Ammar Masaoud - Academia.edu (original) (raw)

Papers by Ammar Masaoud

IEEE access, 2024

The use of multilevel inverters has gained popularity due to their ability to generate highqualit... more The use of multilevel inverters has gained popularity due to their ability to generate highquality output voltage with reduced harmonic distortion. The performance of these multilevel inverters can be improved by using a low switching frequency modulation scheme as it enables precise amplitude and harmonic control in the output voltage. Determination of optimum switching angles for minimum total harmonic distortion (THD) generally requires complex algorithms with large number of iterations. This work presents a novel approach for calculating optimum switching angles at low frequencies that produces low THD in the output voltage. The calculation process uses only one controlling parameter that allows easy computation of optimum switching angles with a lesser number of iterations. The effectiveness of the calculated switching angles in producing lower THD is verified through simulation in Matlab/Simulink platform as well as experimentally by developing a small-scale lab prototype of symmetric five-level inverter systems. For generalization, the proposed switching angle calculation technique is examined through different levels of inverter for minimum THDs. The superiority of the proposed switching technique is verified through an extensive comparison with other popular low-frequency strategies which revealed that the proposed technique produces lower THD and higher fundamental voltage than those of the Equal Phase (EP), Feed Forward (FF), and Half Height (HH) methods. This feature of producing higher-quality fundamental voltage would make it a preferred choice for high power multi-level inverters. INDEX TERMS Multilevel inverter, optimum switching angle calculation, total harmonic distortion, fundamental voltage, low frequency switching.

Mathematical Problems in Engineering

Climate change and pollution are serious issues that are driving people to adopt renewable energy... more Climate change and pollution are serious issues that are driving people to adopt renewable energy instead of fossil fuels. Most renewable energy technologies rely on atmospheric conditions to generate power. Solar energy is a renewable energy source that causes the least environmental damage. Solar energy can be converted to electricity, which necessitates the use of a PV system. This study presents a design, which analyses the output power performance of PV, using machine learning technique in India and Malaysia; using this, we would get the predicted amount of solar power using different weather conditions for both India and Malaysia. This study is divided into two sections, such as the data collection section and the implementation system. Dataset was collected from a weather NASA website, which took various weather parameters, based on which the model will be evaluated. The proposed research work is developed using ANN and is an amalgamation of statistical regression and neural ...

2019 IEEE 15th International Colloquium on Signal Processing & Its Applications (CSPA), 2019

Multilevel inverters (MLIs) are playing a major role in every sector of power industries, which i... more Multilevel inverters (MLIs) are playing a major role in every sector of power industries, which is growing significantly over the years. Although multilevel inverters are highly applicable, they have some stern disadvantages that need to be dealt with. Some of the most common issues of MLIs include high usage of electric components, highly complex modulation techniques, presence of harmonics and so on. By keeping all these issues into mind, this paper investigates a single phase cross-switched MLI using abridged electric components. Furthermore, it has described a novel and simplified method of implementing sinusoidal pulse width modulation (SPWM) technique. The investigated MLI and the proposed modulation technique is validated by following both simulation and hardware approach. The simulation is performed using MATLAB Simulink software while the hardware prototype of the whole topology is built using TMS320F28335 digital signal processor (DSP) board.

TURKISH JOURNAL OF ELECTRICAL ENGINEERING & COMPUTER SCIENCES, 2020

This paper presents the application of a newly developed 21-level hybrid multilevel inverter. A h... more This paper presents the application of a newly developed 21-level hybrid multilevel inverter. A high frequency modulation technique known as sinusoidal pulse width modulation (SPWM) is applied to the hybrid inverter. This modulation methodology operates the switching sequences of the multilevel inverter to produce the desired 21-level output voltage. To validate the proper application of this inverter, it is further utilized to maintain the speed of a single phase induction motor. The velocity control of the motor is established on the principle of V/f control technique. The speed control strategy along with the compatibility of the SPWM modulation technique were verified by means of simulation and experimental results.

