柔性直流输电系统高频振荡抑制策略研究  

Research on the Suppression Strategy of High-frequency Resonance for MMC-HVDC

作　　者：侯延琦 刘崇茹 王宇 孔玮 HOU Yanqi;LIU Chongru;WANG Yu;KONG Wei(State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,China;State Grid Corporation of China,Xicheng District,Beijing 100031,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 [2]国家电网有限公司,北京市西城区100031

出　　处：《中国电机工程学报》2021年第11期3741-3750,共10页Proceedings of the CSEE

基　　金：国家电网公司科技项目(SGTYHT/17-JS-199)。

摘　　要：基于模块化多电平换流器(modular multilevel convert,MMC)的柔性直流输电系统的长控制链路延时使柔性直流系统高频阻抗呈现负阻尼特性,易与交流输电线路分布参数相互作用造成高频振荡现象。该文根据电流内环控制建立换流器高频阻抗简化模型,从原理上分析附加阻尼控制环节对抑制系统高频振荡现象的局限性;其次,分析用于高频振荡抑制的无源滤波装置的外特性要求,提出并联RLC高通滤波装置的振荡抑制方案以及滤波装置参数设计方法,能够适应系统工况改变,并有效控制损耗;最后,基于实际工程仿真试验验证理论分析的正确性和所提方法的有效性。The long control link delay of the flexible DC transmission system based on modular multilevel converter makes the high-frequency impedance of the system present negative damping characteristics, which is easy to interact with the distributed parameters of the AC lines and cause the high-frequency resonance of the system. At first, this paper established the simplified model of high frequency impedance of MMC based on the current inner loop control strategy, and analyzed the limitations of additional damping control strategy on suppressing high-frequency resonance in principle.Secondly, this paper analyzed the output characteristic requirements of passive filter that used to suppress high-frequency resonance, and proposed a method of high-frequency resonance suppression based on parallel second-order high-pass RLC filter and a parameter design method for it, which can adapt to the change of system condition and effectively limit the loss. Finally, the correctness of the theoretical analysis and the effectiveness of the proposed method were verified based on the simulation of practical project.

关 键 词：模块化多电平换流器 高频振荡 附加阻尼控制 无源滤波装置 

分 类 号：TM721[电气工程—电力系统及自动化]