This document summarizes a research paper on a new three phase seven level asymmetrical inverter with hybrid carrier and third harmonic reference. It proposes a novel carrier based pulse width modulation technique that uses a combination of an inverted sine carrier and triangular carrier (hybrid carrier) to produce switch pulses for the inverter. It investigates this hybrid carrier technique for a three phase cascaded multilevel inverter, evaluating performance based on total harmonic distortion, output voltage RMS value, and DC bus utilization. The document outlines different carrier-based PWM strategies like phase disposition, phase opposition disposition, and alternate phase opposition disposition that are evaluated in the research.
Analysis of Binary DC Source Reduced Switch 7-level InverterIAES-IJPEDS
This document analyzes a binary DC source reduced switch 7-level inverter using unipolar PWM control strategies. It proposes a 7-level inverter topology with two DC sources and reduced switching devices. The inverter is simulated in MATLAB/Simulink using three unipolar PWM strategies - phase disposition, alternate phase opposition disposition, and carrier overlapping with sinusoidal and trapezoidal references. Performance is evaluated for total harmonic distortion, output voltage, crest factor, and distortion factor for modulation indices from 0.7 to 1. It is observed that phase disposition PWM with trapezoidal reference provides the lowest distortion while carrier overlapping PWM with trapezoidal reference provides the highest fundamental output voltage.
A Overlapping Carrier Based SPWM for a 5-Level Cascaded H-bridge Multilevel I...IJPEDS-IAES
This paper proposes a switching control for a cascaded H-bridge inverter
structure with reduced switches which is used to improve the THD
performance of a single phase five level CHB MLI. The multi level inverter
is simulated for the conventional carrier overlapping APOD and the proposed
carrier overlapping APOD pulse width modulation (PWM) switching control
technique. The total harmonic distortion (THD) of the output voltages are
observed for both PWM control techniques. The performance of the
symmetric CHB MLI is simulated using MATLAB/Simulink. It is observed
that the proposed carrier overlapping APODPWM provides output with
relatively low THD as compared to the conventional carrier overlapping
APODPWM.
This document presents a performance analysis of multicarrier sinusoidal pulse width modulation (MCSPWM) strategies for a three-phase seven-level Z-source cascaded inverter. It describes the topology of the Z-source seven-level cascaded inverter and discusses five different MCSPWM strategies: phase disposition, phase opposition disposition, alternate phase opposition disposition, carrier overlapping, and variable frequency. Simulation results in MATLAB/Simulink are presented to analyze the output voltage waveform and total harmonic distortion for each strategy at different modulation indices. The phase opposition disposition strategy provided the lowest THD and highest fundamental output voltage.
This document summarizes research on a single-phase five-level diode-clamped multilevel inverter (DCMLI). It first describes the conventional DCMLI topology using four capacitors and eight switches to achieve five voltage levels. It then introduces the topology studied in the paper, which uses only two capacitors and eight switches by incorporating two H-bridge legs. Simulation results are presented comparing the performance of the inverter under different pulse width modulation techniques, evaluating metrics like total harmonic distortion, voltage waveform quality factors, and efficiency of utilizing the DC bus voltage. Sinusoidal pulse width modulation with phase opposition and disposition modulation is found to provide the lowest output voltage distortion.
This document presents research on a cascaded nine-level inverter using pulse width modulation (PWM) and hybrid PWM techniques. It describes the topology and operation of a cascaded multilevel inverter using H-bridge cells. Phase shifted PWM and a hybrid modulation strategy are analyzed for controlling the inverter. Simulation results show the line voltage, phase voltage, and load current waveforms for both modulation methods. Total harmonic distortion is calculated, showing 17.44% for phase shifted PWM and 9.92% for hybrid PWM modulation. The hybrid method achieves lower distortion by operating higher voltage cells at lower switching frequencies.
Performance Evaluation of a Three Phase Nine Level Inverter with Reduced Swit...Scientific Review
This paper presents a three phase nine level cascaded H-bridge (CHB) multilevel inverter with RL load. A sinusoidal and trapezoidal PWM method is used to achieve minimum total harmonics distortion (THD) in the output current of multilevel inverters. The analysis of the output current harmonics is carried out and compared with the seven level conventional cascaded H-bridge inverters. The proposed inverter is verified through simulation and the simulation results are compared with the conventional multilevel inverter. From the result the proposed inverter offers much less total harmonic distortion.
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.
Investigation of THD for Cascaded Multi-Level Inverter Using Multicarrier Mod...IJERA Editor
This document summarizes an investigation into the total harmonic distortion (THD) of cascaded multi-level inverters using different multicarrier modulation techniques. It describes three modulation techniques - phase shifted multicarrier modulation (PSHM), level shifted multicarrier modulation (LSHM), and wave level shifted multicarrier modulation (WLSHM). Simulation results for 7-level, 9-level, 11-level, and 13-level inverters show that WLSHM achieves the lowest THD compared to the other techniques. The document concludes that WLSHM is the best modulation method for reducing THD in cascaded multi-level inverters.
Analysis of Binary DC Source Reduced Switch 7-level InverterIAES-IJPEDS
This document analyzes a binary DC source reduced switch 7-level inverter using unipolar PWM control strategies. It proposes a 7-level inverter topology with two DC sources and reduced switching devices. The inverter is simulated in MATLAB/Simulink using three unipolar PWM strategies - phase disposition, alternate phase opposition disposition, and carrier overlapping with sinusoidal and trapezoidal references. Performance is evaluated for total harmonic distortion, output voltage, crest factor, and distortion factor for modulation indices from 0.7 to 1. It is observed that phase disposition PWM with trapezoidal reference provides the lowest distortion while carrier overlapping PWM with trapezoidal reference provides the highest fundamental output voltage.
A Overlapping Carrier Based SPWM for a 5-Level Cascaded H-bridge Multilevel I...IJPEDS-IAES
This paper proposes a switching control for a cascaded H-bridge inverter
structure with reduced switches which is used to improve the THD
performance of a single phase five level CHB MLI. The multi level inverter
is simulated for the conventional carrier overlapping APOD and the proposed
carrier overlapping APOD pulse width modulation (PWM) switching control
technique. The total harmonic distortion (THD) of the output voltages are
observed for both PWM control techniques. The performance of the
symmetric CHB MLI is simulated using MATLAB/Simulink. It is observed
that the proposed carrier overlapping APODPWM provides output with
relatively low THD as compared to the conventional carrier overlapping
APODPWM.
This document presents a performance analysis of multicarrier sinusoidal pulse width modulation (MCSPWM) strategies for a three-phase seven-level Z-source cascaded inverter. It describes the topology of the Z-source seven-level cascaded inverter and discusses five different MCSPWM strategies: phase disposition, phase opposition disposition, alternate phase opposition disposition, carrier overlapping, and variable frequency. Simulation results in MATLAB/Simulink are presented to analyze the output voltage waveform and total harmonic distortion for each strategy at different modulation indices. The phase opposition disposition strategy provided the lowest THD and highest fundamental output voltage.
This document summarizes research on a single-phase five-level diode-clamped multilevel inverter (DCMLI). It first describes the conventional DCMLI topology using four capacitors and eight switches to achieve five voltage levels. It then introduces the topology studied in the paper, which uses only two capacitors and eight switches by incorporating two H-bridge legs. Simulation results are presented comparing the performance of the inverter under different pulse width modulation techniques, evaluating metrics like total harmonic distortion, voltage waveform quality factors, and efficiency of utilizing the DC bus voltage. Sinusoidal pulse width modulation with phase opposition and disposition modulation is found to provide the lowest output voltage distortion.
This document presents research on a cascaded nine-level inverter using pulse width modulation (PWM) and hybrid PWM techniques. It describes the topology and operation of a cascaded multilevel inverter using H-bridge cells. Phase shifted PWM and a hybrid modulation strategy are analyzed for controlling the inverter. Simulation results show the line voltage, phase voltage, and load current waveforms for both modulation methods. Total harmonic distortion is calculated, showing 17.44% for phase shifted PWM and 9.92% for hybrid PWM modulation. The hybrid method achieves lower distortion by operating higher voltage cells at lower switching frequencies.
Performance Evaluation of a Three Phase Nine Level Inverter with Reduced Swit...Scientific Review
This paper presents a three phase nine level cascaded H-bridge (CHB) multilevel inverter with RL load. A sinusoidal and trapezoidal PWM method is used to achieve minimum total harmonics distortion (THD) in the output current of multilevel inverters. The analysis of the output current harmonics is carried out and compared with the seven level conventional cascaded H-bridge inverters. The proposed inverter is verified through simulation and the simulation results are compared with the conventional multilevel inverter. From the result the proposed inverter offers much less total harmonic distortion.
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.
Investigation of THD for Cascaded Multi-Level Inverter Using Multicarrier Mod...IJERA Editor
This document summarizes an investigation into the total harmonic distortion (THD) of cascaded multi-level inverters using different multicarrier modulation techniques. It describes three modulation techniques - phase shifted multicarrier modulation (PSHM), level shifted multicarrier modulation (LSHM), and wave level shifted multicarrier modulation (WLSHM). Simulation results for 7-level, 9-level, 11-level, and 13-level inverters show that WLSHM achieves the lowest THD compared to the other techniques. The document concludes that WLSHM is the best modulation method for reducing THD in cascaded multi-level inverters.