2017 IEEE 15th Student Conference on Research and Development (SCOReD), 2017

Multilevel inverters play an important role in the field of high power and medium voltage control... more Multilevel inverters play an important role in the field of high power and medium voltage control. As the usage of multilevel inverters are significantly increasing in every sector of power system industries, it has also introduced some new challenges. The most common challenge while using a multilevel inverter on high power conditions, is the increased number of power electronic components. This paper investigates a cross switched topology of single phase multilevel inverter with reduced number of power electronic components. It also discusses about the implementation of a simplified one dimensional space vector modulation technique (SVM) to control the multilevel inverter. The studies are performed based on a digital computer simulation approach using the MATLAB Simulink software. Additionally a hardware implementation of the complete topology was also done using TMS320F28335 board. A comprehensive analysis of one dimensional SVM modulation technique is briefly studied to validate the inverter. Finally, a comparative analysis between this topology and other recently developed topologies is discussed.

IEEE Access

Several important advancements in the integration of energy storage into microgrids have fueled a... more Several important advancements in the integration of energy storage into microgrids have fueled a lot of research and development over the last ten years to achieve the global decarbonization goal by 2050. The effective integration of the energy storage system in the microgrid is essential to ensure a safe, reliable, and resilient operation. Nevertheless, the utilization of energy storage in microgrids brings several issues, including poor power quality and intermittence characteristics. To address these concerns, appropriate energy storage controllers and optimization schemes are required to manage and optimize the power efficiently and securely. Although various research works have been performed and published over the years, the analytical assessment of energy storage controllers and optimization schemes integration into microgrids has not been carried out yet. Thus, this paper presents a comprehensive analytical evaluation of energy storage controllers and optimization schemes in Microgrid by recognizing and evaluating the highly influential 110 manuscripts using the Scopus database within the year 2010-2021. The analytical analysis emphasizes the current research trends, keyword evaluation, research classification, country analysis, authorship, and research collaboration. The paper also discusses and compares 24 controllers and 21 optimization schemes in the highly cited 110 manuscripts. Besides, critical discussion and assessment are conducted over 15 emerging subject areas. The constructive analysis identifies the existing limitations and research gaps in the selected 110 papers. By analyzing the existing issues, this manuscript provides several guidelines and suggestions for future improvement. This survey will help to deepen the development concepts to achieve improved power quality, economic prosperity, energy savings, and increased efficiency towards sustainable operation and management in the microgrid. INDEX TERMS Battery storage, microgrid integration, control approaches, energy management system, optimization method, highly cited paper. NOMENCLATURE ACM = Autonomous Control Method ACY = Average Citation Per Year BA = Bat Algorithm BESS = Battery Energy Storage Systems The associate editor coordinating the review of this manuscript and approving it for publication was Lei Wang.

2019 IEEE 15th International Colloquium on Signal Processing & Its Applications (CSPA), 2019

Multilevel inverter (MLI) plays a crucial role in medium voltage and high power applications. Whi... more Multilevel inverter (MLI) plays a crucial role in medium voltage and high power applications. While the usages of MLIs are continuously growing in every area of power industries, it also initiates certain challenges that require attention. The increased number of power electronic components is one of the most challenging issues for multilevel inverters. The output power quality and the semiconductor device ratings of the grid connected high power inverters are largely dependent on the number of power components. Thus, it is required to decrease the overall power components as much as possible while designing these inverters. Therefore, this paper proposes a single phase 7-level cross-switched multilevel inverter that can produce higher voltages utilizing lesser power components. In order to further improve the efficiency of this MLI and enhancing its performance, selective harmonic elimination pulse width modulation (SHE-PWM) control technique is implemented. Here, Newton Raphson algorithm is examined to calculate the switching angles for different modulation indices. The fundamental voltage is obtained by solving the equations in such a way that the desired low order harmonics are eliminated. MATLAB Simulink software has been used to perform the simulation while the hardware model was implemented using digital signal processor eZdsp528335.

