并联LC换相换流器拓扑、换相特性与控制策略  

Topology,Commutation Characteristics and Control Strategy of Shunt LC Commutated Converter

作　　者：王晨欣 夏嘉航 赵成勇 WANG Chenxin;XIA Jiahang;ZHAO Chengyong(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市昌平区102206

出　　处：《中国电机工程学报》2023年第14期5557-5568,共12页Proceedings of the CSEE

摘　　要：改进型并联电容换相换流器(evolutional shunt capacitor commutated converter,ESCCC)通过在交流母线侧投切电容,可以实现降低直流线路损耗的单位功率因数控制,但是存在交流线路电感较大、阀电压应力大等问题。针对此问题,提出一种并联LC换相换流器(shunt LC commutated converter,SLCCC)及其控制策略,可有效降低换流器占地面积,改善系统性能。建立拓扑结构和数学模型,分析其换相特性,通过多目标规划方法设计电感、电容等参数,并设计可实现有功、无功功率解耦的闭环控制策略。最后,在PSCAD/EMTDC环境中对参数设计和控制策略进行仿真验证,结果表明,新型换流器拓扑不仅可以降低换流器占地面积和直流线路损耗,提高抵御换相失败的能力,而且实现了闭环解耦单位功率因数控制。Evolutional shunt capacitor commutated converters(ESCCC)can achieve unity power factor control to reduce DC line loss by switching capacitors on the AC bus side,but they have problems such as large AC line inductance and large valve voltage stress.To solve these problems,a shunt LC commutated converter(SLCCC)and its control strategy are proposed in this paper,which can effectively reduce the footprint of the converter and improve the system performance.The topology and mathematical model are established,the commutation characteristics are analyzed,the parameters such as inductance and capacitance are designed through the multi-objective programming method,and the closed-loop control strategy that can realize the decoupling of active and reactive power is designed.Finally,the parameter design and control strategy are simulated and verified in PSCAD/EMTDC.The results show that the new topology can not only reduce the footprint of the converter and DC line loss and improve the ability to resist commutation failure,but also achieve decoupled closed-loop unity power factor control.

关 键 词：高压直流输电 单位功率因数 换相失败 并联LC支路 多目标规划 直流线路损耗 

分 类 号：TM73[电气工程—电力系统及自动化]