This document summarizes research on using a cascaded five-level Z-Source inverter for fuel cell applications. The proposed topology employs a Z network between the DC source and inverter to achieve boost operation. Maximum boost control with third harmonic injection PWM is analyzed, which turns all traditional zero states into shoot-through states. Simulations in MATLAB/Simulink show that this control method provides high voltage gain, reduced total harmonic distortion, and reduced voltage stress compared to simple boost control. The maximum boost control is well-suited for the proposed cascaded Z-Source inverter topology.
This paper presents investigation and performance analysis of novel down sampling based clamping SV PWM technique for diode and cascaded Multi-level Invereter fed to Induction motor drive. A novel down sampling based clamping SVPWM has developed by adding triangular off set to sinusoidal fundamental waveform is modified by down sampling the reference wave by order of 10 so this technique is called clamping space vector pulse width modulation techniques such as PD, POD and APOD. so as to shift the lower order harmonics to higher order side. This novel carrier is compared with the offset injected space vector reference waveform to generate the required PWM pulses to the inverter. To analyze the performance of the proposed PWM technique it is implemented on seven level diode and cascaded Multi-level Inverter using Matlab/Simulink software tool for output line, phase voltage, currents, speed, torque and Total harmonic distortion analysis.
This document discusses Matlab/Simulink implementation for reducing motor derating and torque pulsation of an induction motor using a matrix converter. It provides background on how non-sinusoidal supply from traditional inverters causes harmonic losses and torque pulsation in induction motors. The document summarizes simulation results showing that a matrix converter can provide a pure sinusoidal supply, reducing harmonic losses and torque pulsation. Simulations of a matrix converter driving an induction motor in Matlab/Simulink are presented, showing sinusoidal voltage/current waveforms and reduced torque pulsation at steady state.
Multilevel inverters (MLI) are becoming more popular over the years for medium and high power applications because of its significant merits over two level inverters. This paper presents an implementation of multicarrier based sinusoidal pulse width modulation technique for three phase seven level diode clamped multilevel inverter. This topology is operated under phase opposition disposition pulse width modulation technique. The performance of three phase seven level diode clamped inverter is analyzed for induction motor (IM) load. Simulation is performed using MATLAB/SIMULINK. Experimental results are presented to validate the effectiveness of the operation of the diode clamped multilevel inverter using field programmable gate array.
This paper addresses a novel approach for designing and modeling of the isolated
flyback converter. Modeling is done without parasitic as well as with parasitic components.
A detailed analysis, simulation and different control strategy are conferred for flyback
converter in continuous conduction mode (CCM). To verify the design and modeling at
primary stage, study of the converter is practiced in CCM operation for input AC voltage
230V at 50Hz and output DC voltage of 5V and 50W output power rating using PSIM 6.0
software. Simulation result shows a little ripple in output of the converter in open loop. Finally
in order to evaluate the system as well as response of the controller, flyback converter is
simulated using MATLAB. This work, highlighting the modeling when the system have
transformer and facilitate designers to go for it when they need one or more than one output
for a given application upto 150W
Fuzzy Logic Controlled Harmonic Suppressor in Cascaded Multilevel InverterIJPEDS-IAES
This paper presents an investigation of seven level cascaded H-bridge (CHB)
inverter in power system for compensation of harmonics. For power quality
control a Fuzzy Logic Control (FLC) giving comparatively better harmonic
reduction than the conventional controllers. Harmonic distortion is the most
important power quality problem stirring in multilevel inverter; the
harmonics can be eliminated by an optimal selection of switching angles. A
hybrid evaluation technique evaluates the obtained optimal switching angles
that are attained from the fuzzy inference system as well as neural network.
The proposed method will be implemented in MATLAB working platform
and the harmonic elimination performance will be evaluated.
This document analyzes a transistor clamped H-bridge split phase PWM inverter. It presents the circuit diagram of the proposed inverter which uses coupled inductors to prevent short circuits and reduce reverse recovery losses. A double reference single carrier modulation technique is used to generate PWM signals from two reference signals and a triangular carrier, producing a five-level output voltage. Simulation results in MATLAB Simulink show the five-level output voltage waveform and total harmonic distortion of 8.43%, demonstrating reduced harmonics compared to conventional inverters. The proposed inverter topology and modulation control method aim to improve efficiency, reliability and output waveform quality.
This document analyzes the total harmonic distortion (THD) of 7, 9, and 11 level cascaded H-bridge multilevel inverters using multicarrier pulse width modulation. The analysis found that THD in the output voltage decreases and output voltage increases with more levels. Simulations in MATLAB/Simulink showed that an 11-level inverter had the lowest THD at 11.1%, while a 7-level inverter had the highest THD at 24.64%. More levels therefore better reduced the harmonic distortion.
This paper presents investigation and performance analysis of novel down sampling based clamping SV PWM technique for diode and cascaded Multi-level Invereter fed to Induction motor drive. A novel down sampling based clamping SVPWM has developed by adding triangular off set to sinusoidal fundamental waveform is modified by down sampling the reference wave by order of 10 so this technique is called clamping space vector pulse width modulation techniques such as PD, POD and APOD. so as to shift the lower order harmonics to higher order side. This novel carrier is compared with the offset injected space vector reference waveform to generate the required PWM pulses to the inverter. To analyze the performance of the proposed PWM technique it is implemented on seven level diode and cascaded Multi-level Inverter using Matlab/Simulink software tool for output line, phase voltage, currents, speed, torque and Total harmonic distortion analysis.
This document discusses Matlab/Simulink implementation for reducing motor derating and torque pulsation of an induction motor using a matrix converter. It provides background on how non-sinusoidal supply from traditional inverters causes harmonic losses and torque pulsation in induction motors. The document summarizes simulation results showing that a matrix converter can provide a pure sinusoidal supply, reducing harmonic losses and torque pulsation. Simulations of a matrix converter driving an induction motor in Matlab/Simulink are presented, showing sinusoidal voltage/current waveforms and reduced torque pulsation at steady state.
Multilevel inverters (MLI) are becoming more popular over the years for medium and high power applications because of its significant merits over two level inverters. This paper presents an implementation of multicarrier based sinusoidal pulse width modulation technique for three phase seven level diode clamped multilevel inverter. This topology is operated under phase opposition disposition pulse width modulation technique. The performance of three phase seven level diode clamped inverter is analyzed for induction motor (IM) load. Simulation is performed using MATLAB/SIMULINK. Experimental results are presented to validate the effectiveness of the operation of the diode clamped multilevel inverter using field programmable gate array.
This paper addresses a novel approach for designing and modeling of the isolated
flyback converter. Modeling is done without parasitic as well as with parasitic components.
A detailed analysis, simulation and different control strategy are conferred for flyback
converter in continuous conduction mode (CCM). To verify the design and modeling at
primary stage, study of the converter is practiced in CCM operation for input AC voltage
230V at 50Hz and output DC voltage of 5V and 50W output power rating using PSIM 6.0
software. Simulation result shows a little ripple in output of the converter in open loop. Finally
in order to evaluate the system as well as response of the controller, flyback converter is
simulated using MATLAB. This work, highlighting the modeling when the system have
transformer and facilitate designers to go for it when they need one or more than one output
for a given application upto 150W
Fuzzy Logic Controlled Harmonic Suppressor in Cascaded Multilevel InverterIJPEDS-IAES
This paper presents an investigation of seven level cascaded H-bridge (CHB)
inverter in power system for compensation of harmonics. For power quality
control a Fuzzy Logic Control (FLC) giving comparatively better harmonic
reduction than the conventional controllers. Harmonic distortion is the most
important power quality problem stirring in multilevel inverter; the
harmonics can be eliminated by an optimal selection of switching angles. A
hybrid evaluation technique evaluates the obtained optimal switching angles
that are attained from the fuzzy inference system as well as neural network.
The proposed method will be implemented in MATLAB working platform
and the harmonic elimination performance will be evaluated.
This document analyzes a transistor clamped H-bridge split phase PWM inverter. It presents the circuit diagram of the proposed inverter which uses coupled inductors to prevent short circuits and reduce reverse recovery losses. A double reference single carrier modulation technique is used to generate PWM signals from two reference signals and a triangular carrier, producing a five-level output voltage. Simulation results in MATLAB Simulink show the five-level output voltage waveform and total harmonic distortion of 8.43%, demonstrating reduced harmonics compared to conventional inverters. The proposed inverter topology and modulation control method aim to improve efficiency, reliability and output waveform quality.
This document analyzes the total harmonic distortion (THD) of 7, 9, and 11 level cascaded H-bridge multilevel inverters using multicarrier pulse width modulation. The analysis found that THD in the output voltage decreases and output voltage increases with more levels. Simulations in MATLAB/Simulink showed that an 11-level inverter had the lowest THD at 11.1%, while a 7-level inverter had the highest THD at 24.64%. More levels therefore better reduced the harmonic distortion.
IRJET- Design and Implementation of Isolated Multi-Output Flyback ConverterIRJET Journal
This document describes the design and implementation of an isolated multi-output flyback converter. A flyback converter uses a single switch and transformer to provide isolated output voltages from an input source. The designed converter uses a toroidal transformer with multiple secondary windings to generate multiple isolated output voltages at fixed levels. Simulation results and specifications for the transformer, switch, and outputs are provided. The flyback converter provides an efficient and low-cost solution for applications requiring multiple isolated low-power DC outputs.