2006 IEEE International Conference on Industrial Technology, 2006

In this paper a XILINX FPGA based multilevel PWM single-phase inverter was constructed by adding ... more In this paper a XILINX FPGA based multilevel PWM single-phase inverter was constructed by adding a bi-directional switchs to the conventional bridge topology. The inverter can produce three and five different output voltage levels across the load. XILINX FPGA is a programmable logic device developed by XILINX which is considered as an efficient hardware for rapid prototyping. It is used as a PWM generator to apply the appropriate signals to inverter switches. In addition to XILINX FPGA, Matlab/Simulink software was used for simulation and verification of the proposed circuit before implementation, Simulation and experimental results show that both are in close agreement. I.

Abstract—In this paper, a new configuration of a three-phase five-level multilevel voltage-source... more Abstract—In this paper, a new configuration of a three-phase five-level multilevel voltage-source inverter is introduced. The pro-posed topology constitutes the conventional three-phase two-level bridge with three bidirectional switches. A multilevel dc link using fixed dc voltage supply and cascaded half-bridge is connected in such a way that the proposed inverter outputs the required output voltage levels. The fundamental frequency staircase modulation technique is easily used to generate the appropriate switching gate signals. For the purpose of increasing the number of voltage levels with fewer number of power electronic components, the structure of the proposed inverter is extended and different methods to deter-mine the magnitudes of utilized dc voltage supplies are suggested. Moreover, the prototype of the suggested configuration is manu-factured as the obtained simulation and hardware results ensured the feasibility of the configuration and the compatibility of the modulatio...

IEEE, 2019

Multilevel inverters (MLIs) are playing a major role in every sector of power industries, which i... more Multilevel inverters (MLIs) are playing a major role in every sector of power industries, which is growing significantly over the years. Although multilevel inverters are highly applicable, they have some stern disadvantages that need to be dealt with. Some of the most common issues of MLIs include high usage of electric components, highly complex modulation techniques, presence of harmonics and so on. By keeping all these issues into mind, this paper investigates a single phase cross-switched MLI using abridged electric components. Furthermore, it has described a novel and simplified method of implementing sinusoidal pulse width modulation (SPWM) technique. The investigated MLI and the proposed modulation technique is validated by following both simulation and hardware approach. The simulation is performed using MATLAB Simulink software while the hardware prototype of the whole topology is built using TMS320F28335 digital signal processor (DSP) board.

IEEE Access

Selective harmonic elimination (SHE) technique is used in power inverters to eliminate specific l... more Selective harmonic elimination (SHE) technique is used in power inverters to eliminate specific lower-order harmonics by determining optimum switching angles that are used to generate Pulse Width Modulation (PWM) signals for multilevel inverter (MLI) switches. Various optimization algorithms have been developed to determine the optimum switching angles. However, these techniques are still trapped in local optima. This study proposes an opposition-based quantum bat algorithm (OQBA) to determine these optimum switching angles. This algorithm is formulated by utilizing habitual characteristics of bats. It has advanced learning ability that can effectively remove lower-order harmonics from the output voltage of MLI. It can eventually increase the quality of the output voltage along with the efficiency of the MLI. The performance of the algorithm is evaluated with three different case studies involving 7, 11, and 17-level three-phase MLIs. The results are verified using both simulation and experimental studies. The results showed substantial improvement and superiority compared to other available algorithms both in terms of the harmonics reduction of harmonics and finding the correct solutions. INDEX TERMS Power electronics, multilevel inverter (MLI), optimization algorithm, pulse width modulation (PWM), selective harmonic elimination (SHE), total harmonic distortions (THD).

Ain Shams Engineering Journal

Micromachines

This research proposes a three-phase six-level multilevel inverter depending on twelve-switch thr... more This research proposes a three-phase six-level multilevel inverter depending on twelve-switch three-phase Bridge and multilevel DC-link. The proposed architecture increases the number of voltage levels with less power components than conventional inverters such as the flying capacitor, cascaded H-bridge, diode-clamped and other recently established multilevel inverter topologies. The multilevel DC-link circuit is constructed by connecting three distinct DC voltage supplies, such as single DC supply, half-bridge and full-bridge cells. The purpose of both full-bridge and half-bridge cells is to provide a variable DC voltage with a common voltage step to the three-phase bridge’s mid-point. A vector modulation technique is also employed to achieve the desired output voltage waveforms. The proposed inverter can operate as a six-level or two-level inverter, depending on the magnitude of the modulation indexes. To guarantee the feasibility of the proposed configuration, the proposed invert...

