弱电网下MMC高低压穿越的综合运行控制技术  

Integrated operation control technology of MMC high and low voltage ride-through under weak grid

作　　者：马文忠[1] 孙沐紫 王玉生[2] 张文艳[1] 李恒硕 朱亚恒 MA Wenzhong;SUN Muzi;WANG Yusheng;ZHANG Wenyan;LI Hengshuo;ZHU Yaheng(College of New Energy,China University of Petroleum(East China),Qingdao 266580,China;PetroChina Planning&Engineering Institute,Beijing 100083,China)

机构地区：[1]中国石油大学(华东)新能源学院,山东青岛266580 [2]中国石油天然气股份有限公司规划总院,北京100083

出　　处：《电力工程技术》2025年第2期123-133,共11页Electric Power Engineering Technology

基　　金：山东省自然科学基金资助项目(ZR2022QE285)。

摘　　要：针对模块化多电平换流器(modular multilevel converter,MMC)在弱电网下高低压故障穿越问题,文中提出包含整体、相间、上下桥臂均压和改进锁相环(phase-locked loop,PLL)、多谐振控制的多环节控制策略。首先,改进双二阶广义积分器(double second-order-generalized integrator,DSOGI)的前置滤波环节并在PLL中采用非线性比例积分(proportional integral,PI)控制;其次,基于功率再分配提出弱电网下MMC的电容电压均衡控制方法,通过控制桥臂电流中的直流成分,实现子模块有功功率的再分配;然后,考虑上、下桥臂损耗不一致或参数不对称的工况,采用上、下桥臂有功功率再分配的方法改进传统的上、下桥臂均压控制。仿真结果表明,所提控制策略能够实现系统的故障穿越不间断运行,解决高低压穿越时PLL检测相位和频率不准确的问题以及三相电压不平衡导致的电流不平衡问题。In order to solve the problem of high and low voltage fault ride-through of modular multilevel converter(MMC)under weak grid,a multi-link control strategy including capacitance voltage balancing control of integral,phase-to-phase and upper and lower bridge arm,improved phase-locked loop(PLL)and multi-resonance control is proposed.Firstly,the prefiltering stage of the double second-order generalized integrator(DSOGI)is improved,and nonlinear proportional integral(PI)control is adopted in the PLL.Secondly,a capacitance voltage equalization control method based on the power redistribution for MMC under weak grid is proposed,and the active power redistribution of the submodule is realized by controlling the DC component of the bridge arm current.Then,considering the inconsistency of the upper and lower arm losses or asymmetrical parameters,the traditional voltage equalization control of the upper and lower bridge arm is improved by adopting the method of the active power redistribution of the upper and lower bridge arm.The simulation results show that the proposed control strategy realizes the uninterrupted operation of the system under the fault ride-through,solving the problem of inaccurate phase and frequency detection of PLL during high and low voltage ride-through and the current imbalance caused by three-phase voltage imbalance.

关 键 词：模块化多电平换流器(MMC) 高电压穿越 低电压穿越 电容电压均衡 双二阶广义积分器(DSOGI) 弱电网 

分 类 号：TM721[电气工程—电力系统及自动化]