This document describes a simulation of a space vector PWM controller for a five-level voltage-fed inverter motor drive. It begins by introducing multilevel inverters and some of the challenges in controlling them, specifically the increased complexity with more levels. It then presents a new approach to implementing space vector PWM for a five-level inverter by treating it as a conventional two-level system, making the calculations simpler. The methodology and implementation are described, including estimating switching times. Simulation results are presented showing the current, voltage and THD waveforms both with and without an LC filter. It is concluded that the proposed 2D system approach allows for simple implementation of SVPWM for a five-level inverter using common D
This document describes a three level neutral point clamped (NPC) inverter. It includes:
1. A diagram of the 3-level NPC inverter circuit and descriptions of the switching states.
2. Calculations of the switching vectors for each switching state by analyzing equivalent circuits.
3. Tables listing the 27 possible switching states and their corresponding switching vectors.
Design and Simulation of Low Pass Filter for Single phase full bridge Inverte...IJERA Editor
Sinusoidal pulse width modulation SPWM technique is widely preferred to other modulation techniques as the
Inverter output frequency obtained is equal to the required fundamental frequency. SPWM with unipolar voltage
switching is used as it results in cancellation of harmonic component at the switching frequencyin the output
voltage, also the sidebands of the switching frequency harmonics disappear and in addition to this, other
dominant harmonic at twice the switching frequency gets eliminated. Hence, due to these advantages unipolar
voltage switching with SPWMis used for Inverter switching. In this paper, an in-depth analysis of unipolar
voltage switching technique with SPWM as applied to a single-phase full bridge Inverter is described and
designing of an efficient, active low pass filter LPF is discussed for an particular cut-off frequency,푓푐 and
damping factor zeta, 휁 and the filter is placed at the output side of a single-phase full bridge Inverter and
therefore eliminating the harmonic component from the Inverter output voltage resulting in a pure sinusoidal ac
voltage waveform.
The document analyzes the conduction modes and efficiency of buck-boost, buck, and boost power converters. Simulation results show that continuous conduction mode (CCM) has the highest efficiency for all three converters. For a given duty cycle, increasing the inductor value decreases the peak-to-peak ripple. The conduction mode can also be varied by keeping the inductance constant and changing the duty cycle, which keeps the ripple value the same. Therefore, the filter is designed for a specific inductance value. Tables of results are presented comparing efficiency for different conduction modes under varying duty cycles and inductance values.
Analysis Approach for Five Phase Two-Level Voltage Source Inverter with PWM T...ijsrd.com
this paper gives idea of comparison of five phase two-level voltage inverter (FPTLVSI) without filter circuit and control scheme and FPTLVSI with filter circuit and PWM control scheme for induction motor drive. The paper demonstrates using mat lab simulations about comparison in term of harmonics analysis for different firing angles and find best angle suitable for output with minimum harmonics for FPTLVSI without filter circuit and control scheme and harmonics analysis of FPTLVSI with filter and PWM control scheme. This paper suggests simulation of comparison of harmonics point of view five phase two-level voltage inverter (FPTLVSI) without filter circuit and control scheme and with filter circuit and PWM control scheme for induction motor drive.
Soft Switched Resonant Converters with Unsymmetrical ControlIOSR Journals
1) The document describes a half-bridge DC-DC converter with unsymmetrical control that achieves zero-voltage switching (ZVS). By operating one switch with less than 50% duty cycle and the other with greater than 50% duty cycle, soft switching conditions can be achieved using the passive elements.
2) A prototype 5V, 50W half-bridge converter was designed, fabricated, and tested to validate the performance of the converter. Experimental waveforms confirmed ZVS turn-on of the power devices.
3) The converter topology exhibits benefits of both resonant converters like zero switching losses and switched-mode circuits like low conduction losses, due to the unsymmetrical duty ratio control at a constant switching frequency.
Isae 2011 A HYBRID CONTROLLER DESIGN FOR KEEPING CONSTANT VOLTAGE AND CURREN...Pandu Sandi Pratama
This document summarizes a presentation on modeling and control of a gas metal arc welding (GMAW) system. [1] A proportional controller is proposed to maintain constant output welding voltage for the GMAW power supply. [2] A fuzzy-sliding mode controller is proposed for the wire feeding unit to keep the output welding current constant by adjusting the electrode feed rate. [3] Simulation results show the hybrid controller using these two controllers achieves better performance than a conventional PID controller in terms of rise time, settling time, and steady state error of the output current.
APPLICATIONS OF FLOATING-GATE MOSFET IN THE DESIGN OF INVERTER AND RING OSCIL...elelijjournal
This paper presents the application of floating-gate MOSFET (FGMOS) in the design of low voltage and
high speed digital circuits wherein threshold voltage tunability of FGMOS has been exploited to enhance
the performance of inverter in terms of various parameters like switching threshold voltage, noise margins,
propagation delay and energy delay product. It has been observed that by varying the bias voltage in
FGMOS, the voltage transfer characteristics can be altered that result in lowering of switching threshold
voltage, increased noise margins, reduced propagation delay and less energy delay product as compared to
the standard CMOS inverter. This paper also demonstrates the design of ring oscillator using FGMOS and
it has been found that FGMOS based ring oscillator exhibits higher frequency of oscillation as compared to
its CMOS counterpart. The performance of these circuits has been verified through PSpice simulations
carried out using level 7 parameters in 0.13 µm CMOS technology with a supply voltage of 1 V.
SINGLE PHASE SYMMETRICAL MULTILEVEL INVERTER DESIGN FOR VARIOUS LOADSelelijjournal
This paper presents a single phase symmetrical multilevel inverter with various loads. This proposed
topology is connected with R-load, RL-load and induction motor drive with unipolar Phase disposition
PWM technique. Among the four modulation technique it gives reduced harmonic. This proposed topology
has less number of switches than the conventional one. In conventional cascaded multilevel inverter have
twelve switches and the proposed topology have eight switches. Totally the four switches have been
reduced from the conventional one. It is designed to produce a seven level output. The simulation analysis
has been done by a MATLAB/SIMULINK model.
Multi Carrier based Multilevel Inverter with Minimal Harmonic DistortionIJPEDS-IAES
This paper presents performance features of Asymmetric Cascaded
Multilevel inverter. Multilevel inverters are commonly modulated by using
multicarrier pulse width modulation (MCPWM) techniques such as phaseshifted
multicarrier modulation and level-shifted multicarrier modulation.
Amongst these, level-shifted multicarrier modulation technique produces the
best harmonic performance. This work studies about multilevel inverter with
unequal DC sources using level shifting MCPWM technique. The
Performances indices like Total Harmonic Distortion (THD), number of
switches and DC Sources are considered. A procedure to achieve an
appropriate level shifting is also presented is this paper.
This document describes the design and simulation of a five-level cascaded inverter using multilevel sinusoidal pulse width modulation strategies. It presents the circuit design of a single-phase five-level cascaded inverter and discusses four types of multilevel sinusoidal PWM techniques - alternative phase opposition disposition, phase disposition, phase-shifted, and phase opposition disposition. The total harmonic distortion for each technique is analyzed through MATLAB/Simulink simulations. The results show that phase opposition disposition PWM has the lowest harmonic content compared to the other techniques.
Soft Switched Multi-Output Flyback Converter with Voltage DoublerIJPEDS-IAES
A novel multi-output voltage doubler circuit with resonant switching
technique is proposed in this paper. The resonant topology in the primary
side of the flyback transformer switches the device either at zero voltage or
current thus optimizing the switching devices by mitigating the losses. The
voltage doubler circuit introduced in the load side increases the voltage by
twice the value thereby increasing the load power and density. The proposed
Multi-output Isolated Converter removes the need for mutiple SMPS units
for a particular application. This reduces the size and weight of the
converters considerably leading to a greater payload. This paper aims at
optimizing the proposed converter with some design changes. The results
obtained from the hardware prototype are given in a comprehensive manner
for a 3.5W converter operating at output voltages of 5V and 3.3V at 50 kHz
switching frequency. The converter output is regulated with the PI controller
designed with SG3523 IC. The effects of load and line regulation for ±20%
variations are analyzed in detail.
The document discusses regulated DC power supplies and their components. It explains that a regulated DC power supply consists of a step-down transformer, rectifier, filter, and voltage regulator. The transformer steps down AC voltage, the rectifier converts it to DC, the filter smooths the output, and the regulator sets the output to a fixed voltage. It then discusses half-wave and full-wave rectifiers in detail, deriving their key parameters such as DC output voltage and current, ripple factor, and efficiency.
The document summarizes the key components and operation of a regulated DC power supply. It consists of a step-down transformer, rectifier, filter, and voltage regulator. The transformer steps down AC voltage, the rectifier converts it to DC but with variation, the filter smooths the output, and the regulator sets the output to a fixed voltage. Rectifiers are then discussed in more detail, including half-wave and full-wave rectifiers. Key rectifier parameters like DC output voltage and current, ripple factor, and efficiency are defined. Half-wave rectifier operation and analysis is explained through derivations of these parameters.
Equal Switching Distribution Method for Multi-Level Cascaded Inverterijsrd.com
the paper proposes a new method of equal switching distribution that can be applied to cascaded multilevel inverters. This method is based on the fact that in the cascaded multilevel inverters, the output phase voltage is the sum of voltage waveforms produced by all cascaded cells. By periodically exchanging cells' voltage waveforms, the proposed method ensures equal average switching's distribution between all cascaded cells. This method is applied to the 13-level inverter, which consists of three cascaded 5-level H-bridge cells per phase. However, the proposed method can be extended to any desired number of voltage levels and applied to any type of cascaded multilevel inverter. Extensive simulation results of the tested 13- level inverter with the equal switching distribution are presented. Moreover, the proposed method is compared to the standard control approaches and its advantages are shown.