TENCON 2018 - 2018 IEEE Region 10 Conference

International Journal of Power Electronics and Drive Systems (IJPEDS)

This paper introduces a new hybrid topology of multilevel inverter capable of generating 21-level... more This paper introduces a new hybrid topology of multilevel inverter capable of generating 21-level output voltage. The proposed topology is built using the combination of cross-switched bridge and a conventional full H-bridge. Compared to the conventional topologies and other hybrid topologies, the newly introduced multilevel inverter has the ability to maximize the number of voltage levels utilizing lower number of DC voltage sources, integrated bipolar transistor (IGBT) switches and gate drivers. A low frequency modulation technique is used to generate the ideal multilevel output voltage and gate pulses. Furthermore, the proposed topology is validated by building a hardware prototype and obtaining relevant experimental results. The acquired simulated and experimental results indicate the proper functioning of the proposed hybrid topology along with the compatibility of the applied modulation technique.

IEEE Transactions on Power Electronics

This article introduces a novel configuration of multi-level inverter (MLI) with low number of po... more This article introduces a novel configuration of multi-level inverter (MLI) with low number of power electric components. The inverter is a combination of two back to back T-type modules using two cross-connected switches. This inverter can operate using dc sources having either same or different voltage ratings. The proposed inverter can also be extended using cascaded connection to obtain higher voltage levels. This MLI and its extensions are suitable for other applications where high voltage is required. The major feature of this MLI is the formation of negative voltage levels without using any H-bridge circuit. Some other advantages of this MLI are low total harmonic distortion and highly efficient output voltage. A low-frequency modulation technique known as nearest level control is applied to produce the high-quality output voltage. The simulation was done using MATLAB/Simulink, while the hardware prototype is build using TMS320F28335 digital signal processor. The performance of the proposed MLI is validated by obtaining the accurate simulation and experimental results. Index Terms-Cross-switched T-type (CT-type), multilevel in-verter (MLI), nearest level control (NLC), power converters, power electronics.

Journal of Power Electronics, 2014

This paper presents a new configuration for a three-phase multilevel voltage source inverter. The... more This paper presents a new configuration for a three-phase multilevel voltage source inverter. The main bridge is built from a classical three-phase two-level inverter and three bidirectional switches. A variable DC-link employing two unequal DC voltage supplies and four switches is connected to the main circuit in such a way that the proposed inverter produces four levels in the output voltage waveform. In order to obtain the desired switching gate signals, the fundamental frequency staircase modulation technique is successfully implemented. Furthermore, the proposed structure is extended and compared with other types of multilevel inverter topologies. The comparison shows that the proposed inverter requires a smaller number of power components. For a given number of voltage steps N, the proposed inverter requires N/2 DC voltage supplies and N+12 switches connected with N+7 gate driver circuits, while diode clamped or flying capacitor inverters require N-1 DC voltage supplies and 6(N-1) switches connected with 6(N-1) gate driver circuits. A prototype of the introduced configuration has been manufactured and the obtained simulation and experimental results ensure the feasibility of the proposed topology and the validity of the implemented modulation technique.

2016 IEEE 8th International Power Electronics and Motion Control Conference (IPEMC-ECCE Asia), 2016

TURKISH JOURNAL OF ELECTRICAL ENGINEERING & COMPUTER SCIENCES, 2016

This paper introduces a new three-phase three-level voltage source inverter. The proposed topolog... more This paper introduces a new three-phase three-level voltage source inverter. The proposed topology constitutes the conventional three-phase two-level inverter with three bidirectional switches. For purpose of generating the appropriate switching gate signals, two different commutation strategies are suggested and analyzed. A comparison between both strategies in terms of power losses and efficiency are presented. To ensure the feasibility of the proposed configuration with its suggested commutation strategies, the prototype of the proposed inverter was manufactured and the experimental results are given.