Multilevel inverters play a crucial part in the
areas of high and medium voltage applications. Among the three
main multilevel inverters used, the capacitor clamped multilevel
inverter(CCMLI) has advantage with respect to voltage
redundancies. This work proposes a switching pattern to improve
the performance of chosen H-bridge type CCMLI over
conventional CCMLI. The PWM technique used in this work is
Phase Opposition Disposition PWM(PODPWM). The
performance of proposed H-bridge type CCMLI is verified
through MATLAB-Simulink based simulation. It has been
observed that the THD is low in chosen CCMLI compared to
conventional CCMLI.
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.
ENHANCEMENT OF FUNDAMENTAL RMS OUTPUT VOLTAGE OF 5-LEVEL CASCADED H-BRIDGE MU...IAEME Publication
Cascaded H-bridge Multilevel Inverter (CHBMLI) is the most suitable topology for the PV power converters. In this paper an effort has been made to increase the performance of CHBMLI by improving the fundamental Root Mean Square (RMS) value of the output voltage. This work proposes a Modified Multi Carrier PWM (MMCPWM) technique where, reference sine wave has been replaced by ellipse wave, resulting in enhanced performances on the fundamental rms output voltage and lower Total Harmonic Distortion (THD). Analysis of single phase 5-level CHBMLI with and without load are carried for the different Multi Carrier PWM (MCPWM) techniques.
Improved performance with fractional order control for asymmetrical cascaded ...journalBEEI
This document discusses improving the performance of an asymmetrical cascaded H-bridge multilevel inverter (ACHBMLI) using fractional order control. A fractional order PID (FO-PID) controller is designed for a seven-level ACHBMLI using a simplified small signal model. Simulation results show the FO-PID controller maintains the output voltage closer to the reference voltage and reduces harmonic distortion compared to a conventional PID controller. The FO-PID controller provides improved robustness over a conventional PID controller for the ACHBMLI.
ANALYSIS AND IMPLEMENTATION OF FPGA CONTROL OF ASYMMETRIC MULTILEVEL INVERTER...IJAMSE Journal
This paper presents an Asymmetric Multilevel Inverter (AMLI) with reduced number of switches for fuel
cells and suitable for high voltage and high power applications. Among the several types of multilevel
inverter, AMLI is a suitable choice to generate the higher number of output voltage levels with fewer
switches and sources. A novel hybrid modulation strategy based on Variable Amplitude Phase Opposition
and Disposition (VAPOD) is implemented using FPGA for AMLI which is powered by Proton Exchange
Membrane Fuel Cell (PEMFC). The operation of the proposed AMLI is verified with simulation and
experimental results.
Multilevel Inverters are getting popular and have become more attractive to researchers in the recent times for high power applications due to their better power quality and higher efficiency as compared to two level inverters. This research work presents a detailed comparative analysis of various multicarrier sinusoidal PWM schemes such as In Phase Disposition, Phase Opposition Disposition and Alternate Phase Opposite Disposition implemented on five level conventional and modified cascaded h-bridge inverters in MATLAB/SIMULINK software. Conventional five level topology uses eight switches and suffers from increased switching complexity while modified five level topology uses only five switches and is recommended to reduce switching complexity and switching losses. It also ensures less number of components, reduced size and overall cost of the system. The effect of modulation index (Ma) on the output harmonic contents in various PWM techniques is also analyzed.
This document summarizes a research paper that proposes and analyzes a multilevel line-commutated inverter topology for solar PV-based grid-connected inverters. The proposed topology uses a multi-winding transformer to provide multiple voltage levels and reduce harmonic distortion in the line current compared to a conventional square-wave inverter. A three-level implementation is modeled in Simulink and experimentally tested. Simulation and experimental results show the proposed topology reduces total harmonic distortion and improves power transfer characteristics compared to a conventional line-commutated inverter.
1) The document describes the analysis and simulation of an interleaved buck converter for automotive dual voltage systems. An interleaved six-phase buck converter is modeled and simulated in Simulink.
2) The interleaved topology provides benefits like reduced output ripple, smaller filter requirements, and improved reliability compared to a single phase buck converter.
3) Components like inductors, capacitors, and MOSFET switches are selected based on specifications such as a 1kW power rating and 71A output current. Simulation results are used to verify the effectiveness of the converter design.
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.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Experimental Validation of Shared Inverter Topology to Drive Multi AC-Loads IJECEIAES
Many reduced-switch-count (RSC) inverter topologies have been proposed in the literature. As the number of switches required to produce a set of voltages in RSC inverters are less than that in conventional inverter, as a result utilizing RSC inverters in a certain system reduces its size and cost. In this paper, a novel RSC shared inverter topology consisting of fifteen switches and capable of driving four three-phase AC-loads independently is proposed and experimentally verified. A carrier-based pulse width modulation (PWM) technique that employs the zero-sequence-signal injection principle is developed to drive the proposed inverter along with adequate DC voltage bus utilization between the shared loads for common frequency (CF) as well as different frequency (DF) modes. The structure and the principle of operation of the proposed inverter are introduced and intensively verified using simulation and field-programmable-gate-array (FPGA)-in-the-loop simulation under linear and nonlinear loads. Then, Inverter prototype was built and the proposed inverter has been verified experimentally. The experimental results verify the applicability of the proposed inverter and the employed PWM.
The conventional three-level inverter has been proposed to act as a recuperating converter in Traction Supply Substation. This converter is mainly used to feed back the regenerative braking energy to the grid. However, passive filter is desired to mitigate the current and voltage harmonics. Therefore, this paper investigates the possibility to use a seven-level Cascaded H-Bridge (CHB) converter as the recuperating converter without additional filtering. The proposed converter is modeled with MATLAB/Simulink simulation software. It is then simulated with two potential modulation schemes, namely Phase-Shifted PWM (PS-PWM) and Phase-Disposition PWM (PD-PWM). The quality of AC waveforms produced by these two modulation methods is compared and studied. The results show that PS-PWM technique is preferable for this application as it offered a clean AC current waveform with less than 5% harmonic distortion. However, a twenty-one-level CHB was predicted to comply with the 8% voltage harmonic requirement.
This document presents a single-stage isolated bi-directional converter topology using a high frequency AC link for charging and vehicle-to-grid applications of plug-in hybrid electric vehicles. The converter consists of two active bridges connected by a series resonant tank and high-frequency transformer. Steady-state analysis is presented to show how phase-shift modulation between the active bridges can control bidirectional power flow. Simulation results are provided to validate the analysis. The proposed converter has the advantages of minimal conversion stages, high switching frequency operation, and low switching losses.
A Novel Hybrid Negative Half Cycle Biased Modulation Scheme for Cascaded Mult...IJPEDS-IAES
This paper proposes a new Modified hybrid modulation scheme for cascaded multilevel inverter. The proposed method employs novel single carrier sinusoidal pulse width modulation with its negative cycle biased (HNHCBM) for reducing switching losses when compared to other sinusoidal modulation methods using a hybrid scheme. This scheme is a derivative of various single carrier sinusoidal pulse width modulation scheme and main advantages are reduced harmonics, enhanced output voltage, reduced power loss in the series cells and ease of implementation. The simulation results are analysed with matlab/simulink and compared with experimental results obtained using 5-level inverter and the results are summarized.
Common Mode Voltage reduction in Diode Clamped MLI using Alternative Phase Op...Mohd Esa
The main objective of this paper is to reduce the Common Mode Voltage (CMV) in the Diode Clamped Multilevel Inverter (DCMLI).Three phase Y-connected RL load is connected to DCMLI. The common mode voltage exists between neutral point of Y-connected load and system ground.CMV causes premature failure of bearings of induction motor and is essential to reduce. In this paper, Alternative Phase Opposition Disposition SPWM technique is used to reduce common mode voltage. Two level, five level, seven level and nine level DCMLI are compared in terms of THD and CMV.The effect of a passive LC filter on THD was studied. The simulation of circuit is carried out by using MATLAB/Simulink. Simulation result portrays reduction in THD and CMV by using APOD-SPWM controlled higher level Inverters.