The power electronics device which converts DC power to AC power at required output voltage and frequency level is known as inverter. Multilevel inverter is to synthesize a near sinusoidal voltage from several levels of dc voltages. In order to maintain the different voltage levels at appropriate intervals, the conduction time intervals of MOSFETS have been maintained by controlling the pulse width of gating pulses. In this paper single phase to three phase power conversion using PWM technique. The simulation is carried out in MATLAB/Simulink environment which demonstrate the feasibility of proposed scheme.
This document describes a class-G headphone amplifier designed in 65nm CMOS technology. The class-G amplifier uses two voltage supply rails and switches between them based on the output voltage level to improve efficiency. A novel switching technique called "switching currents injection" is used to enable a smooth transition between the supply rails with low distortion. The integrated circuit operates from 1.4V and 0.35V supplies. It achieves over 80dB THD+N for outputs over 16mW into 32 ohms headphones while consuming only 0.41mW of quiescent power. The active die area is 0.14mm2.
Third Harmonic Injection Control Method for L-Z-Source Inverter Fed Motor DriveIJERD Editor
This document discusses a proposed inductor type Z-source inverter with third harmonic injection control method. The proposed inverter eliminates capacitors from the traditional Z-source inverter circuit to avoid large inrush currents. It contains two inductors and three diodes instead. Third harmonic injection control is also proposed to further reduce total harmonic distortion and losses compared to traditional Z-source inverters. Simulation results show the proposed inverter produces three-phase output voltages of 700V and currents of 10A from an input of 230V DC. Harmonic analysis confirms the third harmonic injection control reduces harmonic levels as the number of cycles increases.
Proposed Method for Shoot-Through in Three Phase ZSI and Comparison of Differ...IAES-IJPEDS
This paper presented the new methodology for different control techniques applied to three phase Z-source inverter for minimisation of switching losses. The procedure for proposed control techniques and its effects on the performance of operation of three phase Z-source inverter are analyzed. The graphs for voltage gain and voltage stress are drawn for different control methods. The flow-chart for the symmetrical and unsymmetrical control techniques for creating pulse signals for switches of three phase inverter are shown. All the methods are studied and compared with each other. The Total harmonic distortion (THD) of output voltage of both the control methods has been analyzed using FFT analysis. The experiments done and the results shown for capacitor voltage, load current and load line voltage for simple boost and constant boost control techniques are presented using MATLAB/ Simulink.
This paper proposed a new sparce matrix converter with Z-source network to provide unity voltage transfer ratio. It is an ac-to-ac converter with diode-IGBT bidirectional switches. The limitations of existing matrix converter like higher current THD and less voltage transfer ratio issues are overcome by this proposed matrix converter by inserting a Z-source. Due to this Z-source current harmonics are totally removed. The simulation is performed for different frequencies. The simulation results are presented to verify the THD and voltage transfer ratio and compared with the existing virtual AC/DC/AC matrix converter. The experimental output voltage amplitude can be varied with the variable frequencies.
A 5-Level Single Phase Flying Capacitor Multilevel InverterIRJET Journal
This document presents a simulation and analysis of a single phase five level flying capacitor multilevel inverter. It explains the operating principle, topology, and components of the flying capacitor multilevel inverter. Simulations were conducted using Matlab/Simulink with both ideal switches and IGBT switches. The results show output voltage waveforms with five distinct levels that approximate a sinusoidal waveform. Triggering circuits using OR gates were also simulated to generate gate signals for the switches to produce the multilevel output.
IRJET- Design and Implementation of Isolated Multi-Output Flyback ConverterIRJET Journal
This document describes the design and implementation of an isolated multi-output flyback converter. A flyback converter uses a single switch and transformer to provide isolated output voltages from an input source. The designed converter uses a toroidal transformer with multiple secondary windings to generate multiple isolated output voltages at fixed levels. Simulation results and specifications for the transformer, switch, and outputs are provided. The flyback converter provides an efficient and low-cost solution for applications requiring multiple isolated low-power DC outputs.
This document describes a simulation of a space vector PWM controller for a five-level voltage-fed inverter motor drive. It begins by introducing multilevel inverters and some of the challenges in controlling them, specifically the increased complexity with more levels. It then presents a new approach to implementing space vector PWM for a five-level inverter by treating it as a conventional two-level system, making the calculations simpler. The methodology and implementation are described, including estimating switching times. Simulation results are presented showing the current, voltage and THD waveforms both with and without an LC filter. It is concluded that the proposed 2D system approach allows for simple implementation of SVPWM for a five-level inverter using common D
This document describes a three level neutral point clamped (NPC) inverter. It includes:
1. A diagram of the 3-level NPC inverter circuit and descriptions of the switching states.
2. Calculations of the switching vectors for each switching state by analyzing equivalent circuits.
3. Tables listing the 27 possible switching states and their corresponding switching vectors.
Design and Simulation of Low Pass Filter for Single phase full bridge Inverte...IJERA Editor
Sinusoidal pulse width modulation SPWM technique is widely preferred to other modulation techniques as the
Inverter output frequency obtained is equal to the required fundamental frequency. SPWM with unipolar voltage
switching is used as it results in cancellation of harmonic component at the switching frequencyin the output
voltage, also the sidebands of the switching frequency harmonics disappear and in addition to this, other
dominant harmonic at twice the switching frequency gets eliminated. Hence, due to these advantages unipolar
voltage switching with SPWMis used for Inverter switching. In this paper, an in-depth analysis of unipolar
voltage switching technique with SPWM as applied to a single-phase full bridge Inverter is described and
designing of an efficient, active low pass filter LPF is discussed for an particular cut-off frequency,푓푐 and
damping factor zeta, 휁 and the filter is placed at the output side of a single-phase full bridge Inverter and
therefore eliminating the harmonic component from the Inverter output voltage resulting in a pure sinusoidal ac
voltage waveform.
The document analyzes the conduction modes and efficiency of buck-boost, buck, and boost power converters. Simulation results show that continuous conduction mode (CCM) has the highest efficiency for all three converters. For a given duty cycle, increasing the inductor value decreases the peak-to-peak ripple. The conduction mode can also be varied by keeping the inductance constant and changing the duty cycle, which keeps the ripple value the same. Therefore, the filter is designed for a specific inductance value. Tables of results are presented comparing efficiency for different conduction modes under varying duty cycles and inductance values.
Analysis Approach for Five Phase Two-Level Voltage Source Inverter with PWM T...ijsrd.com
this paper gives idea of comparison of five phase two-level voltage inverter (FPTLVSI) without filter circuit and control scheme and FPTLVSI with filter circuit and PWM control scheme for induction motor drive. The paper demonstrates using mat lab simulations about comparison in term of harmonics analysis for different firing angles and find best angle suitable for output with minimum harmonics for FPTLVSI without filter circuit and control scheme and harmonics analysis of FPTLVSI with filter and PWM control scheme. This paper suggests simulation of comparison of harmonics point of view five phase two-level voltage inverter (FPTLVSI) without filter circuit and control scheme and with filter circuit and PWM control scheme for induction motor drive.
Soft Switched Resonant Converters with Unsymmetrical ControlIOSR Journals
1) The document describes a half-bridge DC-DC converter with unsymmetrical control that achieves zero-voltage switching (ZVS). By operating one switch with less than 50% duty cycle and the other with greater than 50% duty cycle, soft switching conditions can be achieved using the passive elements.
2) A prototype 5V, 50W half-bridge converter was designed, fabricated, and tested to validate the performance of the converter. Experimental waveforms confirmed ZVS turn-on of the power devices.
3) The converter topology exhibits benefits of both resonant converters like zero switching losses and switched-mode circuits like low conduction losses, due to the unsymmetrical duty ratio control at a constant switching frequency.
Isae 2011 A HYBRID CONTROLLER DESIGN FOR KEEPING CONSTANT VOLTAGE AND CURREN...Pandu Sandi Pratama
This document summarizes a presentation on modeling and control of a gas metal arc welding (GMAW) system. [1] A proportional controller is proposed to maintain constant output welding voltage for the GMAW power supply. [2] A fuzzy-sliding mode controller is proposed for the wire feeding unit to keep the output welding current constant by adjusting the electrode feed rate. [3] Simulation results show the hybrid controller using these two controllers achieves better performance than a conventional PID controller in terms of rise time, settling time, and steady state error of the output current.
APPLICATIONS OF FLOATING-GATE MOSFET IN THE DESIGN OF INVERTER AND RING OSCIL...elelijjournal
This paper presents the application of floating-gate MOSFET (FGMOS) in the design of low voltage and
high speed digital circuits wherein threshold voltage tunability of FGMOS has been exploited to enhance
the performance of inverter in terms of various parameters like switching threshold voltage, noise margins,
propagation delay and energy delay product. It has been observed that by varying the bias voltage in
FGMOS, the voltage transfer characteristics can be altered that result in lowering of switching threshold
voltage, increased noise margins, reduced propagation delay and less energy delay product as compared to
the standard CMOS inverter. This paper also demonstrates the design of ring oscillator using FGMOS and
it has been found that FGMOS based ring oscillator exhibits higher frequency of oscillation as compared to
its CMOS counterpart. The performance of these circuits has been verified through PSpice simulations
carried out using level 7 parameters in 0.13 µm CMOS technology with a supply voltage of 1 V.
