marketing Trends in 2024 | Guide for Staying AheadWask
https://www.wask.co/ebooks/digital-marketing-trends-in-2024
Feeling lost in the digital marketing whirlwind of 2024? Technology is changing, consumer habits are evolving, and staying ahead of the curve feels like a never-ending pursuit. This e-book is your compass. Dive into actionable insights to handle the complexities of modern marketing. From hyper-personalization to the power of user-generated content, learn how to build long-term relationships with your audience and unlock the secrets to success in the ever-shifting digital landscape.
How to Get CNIC Information System with Paksim Ga.pptxdanishmna97
Pakdata Cf is a groundbreaking system designed to streamline and facilitate access to CNIC information. This innovative platform leverages advanced technology to provide users with efficient and secure access to their CNIC details.
Cosa hanno in comune un mattoncino Lego e la backdoor XZ?Speck&Tech
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1. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.863-872
863 | P a g e
Power Flow Control In Induction Motor By Using Assymmetrical
Multilevel Inverter
Miss Vani Mishra, Mrs.Paramjeet Kaur
Assistant Professor,at NRI College,RGPV University,Bhopal))
ABSTRACT
The Assymetrical multilevel inverter
topology is used for the optimization of levels
with a mimimum no. of voltage sources. It is
used where medium voltage and higher power is
required.There are three or four H-bridge of
single phase inverter (consist of MOSFET or
Optocoupler)connected to Induction motor.All
H-Bridges are working with different votage
sources bases on the G.P ratio(2or3).A
multilevel inverter is more advantageous in
comparison with a conventional two-level
converter that uses high switching frequency
pulse width modulation(PWM).The increase in
the number of level in multilevel inverter
reduces the total harmonic distortion
(THD),common mode voltages,the output filters
and the switching losses and hence power flow
can be controlled by providing smooth a.c sine
wave to the induction motor to mainly prevent
the reduction of the efficiency of the motor due
to harmonics which are present in normal
power supply.But in multilevel there are also
some limitations if we will go for higher levels
i.e.beyond 27 level that we will also see here in
detail description by the results of simulation
done on MATLAB7.10.
Keywords- Assymetrical multilevel inverter,
MOSFET, Optocoupler, Induction motor,H-
Bridge(consist of MOSFET),G.P ratio,
Conventional two-level converter, PWM,THD,
common mode voltages,output filters, switching
losses, harmonics, ac sine wave, efficiency,
simulation
1. INTRODUCTION
Numerous industrial applications have
begun to require higher power application in recent
years.Some mediun voltage motor drives and utility
applications require medium voltage motor drives
and utility applications require medium voltage and
megawatt power level.For a medium voltage grid,it
is troublesome to connect only one power
semiconductor switch directly.As a result a
multilevel power converter structure has been
introduced as an alternative in high power and
medium voltage situation.A multilevel converter
not only achieves high power ratings,but also
enables the use of renewable energy
sources.Renewable energy sources such as
photovoltaic,wind and fuel cells can be easily
interfaced to a multilevel converter system for a
high power application.
The concept of multilevel converters has
been introduced since 1975.The elementary
concept of multilevel converter to achieve higher
power is to use a series of power semiconductor
switches with several lower voltage d.c sources to
perform the power conversion by synthesizing a
stair case voltage waveform. Capacitors, batteries
and renewable energy voltage sources can be used
as the multiple d.c voltage sources.
Multilevel inverter topologies can work at
higher voltage and higher power than conventional
two level converter.A multilevel converter has
several advantage over a conventional two level
converter that uses high switching frequency pulse
width modulation(PWM).
The attractive features of a multilevel converter can
be briefly summarized as follows:
1) Staircase waveform quality:
Multilevel converters not only can generate the
output voltage with very low distortion ,but
also can reduce the dv/dt stresses ;therefore
electromagnetic compatability problem can be
reduced.
2) Common mode voltage(CM):
Multilevel converters produce small CM
voltage; therefore, the stress in the bearings
connected to a multilevel motor drive can be
reduced. Furthermore, CM voltage can be
eliminated by using advanced modulation
strategies such as that proposed in.
3) Input current: Multilevel converters can
draw input current with low distortion.
4)Switching frequency: Multilevel converters
can operate at both fundamental switching
frequency and high switching frequency PWM.
It should be noted that lower switching
frequency usually means lower switching loss
and higher efficiency.
Due to above feature we are using a multi level for
power control of induction motor.
1) One particular disadvantage is the greater
number of power semiconductor switches
needed.
2. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.
864 | P a g e
2) Although lower voltage rated switches can be
utilized in a multilevel converter, each switch
requires a related gate drive circuit.This may
cause the overall system to be more expensive
and complex.
INDEX
1) Introduction
2-3
2) Two types of multilevel inverter
5-6
3) Methodology
14-17
4) Note
18
5) Harmonic effects of induction motor
18-20
6) Conclusion
21
7) Acknowledgement
22
8) Literature survey
23
CONTENTS
LIST OF FIGURES:
1,2,3(a),3(b),3(c),3(d),4,5,6,7
2. - Two Types of Multilevel Inverter
1) Symmetrical type Multilevel Inverter
2) Asymmetrical type Multilevel Inverter
In symmetrical multilevel inverter, all H-
bridge cells are fed by equal voltages and
hence all the arm cells produce similar output
voltages.
