A Comparative Study of Harmonic Distortion in Multicarrier Based PWM Switching Techniques for Cascaded H-Bridge Inverters

Advances in Electrical and Computer Engineering

HAMEDANI, P¹ 

关键词: converters;    harmonic distortion;    inverters;    modulation;    pulse width modulation;   

DOI  :  10.4316/AECE.2016.03003

学科分类：计算机科学（综合）

来源: Universitatea "Stefan cel Mare" din Suceava

【 摘 要 】

Multicarrier based PWM switching patterns are commonly utilized to control Cascaded H-bridge (CHB) inverters. The main contribution of this paper is to comprehensively investigate the effect of various multicarrier based PWM techniques on harmonic content of the CHB multilevel inverter. In order to achieve this, both of the CHB output voltage and the input current at power grid side have been taken into account. In this work, various PWM modulations such as level shifted (LS), phase shifted (PS), hybrid, and rotative-LS (R-LS) have been studied through both simulation and implementation of an experimental setup. By extracting the frequency spectrum and calculation of THD and WTHD indices, a quantitative comparative study of various multicarrier PWM techniques has been carried out. According to the results, the R-LS-PWM methods (i.e. R-PD, and two new proposed R-POD and R-APOD) reduce the harmonic distortion of the input current while keeping the obvious advantage of LS-PWM modulation such as lower harmonic distortion of the output voltage. Specially, the proposed R-APOD-PWM modulation offers these preferable privileges at odd frequency ratio values.

【 授权许可】

Unknown