IEEE access, 2024

The use of multilevel inverters has gained popularity due to their ability to generate highqualit... more The use of multilevel inverters has gained popularity due to their ability to generate highquality output voltage with reduced harmonic distortion. The performance of these multilevel inverters can be improved by using a low switching frequency modulation scheme as it enables precise amplitude and harmonic control in the output voltage. Determination of optimum switching angles for minimum total harmonic distortion (THD) generally requires complex algorithms with large number of iterations. This work presents a novel approach for calculating optimum switching angles at low frequencies that produces low THD in the output voltage. The calculation process uses only one controlling parameter that allows easy computation of optimum switching angles with a lesser number of iterations. The effectiveness of the calculated switching angles in producing lower THD is verified through simulation in Matlab/Simulink platform as well as experimentally by developing a small-scale lab prototype of symmetric five-level inverter systems. For generalization, the proposed switching angle calculation technique is examined through different levels of inverter for minimum THDs. The superiority of the proposed switching technique is verified through an extensive comparison with other popular low-frequency strategies which revealed that the proposed technique produces lower THD and higher fundamental voltage than those of the Equal Phase (EP), Feed Forward (FF), and Half Height (HH) methods. This feature of producing higher-quality fundamental voltage would make it a preferred choice for high power multi-level inverters. INDEX TERMS Multilevel inverter, optimum switching angle calculation, total harmonic distortion, fundamental voltage, low frequency switching.

Mathematical Problems in Engineering

Climate change and pollution are serious issues that are driving people to adopt renewable energy... more Climate change and pollution are serious issues that are driving people to adopt renewable energy instead of fossil fuels. Most renewable energy technologies rely on atmospheric conditions to generate power. Solar energy is a renewable energy source that causes the least environmental damage. Solar energy can be converted to electricity, which necessitates the use of a PV system. This study presents a design, which analyses the output power performance of PV, using machine learning technique in India and Malaysia; using this, we would get the predicted amount of solar power using different weather conditions for both India and Malaysia. This study is divided into two sections, such as the data collection section and the implementation system. Dataset was collected from a weather NASA website, which took various weather parameters, based on which the model will be evaluated. The proposed research work is developed using ANN and is an amalgamation of statistical regression and neural ...

2019 IEEE 15th International Colloquium on Signal Processing & Its Applications (CSPA), 2019

Multilevel inverters (MLIs) are playing a major role in every sector of power industries, which i... more Multilevel inverters (MLIs) are playing a major role in every sector of power industries, which is growing significantly over the years. Although multilevel inverters are highly applicable, they have some stern disadvantages that need to be dealt with. Some of the most common issues of MLIs include high usage of electric components, highly complex modulation techniques, presence of harmonics and so on. By keeping all these issues into mind, this paper investigates a single phase cross-switched MLI using abridged electric components. Furthermore, it has described a novel and simplified method of implementing sinusoidal pulse width modulation (SPWM) technique. The investigated MLI and the proposed modulation technique is validated by following both simulation and hardware approach. The simulation is performed using MATLAB Simulink software while the hardware prototype of the whole topology is built using TMS320F28335 digital signal processor (DSP) board.

TURKISH JOURNAL OF ELECTRICAL ENGINEERING & COMPUTER SCIENCES, 2020

This paper presents the application of a newly developed 21-level hybrid multilevel inverter. A h... more This paper presents the application of a newly developed 21-level hybrid multilevel inverter. A high frequency modulation technique known as sinusoidal pulse width modulation (SPWM) is applied to the hybrid inverter. This modulation methodology operates the switching sequences of the multilevel inverter to produce the desired 21-level output voltage. To validate the proper application of this inverter, it is further utilized to maintain the speed of a single phase induction motor. The velocity control of the motor is established on the principle of V/f control technique. The speed control strategy along with the compatibility of the SPWM modulation technique were verified by means of simulation and experimental results.