If all the cells are not fed by equal voltages, the
inverter becomes an asymmetrical one. In this
inverter,the arm cells have different effect on
the output voltage.
The cascade H-Bridge inverter consists of
power conversion cells, each supplied by an
isolated dc source on the dc side,which can be
obtained from batteries, fuel cells, or ultra
capacitors and series connected on the a.c side.
Fig1 shows a one phase circuit for a machine
drive using 3cascade H-bridge inverter consist
of MOSFETS.
If we will provide voltage 1Vdc,1Vdc,1Vdc
with G.P ratio 1 to the three H-bridge then the
simulation output will be as shown in the
Fig2.It is called 7 level symmetrical output of
as we are providing symmetrical
voltages.V0,1(t)=1Vdc,V0,2(t)=1Vdc,V0,3(t)=
1Vdc shows the output waveform of the
individual bridge and V0(t)=3Vdc shows the
summation of above 3 waveforms.
If we will provide voltage 1Vdc,2Vdc,4Vdc,
with G.P ratio 2 to the three H-bridge then the
total simulation output V0(t)=15Vdc will be
as shown in Fig3(d).It is called 15 level
symmetrical output as we are providing
asymmetrical voltages.
.V0,1(t)=1Vdc,V0,2(t)=2Vdc,V0,3(t)=4Vdc
shows the output waveform of individual
bridge as shown in Fig3(a),Fig3(b),Fig3(c)
respectively.
An output phase voltage waveform is obtained
by summing the bridges output voltages.
V0(t)=V0,1(t) + V02(t) +……+V0,N(t) ;
(1)
Where N is the number of cascaded bridges.
Again ,if all dc voltage sources in Fig1 are
equal to Vdc, the inverter is then known as a
symmetric multilevel And if all dc voltage
sources are not equal it is called Asymmetrical
multilevel inverter.
3. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.863-872
865 | P a g e
4. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.
866 | P a g e
Fig2.
5. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.
867 | P a g e
Advantages Of Asymmetrical Type Multi Level Inverter:
6. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.
868 | P a g e
The main advantage of asymmetrical multilevel inverters is the optimization of levels with a minimum
number of power supplies.
The increase in the number of voltage levels reduces the total harmonic distortion (THD), the common-
mode voltages, the output filters, and the switching losses.
The main bridges, which carry 80% of the total power, work at a very low frequency.
In some particular operation it can be operated with a single dc source.
It enables the use of the Renewable Power Sources.
Disadvantages Of Asymmetrical Type Multi Level Inverter:
• They need many independent power supplies that must be floating, isolated, and balanced.
• In some particular levels of voltage, bidirectional power supplies are required, and the same happens
when regenerative braking needs to be applied.
• The direct relation between the number of levels and the voltage amplitude, which produce a loss of
quality when the output voltage is reduced.
Costly and complex topologies have to be implemented to get the isolated supplies.
Block Diagram:
Fig4: Main Components Of 27 Level Asymmetrical Type Multi Level Inverter For 1 Phase
7. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.
869 | P a g e
3.METHODOLOGY:
Refer to Fig4 the voltage supplied to the 3
H-Bridge will be scaled in power 3 according to
G.P ratio.The driver circuit will individually drive
the gates of the MOSFET’s connected in H-Bridge
or optocoupler can be used in place of driver
circuits.
All individual bridge is supplied by the d.c voltage
which is multiple of 3 as shown in Figure.
The controller IC which generate the clock pulse
will be programmed according to the phase delay
we want in the clock pulse cycle and the duration
we want of each clock pulse. Here the phase delay
are providing as 0.02*1/56 seconds. For one gate
pulse i.e. in a graph paper if we will draw the gate
waveform for each bridge then for 1cm block we
are providing as 0.02*1/56 seconds. The output we
will get is shown in Fig5. The 3 outputs
Vo1=1Vdc,V02=3Vdc,V03=9Vdc is showing the
output of each bridge of the circuit and their total
output after summation is 13Vdc waveform which
is shown in Fig5. The maximum output voltage we
will get is 13Vdc. It is called as 27 level output or
27 level symmetrical output.
Now if we will increase the level from 27
level to 81 level by increasing one more H-Bridge
in Fig4. I.e. having
V01=1Vdc,V02=3Vdc,V03=9Vdc and V04=27Vdc
having same G.P ratio. As shown in Fig6. And the
total output waveform is shown in Fig7.
8. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.
870 | P a g e
Fig7
9. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.863-872
871 | P a g e
From 81 level total output waveform we have seen
that almost same output we are getting here as it
was in 27 level case at the cost of limitations in 81
level circuitry. So it is not sensible to go upto
higher level. The limitations with 81 level circuitry
are as follows:
1) Switching frequency of the bridge which
shares the minimum power will increase.