SINGLE PHASE SYMMETRICAL MULTILEVEL INVERTER DESIGN FOR VARIOUS LOADSelelijjournal
This paper presents a single phase symmetrical multilevel inverter with various loads. This proposed
topology is connected with R-load, RL-load and induction motor drive with unipolar Phase disposition
PWM technique. Among the four modulation technique it gives reduced harmonic. This proposed topology
has less number of switches than the conventional one. In conventional cascaded multilevel inverter have
twelve switches and the proposed topology have eight switches. Totally the four switches have been
reduced from the conventional one. It is designed to produce a seven level output. The simulation analysis
has been done by a MATLAB/SIMULINK model.
Multi Carrier based Multilevel Inverter with Minimal Harmonic DistortionIJPEDS-IAES
This paper presents performance features of Asymmetric Cascaded
Multilevel inverter. Multilevel inverters are commonly modulated by using
multicarrier pulse width modulation (MCPWM) techniques such as phaseshifted
multicarrier modulation and level-shifted multicarrier modulation.
Amongst these, level-shifted multicarrier modulation technique produces the
best harmonic performance. This work studies about multilevel inverter with
unequal DC sources using level shifting MCPWM technique. The
Performances indices like Total Harmonic Distortion (THD), number of
switches and DC Sources are considered. A procedure to achieve an
appropriate level shifting is also presented is this paper.
This document describes the design and simulation of a five-level cascaded inverter using multilevel sinusoidal pulse width modulation strategies. It presents the circuit design of a single-phase five-level cascaded inverter and discusses four types of multilevel sinusoidal PWM techniques - alternative phase opposition disposition, phase disposition, phase-shifted, and phase opposition disposition. The total harmonic distortion for each technique is analyzed through MATLAB/Simulink simulations. The results show that phase opposition disposition PWM has the lowest harmonic content compared to the other techniques.
Soft Switched Multi-Output Flyback Converter with Voltage DoublerIJPEDS-IAES
A novel multi-output voltage doubler circuit with resonant switching
technique is proposed in this paper. The resonant topology in the primary
side of the flyback transformer switches the device either at zero voltage or
current thus optimizing the switching devices by mitigating the losses. The
voltage doubler circuit introduced in the load side increases the voltage by
twice the value thereby increasing the load power and density. The proposed
Multi-output Isolated Converter removes the need for mutiple SMPS units
for a particular application. This reduces the size and weight of the
converters considerably leading to a greater payload. This paper aims at
optimizing the proposed converter with some design changes. The results
obtained from the hardware prototype are given in a comprehensive manner
for a 3.5W converter operating at output voltages of 5V and 3.3V at 50 kHz
switching frequency. The converter output is regulated with the PI controller
designed with SG3523 IC. The effects of load and line regulation for ±20%
variations are analyzed in detail.
The document discusses regulated DC power supplies and their components. It explains that a regulated DC power supply consists of a step-down transformer, rectifier, filter, and voltage regulator. The transformer steps down AC voltage, the rectifier converts it to DC, the filter smooths the output, and the regulator sets the output to a fixed voltage. It then discusses half-wave and full-wave rectifiers in detail, deriving their key parameters such as DC output voltage and current, ripple factor, and efficiency.
The document summarizes the key components and operation of a regulated DC power supply. It consists of a step-down transformer, rectifier, filter, and voltage regulator. The transformer steps down AC voltage, the rectifier converts it to DC but with variation, the filter smooths the output, and the regulator sets the output to a fixed voltage. Rectifiers are then discussed in more detail, including half-wave and full-wave rectifiers. Key rectifier parameters like DC output voltage and current, ripple factor, and efficiency are defined. Half-wave rectifier operation and analysis is explained through derivations of these parameters.
Equal Switching Distribution Method for Multi-Level Cascaded Inverterijsrd.com
the paper proposes a new method of equal switching distribution that can be applied to cascaded multilevel inverters. This method is based on the fact that in the cascaded multilevel inverters, the output phase voltage is the sum of voltage waveforms produced by all cascaded cells. By periodically exchanging cells' voltage waveforms, the proposed method ensures equal average switching's distribution between all cascaded cells. This method is applied to the 13-level inverter, which consists of three cascaded 5-level H-bridge cells per phase. However, the proposed method can be extended to any desired number of voltage levels and applied to any type of cascaded multilevel inverter. Extensive simulation results of the tested 13- level inverter with the equal switching distribution are presented. Moreover, the proposed method is compared to the standard control approaches and its advantages are shown.
The power electronics device which converts DC power to AC power at required output voltage and frequency level is known as inverter. Multilevel inverter is to synthesize a near sinusoidal voltage from several levels of dc voltages. In order to maintain the different voltage levels at appropriate intervals, the conduction time intervals of MOSFETS have been maintained by controlling the pulse width of gating pulses. In this paper single phase to three phase power conversion using PWM technique. The simulation is carried out in MATLAB/Simulink environment which demonstrate the feasibility of proposed scheme.
This document describes a class-G headphone amplifier designed in 65nm CMOS technology. The class-G amplifier uses two voltage supply rails and switches between them based on the output voltage level to improve efficiency. A novel switching technique called "switching currents injection" is used to enable a smooth transition between the supply rails with low distortion. The integrated circuit operates from 1.4V and 0.35V supplies. It achieves over 80dB THD+N for outputs over 16mW into 32 ohms headphones while consuming only 0.41mW of quiescent power. The active die area is 0.14mm2.
Third Harmonic Injection Control Method for L-Z-Source Inverter Fed Motor DriveIJERD Editor
This document discusses a proposed inductor type Z-source inverter with third harmonic injection control method. The proposed inverter eliminates capacitors from the traditional Z-source inverter circuit to avoid large inrush currents. It contains two inductors and three diodes instead. Third harmonic injection control is also proposed to further reduce total harmonic distortion and losses compared to traditional Z-source inverters. Simulation results show the proposed inverter produces three-phase output voltages of 700V and currents of 10A from an input of 230V DC. Harmonic analysis confirms the third harmonic injection control reduces harmonic levels as the number of cycles increases.
Proposed Method for Shoot-Through in Three Phase ZSI and Comparison of Differ...IAES-IJPEDS
This paper presented the new methodology for different control techniques applied to three phase Z-source inverter for minimisation of switching losses. The procedure for proposed control techniques and its effects on the performance of operation of three phase Z-source inverter are analyzed. The graphs for voltage gain and voltage stress are drawn for different control methods. The flow-chart for the symmetrical and unsymmetrical control techniques for creating pulse signals for switches of three phase inverter are shown. All the methods are studied and compared with each other. The Total harmonic distortion (THD) of output voltage of both the control methods has been analyzed using FFT analysis. The experiments done and the results shown for capacitor voltage, load current and load line voltage for simple boost and constant boost control techniques are presented using MATLAB/ Simulink.
This paper proposed a new sparce matrix converter with Z-source network to provide unity voltage transfer ratio. It is an ac-to-ac converter with diode-IGBT bidirectional switches. The limitations of existing matrix converter like higher current THD and less voltage transfer ratio issues are overcome by this proposed matrix converter by inserting a Z-source. Due to this Z-source current harmonics are totally removed. The simulation is performed for different frequencies. The simulation results are presented to verify the THD and voltage transfer ratio and compared with the existing virtual AC/DC/AC matrix converter. The experimental output voltage amplitude can be varied with the variable frequencies.
A 5-Level Single Phase Flying Capacitor Multilevel InverterIRJET Journal
This document presents a simulation and analysis of a single phase five level flying capacitor multilevel inverter. It explains the operating principle, topology, and components of the flying capacitor multilevel inverter. Simulations were conducted using Matlab/Simulink with both ideal switches and IGBT switches. The results show output voltage waveforms with five distinct levels that approximate a sinusoidal waveform. Triggering circuits using OR gates were also simulated to generate gate signals for the switches to produce the multilevel output.
Analysis of the Performance of the Drive of the Z source Induction Motor Powe...IJSRED
This document analyzes the performance of a Z-source induction motor powered by a converter. It first provides background on Z-source inverters and their advantages over traditional inverters, including their ability to boost voltage. It then describes the functional principles of a Z-source inverter, including its active states, non-shoot-through zero state, and shoot-through zero state. The document aims to determine parameters of the Z-source inverter like boost factor, output voltages, and voltage gain for maximum constant boost control through simulation and experiments.
Analysis of Multilevel Inverter using Bipolar and Unipolar Switching Schemes ...ijsrd.com
Cascaded H-bridge Multilevel Inverter (MLI) is most efficient topology for medium and high voltage DC-AC conversion, having less output harmonics and less commutation losses. Disadvantages are their complexity, more number of power devices, passive components and a complex control circuitry. Here a Cascaded Hybrid Multilevel Inverter is used to produce a three phase 9-level output voltages. Now a day inverter is also know as a DC-AC converter, is one of the most popular part of electrical device. This proposed inverter widely used in industries application such as speed control of induction motor. This thesis focus on three phase 9-level bipolar and unipolar switching inverter with characteristics like output voltage boosting ability and also we discus about the bipolar and unipolar switching scheme along with capacitor voltage control. The modified topology uses Cascaded H-bridge (CHB) with bidirectional and unidirectional switches producing boost up output voltage. Here a hybrid Pulse Width Modulation (PWM) technique is applied to control the power devices. This modulation technique uses a sine wave and a repeating wave, these waves are combined and a complete reference wave is generated. There is comparative study between CHB and modified topology between number of power devices used and Total Harmonic Distortions (THD). THD of modified topology is reduced and analyzed by FFT window. The results are observed by MATLAB/SIMULINK software.