2017 IEEE 15th Student Conference on Research and Development (SCOReD), 2017

Multilevel inverters play an important role in the field of high power and medium voltage control... more Multilevel inverters play an important role in the field of high power and medium voltage control. As the usage of multilevel inverters are significantly increasing in every sector of power system industries, it has also introduced some new challenges. The most common challenge while using a multilevel inverter on high power conditions, is the increased number of power electronic components. This paper investigates a cross switched topology of single phase multilevel inverter with reduced number of power electronic components. It also discusses about the implementation of a simplified one dimensional space vector modulation technique (SVM) to control the multilevel inverter. The studies are performed based on a digital computer simulation approach using the MATLAB Simulink software. Additionally a hardware implementation of the complete topology was also done using TMS320F28335 board. A comprehensive analysis of one dimensional SVM modulation technique is briefly studied to validate the inverter. Finally, a comparative analysis between this topology and other recently developed topologies is discussed.

IEEE Access

Several important advancements in the integration of energy storage into microgrids have fueled a... more Several important advancements in the integration of energy storage into microgrids have fueled a lot of research and development over the last ten years to achieve the global decarbonization goal by 2050. The effective integration of the energy storage system in the microgrid is essential to ensure a safe, reliable, and resilient operation. Nevertheless, the utilization of energy storage in microgrids brings several issues, including poor power quality and intermittence characteristics. To address these concerns, appropriate energy storage controllers and optimization schemes are required to manage and optimize the power efficiently and securely. Although various research works have been performed and published over the years, the analytical assessment of energy storage controllers and optimization schemes integration into microgrids has not been carried out yet. Thus, this paper presents a comprehensive analytical evaluation of energy storage controllers and optimization schemes in Microgrid by recognizing and evaluating the highly influential 110 manuscripts using the Scopus database within the year 2010-2021. The analytical analysis emphasizes the current research trends, keyword evaluation, research classification, country analysis, authorship, and research collaboration. The paper also discusses and compares 24 controllers and 21 optimization schemes in the highly cited 110 manuscripts. Besides, critical discussion and assessment are conducted over 15 emerging subject areas. The constructive analysis identifies the existing limitations and research gaps in the selected 110 papers. By analyzing the existing issues, this manuscript provides several guidelines and suggestions for future improvement. This survey will help to deepen the development concepts to achieve improved power quality, economic prosperity, energy savings, and increased efficiency towards sustainable operation and management in the microgrid. INDEX TERMS Battery storage, microgrid integration, control approaches, energy management system, optimization method, highly cited paper. NOMENCLATURE ACM = Autonomous Control Method ACY = Average Citation Per Year BA = Bat Algorithm BESS = Battery Energy Storage Systems The associate editor coordinating the review of this manuscript and approving it for publication was Lei Wang.

2019 IEEE 15th International Colloquium on Signal Processing & Its Applications (CSPA), 2019

Multilevel inverter (MLI) plays a crucial role in medium voltage and high power applications. Whi... more Multilevel inverter (MLI) plays a crucial role in medium voltage and high power applications. While the usages of MLIs are continuously growing in every area of power industries, it also initiates certain challenges that require attention. The increased number of power electronic components is one of the most challenging issues for multilevel inverters. The output power quality and the semiconductor device ratings of the grid connected high power inverters are largely dependent on the number of power components. Thus, it is required to decrease the overall power components as much as possible while designing these inverters. Therefore, this paper proposes a single phase 7-level cross-switched multilevel inverter that can produce higher voltages utilizing lesser power components. In order to further improve the efficiency of this MLI and enhancing its performance, selective harmonic elimination pulse width modulation (SHE-PWM) control technique is implemented. Here, Newton Raphson algorithm is examined to calculate the switching angles for different modulation indices. The fundamental voltage is obtained by solving the equations in such a way that the desired low order harmonics are eliminated. MATLAB Simulink software has been used to perform the simulation while the hardware model was implemented using digital signal processor eZdsp528335.