INVESTIGATION OF COMMON MODE VOLTAGE IN 5-LEVEL DIODE CLAMPED MLI USING CARRI...Mohd Esa
The main aim of this paper is to investigate the Common Mode Voltage (CMV) and Total Harmonic Distortion (THD) in five level Diode Clamped Inverter using Carrier based SPWM techniques. The common mode voltage exists between neutral point of star connected load and system ground. Various Carrier based SPWM techniques used to analyze CMV and THD in this paper are Phase Disposition (PD) strategy, Phase Opposition Disposition (POD) strategy, Alternative Phase Opposition Disposition (APOD) strategy, Carrier Overlap Phase Disposition (COPD) Strategy, Carrier Overlap Phase Opposition Disposition (COPOD) strategy and Carrier Overlap Alternative Phase Opposition Disposition (COAPOD) strategy.RL load is connected to inverter circuit for analysis purpose and Simulation is performed using MATLAB/Simulink Software.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
PERFORMANCE INVESTIGATION OF ASYMMETRIC MULTILEVEL INVERTER WITH REDUCED SWIT...ecij
This paper investigates the performance of Asymmetric Multilevel Inverter (AMLI) with reduced number of switches for fuel cell applications. The proposed topology generates fifteen-level output with improved spectral quality of the output. Moreover, a novel hybrid modulation strategy based on Variable Amplitude Phase Opposition Disposition (VAPOD) technique is implemented. The proposed topology is powered by PEM fuel cell source which is modeled in MATLAB. The performance parameters such as Total Harmonic Distortion (THD), Weighted THD (WTHD), Harmonic Spread Factor (HSF) and Distortion Factor (DF) are computed to verify the performance of the proposed topology. Circuit simulation studies are carried out in MATLAB/SIMULINK software and the results are verified.
Implementation of High Throughput Radix-16 FFT ProcessorIJMER
The extension of radix-4 algorithm to radix-16 to achieve the high throughput of 2.59 giga-samples/s for WPAN’s.We are also reformulating radix-16 algorithm to achieve low-complexity and
low area cost and high performance. Radix-16 FFT is obtained by cascaded the radix -4 butterfly
units. It facilitates low-complexity realization of radix-16 butterfly operation and high operation speed
due to its optimized pipelined structure. Besides, a new three-stage multiplier for twiddle factor
multiplication is also proposed, which has lower area and power consumption than conventional
complex multipliers
Analysis and Performance evaluation of Traditional and Hierarchal Sensor NetworkIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
The Three Phases of the Anti-Christ PowerRobert Taylor
This document outlines keys to unlocking prophecies in the Bible. It discusses various symbols found in prophecies and their meanings, such as beasts representing ruling powers. It analyzes prophecies about a beast with seven heads and ten horns in Revelation 12-13 and 17. This beast represents the papacy, which ruled as a head/empire for 1260 years before being wounded but healing. Biblical knowledge of the antichrist power and its mark are said to be the last message before Jesus' return. Intellectual biblical knowledge is presented as the greatest reformer of Christianity.
Multilevel inverters play a crucial part in the
areas of high and medium voltage applications. Among the three
main multilevel inverters used, the capacitor clamped multilevel
inverter(CCMLI) has advantage with respect to voltage
redundancies. This work proposes a switching pattern to improve
the performance of chosen H-bridge type CCMLI over
conventional CCMLI. The PWM technique used in this work is
Phase Opposition Disposition PWM(PODPWM). The
performance of proposed H-bridge type CCMLI is verified
through MATLAB-Simulink based simulation. It has been
observed that the THD is low in chosen CCMLI compared to
conventional CCMLI.
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.
ENHANCEMENT OF FUNDAMENTAL RMS OUTPUT VOLTAGE OF 5-LEVEL CASCADED H-BRIDGE MU...IAEME Publication
Cascaded H-bridge Multilevel Inverter (CHBMLI) is the most suitable topology for the PV power converters. In this paper an effort has been made to increase the performance of CHBMLI by improving the fundamental Root Mean Square (RMS) value of the output voltage. This work proposes a Modified Multi Carrier PWM (MMCPWM) technique where, reference sine wave has been replaced by ellipse wave, resulting in enhanced performances on the fundamental rms output voltage and lower Total Harmonic Distortion (THD). Analysis of single phase 5-level CHBMLI with and without load are carried for the different Multi Carrier PWM (MCPWM) techniques.
Improved performance with fractional order control for asymmetrical cascaded ...journalBEEI
This document discusses improving the performance of an asymmetrical cascaded H-bridge multilevel inverter (ACHBMLI) using fractional order control. A fractional order PID (FO-PID) controller is designed for a seven-level ACHBMLI using a simplified small signal model. Simulation results show the FO-PID controller maintains the output voltage closer to the reference voltage and reduces harmonic distortion compared to a conventional PID controller. The FO-PID controller provides improved robustness over a conventional PID controller for the ACHBMLI.
ANALYSIS AND IMPLEMENTATION OF FPGA CONTROL OF ASYMMETRIC MULTILEVEL INVERTER...IJAMSE Journal
This paper presents an Asymmetric Multilevel Inverter (AMLI) with reduced number of switches for fuel
cells and suitable for high voltage and high power applications. Among the several types of multilevel
inverter, AMLI is a suitable choice to generate the higher number of output voltage levels with fewer
switches and sources. A novel hybrid modulation strategy based on Variable Amplitude Phase Opposition
and Disposition (VAPOD) is implemented using FPGA for AMLI which is powered by Proton Exchange
Membrane Fuel Cell (PEMFC). The operation of the proposed AMLI is verified with simulation and
experimental results.
Multilevel Inverters are getting popular and have become more attractive to researchers in the recent times for high power applications due to their better power quality and higher efficiency as compared to two level inverters. This research work presents a detailed comparative analysis of various multicarrier sinusoidal PWM schemes such as In Phase Disposition, Phase Opposition Disposition and Alternate Phase Opposite Disposition implemented on five level conventional and modified cascaded h-bridge inverters in MATLAB/SIMULINK software. Conventional five level topology uses eight switches and suffers from increased switching complexity while modified five level topology uses only five switches and is recommended to reduce switching complexity and switching losses. It also ensures less number of components, reduced size and overall cost of the system. The effect of modulation index (Ma) on the output harmonic contents in various PWM techniques is also analyzed.
This document summarizes a research paper that proposes and analyzes a multilevel line-commutated inverter topology for solar PV-based grid-connected inverters. The proposed topology uses a multi-winding transformer to provide multiple voltage levels and reduce harmonic distortion in the line current compared to a conventional square-wave inverter. A three-level implementation is modeled in Simulink and experimentally tested. Simulation and experimental results show the proposed topology reduces total harmonic distortion and improves power transfer characteristics compared to a conventional line-commutated inverter.
1) The document describes the analysis and simulation of an interleaved buck converter for automotive dual voltage systems. An interleaved six-phase buck converter is modeled and simulated in Simulink.
2) The interleaved topology provides benefits like reduced output ripple, smaller filter requirements, and improved reliability compared to a single phase buck converter.
3) Components like inductors, capacitors, and MOSFET switches are selected based on specifications such as a 1kW power rating and 71A output current. Simulation results are used to verify the effectiveness of the converter design.
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.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Experimental Validation of Shared Inverter Topology to Drive Multi AC-Loads IJECEIAES
Many reduced-switch-count (RSC) inverter topologies have been proposed in the literature. As the number of switches required to produce a set of voltages in RSC inverters are less than that in conventional inverter, as a result utilizing RSC inverters in a certain system reduces its size and cost. In this paper, a novel RSC shared inverter topology consisting of fifteen switches and capable of driving four three-phase AC-loads independently is proposed and experimentally verified. A carrier-based pulse width modulation (PWM) technique that employs the zero-sequence-signal injection principle is developed to drive the proposed inverter along with adequate DC voltage bus utilization between the shared loads for common frequency (CF) as well as different frequency (DF) modes. The structure and the principle of operation of the proposed inverter are introduced and intensively verified using simulation and field-programmable-gate-array (FPGA)-in-the-loop simulation under linear and nonlinear loads. Then, Inverter prototype was built and the proposed inverter has been verified experimentally. The experimental results verify the applicability of the proposed inverter and the employed PWM.
The conventional three-level inverter has been proposed to act as a recuperating converter in Traction Supply Substation. This converter is mainly used to feed back the regenerative braking energy to the grid. However, passive filter is desired to mitigate the current and voltage harmonics. Therefore, this paper investigates the possibility to use a seven-level Cascaded H-Bridge (CHB) converter as the recuperating converter without additional filtering. The proposed converter is modeled with MATLAB/Simulink simulation software. It is then simulated with two potential modulation schemes, namely Phase-Shifted PWM (PS-PWM) and Phase-Disposition PWM (PD-PWM). The quality of AC waveforms produced by these two modulation methods is compared and studied. The results show that PS-PWM technique is preferable for this application as it offered a clean AC current waveform with less than 5% harmonic distortion. However, a twenty-one-level CHB was predicted to comply with the 8% voltage harmonic requirement.
This document presents a single-stage isolated bi-directional converter topology using a high frequency AC link for charging and vehicle-to-grid applications of plug-in hybrid electric vehicles. The converter consists of two active bridges connected by a series resonant tank and high-frequency transformer. Steady-state analysis is presented to show how phase-shift modulation between the active bridges can control bidirectional power flow. Simulation results are provided to validate the analysis. The proposed converter has the advantages of minimal conversion stages, high switching frequency operation, and low switching losses.
A Novel Hybrid Negative Half Cycle Biased Modulation Scheme for Cascaded Mult...IJPEDS-IAES
This paper proposes a new Modified hybrid modulation scheme for cascaded multilevel inverter. The proposed method employs novel single carrier sinusoidal pulse width modulation with its negative cycle biased (HNHCBM) for reducing switching losses when compared to other sinusoidal modulation methods using a hybrid scheme. This scheme is a derivative of various single carrier sinusoidal pulse width modulation scheme and main advantages are reduced harmonics, enhanced output voltage, reduced power loss in the series cells and ease of implementation. The simulation results are analysed with matlab/simulink and compared with experimental results obtained using 5-level inverter and the results are summarized.
