一种MMC-HVDC的直流电压波动抑制新方法  

A New Approach for Suppressing DC Voltage Ripples of MMC-HVDC

作　　者：周月宾[1] 江道灼[1] 胡鹏飞[1] 梁一桥[1] 郭捷[1] 林志勇[1] 

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027

出　　处：《中国电机工程学报》2013年第27期36-43,7,共8页Proceedings of the CSEE

基　　金：浙江省重点科技创新团队(2010R50004)~~

摘　　要：针对柔性直流输电系统常规直流电压波动抑制算法中存在的缺陷,提出一种适用于模块化多电平换流器型高压直流输电系统(modular multilevel converter based high voltage direct current,MMC-HVDC)的直流电压波动抑制方法。该方法利用MMC特有的"储能"特性,在交流系统不对称时,控制MMC交、直流侧瞬时有功功率不再平衡,从而实现MMC交流侧电流依然保持对称运行,同时直流侧电压、电流和功率保持为恒定。为了实现上述控制功能与目标,建立三相交流系统不对称时MMC直流回路的模型,设计0坐标系下以比例谐振调节器为基础的控制策略,且探讨MMC-HVDC中的协调控制问题。最后,搭建71电平背靠背MMC-HVDC系统模型进行数字仿真,结果验证了所提控制方法的有效性。Since the common solution for eliminating DC voltage tipples in voltage sourced converter based high voltage direct current （VSC-HVDC） transmission system has some drawbacks, this paper proposed a new method applied to modular multilevel converter based high voltage direct current （MMC-HVDC）. The method uses the sub-module energy storage capability in MMC, making the instantaneous active power between ac and dc side of MMC unequal under unbalanced AC system. Meanwhile, this method keeps the ac current balanced, and eliminates the DC voltage, DC current and DC power ripples as well. To fulfill such a control goal, according to the dc-loop model of MMC, a controller in aflO frame based on proportional resonant regulator was designed, and then the coordinated control strategy was discussed in case of MMC-HVDC. Finally, a back-to-back MMC-HVDC simulation model with 71 levels was built to verify the proposed controller. The results show that the controller works well under both balanced and unbalanced AC system.

关 键 词：模块化多电平换流器 直流输电 交流系统不对称直流电压波动 比例谐振调节器 

分 类 号：TM85[电气工程—高电压与绝缘技术]