2006 IEEE International Conference on Industrial Technology, 2006

In this paper a XILINX FPGA based multilevel PWM single-phase inverter was constructed by adding ... more In this paper a XILINX FPGA based multilevel PWM single-phase inverter was constructed by adding a bi-directional switchs to the conventional bridge topology. The inverter can produce three and five different output voltage levels across the load. XILINX FPGA is a programmable logic device developed by XILINX which is considered as an efficient hardware for rapid prototyping. It is used as a PWM generator to apply the appropriate signals to inverter switches. In addition to XILINX FPGA, Matlab/Simulink software was used for simulation and verification of the proposed circuit before implementation, Simulation and experimental results show that both are in close agreement. I.

Abstract—In this paper, a new configuration of a three-phase five-level multilevel voltage-source... more Abstract—In this paper, a new configuration of a three-phase five-level multilevel voltage-source inverter is introduced. The pro-posed topology constitutes the conventional three-phase two-level bridge with three bidirectional switches. A multilevel dc link using fixed dc voltage supply and cascaded half-bridge is connected in such a way that the proposed inverter outputs the required output voltage levels. The fundamental frequency staircase modulation technique is easily used to generate the appropriate switching gate signals. For the purpose of increasing the number of voltage levels with fewer number of power electronic components, the structure of the proposed inverter is extended and different methods to deter-mine the magnitudes of utilized dc voltage supplies are suggested. Moreover, the prototype of the suggested configuration is manu-factured as the obtained simulation and hardware results ensured the feasibility of the configuration and the compatibility of the modulatio...

IEEE, 2019

Multilevel inverters (MLIs) are playing a major role in every sector of power industries, which i... more Multilevel inverters (MLIs) are playing a major role in every sector of power industries, which is growing significantly over the years. Although multilevel inverters are highly applicable, they have some stern disadvantages that need to be dealt with. Some of the most common issues of MLIs include high usage of electric components, highly complex modulation techniques, presence of harmonics and so on. By keeping all these issues into mind, this paper investigates a single phase cross-switched MLI using abridged electric components. Furthermore, it has described a novel and simplified method of implementing sinusoidal pulse width modulation (SPWM) technique. The investigated MLI and the proposed modulation technique is validated by following both simulation and hardware approach. The simulation is performed using MATLAB Simulink software while the hardware prototype of the whole topology is built using TMS320F28335 digital signal processor (DSP) board.

IEEE Access

Selective harmonic elimination (SHE) technique is used in power inverters to eliminate specific l... more Selective harmonic elimination (SHE) technique is used in power inverters to eliminate specific lower-order harmonics by determining optimum switching angles that are used to generate Pulse Width Modulation (PWM) signals for multilevel inverter (MLI) switches. Various optimization algorithms have been developed to determine the optimum switching angles. However, these techniques are still trapped in local optima. This study proposes an opposition-based quantum bat algorithm (OQBA) to determine these optimum switching angles. This algorithm is formulated by utilizing habitual characteristics of bats. It has advanced learning ability that can effectively remove lower-order harmonics from the output voltage of MLI. It can eventually increase the quality of the output voltage along with the efficiency of the MLI. The performance of the algorithm is evaluated with three different case studies involving 7, 11, and 17-level three-phase MLIs. The results are verified using both simulation and experimental studies. The results showed substantial improvement and superiority compared to other available algorithms both in terms of the harmonics reduction of harmonics and finding the correct solutions. INDEX TERMS Power electronics, multilevel inverter (MLI), optimization algorithm, pulse width modulation (PWM), selective harmonic elimination (SHE), total harmonic distortions (THD).

Ain Shams Engineering Journal

Micromachines

This research proposes a three-phase six-level multilevel inverter depending on twelve-switch thr... more This research proposes a three-phase six-level multilevel inverter depending on twelve-switch three-phase Bridge and multilevel DC-link. The proposed architecture increases the number of voltage levels with less power components than conventional inverters such as the flying capacitor, cascaded H-bridge, diode-clamped and other recently established multilevel inverter topologies. The multilevel DC-link circuit is constructed by connecting three distinct DC voltage supplies, such as single DC supply, half-bridge and full-bridge cells. The purpose of both full-bridge and half-bridge cells is to provide a variable DC voltage with a common voltage step to the three-phase bridge’s mid-point. A vector modulation technique is also employed to achieve the desired output voltage waveforms. The proposed inverter can operate as a six-level or two-level inverter, depending on the magnitude of the modulation indexes. To guarantee the feasibility of the proposed configuration, the proposed invert...