Common Mode Voltage reduction in Diode Clamped MLI using Alternative Phase Op...Mohd Esa
The main objective of this paper is to reduce the Common Mode Voltage (CMV) in the Diode Clamped Multilevel Inverter (DCMLI).Three phase Y-connected RL load is connected to DCMLI. The common mode voltage exists between neutral point of Y-connected load and system ground.CMV causes premature failure of bearings of induction motor and is essential to reduce. In this paper, Alternative Phase Opposition Disposition SPWM technique is used to reduce common mode voltage. Two level, five level, seven level and nine level DCMLI are compared in terms of THD and CMV.The effect of a passive LC filter on THD was studied. The simulation of circuit is carried out by using MATLAB/Simulink. Simulation result portrays reduction in THD and CMV by using APOD-SPWM controlled higher level Inverters.
INVESTIGATION OF COMMON MODE VOLTAGE IN 5-LEVEL DIODE CLAMPED MLI USING CARRI...Mohd Esa
The main aim of this paper is to investigate the Common Mode Voltage (CMV) and Total Harmonic Distortion (THD) in five level Diode Clamped Inverter using Carrier based SPWM techniques. The common mode voltage exists between neutral point of star connected load and system ground. Various Carrier based SPWM techniques used to analyze CMV and THD in this paper are Phase Disposition (PD) strategy, Phase Opposition Disposition (POD) strategy, Alternative Phase Opposition Disposition (APOD) strategy, Carrier Overlap Phase Disposition (COPD) Strategy, Carrier Overlap Phase Opposition Disposition (COPOD) strategy and Carrier Overlap Alternative Phase Opposition Disposition (COAPOD) strategy.RL load is connected to inverter circuit for analysis purpose and Simulation is performed using MATLAB/Simulink Software.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
PERFORMANCE INVESTIGATION OF ASYMMETRIC MULTILEVEL INVERTER WITH REDUCED SWIT...ecij
This paper investigates the performance of Asymmetric Multilevel Inverter (AMLI) with reduced number of switches for fuel cell applications. The proposed topology generates fifteen-level output with improved spectral quality of the output. Moreover, a novel hybrid modulation strategy based on Variable Amplitude Phase Opposition Disposition (VAPOD) technique is implemented. The proposed topology is powered by PEM fuel cell source which is modeled in MATLAB. The performance parameters such as Total Harmonic Distortion (THD), Weighted THD (WTHD), Harmonic Spread Factor (HSF) and Distortion Factor (DF) are computed to verify the performance of the proposed topology. Circuit simulation studies are carried out in MATLAB/SIMULINK software and the results are verified.
Implementation of High Throughput Radix-16 FFT ProcessorIJMER
The extension of radix-4 algorithm to radix-16 to achieve the high throughput of 2.59 giga-samples/s for WPAN’s.We are also reformulating radix-16 algorithm to achieve low-complexity and
low area cost and high performance. Radix-16 FFT is obtained by cascaded the radix -4 butterfly
units. It facilitates low-complexity realization of radix-16 butterfly operation and high operation speed
due to its optimized pipelined structure. Besides, a new three-stage multiplier for twiddle factor
multiplication is also proposed, which has lower area and power consumption than conventional
complex multipliers
Analysis and Performance evaluation of Traditional and Hierarchal Sensor NetworkIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
The Three Phases of the Anti-Christ PowerRobert Taylor
This document outlines keys to unlocking prophecies in the Bible. It discusses various symbols found in prophecies and their meanings, such as beasts representing ruling powers. It analyzes prophecies about a beast with seven heads and ten horns in Revelation 12-13 and 17. This beast represents the papacy, which ruled as a head/empire for 1260 years before being wounded but healing. Biblical knowledge of the antichrist power and its mark are said to be the last message before Jesus' return. Intellectual biblical knowledge is presented as the greatest reformer of Christianity.
Damping Of Composite Material Structures with Riveted JointsIJMER
Vibration and noise reduction are crucial in maintaining high performance level and
prolonging the useful life of machinery, automobiles, aerodynamic and spacecraft structures. It is
observed that damping in materials occur due to energy release due to micro-slips along frictional
interfaces and due to varying strain regions and interaction between the metals. But it was found
that the damping effect in metals is quite small that it can be neglected. Damping in metals is due to
the micro-slips along frictional interfaces. Composites, however, have better damping properties
than structural metals and cannot be neglected. Typically, the range of composite damping begins
where the best damped metal stops.In the present work, theoretical analysis was done on various
polymer matrix composite (glass fibre polyesters) with riveted joints by varying initial conditions.
Strain energy loss was calculated to calculate the damping in composites. Using FEA model, load
variation w.r.t time was observed and the strain energy loss calculated was utilised in finding the
material damping for Carbon fibre epoxy with riveted joints. Various simulations were performed in
ANSYS and these results were utilised to calculate the loss factor, Rayleigh‘s damping constants
and logarithmic decrement.
Hybrid Photovoltaic and thermoelectric systems more effectively converts solar energy into electrical energy. Two sources of energy are used one of the energy is solar,that converts radiant light into electrical energy and heat energy which will convert heat into electricity.Photovoltaic cells and thermoelectric modules are used to capture and convert the energy into electricity.Furthermore solar-thermoelectric hybrid system is environmental friendly and has no harmful emissions.Solar-thermoelectric hybrid system increases the overall reliability without sacrificing the quality of power generated.In this paper an overview of the previous research and development of technological advancement in the solar-thermoelectric hybrid systems is presented.
Greedy – based Heuristic for OSC problems in Wireless Sensor NetworksIJMER
This document summarizes an article about optimizing set coverage problems in wireless sensor networks. It discusses the following key points:
1) Wireless sensor networks aim to maximize network lifetime by scheduling sensors to alternate between active and sleep modes or adjusting transmission ranges. The optimize set coverage (OSC) problem aims to find a maximum number of set covers where each active sensor is connected to the base station.
2) The OSC problem is proved to be NP-complete. Integer programming and linear programming models are proposed to formulate the OSC problem.
3) Greedy-based heuristics are presented for solving the OSC problem in a centralized and distributed manner. Simulations are used to validate the performance of
This document discusses the development of a fighting game that uses optical touch sensing technology. It begins by providing background on the evolution of gaming from arcades to smartphones. It then proposes that an optical touch sensing method could be used to create fighting games on large screens in a cost-effective way. The document describes a sample fighting game implemented using this touch method, where players compete by pressing buttons rapidly or playing rock-paper-scissors to gain advantages. It concludes that optical touch sensing could reduce production costs for games and allow children to play more easily and comfortably on large interactive surfaces.
Performance Analysis of Routing Metrics for Wireless Sensor NetworksIJMER
This document summarizes and compares various routing metrics that have been proposed for wireless sensor networks. It categorizes the routing metrics into five groups: topology based, signal strength based, active probing based, mobility aware, and energy aware. Topology based metrics like hop count consider only connectivity information without additional measurements. Signal strength and active probing based metrics directly measure link quality through signal strength or probe packets. The document provides detailed descriptions of several popular routing metrics, such as expected transmission time (ETT), medium time metric (MTM), round-trip time (RTT), and packet pair delay. It analyzes the characteristics of different routing metrics and compares their performance.
Fuzzy soft set is one of the recent topics developed for dealing with the uncertainties present
in most of our real life situations. The parameterization tool of soft set theory enhances the flexibility of
its application. In this paper, we have studied membership grade, power set,
-cut set , strong fuzzy
-
cut set ,some standard operation fuzzy soft set, degree of subset hood and proposed some results with
examples.
The document discusses the pure everlasting gospel as presented in Revelation 14. It explains that the gospel has been contaminated over time with unbiblical teachings added after the death of Jesus. The three angels' messages of Revelation 14 will restore the pure gospel by removing these contaminations. Their message will call people back to worshipping God as the Creator and keeping all of His commandments, including the seventh-day Sabbath. This restored gospel will empower the final outpouring of the Holy Spirit.
Detection of Duplicate Address in Mobile Adhoc Networks for On Demand Routing...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
The author conducted a 30-day challenge where she wrote one blog post and one article per day to increase traffic to her site. Some key lessons learned were that consistent action produces results, having specific goals is important, and researching keywords can lead to increased traffic and sales leads over time. The challenge increased her site traffic by 68% over the month. She plans to implement improvements like setting a writing schedule, focusing topics, and better promotion for future challenges.
Bearing Life Improvement of Centrifugal Blowers by Vibration AnalysisIJMER
This document discusses vibration analysis of centrifugal blowers to improve bearing life. It analyzes blower structural issues and causes of vibration like design defects, manufacturing defects, and operational stresses. Vibration data is collected from various blower locations and analyzed using spectral plots. Corrective actions like balancing, alignment, and modifying accessories like the plumber block are discussed to prevent bearing failure. Equations for calculating ball pass frequencies, bearing life, heat generation, grease quantity, and friction coefficients are also provided. The analysis indicates excessive vibration develops due to material buildup changing balance conditions. Periodic vibration monitoring and corrective maintenance actions can extend equipment life.
