An Improved SPWM Strategy to Reduce Switching in Cascaded Multilevel Inverters

Xiucheng Dong; Xiaomei Yu; Zhiwen Yuan; Yankun Xia; Yu Li

An Improved SPWM Strategy to Reduce Switching in Cascaded Multilevel Inverters

Vol. 16, No. 2, pp. 490-497, Mar. 2016

10.6113/JPE.2016.16.2.490

Cascaded multi-level inverter

Improved SPWM strategy

Unipolar SPWM

Unnecessary switching frequency

PDF

Abstract

The analysis of the switch status of each unit module of a cascaded multi-level inverter reveals that the working condition of the switch of a chopper arm causes unnecessary switching under the conventional unipolar sinusoidal pulse width modulation (SPWM). With an increase in the number of cascaded multilevel inverters, the superposition of unnecessary switching gradually occurs. In this work, we propose an improved SPWM strategy to reduce switching in cascaded multilevel inverters. Specifically, we analyze the switch state of the switch tube of a chopper arm of an H-bridge unit. The redundant switch is then removed, thereby reducing the switching frequency. Unlike the conventional unipolar SPWM technique, the improved SPWM method greatly reduces switching without altering the output quality of inverters. The conventional unipolar SPWM technique and the proposed method are applied to a five-level inverter. Simulation results show the superiority of the proposed strategy. Finally, a prototype is built in the laboratory. Experimental results verify the correctness of the proposed modulation strategy.

Statistics

Show / Hide Statistics

Cumulative Counts from September 30th, 2019
Multiple requests among the same browser session are counted as one view. If you mouse over a chart, the values of data points will be shown.

Cite this article

[IEEE Style]

X. Dong, X. Yu, Z. Yuan, Y. Xia, Y. Li, "An Improved SPWM Strategy to Reduce Switching in Cascaded Multilevel Inverters," Journal of Power Electronics, vol. 16, no. 2, pp. 490-497, 2016. DOI: 10.6113/JPE.2016.16.2.490.

[ACM Style]

Xiucheng Dong, Xiaomei Yu, Zhiwen Yuan, Yankun Xia, and Yu Li. 2016. An Improved SPWM Strategy to Reduce Switching in Cascaded Multilevel Inverters. Journal of Power Electronics, 16, 2, (2016), 490-497. DOI: 10.6113/JPE.2016.16.2.490.