Power Balance Control and Optimization Methods With Output Voltage Rotation for Cascaded Multilevel Inverter

Affiliation of Author(s):自动化学院

Journal:Zhongguo Dianji Gongcheng Xuebao

Abstract:Under the level-shifted pulse width modulation (LS-PWM) strategy, the expected output voltage of the cascaded H-bridge (CHB) inverter is superimposed by a variety of basic voltage waveforms, and the output power of every cell may be different with the different basic voltage waveforms. Therefore, to achieve the power balance among the cascaded cells, the output voltage of every cascaded cell must include all the basic voltage waveforms which have different output power in a certain time. In order to achieve this goal, a power balance control method and its optimization method based on carrier rotation in 1/4 output period were proposed in this paper, which combine the redundancy characteristics of the synthesis methods for the inverter's output levels and LS-PWM strategy control degree of freedom. The proposed power balance control method can realize the power balance among the cascaded cells in the shortest time without changing the harmonic characteristics of the output voltage of the inverter. Three cells cascaded multilevel inverter was taking as the example in this paper for the theoretical analysis, and simulation and experimental results were given to verify the correctness of the theoretical analysis. © 2018 Chin. Soc. for Elec. Eng.

ISSN No.:0258-8013

Translation or Not:no

Date of Publication:2018-02-20

Co-author:Xu, Yaming,Na, Xianlong,Sun, Jianbo

Correspondence Author:cz

Date of Publication:2018-02-20