The document discusses the need to integrate disaster management into engineering curriculum. It argues that engineers will be better prepared to handle disasters if concepts of disaster management are incorporated across engineering subjects rather than as an elective. Integrating these concepts will give students a holistic understanding and help them apply theoretical knowledge to practical problems. The document recommends using problem-based and interdisciplinary learning to motivate students and help them develop skills like teamwork and communication that are important for disaster response.
Scan-Based Delay Measurement Technique Using Signature RegistersIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
The magazine uses a bright color scheme and prominent masthead to attract older, loyal viewers interested in weekly television programs. It encourages brand loyalty through its website listed in the masthead and provides value with multiple television program features and images. The largest headline teases a mystery to engage readers in learning more about the main story.
This document provides examples of proper Associated Press (AP) style guidelines for punctuation, capitalization, abbreviations, numbers, addresses, dates, directions, and other elements in writing. It compares the correct AP style versus incorrect or non-standard styles for over 50 different examples. The purpose is to illustrate the AP style rules for writing news stories and journalistic pieces.
Development of a Smart Mechatronic Tracking System to Enhance Solar Cell Pane...IJMER
Two degree of freedom Mechatronic solar tracking system was developed in the present study
to improve the performance of photovoltaic cell panels. The present tracking control algorithm was
applied on a small prototype, simulating a solar cells panel tracking system, designed and constructed in
this work. The Mechatronic tracking hardware section consists mainly of a commercial arduino microcontroller
with built in, two servo motor drivers, data input/output, and micro processor modules. Other
components of the tracking hardware are, servo motors actuators and four LDR light intensity sensors. A
feedback control soft ware program, designed and constructed in the present work, enables the solar
tracker to automatically compensate for the sun location’s change to enhance the PV cells efficiency. The
LDR sensors are employed to continuously detect the sun rays intensity at four, light exposed isolated
positions, representing up-right, up-left, down-right, and down-left sides of the solar panel. LDRs data is
hence sent to the control software. The data is used to decide proper actuation actions and send them to
the servomotors to redirect the PV cells panel perpendicular to incident sun rays. Sensors and actuation
signals are exchanged via the in/out data module of the Arduino package. Results of the present
experimental work show that using the present tracking system increases the PV cell out power by about
38% compared with that of a fixed collector
Seemas Academy is an ISO 9001-2008 registered company based in Solapur, Maharashtra, India that was established in 2003 to provide brain development and math/science training courses based on Japanese abacus and Indian Vedic math concepts. The company aims to explore human talent and serve national advancement through imparting internationally standardized brain training. Courses offered include midbrain activation, speed reading, abacus, mental arithmetic, and Vedic mathematics for both children and adults.
Harmonic comparisons of various pwm techniques... A reportSaquib Maqsood
Abstract: Cascaded inverters are ideal for connecting renewable energy sources with an AC grid, because of the need for separate dc sources, which is the case in applications such as photovoltaic or fuel cells. The inverter could be controlled to either regulate the power factor of the current drawn from the source or the bus voltage of the electrical system where the inverter was connected. The modulation techniques are crucial in operating any inverter at desired conditions. In this work different PWM techniques are implemented for five level cascaded multilevel inverter and THD variation is analyzed.
Analysis and Implementation of Unipolar PWM Strategies for Three Phase Cascad...IJAAS Team
This paper presents unipolar pulse width modulation technique with sinusoidal sampling pulse width modulation are analyzed for three-phase five-level, seven-level, nine-level and eleven-level cascaded multi-level inverter. The unipolar PWM method offers a good opportunity for the realization of the Three-phase inverter control, it is better to use the unipolar PWM method with single carrier wave compared to two reference waves. In such case the motor harmonic losses will be considerably lower.The necessary calculations for generation of unipolar pulse width modulation strategies have presented in detail. The unipolar SPWM voltage switching scheme is selected in this paper because this method offers the advantages of effectively doubling the switching frequency of the inverter voltage. The cascaded multi level inverter fed induction motor is simulated and compared the total harmonic distroction for all level (five-level, seven-level, nine-level and elevel-level)of the inverter. Theoretical investigations were confirmed by the digital simulations using MATLAB/SIMULINK software.
This paper studies the Asymmetric cascaded three phase multilevel inverter developed with hybrid modulation technique applied for an industrial application. The aim of this paper to reduce the Total harmonics distortion in the cascaded multi level inverter by introducing the new concept to develop the three phase CMLI. This inverter has two segments, one segment has H-bridge inverter and another segment has sequential arrangement of power semi conductor switches with asymmetrical voltage source in the ratio of 1:2. Similarly develop the segments for other phases. This new topology is called as Hybrid MLI. This hybrid MLI is used to reduce the no of semiconductor device requirement and the Total harmonics distortion. The inverter is controlled by Phase disposition (PD) and alternative phase opposition disposition PWM technique (APOD). This control technique is used to minimize the current harmonic and increase the system performance. The circuit is simulated using Matlab circuit and its performance is compared using PD and APOD PWM techniques and verified with simulation results.
Simulation and dSPACE Based Implementation of Various PWM Strategies for a Ne...IJPEDS-IAES
Depending on the number of levels in output voltage, inverters can be
divided into two categories: two level inverter and Multi Level Inverters
(MLIs). An inverter topology for high voltage and high power applications
that seems to be gaining interest is the MLI. In high power and high voltage
applications, the two level inverters have some limitations in operating at
high frequency mainly due to switching losses and constraints of device
rating.In this paper, a three phase H + type FCMLI (Flying Capacitor MLI)
using sinusoidal reference, third harmonic injection reference, 60 degree
reference and stepped wave reference are initially developed using
SIMULINK and then implemented in real time environment using dSPACE.
In H-type FCMLI with R-load it is inferred that bipolar COPWM-C
provides output with relatively low distortion for 60 degree reference
and bipolar COPWM-C strategy is found to perform better since it
provides relatively higher fundamental RMS output voltage for THI
reference. The five level output voltages of the chosen MLIs obtained using
the MATLAB and dSPACE based PWM (Pulse Width Modulation)
strategies and the corresponding %THD (Total Harmonic Distortion), VRMS
(fundamental), CF (Crest Factor) and FF (Form Factor) are presented and
analyzed.
Performance Evaluation of a Three Phase Nine Level Inverter with Reduced Sw...Scientific Review SR
This paper presents a three phase nine level cascaded H-bridge (CHB) multilevel inverter with RL load. A sinusoidal and trapezoidal PWM method is used to achieve minimum total harmonics distortion (THD) in the output current of multilevel inverters. The analysis of the output current harmonics is carried out and compared with the seven level conventional cascaded H-bridge inverters. The proposed inverter is verified through
simulation and the simulation results are compared with the conventional multilevel inverter. From the result the
proposed inverter offers much less total harmonic distortion
The aim of this paper is to determine the Total harmonic distortion (THD) of three phase three level flying capacitor inverter fed star connected R-L load. The modulation Techniques used is Phase Disposition Sinusoidal pulse width modulation (PD-SPWM) and Phase Opposition Disposition Sinusoidal pulse width modulation (POD-SPWM).The Modulation index is varied to analyze its effect on Current THD and Voltage THD.This paper also presents the comparison of PD-SPWM and POD-SPWM controlled Flying capacitor Inverter in terms of THD. The simulation result shows that PD-SPWM has better performance when compared to POD-SPWM. The simulation of circuit is done by using MATLAB/Simulink.
Harmonic Analysis of Three level Flying Capacitor InverterMohd Esa
The aim of this paper is to determine the Total harmonic distortion (THD) of three phase three level flying capacitor inverter fed star connected R-L load. The modulation Techniques used is Phase Disposition Sinusoidal pulse width modulation (PD-SPWM) and Phase Opposition Disposition Sinusoidal pulse width modulation (POD-SPWM).The Modulation index is varied to analyze its effect on Current THD and Voltage THD.This paper also presents the comparison of PD-SPWM and POD-SPWM controlled Flying capacitor Inverter in terms of THD. The simulation result shows that PD-SPWM has better performance when compared to POD-SPWM. The simulation of circuit is done by using MATLAB/Simulink.
Optimized Hybrid Phase Disposition PWM Control Method for Multilevel InverterIDES Editor
This paper presents a new variation of hybrid
phase disposition pulse width modulation technique suitable
for cascaded multilevel inverter. A hybrid PDPWM is
developed based on low frequency PWM and high
frequency Sinusoidal PWM. An optimized sequential
switching scheme introduced in this proposed method to
equalize electro static and electro magnetic stress among the
power devices. It is confirmed that the proposed technique
offers significantly lower switching losses and switching
transitions. Furthermore, the proposed hybrid PDPWM
offers better harmonic performance compared to its
conventional PWM counterpart. Simulation results are
included in this paper in order to confirm the effectiveness
of the proposed technique.
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.
