基于改进型单极全桥子模块的新型MMC  

New MMC Based on Modified Unipolar Full-bridge Sub-module

作　　者：薛尧[1] 杨晓峰[1] 陈博伟[1] 林智钦[1] 郑琼林[1] 

机构地区：[1]北京交通大学电气工程学院,北京100044

出　　处：《电源学报》2018年第1期1-7,共7页Journal of Power Supply

基　　金：中央高校基本科研业务费专项资金资助项目(E16JB00080)~~

摘　　要：提出了一种改进型的单极全桥子模块结构MUFBSM(modified unipolar full bridge sub module),其本质是在单极全桥子模块结构UFBSM(unipolar full bridge sub module)的二极管支路添加一个串联电阻。系统正常工作时,MUFBSM不会增加额外的损耗;当系统检测到直流侧故障并闭锁后,MUFBSM中的串联电阻接入故障电流通路,增强了故障回路的阻尼效果并消耗部分系统储存能量,加快了故障电流清除速度,降低了子模块电容电压上升幅值。然后分析了UFBSM和MUFBSM混合型模块化多电平变换器的故障机理,分析了串联电阻的取值依据。Matlab/Simulink仿真结果验证了MUFBSM的可行性和有效性。In this paper, a modified unipolar full-bridge sub-module （MUFBSM） is proposed by adding a series res-istance to the diode branch of unipolar full-bridge sub-module （UFBSM） . When the system is in a normal operation state, MUFBSM will not generate extra power loss; when a DC fault is detected and MUFBSMs are thus blocked, the series re-sistance will be connected to the fault current path and provide a higher damping effect on the fault current loop, which dissipates part of the initial energy storage of the system. Therefore, the fault current will fall into zero immediately, and the amplitude of capacitor voltage rising in the sub-module is limited. The fault mechanisms of a hybrid modular multi-level converter（HMMC） with UFBSMs and MUFBSMs are analyzed, together with the evaluation on the values of series resistance. Simulation results in Matlab/Simulink validate the feasibility and effectiveness of MUFBSM.

关 键 词：模块化多电平换流器 改进型单极全桥子模块 直流侧故障穿越 串联电阻 

分 类 号：TM76[电气工程—电力系统及自动化]