WANG M D, ZHANG Q F, WANG W H , et al.M3C control strategy based on capacitor voltage optimization sorting algorithm[J].Journal of Henan Polytechnic University(Natural Science) ,2026,45(5):1-10.

doi:10.16186/j.cnki.1673-9787.2025090053

Received:2025/09/22

Revised:2025/12/18

Published:2026-07-24

M3C control strategy based on capacitor voltage optimization sorting algorithm

Wang Mingdong1, Zhang Qifan2, Wang Wenhao3, Li Zhongwen1

1.School of Electrical and Information Engineering， Zhengzhou University， Zhengzhou  450001， Henan， China；2.Ultra High Voltage Company， State Grid Henan Electric Power Company， Zhengzhou  450001， Henan， China；3.State Grid Zhumadian Power Supply Company， Zhumadian  463000， Henan， China

Abstract: Objectives In order to address issues including the high number of comparisons in the traditional sub-module capacitor voltage sorting algorithm and the significant switch losses due to repeated switching of the same sub-module with the same number of sub-modules，an optimized sorting algorithm was proposed.  Methods This algorithm grouped the capacitor voltage values of the sub-modules and performed sorting only within each group， effectively avoiding unnecessary repetitive sorting. Furthermore， by setting the allowable range of capacitor voltage fluctuations， the switch frequency of the sub-modules was optimized.  Results Simulation results demonstrated that the proposed optimization sorting algorithm effectively reduced the number of sorting times and shortened the sorting time without affecting the capacitor voltage balance. Moreover， after switch frequency optimization， the switching frequency of the sub-module switches was significantly reduced.  Conclusions Under the same conditions， the optimized sorting algorithm improved sorting efficiency without affecting the sub-module capacitor voltage and switch frequency. After the switch frequency optimization， unnecessary repetitive switching of the switches was effectively avoided when the sub-module capacitor voltage fluctuated slightly， reducing and the switching losses was reduced.

Key words:modular multilevel matrix converter;modulation strategy;optimize sorting;switching frequency