Five Level Hybrid Cascaded Multilevel Inverter Harmonic Reduced in PWM Switch...ijsrd.com
The power electronics device which converts DC power to AC power at required output voltage and frequency level is known as a inverter. This paper describes a harmonics reduced in a hybrid cascaded multilevel inverter circuit with pulse width modulation (PWM) scheme. These scheme pulse width modulations in modified method are uses reduce switching device. These methods are a conventional inverter and hybrid inverter combine form. This topology used the combined form of a new five level hybrid cascaded multilevel inverter. The multilevel carrier based pulse width modulation methods are used in this topology five level output voltage wave forms is shown in FFT window MATLABE/SIMULINK is used to simulate the inverter circuit operation and control signals.
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.
CMV analysis of 5-level Cascaded H-Bridge MLI with equal and unequal DC sourc...Mohd Esa
This paper, investigates the Common Mode Voltage (CMV)between neutral point of the star connected RL load and system ground.CMV also known as zero sequence voltage results in adverse effects like bearing currents, shaft voltages and electromagnetic interference.CMV also causes premature failure of bearings of induction motor and is necessary to reduce. In this paper, Variable Frequency Sinusoidal Pulse Width Modulation (VFSPWM) techniques are used to investigate CMV in Cascaded H-Bridge Multilevel Inverter (CHB-MLI). Comparison of 5-level CHB-MLI with equal and unequal DC sources in terms of CMV is also presented. Simulation of circuit is carried out in MATLAB environment.
CMV analysis of 5 level Cascaded H Bridge MLI with equal and unequal DC sourc...MOHD ABDUL MUQEEM NAWAZ
This paper, investigates the Common Mode Voltage (CMV)between neutral point of the star connected RL load and system ground.CMV also known as zero sequence voltage results in adverse effects like bearing currents, shaft voltages and electromagnetic interference.CMV also causes premature failure of bearings of induction motor and is necessary to reduce. In this paper, Variable Frequency Sinusoidal Pulse Width Modulation (VFSPWM) techniques are used to investigate CMV in Cascaded H-Bridge Multilevel Inverter (CHB-MLI). Comparison of 5-level CHB-MLI with equal and unequal DC sources in terms of CMV is also presented. Simulation of circuit is carried out in MATLAB environment.
COMPREHENSIVE ANALYSIS AND SIMULATION OF MULTILEVEL POWER CONVERTERS TO CURTA...ecij
Present day industrial applications require higher power apparatus for power conversion. At medium voltage grid, to connect only one power semiconductor switch directly is a not practically successful concept. To overcome this multilevel power converter structure has been introduced and studied as an alternative in high power and medium voltage applications. Renewable energy sources like photovoltaic, wind, fuel cells can be conveniently interfaced to a multilevel converter system for high power applications. In this study it is discussed in detail for different levels of the multilevel converters using pulse width
modulation technique (PWM) the harmonics contents decreases gradually. The simulated results are presented and compared thereafter. Total harmonic distortion decreases as the number of levels increased are tabulated accordingly. All the simulation results are carried out under MATLAB/Simulink environment.
COMPREHENSIVE ANALYSIS AND SIMULATION OF MULTILEVEL POWER CONVERTERS TO CURTA...ecij
Present day industrial applications require higher power apparatus for power conversion. At medium
voltage grid, to connect only one power semiconductor switch directly is a not practically successful
concept. To overcome this multilevel power converter structure has been introduced and studied as an
alternative in high power and medium voltage applications. Renewable energy sources like photovoltaic,
wind, fuel cells can be conveniently interfaced to a multilevel converter system for high power applications.
In this study it is discussed in detail for different levels of the multilevel converters using pulse width
modulation technique (PWM) the harmonics contents decreases gradually. The simulated results are
presented and compared thereafter. Total harmonic distortion decreases as the number of levels increased
are tabulated accordingly. All the simulation results are carried out under MATLAB/Simulink environment.
CHB VSI Based Shunt Active Power Filter for PV Connected DSTATCOM in Three Ph...ijsrd.com
This paper presents a compensating system for the harmonic currents, the reactive power and source neutral conductor current in three-phase four-wire distribution system by using a five-level cascaded H-bridge voltage source inverter (CHB-VSI) based shunt active power filter (SAPF). A controller based on the d-q-0 theory (synchronous reference frame) and in-phase disposition (IPD) modulation technique is introduced for the SAPF. The distribution network which supplies mixed non-linear loads and employing CHB-VSI based SAPF is simulated by MATLAB/SIMULINK software. The performance of SAPF is analyzed by using the proposed control technique on the total harmonic distortion of source current, power factor and reactive power. Besides, it is illustrated by extensive simulation results, the effectiveness of five-level SAPF on source neutral conductor current.
Investigation of TTMC-SVPWM Strategies for Diode Clamped and Cascaded H-bridg...ijeei-iaes
This paper presents a concept of two types multilevel inverters such as diode clamped and cascaded H-bridge for harmonic reduction on high power applications. Normally, multilevel inverters can be used to reduce the harmonic problems in electrical distribution systems. This paer focused on the performance and analysis of a three phase seven level inverter including diode clamped and cascaded H-bridge based on new tripizodal triangular space vector PWM technique approaches. TTMC based modified Space vector Pulse width modulation technique so called tripizodal triangular Space vector Pulse width modulation (TTMC-SVPWM) technique. In this paper the reference sine wave generated as in case of conventional off set injected SVPWM technique. It is observed that the TTMC-Space vector pulse width modulation ensures excellent, close to optimized pulse distribution results and THD is compared to seven level, diode clamped and cascaded multi level inverters. Theoretical investigations were confirmed by the digital simulations using MATLAB/SIMULINK software.
This document provides an overview of various pulse width modulation techniques for voltage source inverters, including naturally sampled PWM, regular sampled PWM, delta modulation, delta sigma modulation, space vector modulation, and hysteresis PWM. It describes the basic concepts and operating principles of each technique, and compares them in terms of performance metrics like harmonic distortion and switching losses. Space vector modulation techniques are ranked as providing the best performance in terms of minimizing harmonics, followed by regular sampled PWM and sine-triangle modulation.
Simulation and study of multilevel inverter (report)Arpit Kurel
The document discusses the simulation and study of a multilevel inverter. It begins with an abstract that outlines that multilevel inverters are used to convert DC power to AC power at required voltage and frequency levels for applications like motor drives and grid connections. It then discusses different multilevel inverter topologies like diode clamped, flying capacitor, and cascaded H-bridge. For this project, a three phase five level inverter is simulated using sinusoidal PWM technique in MATLAB/Simulink. The topology used is a cascaded H-bridge inverter with separate DC sources. The multilevel inverter reduces harmonic contents in the output waveform compared to a three level inverter.
A Study on Translucent Concrete Product and Its Properties by Using Optical F...IJMER
- Translucent concrete is a concrete based material with light-transferring properties,
obtained due to embedded light optical elements like Optical fibers used in concrete. Light is conducted
through the concrete from one end to the other. This results into a certain light pattern on the other
surface, depending on the fiber structure. Optical fibers transmit light so effectively that there is
virtually no loss of light conducted through the fibers. This paper deals with the modeling of such
translucent or transparent concrete blocks and panel and their usage and also the advantages it brings
in the field. The main purpose is to use sunlight as a light source to reduce the power consumption of
illumination and to use the optical fiber to sense the stress of structures and also use this concrete as an
architectural purpose of the building
Developing Cost Effective Automation for Cotton Seed DelintingIJMER
A low cost automation system for removal of lint from cottonseed is to be designed and
developed. The setup consists of stainless steel drum with stirrer in which cottonseeds having lint is mixed
with concentrated sulphuric acid. So lint will get burn. This lint free cottonseed treated with lime water to
neutralize acidic nature. After water washing this cottonseeds are used for agriculter purpose
Study & Testing Of Bio-Composite Material Based On Munja FibreIJMER
The incorporation of natural fibres such as munja fiber composites has gained
increasing applications both in many areas of Engineering and Technology. The aim of this study is to
evaluate mechanical properties such as flexural and tensile properties of reinforced epoxy composites.
This is mainly due to their applicable benefits as they are light weight and offer low cost compared to
synthetic fibre composites. Munja fibres recently have been a substitute material in many weight-critical
applications in areas such as aerospace, automotive and other high demanding industrial sectors. In
this study, natural munja fibre composites and munja/fibreglass hybrid composites were fabricated by a
combination of hand lay-up and cold-press methods. A new variety in munja fibre is the present work
the main aim of the work is to extract the neat fibre and is characterized for its flexural characteristics.
The composites are fabricated by reinforcing untreated and treated fibre and are tested for their
mechanical, properties strictly as per ASTM procedures.
Hybrid Engine (Stirling Engine + IC Engine + Electric Motor)IJMER
Hybrid engine is a combination of Stirling engine, IC engine and Electric motor. All these 3 are
connected together to a single shaft. The power source of the Stirling engine will be a Solar Panel. The aim of
this is to run the automobile using a Hybrid engine
Fabrication & Characterization of Bio Composite Materials Based On Sunnhemp F...IJMER
This document summarizes research on the fabrication and characterization of bio-composite materials using sunnhemp fibre. The document discusses how sunnhemp fibre was used to reinforce an epoxy matrix through hand lay-up methods. Various mechanical properties of the bio-composites were tested, including tensile, flexural, and impact properties. The results of the mechanical tests on the bio-composite specimens are presented. Potential applications of the sunnhemp fibre bio-composites are also suggested, such as in fall ceilings, partitions, packaging, automotive interiors, and toys.