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Simulation and analysis of multilevel inverter with reduced number of switchesIAEME Publication
This document summarizes a research paper that proposes a new multilevel inverter topology with reduced number of switches compared to conventional cascaded H-bridge multilevel inverters. The proposed topology is a five-level inverter that requires only six switches compared to eight switches in a conventional design. Simulation results show the performance of the new topology is validated using MATLAB/Simulink software. The paper also describes the operating modes and switching techniques used in the new multilevel inverter design, including phase disposition, alternative phase opposition disposition, and phase opposition disposition pulse width modulation strategies.
Space Vector of Three Phase Three level Neutral Point Clamped Quasi Z Source ...IJTET Journal
Space vector of three phase three level neutral point clamped quasi z source inverter is proposed in this paper. Space vector modulation is the pulse width modulation consists of number of switching states. Space vector pulse width modulation technique utilizes 15% more power from DC source. Harmonics are reduced by the presence of switching states. Quasi Z-source inverter is advanced topologies which performs both boost and buck operation of a converter. The proposed inverter obtains continuous input current and the boost converter is not needed. So, maximum voltage can be obtained in the load and system complexity is reduced. Maximum power can be obtained from the solar panel by using MPPT. The implementation of MPPT is to operate a PV array under constant voltage and power reference to modify the duty cycle of the inverter.The simulation of proposed topology is done in MATLAB/SIMULINK software.
A Passive Lossless Soft-Switching Snubber for Telecom Power SuppliesIJTET Journal
At present the majority of power supplies or power converters use switch-mode technology. Higher switching frequencies allow reduction of the magnetic component sizes with PWM switching converters but cause higher switching losses and greater electro-magnetic interference. To reduce these switching losses active or passive soft-switching methods are used in various applications.This paper presents a passive lossless soft-switching snubber for telecom power supplies. Simulation results are given to demonstrate the validity and features of the snubber
International Journal of Electrical Engineering and Technology (IJEET) publishes papers on electrical engineering and technology. This paper discusses the design of a single phase Z-source inverter for controlling the speed of an induction motor and powering various loads. A LPC2148 ARM-7 microcontroller generates pulse width modulated signals to control the inverter switches and regulate motor speed based on feedback. Experimental results show the Z-source inverter can efficiently drive different loads including an induction motor.
A Sub-Region Based Space Vector Modulation Scheme for Dual 2-Level Inverter S...IJECEIAES
This paper deals the implementation of 3-level output voltage using dual 2level inverter with control of sub-region based Space Vector Modulation (SR-SVM). Switching loss and voltage stress are the most important issues in multilevel inverters, for keep away from these problems dual inverter system executed. Using this proposed system, the conventional 3-level inverter voltage vectors and switching vectors can be located. In neutral point clamped multilevel inverter, it carries more load current fluctuations due to the DC link capacitors and it requires large capacitors. Based on the subregion SVM used to control IGBT switches placed in the dual inverter system. The proposed system improves the output voltage with reduced harmonic content with improved dc voltage utilisation. The simulation and hardware results are verified using matlab/simulink and dsPIC microcontroller.
Comparison of Sine and Space Vector Modulated Embedded Z-Source Inverter fed ...IAES-IJPEDS
This document compares the performance of a photovoltaic powered embedded Z-source inverter (EZSI) feeding an induction motor drive using either sine pulse width modulation (PWM) or space vector modulation (SVM). An EZSI provides single-stage power conversion from a DC source and can boost the output voltage above the input DC voltage. The document designs, models and simulates a PV-powered EZSI induction motor system in MATLAB/Simulink. The results show this drive system has advantages like voltage boosting ability and reduced harmonic content compared to a traditional voltage source inverter.
Application of SVM Technique for Three Phase Three Leg Ac/Ac Converter TopologyIOSR Journals
This paper presents a simulation of a three-phase three-leg AC/AC converter topology using nine IGBTs and space vector pulse width modulation (SVM) technique. The proposed topology reduces the number of switches compared to conventional back-to-back and matrix converters. Simulation results show the converter provides sinusoidal input and output voltages with unity power factor under constant frequency and variable frequency operation. Experimental results from a 5kVA prototype verify the validity of the proposed scheme.
International Journal of Engineering Research and DevelopmentIJERD Editor
This document summarizes a research paper that proposes a single-phase multilevel inverter topology fed by a photovoltaic panel. The inverter uses a multicarrier phase disposition sinusoidal pulse width modulation scheme to generate gate signals for power switches. It can produce 3, 5, 7, or 9 output voltage levels by controlling the modulation index. The proposed inverter configuration was tested supplying power to an R-L load. Simulation results in MATLAB/Simulink analyzed the performance of the topology and THD values for output current and voltage.
Comparative Evaluation of Generalized Multicell Impedance Source Inverter for...IJPEDS-IAES
Voltage-Source Inverter is limited by its only voltage step-down operation. In adding with extra boosting the flexibility is kept active for the number of semiconductors which is unchanged, voltage-type Z-source inverter was earlier proposed. This new class of inverter is generally less sensitive to electromagnetic noises. However, their boosting capabilities are anyhow less with high component stresses and poorer spectral performances caused by low modulation index ratios. Their boosting gains are, therefore, restricted in practice. To overcome these we use the generalized switched-inductor Z- source inverter is proposed, By comparing with PWM technique and SPWM technique, whose extra boosting abilities and other advantages have been verified in simulation analysis and experiment.
This document presents a comparative investigation of a 7-level cascaded multilevel inverter using different multicarrier pulse width modulation techniques. It discusses the classification, operation, and modulation strategies of multilevel inverters including diode clamped, flying capacitor, and cascaded H-bridge topologies. Simulation results in MATLAB/Simulink are presented to analyze the total harmonic distortion for a 7-level cascaded H-bridge multilevel inverter using phase disposition, alternate phase opposition disposition, and phase opposition disposition pulse width modulation techniques. The research aims to improve the output waveform quality and reduce switching losses of the 7-level inverter.
Simulation of SPWM based Z-Source InverterIOSR Journals
1) The document presents a simulation of a SPWM based Z-source inverter. Z-source inverters can boost or buck the output voltage from a DC supply, overcoming limitations of traditional voltage source inverters.
2) MATLAB/Simulink models were developed for a Z-source inverter feeding resistive, inductive, and motor loads. Simulation results validated that the Z-source inverter has lower total harmonic distortion than traditional voltage source and current source inverters.
3) The Z-source inverter topology was analyzed and its operating principle explained. Sinusoidal pulse width modulation was used for switching control. Simulation results showed improved performance of the Z-source inverter over
IRJET- Study of Unsymmetrical Cascade H-Bridge Multilevel Inverter Design for...IRJET Journal
This document presents a study on an unsymmetrical cascade multilevel inverter design for an induction motor. It discusses using a 7-level and 9-level unsymmetrical cascade multilevel inverter with level shifted pulse width modulation to drive a single phase induction motor. Simulation results in MATLAB/Simulink show that the 9-level inverter produces lower total harmonic distortion in the output voltage compared to the 7-level inverter, with smaller variation in the motor's current, speed, and torque. The study concludes the 9-level inverter provides better performance for driving the induction motor load.
Analysis approach for three phase two level voltage source inverter and five ...eSAT Journals
Abstract
This paper gives idea of comparison of three phase two-level voltage source inverter (TPTLVSI) and five phase two-level voltage
inverter (FPTLVSI) without filter circuit for induction motor drive. The paper demonstrates using mat lab simulations about
comparison in term of harmonics analysis for different firing angles and find best angle suitable for output with minimum harmonics
for FPTLVSI. This paper suggests simulation of comparison point of view three phase two-level voltage inverter (TPTLVSI) and five
phase two-level voltage inverter (FPTLVSI) for induction motor drive.
Index Terms: Modeling of Three phase two-level voltage inverter (TPTLVSI) and five phase two-level voltage inverter
(FPTLVSI)
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.
Similar to IJERD (www.ijerd.com) International Journal of Engineering Research and Development (20)
A Novel Method for Prevention of Bandwidth Distributed Denial of Service AttacksIJERD Editor
Distributed Denial of Service (DDoS) Attacks became a massive threat to the Internet. Traditional
Architecture of internet is vulnerable to the attacks like DDoS. Attacker primarily acquire his army of Zombies,
then that army will be instructed by the Attacker that when to start an attack and on whom the attack should be
done. In this paper, different techniques which are used to perform DDoS Attacks, Tools that were used to
perform Attacks and Countermeasures in order to detect the attackers and eliminate the Bandwidth Distributed
Denial of Service attacks (B-DDoS) are reviewed. DDoS Attacks were done by using various Flooding
techniques which are used in DDoS attack.
