基于隔离型模块化多电平直流/直流变换器的总谐波畸变率优化调制控制策略  

Optimal Modulation Control Strategy for Total Harmonic Distortion Rate Based on Isolated Modular Multilevel AC/DC Converter

作　　者：孔祥平 宾子君 邓富金 孙振威 耿佳豪 KONG Xiangping;BIN Zijun;DENG Fujin;SUN Zhenwei;GENG Jiahao(Power Grid Technology Center State Grid Jiangsu Electric Power Company,Nanjing 211103,Jiangsu Province,China;School of Electrical Engineering,Southeast University,Nanjing 210096,Jiangsu Province,China)

机构地区：[1]国网江苏省电力有限公司电力科学研究院,江苏省南京市211103 [2]东南大学电气工程学院,江苏省南京市210096

出　　处：《现代电力》2025年第2期377-384,共8页Modern Electric Power

基　　金：国网江苏省电力有限公司科技项目(J2021179)。

摘　　要：为解决模块化多电平直流/直流变换器(modular multilevel DC/DC converter,MMDC)的调制策略中,准两电平调制策略的交流侧电压电流中仍存在大量高次谐波,导致隔离变压器的损耗增加的问题,首先通过分析得到功率器件开关角与变压器一次侧线电压总谐波畸变率(total harmonic distortion,THD)的关系,进而提出一种变占空比和幅值的THD优化调制策略,通过改变开关角降低变压器一次侧线电压电流THD,从而减小变压器损耗。最后通过仿真软件PSCAD/EMTDC验证了所提基于THD优化调制控制策略的可行性。To solve the problem of increase of isolation transformer losses led by a large number of high harmonics existing in the AC side voltage and current of quasi two-level modulation strategy in modular multilevel DC/DC converter(abbr.MMDC),firstly,the relationship between the switching angle of the power device and the total harmonic distortion(abbr.THD)of the primary side line voltage of the transformer was obtained by analysis.Secondly,a THD optimization modulation strategy with variable duty cycle and amplitude was proposed.The THD of the primary side line voltage and current of the transformer were reduced by changing the switch angle to reduce the transformer losses.Finally,the feasibility of the proposed THD-based the optimal modulation control strategy was verified by simulation software PSCAD/EMTDC.

关 键 词：DC/DC变换器 模块化多电平 准两电平调制 总谐波畸变率 变压器谐波损耗 优化开关角 

分 类 号：TM721.1[电气工程—电力系统及自动化]