电力系统保护与控制2023，Vol.51Issue(24)：66-76,11.DOI:10.19783/j.cnki.pspc.230625
基于T型三电平变换器的优化损耗分布控制策略
Optimal loss distribution control strategy based on a T-type three-level converter
摘要
Abstract
In conventional modulation strategy,there is a serious problem of uneven loss between inner and outer switches of a T-type three-level converter.When the converter's modulation ratio is below 0.57,the inner switch temperature rise is significantly higher than that of the outer switch,and this issue is even worse during a low voltage ride through(LVRT)operation.It will threaten the long-term reliable operation of the converter.Therefore,a discontinuous pulse width modulation strategy based on optimal loss distribution is proposed.This adopts new switching sequences in corresponding regions of the space vector diagram.The clamping mode of each phase is to be clamped to the positive or negative pole so as to redistribute the current in outer and inner switches.This new modulation strategy adopts a five-stage wave mode.This can not only effectively improve the loss distribution of the inner and outer switches,but also enhance the efficiency of the converter.The balance of midpoint voltage is maintained through redundant small vector complementary sequences.The new modulation strategy has a unified carrier-modulation method.Finally,the effectiveness of the proposed loss distribution modulation strategy is verified by electrical-thermal co-simulation.关键词
T型三电平变换器/损耗均衡/不连续调制/中点电压控制Key words
T-type three-level converter/loss balance/discontinuous modulation/midpoint voltage control引用本文复制引用
周思邈,马伏军,许明春,丁红旗,黄格林,章程,王俊攀..基于T型三电平变换器的优化损耗分布控制策略[J].电力系统保护与控制,2023,51(24):66-76,11.基金项目
This work is supported by the National Natural Science Foundation of China(No.51977067). 国家自然科学基金项目资助(51977067) （No.51977067）
湖南省研究生科研创新项目资助(CX20220393) （CX20220393）
湖南省自然科学基金优青项目资助(2020JJ3010) （2020JJ3010）