The main purpose of this paper is to design an architecture which can reduce the Bandwidth
Distributed Denial of service Attack and make the victim site or server available for the normal users by
eliminating the zombie machines. Our Primary focus of this paper is to dispute how normal machines are
turning into zombies (Bots), how attack is been initiated, DDoS attack procedure and how an organization can
save their server from being a DDoS victim. In order to present this we implemented a simulated environment
with Cisco switches, Routers, Firewall, some virtual machines and some Attack tools to display a real DDoS
attack. By using Time scheduling, Resource Limiting, System log, Access Control List and some Modular
policy Framework we stopped the attack and identified the Attacker (Bot) machines
Hearing loss is one of the most common human impairments. It is estimated that by year 2015 more
than 700 million people will suffer mild deafness. Most can be helped by hearing aid devices depending on the
severity of their hearing loss. This paper describes the implementation and characterization details of a dual
channel transmitter front end (TFE) for digital hearing aid (DHA) applications that use novel micro
electromechanical- systems (MEMS) audio transducers and ultra-low power-scalable analog-to-digital
converters (ADCs), which enable a very-low form factor, energy-efficient implementation for next-generation
DHA. The contribution of the design is the implementation of the dual channel MEMS microphones and powerscalable
ADC system.
Influence of tensile behaviour of slab on the structural Behaviour of shear c...IJERD Editor
-A composite beam is composed of a steel beam and a slab connected by means of shear connectors
like studs installed on the top flange of the steel beam to form a structure behaving monolithically. This study
analyzes the effects of the tensile behavior of the slab on the structural behavior of the shear connection like slip
stiffness and maximum shear force in composite beams subjected to hogging moment. The results show that the
shear studs located in the crack-concentration zones due to large hogging moments sustain significantly smaller
shear force and slip stiffness than the other zones. Moreover, the reduction of the slip stiffness in the shear
connection appears also to be closely related to the change in the tensile strain of rebar according to the increase
of the load. Further experimental and analytical studies shall be conducted considering variables such as the
reinforcement ratio and the arrangement of shear connectors to achieve efficient design of the shear connection
in composite beams subjected to hogging moment.
Gold prospecting using Remote Sensing ‘A case study of Sudan’IJERD Editor
Gold has been extracted from northeast Africa for more than 5000 years, and this may be the first
place where the metal was extracted. The Arabian-Nubian Shield (ANS) is an exposure of Precambrian
crystalline rocks on the flanks of the Red Sea. The crystalline rocks are mostly Neoproterozoic in age. ANS
includes the nations of Israel, Jordan. Egypt, Saudi Arabia, Sudan, Eritrea, Ethiopia, Yemen, and Somalia.
Arabian Nubian Shield Consists of juvenile continental crest that formed between 900 550 Ma, when intra
oceanic arc welded together along ophiolite decorated arc. Primary Au mineralization probably developed in
association with the growth of intra oceanic arc and evolution of back arc. Multiple episodes of deformation
have obscured the primary metallogenic setting, but at least some of the deposits preserve evidence that they
originate as sea floor massive sulphide deposits.
The Red Sea Hills Region is a vast span of rugged, harsh and inhospitable sector of the Earth with
inimical moon-like terrain, nevertheless since ancient times it is famed to be an abode of gold and was a major
source of wealth for the Pharaohs of ancient Egypt. The Pharaohs old workings have been periodically
rediscovered through time. Recent endeavours by the Geological Research Authority of Sudan led to the
discovery of a score of occurrences with gold and massive sulphide mineralizations. In the nineties of the
previous century the Geological Research Authority of Sudan (GRAS) in cooperation with BRGM utilized
satellite data of Landsat TM using spectral ratio technique to map possible mineralized zones in the Red Sea
Hills of Sudan. The outcome of the study mapped a gossan type gold mineralization. Band ratio technique was
applied to Arbaat area and a signature of alteration zone was detected. The alteration zones are commonly
associated with mineralization. The alteration zones are commonly associated with mineralization. A filed check
confirmed the existence of stock work of gold bearing quartz in the alteration zone. Another type of gold
mineralization that was discovered using remote sensing is the gold associated with metachert in the Atmur
Desert.
Reducing Corrosion Rate by Welding DesignIJERD Editor
This document summarizes a study on reducing corrosion rates in steel through welding design. The researchers tested different welding groove designs (X, V, 1/2X, 1/2V) and preheating temperatures (400°C, 500°C, 600°C) on ferritic malleable iron samples. Testing found that X and V groove designs with 500°C and 600°C preheating had corrosion rates of 0.5-0.69% weight loss after 14 days, compared to 0.57-0.76% for 400°C preheating. Higher preheating reduced residual stresses which decreased corrosion. Residual stresses were 1.7 MPa for optimal X groove and 600°C
Router 1X3 – RTL Design and VerificationIJERD Editor
Routing is the process of moving a packet of data from source to destination and enables messages
to pass from one computer to another and eventually reach the target machine. A router is a networking device
that forwards data packets between computer networks. It is connected to two or more data lines from different
networks (as opposed to a network switch, which connects data lines from one single network). This paper,
mainly emphasizes upon the study of router device, it‟s top level architecture, and how various sub-modules of
router i.e. Register, FIFO, FSM and Synchronizer are synthesized, and simulated and finally connected to its top
module.
Active Power Exchange in Distributed Power-Flow Controller (DPFC) At Third Ha...IJERD Editor
This paper presents a component within the flexible ac-transmission system (FACTS) family, called
distributed power-flow controller (DPFC). The DPFC is derived from the unified power-flow controller (UPFC)
with an eliminated common dc link. The DPFC has the same control capabilities as the UPFC, which comprise
the adjustment of the line impedance, the transmission angle, and the bus voltage. The active power exchange
between the shunt and series converters, which is through the common dc link in the UPFC, is now through the
transmission lines at the third-harmonic frequency. DPFC multiple small-size single-phase converters which
reduces the cost of equipment, no voltage isolation between phases, increases redundancy and there by
reliability increases. The principle and analysis of the DPFC are presented in this paper and the corresponding
simulation results that are carried out on a scaled prototype are also shown.
Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVRIJERD Editor
Power quality has been an issue that is becoming increasingly pivotal in industrial electricity
consumers point of view in recent times. Modern industries employ Sensitive power electronic equipments,
control devices and non-linear loads as part of automated processes to increase energy efficiency and
productivity. Voltage disturbances are the most common power quality problem due to this the use of a large
numbers of sophisticated and sensitive electronic equipment in industrial systems is increased. This paper
discusses the design and simulation of dynamic voltage restorer for improvement of power quality and
reduce the harmonics distortion of sensitive loads. Power quality problem is occurring at non-standard
voltage, current and frequency. Electronic devices are very sensitive loads. In power system voltage sag,
swell, flicker and harmonics are some of the problem to the sensitive load. The compensation capability
of a DVR depends primarily on the maximum voltage injection ability and the amount of stored
energy available within the restorer. This device is connected in series with the distribution feeder at
medium voltage. A fuzzy logic control is used to produce the gate pulses for control circuit of DVR and the
circuit is simulated by using MATLAB/SIMULINK software.
Study on the Fused Deposition Modelling In Additive ManufacturingIJERD Editor
Additive manufacturing process, also popularly known as 3-D printing, is a process where a product
is created in a succession of layers. It is based on a novel materials incremental manufacturing philosophy.
Unlike conventional manufacturing processes where material is removed from a given work price to derive the
final shape of a product, 3-D printing develops the product from scratch thus obviating the necessity to cut away
materials. This prevents wastage of raw materials. Commonly used raw materials for the process are ABS
plastic, PLA and nylon. Recently the use of gold, bronze and wood has also been implemented. The complexity
factor of this process is 0% as in any object of any shape and size can be manufactured.
Spyware triggering system by particular string valueIJERD Editor
This computer programme can be used for good and bad purpose in hacking or in any general
purpose. We can say it is next step for hacking techniques such as keylogger and spyware. Once in this system if
user or hacker store particular string as a input after that software continually compare typing activity of user
with that stored string and if it is match then launch spyware programme.
A Blind Steganalysis on JPEG Gray Level Image Based on Statistical Features a...IJERD Editor
This paper presents a blind steganalysis technique to effectively attack the JPEG steganographic
schemes i.e. Jsteg, F5, Outguess and DWT Based. The proposed method exploits the correlations between
block-DCTcoefficients from intra-block and inter-block relation and the statistical moments of characteristic
functions of the test image is selected as features. The features are extracted from the BDCT JPEG 2-array.
Support Vector Machine with cross-validation is implemented for the classification.The proposed scheme gives
improved outcome in attacking.
Secure Image Transmission for Cloud Storage System Using Hybrid SchemeIJERD Editor
- Data over the cloud is transferred or transmitted between servers and users. Privacy of that
data is very important as it belongs to personal information. If data get hacked by the hacker, can be
used to defame a person’s social data. Sometimes delay are held during data transmission. i.e. Mobile
communication, bandwidth is low. Hence compression algorithms are proposed for fast and efficient
transmission, encryption is used for security purposes and blurring is used by providing additional
layers of security. These algorithms are hybridized for having a robust and efficient security and
transmission over cloud storage system.
Application of Buckley-Leverett Equation in Modeling the Radius of Invasion i...IJERD Editor
A thorough review of existing literature indicates that the Buckley-Leverett equation only analyzes
waterflood practices directly without any adjustments on real reservoir scenarios. By doing so, quite a number
of errors are introduced into these analyses. Also, for most waterflood scenarios, a radial investigation is more
appropriate than a simplified linear system. This study investigates the adoption of the Buckley-Leverett
equation to estimate the radius invasion of the displacing fluid during waterflooding. The model is also adopted
for a Microbial flood and a comparative analysis is conducted for both waterflooding and microbial flooding.