Geochemistry and Genesis of Kammatturu Iron Ores of Devagiri Formation, Sandu...IJMER
The Greenstone belts of Karnataka are enriched in BIFs in Dharwar craton, where Iron
formations are confined to the basin shelf, clearly separated from the deeper-water iron formation that
accumulated at the basin margin and flanking the marine basin. Geochemical data procured in terms of
major, trace and REE are plotted in various diagrams to interpret the genesis of BIFs. Al2O3, Fe2O3 (T),
TiO2, CaO, and SiO2 abundances and ratios show a wide variation. Ni, Co, Zr, Sc, V, Rb, Sr, U, Th,
ΣREE, La, Ce and Eu anomalies and their binary relationships indicate that wherever the terrigenous
component has increased, the concentration of elements of felsic such as Zr and Hf has gone up. Elevated
concentrations of Ni, Co and Sc are contributed by chlorite and other components characteristic of basic
volcanic debris. The data suggest that these formations were generated by chemical and clastic
sedimentary processes on a shallow shelf. During transgression, chemical precipitation took place at the
sediment-water interface, whereas at the time of regression. Iron ore formed with sedimentary structures
and textures in Kammatturu area, in a setting where the water column was oxygenated.
Experimental Investigation on Characteristic Study of the Carbon Steel C45 in...IJMER
In this paper, the mechanical characteristics of C45 medium carbon steel are investigated
under various working conditions. The main characteristic to be studied on this paper is impact toughness
of the material with different configurations and the experiment were carried out on charpy impact testing
equipment. This study reveals the ability of the material to absorb energy up to failure for various
specimen configurations under different heat treated conditions and the corresponding results were
compared with the analysis outcome
Non linear analysis of Robot Gun Support Structure using Equivalent Dynamic A...IJMER
Robot guns are being increasingly employed in automotive manufacturing to replace
risky jobs and also to increase productivity. Using a single robot for a single operation proves to be
expensive. Hence for cost optimization, multiple guns are mounted on a single robot and multiple
operations are performed. Robot Gun structure is an efficient way in which multiple welds can be done
simultaneously. However mounting several weld guns on a single structure induces a variety of
dynamic loads, especially during movement of the robot arm as it maneuvers to reach the weld
locations. The primary idea employed in this paper, is to model those dynamic loads as equivalent G
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Discrete Model of Two Predators competing for One Prey
Ag2418141818
1. International Journal of Modern Engineering Research (IJMER)
www.ijmer.com Vol.2, Issue.4, July-Aug. 2012 pp-1814-1818 ISSN: 2249-6645
A New Three Phase Seven Level Asymmetrical Inverter
with Hybrid Carrier and Third Harmonic Reference
Johnson Uthayakumar R.*, Natarajan S.P.**, Padmathilagam.V.***
*Department of Electronics and Instrumentation Engineering, Annamalai University, India
** Department of Electronics and Instrumentation Engineering, Annamalai University, India
*** Department of Electrical and Electronics Engineering, Annamalai University, India
ABSTRACT: Carrier based techniques have been used conventional sinusoidal reference signal and an inverted sine
widely for switching of multilevel inverters due to their carrier to produce better spectral quality and a higher
simplicity, flexibility and reduced computational fundamental component compared to the conventional
requirements compared to Space Vector Modulation (SVM). Sinusoidal PWM (SPWM) without any pulse dropping. A
A novel carrier based Pulse Width Modulation (PWM) survey of topologies, controls and applications of MLIs has
technique for three phase Asymmetrical Multi Level Inverter been carried out by Rodriguez et al [6]. The common
(AMLI) with Third Harmonic Injection (THI) reference is topology is the cascaded inverter shown in Fig.1 for three
proposed in this paper. The technique is based on the phase structure. The three multilevel modulation methods
combination of the Control Freedom Degrees (CFD). The most discussed in the literature include multilevel carrier-
combination of inverted sine carrier and triangular carrier based PWM, multilevel space-vector PWM and selective
is used as hybrid carrier in order to produce pulses for the harmonic elimination [6]. Analysis of multicarrier PWM
power switches used in the proposed seven level three phase methods for a single phase five level inverter was proposed
cascaded inverter. This paper investigates the potentials of by Calais Borle and Agelidis [7]. A novel clew for the
hybrid carrier based cascaded multilevel inverter in the research on carrier based PWM methods for multilevel
development of medium power AC power supplies with inverters is proposed by Wu et al [8] based on the concept
specific emphasis on Power Conditioning Systems (PCS) for of combination of the Control Freedom Degrees (CFD). Sun
alternate sources of energy. The performance of chosen [9] have presented a new asymmetrical multilevel inverter
inverter is evaluvated based on MATLAB/ SIMULINK topology. The new topology can improve the number of
simulation. The performance indices used are Total output voltage levels greatly using a bidirectional auxiliary
Harmonic Distortion (THD), RMS value of output voltage switch. Further they have proposed multicarrier PWM
and DC bus utilization. It is observed that Carrir over method for the asymmetrical inverter [9]. Taleb et al [10]
lapping PWM provides better DC bus utilization and Phase have proposed a neural implementation of a Harmonic
opposition Disposition (POD) technique creates less Elimination Strategy (HES) to control a Uniform Step
distortion for ma=0.7-1 Asymmetrical Multilevel Inverter (USAMI). Mihalache [11]
has proposed an asymmetrical PWM modulation technique
which is known to offer lower harmonic content as
Keywords: APOD, COPWM, PD, POD, ISPWM
compared to the symmetrical modulation. Nami et al [12]
have optimized asymmetrical arrangement compared with a
I. INTRODUCTION conventional four level inverter and found that it exhibits
In recent years, multi-level Voltage Source Inverters (VSIs) lesser switching losses and lesser harmonics. In some
are widely used as static power converter for high-power application with different DC input sources such as electric
applications. MLIs can operate at both fundamental vehicles, a modular H-bridge asymmetrical inverter can be
switching frequency and high switching frequency PWM. used to drive a traction motor from a set of solar cells or fuel
The topologies of MLIs are classified into three types: the cells. A seven level output voltage is achieved with two
flying capacitor inverter, the diode clamped inverter and the bridges in asymmetrical inverter whereas only five level
modular H-bridge inverter. Seyezhai and Mathur [1] have output voltage will be achieved with three bridges in case of
described a technique that combines the advantage of conventional cascaded MLI. In AMLI with lesser number
inverted rectified sine wave and variable frequency carriers switches more voltage levels can be achieved. Fig.1. shows
for a seven level inverter for balancing the switch utilization the chosen asymmetrical three phase inverter. Each cell has
and have also stated that the switching losses for the chosen two pairs of complementory switches S1 and S3 and S2 and
modulation scheme is very less. Chandra and Kumar in [2] S4. There are six cells used in the three phase inverter each
presented an automatic switching pattern generation for leg containing two cells each. Since the carrier based
multilevel cascaded H-Bridge inverters with equal DC method have good CFD, this paper focusses on the hybrid
voltage sources based on the Space Vector Pulse Width carrier arrangement using triangular carrier in the positive
Modulation (SVPWM) technique. Seyezhai and Mathur side and inverted sine carrier waveform in the negative side
[3,4] have done a comparative evaluation between hybrid with Phase Disposition (PD), Phase Opposition Disposition
modulation strategy and the conventional Phase Disposition (POD), Alternate Phase Opposition Disposition (APOD),
(PD) PWM method in terms of output voltage quality, Carrier Overlapping (CO) and Inverted Sine (IS) strategies.
power circuitry complexity, Distortion Factor (DF) and Fig.2. shows a sample SIMULINK model developed for
THD. Jeevananthan et al [5] have proposed an Inverted PWM strategy of a three phase inverter.
Sine Carrier PWM (ISCPWM) method which used the
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Fig.3.Carrier arrangements for PDPWM hybrid carrier
strategy
II (b) PODPWM hybrid carrier
This technique employs (m-1) carriers which are all
Fig.1. A three phase asymmetrical cascaded seven level in phase above and below the zero reference. In seven level
inverter converters all the six carrier waves above zero reference are
phase shifted by 180 degrees with the ones below zero
reference. The PODPWM is explained in the Fig.4 in which
Phase-A
all the carriers above the zero reference are in phase and
Pulses carriers below the zero reference are also in phase but are
phase shifted by 180 degree with respect to that above zero
reference. Fig.4 illustrates the POD PWM hybrid carrier and
THI reference arrangements for a phase leg of a three phase
Phase-B seven level cascaded structure with ma = 0.8.
