基于桥臂能量平衡的MMC故障容错控制策略  

Fault Tolerant Control Strategy for MMC Based on Bridge Arm Energy Balance

作　　者：徐浩文 王江 孟致丞 杨兴武 XU Hao-wen;WANG Jiang;MENG Zhi-cheng;YANG Xing-wu(Shanghai University of Electric Power,Shanghai 200090,China;不详)

机构地区：[1]上海电力大学,电气工程学院,上海200090 [2]国网陕西省电力有限公司宝鸡供电公司,陕西宝鸡721000

出　　处：《电力电子技术》2024年第7期23-26,共4页Power Electronics

基　　金：上海市科技计划(23010501200)。

摘　　要：模块化多电平换流器(MMC)子模块(SM)带故障运行时,保证MMC电容电压平衡及减少电容电压纹波是提高换流器运行可靠性的关键。为解决上述问题,此处提出了一种基于桥臂能量平衡、降低开关频率(RSF)算法的MMC容错控制策略。首先,基于上下桥臂的输入功率积分,得到其公共分量与微分分量,通过环流注入的方式实现能量平衡与电容器电压稳定。其次,建立故障后改进的电容电压成本函数,设定故障标志,绕过故障SM。最后,基于硬件在环(HIL)实验平台进行实验研究,结果表明,所提方法可在MMC发生故障后保证在桥臂不对称运行时输出电压和电流波形质量不受影响,且不会增加成本或复杂性。When the modular multilevel converter(MMC)submodule(SM)operates with faults,ensuring the voltage balance of the MMC capacitor and reducing the voltage ripple of the capacitor is the key to improving the reliability of the converter operation.To address the issues mentioned above,a fault tolerant control strategy for MMC based on bridge arm energy balance and reduced switching frequency(RSF)algorithm is proposed.Firstly,based on the input power integration of the upper and lower bridge arms,the common and differential components are obtained,and en-ergy balance and capacitor voltage stability are achieved through circulation injection.Secondly,an improved capacitor voltage cost function after the fault is established,fault markers are set,and the fault SM is bypassed.Finally,experi-mental research is conducted based on the hardware in the loop(HIL)platform,and the results show that the propo-sed method can ensure that the output voltage and current waveforms quality are not affected during asymmetric oper-ation of the bridge arm after MMC failure,without increasing cost or complexity.

关 键 词：模块化多电平换流器 故障容错控制 桥臂能量平衡 环流注入 

分 类 号：TM46[电气工程—电器]