2) At the cost of the fourth bridge reduction in
THD is not appreciable.
3) Master Bridge(higher rating voltage bridge)
will have to share the max. Power
4) Distribution of power will not be uniform.
5) Rating of the master bridge will be too high in
comparison with the rating of the bridge which
shares the minimum power.
4-NOTE-We are considering here G.P ratio as 3
instead of 2 because it Higher voltage output and
higher level output.
5.HARMONIC EFFECTS ON
INDUCTION MOTOR-
Induction motors are commonly used in
industry and sensitive to voltages harmonics and
their operation and efficiency can be affected
intensely their supplied power quality. Some
oscillations in three phase induction motors torque
appear on launch time which these oscillations
damped in very short time. Although the torque
amount can be negative in that time but average
value remain positive because of motors stable
operation. If we use from speed-torque curve for
depict of motor behavior in steady state. In every
applications these oscillations will not be
appreciable and can be negligible. In non sinusoidal
supply conditions the oscillations existing in
transient state is not damped and survive to steady
state (with small value) which mainly leads to
reduction of the efficiency of the motor. Various
industrial loads including static converters (such as
electric furnace, induction heating devices and
switching power supply) inject current harmonics
in power systems Generally power electronic
devices such as switching sources and converters
are most important sources of harmonic generation.
Converters usually generate harmonics from nth
level in AC side.
n = knp±1 (2)
Where:
k is a constant and np is the number of
converter pulses.
This phenomena lead to distortion in voltage
like as iron saturation in over loaded
distribution transformers. Induction motor
under perfect sinusoidal supply condition
generate little amount of current harmonics.
Because of its coils structure and non linear
behavior of iron core. Most important
consequent of this phenomena is efficiency
decrease of motor.
Installation of capacitor placement in
distribution systems for power factor correction
and series reactor in transmission lines for
decrease in short circuit current are not direct
causes of harmonic generating but because of
probability of resonance generation can intense
and magnify existed harmonics.
Voltage harmonic because of heat and
oscillations produce in rotor cause most
important damage to induction motor. Rotors
oscillations are because of torque ripples and
these ripples emerge from positive and negative
ordinary harmonics. Rotors oscillations can
increase friction losses of bearings. Since
motors temperature in present of any harmonic
would be higher than normal state and this will
damage to bearings and stator coil and
consequently motors life will be decreased. For
preventing of excessive rise of motors
temperature, motors should be derated. This
derating leads to increase of energy
consumption and cause more damages to
consumers.
6.CONCLUSION:-
The Assymetrical multilevel inverter
topology is used for the optimization of levels with
a mimimum no. of voltage sources. It is used where
medium voltage and higher power is required.A
multilevel inverter is more advantageous in
comparison with a conventional two-level
converter that uses high switching frequency pulse
width modulation(PWM).The increase in the
number of level in multilevel inverter reduces the
total harmonic distortion (THD),common mode
voltages,the output filters and the switching losses
and hence power flow can be controlled by
providing smooth a.c sine wave to the induction
motor to mainly prevent the reduction of the
efficiency of the motor due to harmonics which are
present in normal power supply.
ACKNOWLEDGEMENT
It gives me immense pleasure to express
my deepest sense of gratitude and sincere thanks to
my greatly respected guide Mrs.Paramjeet Kaur
Assistant Professor in the Department of Electrical
and Electronics Engineering,NIIST ,Bhopal,for
their valuable guidance encouragement and help for
this work.
I express my deep sense of gratitude to Dr. Amita
Mahor(Prof. & H.O.D), Electrical and Electronics
Engineering,NIIST ,Bhopal,for his keen
interest,continued encouragement and support.
10. Miss Vani Mishra, Mrs.Paramjeet Kaur / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.
872 | P a g e
I am also thankful to all the staff members of the
Department of Electrical and Electronics
Engineering,Bhopal, for their cooperation in my
work.
Literature survey:
[1]. Juan Dixon, Javier Pereda “Asymmetrical
Multilevel Inverter for Traction Drives
Using Only One DC Supply” IEEE
Transactions On Vehicular Technology,
Vol. 59, No. 8, October 2010
[2]. Farid Khoucha, Mouna Soumia Lagoun,
Abdelaziz Kheloui, and Mohamed El
Hachemi Benbouzid “A Comparison of
Symmetrical and Asymmetrical Three-
Phase H-Bridge Multilevel Inverter for
DTC Induction Motor Drives” IEEE
Transactions On Energy Conversion, Vol.
26, No. 1, March 2011
[3]. Bambang Sujanarko, Mochamad Ashari
“Advanced Carrier Based Pulse Width
Modulation in Asymmetric Cascaded
Multilevel Inverter” International Journal
of Electrical & Computer Sciences IJECS-
IJENS Vol: 10 No: 06.
[4]. Diorge Alex Báo Zambra, Cassiano Rech◊
and José Renes Pinheiro “COMPARISON
AMONG THREE TOPOLOGIES OF
MULTILEVEL INVERTERS”