Increasing demands for improvement in power quality and power capacity have contributed to development of switched-capacitor multilevel inverters(SCMLIs).Recently developed SCMLIs enable single-stage voltage boosting,...Increasing demands for improvement in power quality and power capacity have contributed to development of switched-capacitor multilevel inverters(SCMLIs).Recently developed SCMLIs enable single-stage voltage boosting,as well as inversion resulting in step-up ac output.Towards reduction in number of components,this paper introduces a boost type singlesource nine-level(9-level)SCMLI employing two capacitors and three diodes.Owing to the series-parallel connection process,capacitor voltages are inherently balanced and assist in quadruple voltage boosting from a single-source.Maximum voltage stress across semiconductor devices is limited to twice input voltage only.Using a minimum number of components,the proposed SCMLI can be extended to increase voltage levels without additional dc input.Each extension module adds two additional voltage steps in the output while maintaining maximum voltage stress the same as 9-level circuit.Followed by in-depth analysis of circuit operation and power losses,a thorough comparison of recently developed single-phase 9-level MLIs is carried out,which verifies design superiority.Extensive simulation and experimental results are presented to verify the prominent features of the 9-level SCMLI under dynamic operating conditions.展开更多
Multilevel inverter has become increasingly popular in recent years due to advantages of high power quality waveforms, low switching losses, and high-voltage capability. A novel multilevel inverter with minimum number...Multilevel inverter has become increasingly popular in recent years due to advantages of high power quality waveforms, low switching losses, and high-voltage capability. A novel multilevel inverter with minimum number of separated DC sources is presented in this paper. Three-phase output voltages of this inverter can easily be balanced because they are synthesized by using the same DC sources. A harmonic reduction method eliminating both the 5th and 7th harmonics is proposed. Finally, comparison results and spectral analysis are presented. Key words multilevel inverter - topology - DC source - harmonic reduction - spectrum Project supported by the Postdoctoral Science Foundation of Shanghai (Grant No. kO7)展开更多
This paper focuses on a Z source cascaded multilevel inverter which is designed to minimize harmonics in the output voltage. A balanced dc-link peak voltage can be achieved. The power generation module is built by PV ...This paper focuses on a Z source cascaded multilevel inverter which is designed to minimize harmonics in the output voltage. A balanced dc-link peak voltage can be achieved. The power generation module is built by PV panels which are connected to Z-Source Cascade H-bridge inverter. Cascaded multilevel inverter can achieve the distributed maximum power point tracking to increase the system efficiency and achieve high voltage/high power grid tie without a transformer. This paper analyzes the different PWM switching scheme and the operating states of a ZSI module and comparison is made with different PWM and total harmonic distortion of various PWM schemes.展开更多
文摘Increasing demands for improvement in power quality and power capacity have contributed to development of switched-capacitor multilevel inverters(SCMLIs).Recently developed SCMLIs enable single-stage voltage boosting,as well as inversion resulting in step-up ac output.Towards reduction in number of components,this paper introduces a boost type singlesource nine-level(9-level)SCMLI employing two capacitors and three diodes.Owing to the series-parallel connection process,capacitor voltages are inherently balanced and assist in quadruple voltage boosting from a single-source.Maximum voltage stress across semiconductor devices is limited to twice input voltage only.Using a minimum number of components,the proposed SCMLI can be extended to increase voltage levels without additional dc input.Each extension module adds two additional voltage steps in the output while maintaining maximum voltage stress the same as 9-level circuit.Followed by in-depth analysis of circuit operation and power losses,a thorough comparison of recently developed single-phase 9-level MLIs is carried out,which verifies design superiority.Extensive simulation and experimental results are presented to verify the prominent features of the 9-level SCMLI under dynamic operating conditions.
文摘Multilevel inverter has become increasingly popular in recent years due to advantages of high power quality waveforms, low switching losses, and high-voltage capability. A novel multilevel inverter with minimum number of separated DC sources is presented in this paper. Three-phase output voltages of this inverter can easily be balanced because they are synthesized by using the same DC sources. A harmonic reduction method eliminating both the 5th and 7th harmonics is proposed. Finally, comparison results and spectral analysis are presented. Key words multilevel inverter - topology - DC source - harmonic reduction - spectrum Project supported by the Postdoctoral Science Foundation of Shanghai (Grant No. kO7)
文摘This paper focuses on a Z source cascaded multilevel inverter which is designed to minimize harmonics in the output voltage. A balanced dc-link peak voltage can be achieved. The power generation module is built by PV panels which are connected to Z-Source Cascade H-bridge inverter. Cascaded multilevel inverter can achieve the distributed maximum power point tracking to increase the system efficiency and achieve high voltage/high power grid tie without a transformer. This paper analyzes the different PWM switching scheme and the operating states of a ZSI module and comparison is made with different PWM and total harmonic distortion of various PWM schemes.