Results shown from the analysis doesn’t only records a success in determining the radial distance of the leading
edge of water during the flooding process, but also gives a clearer understanding of the applicability of
microbes to enhance oil production through in-situ production of bio-products like bio surfactans, biogenic
gases, bio acids etc.
Gesture Gaming on the World Wide Web Using an Ordinary Web CameraIJERD Editor
- Gesture gaming is a method by which users having a laptop/pc/x-box play games using natural or
bodily gestures. This paper presents a way of playing free flash games on the internet using an ordinary webcam
with the help of open source technologies. Emphasis in human activity recognition is given on the pose
estimation and the consistency in the pose of the player. These are estimated with the help of an ordinary web
camera having different resolutions from VGA to 20mps. Our work involved giving a 10 second documentary to
the user on how to play a particular game using gestures and what are the various kinds of gestures that can be
performed in front of the system. The initial inputs of the RGB values for the gesture component is obtained by
instructing the user to place his component in a red box in about 10 seconds after the short documentary before
the game is finished. Later the system opens the concerned game on the internet on popular flash game sites like
miniclip, games arcade, GameStop etc and loads the game clicking at various places and brings the state to a
place where the user is to perform only gestures to start playing the game. At any point of time the user can call
off the game by hitting the esc key and the program will release all of the controls and return to the desktop. It
was noted that the results obtained using an ordinary webcam matched that of the Kinect and the users could
relive the gaming experience of the free flash games on the net. Therefore effective in game advertising could
also be achieved thus resulting in a disruptive growth to the advertising firms.
Hardware Analysis of Resonant Frequency Converter Using Isolated Circuits And...IJERD Editor
-LLC resonant frequency converter is basically a combo of series as well as parallel resonant ckt. For
LCC resonant converter it is associated with a disadvantage that, though it has two resonant frequencies, the
lower resonant frequency is in ZCS region[5]. For this application, we are not able to design the converter
working at this resonant frequency. LLC resonant converter existed for a very long time but because of
unknown characteristic of this converter it was used as a series resonant converter with basically a passive
(resistive) load. . Here, it was designed to operate in switching frequency higher than resonant frequency of the
series resonant tank of Lr and Cr converter acts very similar to Series Resonant Converter. The benefit of LLC
resonant converter is narrow switching frequency range with light load[6] . Basically, the control ckt plays a
very imp. role and hence 555 Timer used here provides a perfect square wave as the control ckt provides no
slew rate which makes the square wave really strong and impenetrable. The dead band circuit provides the
exclusive dead band in micro seconds so as to avoid the simultaneous firing of two pairs of IGBT’s where one
pair switches off and the other on for a slightest period of time. Hence, the isolator ckt here is associated with
each and every ckt used because it acts as a driver and an isolation to each of the IGBT is provided with one
exclusive transformer supply[3]. The IGBT’s are fired using the appropriate signal using the previous boards
and hence at last a high frequency rectifier ckt with a filtering capacitor is used to get an exact dc
waveform .The basic goal of this particular analysis is to observe the wave forms and characteristics of
converters with differently positioned passive elements in the form of tank circuits.
Simulated Analysis of Resonant Frequency Converter Using Different Tank Circu...IJERD Editor
LLC resonant frequency converter is basically a combo of series as well as parallel resonant ckt. For
LCC resonant converter it is associated with a disadvantage that, though it has two resonant frequencies, the
lower resonant frequency is in ZCS region [5]. For this application, we are not able to design the converter
working at this resonant frequency. LLC resonant converter existed for a very long time but because of
unknown characteristic of this converter it was used as a series resonant converter with basically a passive
(resistive) load. . Here, it was designed to operate in switching frequency higher than resonant frequency of the
series resonant tank of Lr and Cr converter acts very similar to Series Resonant Converter. The benefit of LLC
resonant converter is narrow switching frequency range with light load[6] . Basically, the control ckt plays a
very imp. role and hence 555 Timer used here provides a perfect square wave as the control ckt provides no
slew rate which makes the square wave really strong and impenetrable. The dead band circuit provides the
exclusive dead band in micro seconds so as to avoid the simultaneous firing of two pairs of IGBT’s where one
pair switches off and the other on for a slightest period of time. Hence, the isolator ckt here is associated with
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IJERD (www.ijerd.com) International Journal of Engineering Research and Development
1. International Journal of Engineering Research and Development
e-ISSN: 2278-067X, p-ISSN: 2278-800X, www.ijerd.com
Volume 2, Issue 11 (August 2012), PP. 51-59
Maximum Boost control of Cascaded MultiLevel Z-Source
Inverter for Fuel Cell Applications
Dr.R.Seyezhai1, Dr.B.L.Mathur2 & A.ShanmugaPriyaa3
1
Associate Professor, 2Professor & 3PG Scholar,
Department of EEE, SSN College of Engineering, Chennai, India
Abstract––In this paper, a cascaded five level Z-Source inverter is proposed for fuel cell applications. The proposed
topology employs Z network between the DC source and inverter circuitry to achieve boost operation. The output voltage
of proposed inverter can be controlled using modulation index and shoot through state. Various modulation strategies
have been reported in the literature for the proposed topology. But this paper focuses on the implementation of maximum
boost control with third harmonic injection which turns all traditional zero states into shoot-through states. The
performance parameters of Z-Source cascaded Multilevel inverter is computed and compare with simple boost method.
Simulations of the circuit configuration of the control methods have been performed in MATLAB/Simulink and the
results are verified.
Keywords––Cascaded Z-source Multilevel Inverter, Maximum boost control, voltage stress & voltage gain..
I. INTRODUCTION
In recent years, the multilevel voltage inverter is widely used in high power applications such as large induction
motor drives, UPS systems and Flexible AC Transmission Systems (FACTS). Multilevel inverter obtains a desired output
voltage from several levels of input DC voltage sources. With an increasing number of DC voltage sources, the inverter
voltage output waveform level increases. As compared to traditional two level inverters, the multilevel inverters have more
advantages which include lower semiconductor voltage stress, better harmonic performance, low Electro Magnetic
Interference (EMI) and lower switching losses. Despite these advantages, multilevel inverters output voltage amplitude is
limited to DC sources voltage summation. Occurring of short circuit can destroy multilevel inverters. To solve these
problems, cascaded multilevel Z-source inverter [1-2] is proposed in this paper. The performance of the inverter is analyzed
by employing a maximum boost control with third harmonic injection PWM technique. Maximum boost control converts all
traditional zero states to shoot through while maintaining the active states. In this technique, the shoot through duty ratio
varies during each cycle and maximum gain is obtained. Simple boost and maximum boost control methods for the proposed
inverter topology are analyzed and compared .The effect of voltage gain and voltage stress for various modulation indices is
studied for both the methods and the results are verified.
II. CASCADED MULTILEVEL Z-SOURCE INVERTER
The circuit diagram of cascaded Z-Source five-level inverter is shown in Fig.1. It consists of a series single phase
H bridge inverter units, Z impedances and DC voltage sources. DC sources can be obtained from batteries, fuel cells, solar
cells [1]. Each H-bridge Z-Source inverter can generate three different output voltage +Vin, 0, -Vin. Output voltage can be
higher than the input voltage when boost factor, B>1.The number of output voltage levels, m in this topology is given by (n-
1)/2, where n is the number of Z impedances or DC voltage sources. This topology has an extra switching state: shoot
through state as compared to cascaded H-bridge inverters. During the shoot-through state, the output voltages of Z networks
are zero [3].
51
2. Maximum Boost control of Cascaded MultiLevel Z-Source Inverter for Fuel Cell Applications
Fig.1.Five-level cascaded Z-source Multilevel Inverter
Circuit operation consists of two modes namely shoot -through and non shoot-through states [2]. In Shoot-Through
(ST) switching state of Z-Source MLI, upper and lower bridges of the same leg is turned on having the output voltage of
zero .During non shoot-through state opposite pairs of legs of both the bridge conducts. In ST state the two inductors are
being charged by the capacitors and in Non-Shoot-Through (NST) states the inductors and input DC source transfer energy
to the capacitors and load. This process is similar to the boost converter. Output voltage depends on the boost factor. The
conduction table is shown in table –I
Table –I Conduction Table for Cascaded Multilevel Z-source Inverter
VOLTAGE LEVEL OUTPUT VOLTAGE ON SWITCHES
Level 2 (non shoot-through) 2Vin S3,S4,S5 ,S6
Level 1 (non shoot-through) Vin S1,S3,S5 ,S6
Level 1 (shoot-through) Vin S1,S2, S3, S4, S5, S6
Level 1 (non shoot-through) Vin S3,S4,S5 ,S7
Level 1 (shoot-through) Vin S3,S4,S5 ,S6, S7, S8
Level 0 (zero state) 0 (V) S1,S3,S5 ,S7
Level 0 (shoot-through) 0 (V) S1,S2,S3 ,S4,S5,S7
Level 0 (shoot-through) 0 (V) S1,S3,S5 ,S6,S7,S8
Level -1 (non shoot-through) -Vin S1,S3,S7 ,S8
Level -1 (shoot-through) -Vin S1, S2, S3, S4, S7,S8
Level -1 (non shoot-through) -Vin S1,S2,S5 ,S7
Level -1 (shoot-through) -Vin S1, S2, S5, S6, S7,S8
Level -2 (non shoot-through) -2Vin S1,S2,S7,S8
III. MAXIMUM BOOST CONTROL WITH THIRD HARMONIC INJECTION
A simple third harmonic injection method is therefore presented to provide the waveform with high quality . the
reference waveform consists of both fundamental component and third harmonic component. The sinusoidal reference signal
can be injected by a third harmonic with a magnitude equal to 25% of the fundamental. As a result, the peak-to-peak
amplitude of the resulting reference function does not exceed the DC supply voltage Vs, but the fundamental component is
higher than the available supply Vs. This eliminates third and multiples of third order harmonics which leads to reduction in
Total Harmonic Distortion it is observed that Third harmonic injection PWM technique gives high voltage gain and reduced
THD. Inductor current ripple and capacitor voltage ripple of Z-Source cascaded inverter are also reduced. Therefore, third
harmonic injection PWM technique. Maximum boost control with third harmonic injection turns all traditional zero states
52
3. Maximum Boost control of Cascaded MultiLevel Z-Source Inverter for Fuel Cell Applications
into shoot-through state [4-6]. The voltage stress across the switching devices is greatly reduced by fully utilizing the zero
states. Turning all zero states into shoot-through state can minimize the voltage stress and this causes a shoot-through duty
ratio varying in a line cycle, which causes inductor current ripple.