Pulses
Phase-C
Pulses
Fig.2.A sample SIMULINK model developed for PWM
strategy of a three phase inverter
II. HYBRID CARRIER BASED BIPOLAR Fig.4. Carrier arrangements for PODPWM hybrid carrier
MODULATION SCHEMES WITH THI strategy
REFERENCE
The maximum modulation index of a three phase II (c) APODPWM hybrid carrier strategy
inverter can be increased by including a common mode third This technique requires each of the m-l carrier waveforms
harmonic term into the target reference waveform of each for an m-level phase waveform to be phase displaced from
phase leg. In this method, the modulation index ma can be each other by 180 degrees alternatively. In The APOD
increased beyond ma=1.0 without moving into over hybrid carrier and THI reference arrangements for a phase
modulation. leg of a three phase seven level cascaded structure with
ma=0.8 are illustrated in Fig.5.
II (a) PDPWM hybrid carrier strategy
This technique employs (m-l) carriers which are all in phase
for a m level inverter. In seven level converter all the six
carrier waves are in phase with each other across all the
bands as described in Fig.3 for a phase leg of a seven level
cascaded structure with ma = 0.8.
Fig.5. Carrier arrangements for APODPWM hybrid carrier
strategy
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II (d) COPWM hybrid carrier input DC sources are asymmetrical i.e one of the cascaded
For an m-level inverter using carrier overlapping technique, bridge is fed with Vdc/2 and other by Vdc. Figs.8-12 illustrate
(m-1) carriers with the same frequency (fc) and same peak- the output voltages of three phase asymmetrical cascaded
to-peak amplitude (Ac) are disposed such that the bands they seven level multilevel inverter for ma=0.8 only. The Root
occupy overlap each other; the overlapping vertical distance Mean Square (RMS) value, Total Harmonic Distortion
between each carrier is 0.5Ac. The reference waveform has (THD) and Form Factor (FF) of output voltage are evaluated
amplitude of Am and frequency of fm and it is centered in the with suitable formula and for various hybrid modulation
middle of the carrier signals. schemes such as PD, POD, APOD, COPWM, VFPWM
statergies for various ma (0.7-1) as in Tables I-III. Fig.13-18
Fig.6 shows the COPWM hybrid carrier and THI reference display the frequency spectra and %THD for chosen
arrangements for a phase leg of a three phase seven level strategies. It is found that the DC bus utilisation of the three
cascaded structure with ma =0.8. phase seven level cascaded multilevel inverter is much
better in case of COPWM as in Table II. POD technique is
formed to create less distortion. It is seen that 3 rd,37th, 39th
harmonics are dominant in PD and POD PWM where as
3rd,27th,31st,33rd,35th,37th,39th harmonics are dominant in
APOD PWM. VFPWM creates only 3rd,harmonic dominant
energy where as in COPWM 3rd,35th,37th,39th harmonics are
dominant.The following parameter values are used
simulation: Vdc1 =100V, Vdc2 =50V Ac=1, mf=40 and
R(load) = 100 ohms for each phase.
Fig.6. Carrier arrangements for COPWM hybrid carrier
strategy
II (e) VFPWM hybrid carrier strategy
Fig.7 illustrates the VFPWM hybrid carrier and THI
reference arrangements for a phase leg of a seven level three
phase cascaded structure with ma = 0.8.
Fig.8.Output voltage of hybrid carrier THI-PDPWM
strategy
Fig.7. Carrier arrangements for VFPWM hybrid carrier
strategy
The frequency modulation index
Fig.9.Output voltage of hybrid carrier THI-PODPWM
m f = fc/fm strategy
The amplitude modulation index
ma = 2Am/ (m-1) Ac
where
fc – Frequency of the carrier signal
fm – Frequency of the reference signal
Am –Amplitude of the reference signal
Ac – Amplitude of the carrier signal
ma =Am / (m / 4)* Ac (COPWM)
III. SIMULATION RESULTS
Simulation results have been obtained by using Fig.10.Output voltage of hybrid carrier THI-APODPWM
MATLAB/SIMULINK power system toolbox software. The strategy
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Fig.11.Output voltage of hybrid carrier THI-COPWM
strategy Fig.15. FFT spectrum for hybrid APODPWM strategy for
ma=0.8 and mf =40 with THI reference
Fig.12.Output voltage of hybrid carrier THI-VFPWM
strategy Fig.16. FFT spectrum for hybrid COPWM strategy for
ma=0.8 and mf =40 with THI reference
Fig.13. FFT spectrum for hybrid PDPWM strategy for
ma=0.8 mf =40 with THI reference
Fig.17. FFT spectrum for hybrid VFPWM strategy for
ma=0.8 mf =40 with THI reference
Fig.14. FFT spectrum for hybrid PODPWM strategy for
ma=0.8 and mf =40 with THI reference
Fig.18.%THD Vs ma for all strategies.
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Table-I REFERENCES
%THD of output voltage of AMLI for various values of ma [1] R.Seyezhai, B.L.Mathur “Implementation and Control
ma PD POD APOD VF CO of Variable Frequency ISPWM Technique for an
Asymmetric Multilevel Inverter” European Journal of
1 19.69 19.6 19.9 19.67 22.72
Scientific Research ISSN 1450-216X Vol.39 No.4
0.95 21.3 21.48 20.89 21.46 24.07 (2010), pp.558-568
0.9 23.07 22.95 22.75 23.1 25.38 [2] K.Chandra, J.Kumar, A Simple and Generalized Space
Vector PWM Control of Cascaded H-Bridge
0.85 24.82 24.84 24.49 24.72 26.78
Multilevel Inverters. IEEE Trans. on Industrial
0.8 25.88 27.37 27.15 26.05 29.59 Electronics, (2006).
0.75 29.29 29.27 29.4 29.21 30.67 [3] R. Seyezhai "Investigation of Performance Parameters
For Asymmetric Multilevel Inverter" Using Hybrid
0.7 32.9 32.27 32.8 32.86 33.98
Modulation Technique. International Journal of
Engineering Science and Technology (IJEST) (2011).,
Table-II 3(12), 8430-8443.
RMS(Fundamental) value of output voltage of AMLI for [4] R. Seyezhai, B.L.Mathur “Hybrid Multilevel Inverter
different PWM strategies and various values of ma using ISPWM Technique for Fuel Cell Applications”
ma PD POD APOD VF CO International Journal of Computer Applications (0975
1 160.2 160.1 160.1 160 168.6 – 8887) Volume 9– No.1, November 2010
[5] S.Jeevananthan, R.Nandhakumar and
0.95 154 153.6 153.9 153.6 164 P.Dananjayan,“Inverted Sine Carrier for Fundamental
0.9 147.4 147.6 147.7 147.2 158.1 Fortification in PWM Inverters and FPGA Based
0.85 140.3 140.3 140.5 140.4 153.8 Implementations”, Serbian Journal of Electrical
Engineering, Vol. 4, No. 2(2007), pp. 171-187.
0.8 133.1 133.1 133 133 147.9 [6] J.Rodriguez, J.S.Lai, and F.Z.Peng,“Multilevel
0.75 125.2 125.1 125.2 125.4 141.4 Inverter: A Survey of Topologies, Controls and
0.7 116.4 116 116.4 116.3 133.8 Applications”, IEEE Trans. on Industrial Electronics,
Vol. 49 (2000), No. 4 pp. 724-738 .
[7] Calais, M., Borle, L. J. and Agelidis, V. G.
(2001)“Analysis of Multicarrier PWM Methods for a
Table-III
Single-phase Five Level Inverter”, in Proc. 32nd IEEE
FF of output voltage of AMLI for different PWM strategies
Power Electronics Specialists Conference, pp. 1351-
and various values of ma
1356.
ma PD POD APOD VF CO [8] H. Wu, Y. Deng, Y. Liu, and X. He, “A New Clew For
1 432.97 1.6E+09 1.6E+09 2286 337.2 Research on PWM Methods of Multilevel Inverters:
0.95 389.87 1.6E+09 1.6E+09 903.5 117.43 Principle and Applications,” vol. 2, no. 1, 4-12 IEEE
Trans. Industry Applications, pp. 1251-1256, 2002.
0.9 1179.2 1.6E+09 1.6E+09 320 2.08E+09 [9] X. Sun, “Hybrid Control Strategy for A Novel
0.85 7936 1.6E+09 1.6E+09 322.8 2197.14 Asymmetrical Multilevel Inverter,” IEEE Transactions
on Industrial Electronics pp. 5-8, 2010.
0.8 1064 1.6E+09 1.6E+09 682.1 870
[10] R. Taleb, A. Meroufel, and P. Wira, “Neural Network
0.75 1001.6 1.6E+09 1.6E+09 928.9 523.7 Control of Asymmetrical Multilevel Converters,”
0.7 280.48 1.6E+09 1.6E+09 422.9 557.5 Leonardo Journal of Sciences, no. 15, pp. 53-70, 2009.
[11] L. Mihalache , “Asymmetrical PWM Technique for A
Three-Level Hybrid Inverter,” Leonardo Journal of
Sciences, pp. 609-615, 2007.
IV. CONCLUSION
A new hybrid modulation strategy is proposed for a three
phase AMLI which achieves improvement in line to line
voltage harmonics compared to the conventional modulation
techniques. It is observed that COPWM provides better DC
bus utilization and POD technique creates less distortion for
ma=0.7-1.
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