双半桥与并联全桥子模块混合MMC均压与直流故障控制研究  

Research on Control Method of Voltage Balance and DC Fault Clearance of Hybrid MMC Composed of D-HBSM and P-FBSM

作　　者：石璐[1] 李嘉龙 赵成勇[1] 许建中[1] 贾秀芳[1] SHI Lu;LI Jialong;ZHA;XU Jianzhong;JIA Xiufang(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)

出　　处：《中国电机工程学报》2018年第21期6411-6419,共9页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51607065)~~

摘　　要：子模块混合型模块化多电平换流器高压直流输电（modular multilevel converter HVDC,MMC-HVDC）兼具直流故障穿越能力和较好的经济性,然而当子模块数目众多时,面临控制器排序均压计算量大和传感器实时性要求高等问题。该文针对由双半桥子模块和并联全桥子模块构成的新型混合MMC,分析其并联均压特性,在此基础上提出新型混合MMC的阀段间和阀段内均压控制策略;通过分析子模块闭锁特性,设计直流故障控制策略。在PSCAD/EMTDC中的电磁暂态仿真结果表明,采用所提均压控制策略可在有效降低对控制器性能和传感器精度要求的前提下,实现新型混合MMC子模块电容电压全局良好均衡,并验证了直流故障穿越控制策略的有效性。Hybrid modular multilevel converter HVDC （MMC-HVDC） combines DC fault ride-through capability with good economy. However, as the number of sub-modules is quite large, it is faced with issues about more computational boards and voltage sensors for sub-module voltage balancing at each limited control cycle. A novel hybrid MMC consisting of double half-bridge sub-module （D-HBSM） and paralleled full bridge sub-module （P-FBSM） was produced and its parallel voltage-balancing characteristics were analyzed. On the basis of this, it is proposed that the sub-module capacitor voltage balancing control method between and within the converter valve sections. Furthermore, based on the analysis of sub-module blocking characteristics, DC fault control strategy was designed. Finally, the results of electromagnetic transient simulation in PSCAD/EMTDC show that, under the premise of effectively reducing the controller performance and sensor accuracy, the overall voltage balance of the novel hybrid MMC can be achieved by the proposed voltage balancing control method. The effectiveness of DC fault ride-through control strategy was also verified.

关 键 词：混合模块化多电平换流器 双半桥子模块 并联全桥子模块 电容电压均衡 直流故障穿越 

分 类 号：TM72[电气工程—电力系统及自动化]