TENCON 2018 - 2018 IEEE Region 10 Conference

International Journal of Power Electronics and Drive Systems (IJPEDS)

This paper introduces a new hybrid topology of multilevel inverter capable of generating 21-level... more This paper introduces a new hybrid topology of multilevel inverter capable of generating 21-level output voltage. The proposed topology is built using the combination of cross-switched bridge and a conventional full H-bridge. Compared to the conventional topologies and other hybrid topologies, the newly introduced multilevel inverter has the ability to maximize the number of voltage levels utilizing lower number of DC voltage sources, integrated bipolar transistor (IGBT) switches and gate drivers. A low frequency modulation technique is used to generate the ideal multilevel output voltage and gate pulses. Furthermore, the proposed topology is validated by building a hardware prototype and obtaining relevant experimental results. The acquired simulated and experimental results indicate the proper functioning of the proposed hybrid topology along with the compatibility of the applied modulation technique.

IEEE Transactions on Power Electronics

This article introduces a novel configuration of multi-level inverter (MLI) with low number of po... more This article introduces a novel configuration of multi-level inverter (MLI) with low number of power electric components. The inverter is a combination of two back to back T-type modules using two cross-connected switches. This inverter can operate using dc sources having either same or different voltage ratings. The proposed inverter can also be extended using cascaded connection to obtain higher voltage levels. This MLI and its extensions are suitable for other applications where high voltage is required. The major feature of this MLI is the formation of negative voltage levels without using any H-bridge circuit. Some other advantages of this MLI are low total harmonic distortion and highly efficient output voltage. A low-frequency modulation technique known as nearest level control is applied to produce the high-quality output voltage. The simulation was done using MATLAB/Simulink, while the hardware prototype is build using TMS320F28335 digital signal processor. The performance of the proposed MLI is validated by obtaining the accurate simulation and experimental results. Index Terms-Cross-switched T-type (CT-type), multilevel in-verter (MLI), nearest level control (NLC), power converters, power electronics.

Journal of Power Electronics, 2014

This paper presents a new configuration for a three-phase multilevel voltage source inverter. The... more This paper presents a new configuration for a three-phase multilevel voltage source inverter. The main bridge is built from a classical three-phase two-level inverter and three bidirectional switches. A variable DC-link employing two unequal DC voltage supplies and four switches is connected to the main circuit in such a way that the proposed inverter produces four levels in the output voltage waveform. In order to obtain the desired switching gate signals, the fundamental frequency staircase modulation technique is successfully implemented. Furthermore, the proposed structure is extended and compared with other types of multilevel inverter topologies. The comparison shows that the proposed inverter requires a smaller number of power components. For a given number of voltage steps N, the proposed inverter requires N/2 DC voltage supplies and N+12 switches connected with N+7 gate driver circuits, while diode clamped or flying capacitor inverters require N-1 DC voltage supplies and 6(N-1) switches connected with 6(N-1) gate driver circuits. A prototype of the introduced configuration has been manufactured and the obtained simulation and experimental results ensure the feasibility of the proposed topology and the validity of the implemented modulation technique.

2016 IEEE 8th International Power Electronics and Motion Control Conference (IPEMC-ECCE Asia), 2016

TURKISH JOURNAL OF ELECTRICAL ENGINEERING & COMPUTER SCIENCES, 2016

This paper introduces a new three-phase three-level voltage source inverter. The proposed topolog... more This paper introduces a new three-phase three-level voltage source inverter. The proposed topology constitutes the conventional three-phase two-level inverter with three bidirectional switches. For purpose of generating the appropriate switching gate signals, two different commutation strategies are suggested and analyzed. A comparison between both strategies in terms of power losses and efficiency are presented. To ensure the feasibility of the proposed configuration with its suggested commutation strategies, the prototype of the proposed inverter was manufactured and the experimental results are given.