Maximum shoot-through boost factor can be written as,
1
B (1)
1 2D
Where B is boost factor and D is duty ratio which is given by
2 3 3
D
2 (2)
The circuit is in shoot through state when the triangular carrier wave is either greater than the maximum curve of
the reference signals or smaller than the minimum of the references [7,8]. The shoot-through duty cycle varies each cycle.
The shoot-through state repeats periodically in every п/3 degrees. Fig.2 shows the reference and carrier waveforms for
maximum boost control with third harmonic injection PWM technique. The circuit is in shoot through state when the
triangular carrier wave is either greater than the maximum curve of the reference signals or smaller than the minimum of the
references. The shoot-through duty cycle varies each cycle.
Fig.2 Maximum Boost control with third harmonic injection
Fig.3 shows Matlab/ Simulink of Z-Source cascaded MLI using Unipolar PWM with Boost factor = 1.25, ma = 0.8,
RL Load where R=50Ω and L=24mH, Input voltage Vdc=75V, Z impedances, L1 = L2 = L3 = L4 = L = 40mH and C1 = C2 =
C3 = C4 = 6600µF. Simulink circuit is shown with LC filter having L=30mH and C=150µF.
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4. Maximum Boost control of Cascaded MultiLevel Z-Source Inverter for Fuel Cell Applications
Fig 3 MATLAB/ SIMULINK circuit of Z-Source cascaded MLI using Maximum Boost control
IV. SIMULATION OF CASCADED Z-SOURCE INVERTER USING MAXIMUM BOOST
CONTROL WITH THIRD HARMONIC INJECTION
The simulation results for the Z-source MLI with maximum boost control is shown in Figs.4,5 &6.
Fig.4 Load voltage waveform for maximum boost control with Third Harmonic injection PWM without
filter (Boost factor: 3.09, ma= 0.8, RL Load)
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5. Maximum Boost control of Cascaded MultiLevel Z-Source Inverter for Fuel Cell Applications
Fig 5. Filtered output voltage waveform for Z-Source MLI
Fig .6 Filtered output current waveform for Z-Source MLI
Performance parameters of Z -Source multilevel Inverter are analyzed for various control methods which are
implemented using third harmonic injection PWM technique [9-12]. Performance parameters are Total Harmonic Distortion,
inductor current ripple of Z-Source inverter, capacitor voltage ripple of Z-Source inverter, voltage gain and voltage stress.
Total Harmonic Distortion of five level Z-Source inverter is analyzed and compared for control methods- -simple boost
control and maximum boost control. THD is calculated for various modulation index values and the comparison is shown in
Fig.7.
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6. Maximum Boost control of Cascaded MultiLevel Z-Source Inverter for Fuel Cell Applications
Fig .7 Effect of modulation index on Total Harmonic Distortion for three control techniques
From Fig .7, it can be concluded that the maximum boost control technique has reduced THDv compared to
simple boost for ma=0.8. Inductor current ripple is calculated across the inductor of z impedance of Z-Source inverter.
Inductor current ripple is shown in table for various modulation strategies that changes with variation in modulation indices.
Table I Effect of modulation index on inductor current ripple for three control techniques
S.N0 m SIMPLE BOOST MAXIMUM
a
CONTROL METHOD BOOST CONTROL
METHOD
1 0.8 0.5 0.0598
2 0.73 0.6191 0.0680
3 0.67 0.7 0.0796
From the Table I, it is clear that maximum boost control has less inductor current ripple than simple boost control method.
Capacitor voltage ripple is calculated across the capacitor of z impedance of Z-Source inverter. Capacitor voltage ripple is
shown in table -II for various modulation strategies that changes with variation in modulation indices.
Table II Effect of modulation index on Capacitor voltage ripple for three control techniques
S.N0 m SIMPLE BOOST MAXIMUM BOOST
a
CONTROL CONTROL METHOD
METHOD
1 0.8 0.0414 0.1138
2 0.73 0.0362 0.8718
3 0.67 0.0230 0.8571
From the Table II, maximum boost control has the least capacitor voltage ripple which reduces the cost of the capacitor used.
Voltage gain, G is calculated for various modulation strategies. In Fig.8, voltage gain in compared with different modulation
indices for all modulation techniques. Voltage gain, G is given by [13,14],
2Vac
G (3)
Vin
where, Vac=RMS value of output voltage
Vin=Input voltage
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7. Maximum Boost control of Cascaded MultiLevel Z-Source Inverter for Fuel Cell Applications
From the Fig 8 , maximum boost control technique has higher voltage gain compared to simple boost control method for
ma=0.8.
Fig 8 Effect of modulation index on voltage gain for three control techniques
In Figures 8, 9 and 10, voltage stress in compared with voltage gain for various modulation techniques. Voltage Stress is
calculated from voltage gain as shown in equations (4-6). Voltage stress is given by [15],
1
Simple boost control: - VS = 2 (4)
G
1
Maximum boost control: - VS = 3 (5)
G
Maximum constant boost control: - VS = (6)
3 3G
Where, G=Voltage gain
Fig.9 to Fig.10 shows variation of voltage stress with voltage gain(G) for all three techniques.
Fig 9 Effect of voltage gain on voltage stress for simple boost control method
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8. Maximum Boost control of Cascaded MultiLevel Z-Source Inverter for Fuel Cell Applications
Fig 10 Effect of voltage gain on voltage stress for maximum boost control method
Table –III COMPARISON TABLE FOR THE CONTROL METHODS
S. PARAMETERS SIMPLE BOOST MAXIMUM
N CONTROL BOOST
O METHOD CONTROL
METHOD
1 THDv 6.78 5.58
2 THDi 6.62 5.16
3 Ripple in 0.0414 0.1138
capacitor voltage
4 Ripple in inductor 0.5 0.0598
current
5 Voltage gain(G) 9.107 20
6 Voltage stress 1.89 2.03
7 Boost factor(B) 1.25 3.09
From the Table III, it is observed that the maximum boost control method has less Capacitor voltage ripple which
reduces the cost of the capacitor used and gives high voltage gain (G) and reduced voltage stress (V S) compared to simple
boost control.Inductor rating of maximum boost control method is reduced with third harmonic injection PWM technique
and also ripple in the output current reduces thus reducing the cost of the filter. With this maximum boost control method,
THD of the output voltage waveform has been reduced. Therefore maximum boost control method is preferred for the
proposed topology.
V. CONCLUSION
This paper provides a clear overview on control techniques used in z-source multilevel inverters. It has been found
that the maximum boost control method yields better results when compared to maximum boost control method. By
employing the maximum boost control technique THD of the output voltage is reduced , inductor rating is reduced with
third harmonic injection PWM technique, capacitor voltage ripple is less which reduces the cost of the capacitor used, ripple
in the output current reduces thus reducing the cost of the filter , high voltage gain (G) and reduced voltage stress V S. The
impact of third harmonic injection has eliminated 3rd order harmonic and multiples of 3rd order harmonics there by reducing
the output voltage THD (THDv) and output current THD (THDi).
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Biography
Dr.R.Seyezhai obtained her B.E. (Electronics & Communication Engineering) from Noorul Islam
College of Engineering, Nagercoil in 1996 and her M.E in Power Electronics & Drives from Shanmugha
College of Engineering, Thanjavur in 1998 and Ph.D from Anna University, Chennai, in 2010. She has
been working in the teaching field for about 14 Years. She has published 100 papers in the area of
Power Electronics & Drives. Her areas of interest include SiC Power Devices & Multilevel Inverters.
Dr.B.L.Mathur obtained his B.E. (Electrical Engineering) from University of Rajasthan, in 1962 and
his M.Tech in Power Systems from IIT, Bombay in 1964.He completed his Ph.D. in 1979 from IISc,
Bangalore. His Ph.D. thesis was adjudged as the best for application to industries in the year 1979 and
won gold medal. He has been working in the teaching field for about 44 Years. He takes immense
interest in designing Electronic circuits. He has published 50 papers in National and International
journals and 85 in National and International conferences. His areas of interest include Power Devices,
Power Converters, Computer Architecture and FACTS.
A.Shanmuga priyaa obtained her B.E. (Electrical & Electronics Engineering) from St.Josephs College
of Engineering, chennai in 2010 and presently doing her IInd year M.E in Power Electronics & Drives
in SSN College of Engineering, Chennai.Her areas of interest include Power electronics & Multilevel
Inverters.
59