柔性直流输电系统高频谐振阻尼特性分析及自适应抑制  

Damping Characteristic Analysis and Adaptive Suppression for High-frequency Resonance of Flexible DC Transmission System

作　　者：尹嘉豪 吕敬[1] 蔡旭[1] YIN Jiahao;LYU Jing;CAI Xu(Key Laboratory of Control of Power Transmission and Conversion,Ministry of Education(Shanghai Jiao Tong University),Shanghai 200240,China)

机构地区：[1]电力传输与功率变换控制教育部重点实验室(上海交通大学),上海市200240

出　　处：《电力系统自动化》2022年第22期90-100,共11页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(51907125)。

摘　　要：基于模块化多电平换流器(MMC)的柔性直流输电系统高频谐振现象频发,MMC的高频负阻尼特性是导致系统发生高频谐振的主要原因。文中首先采用谐波状态空间法建立了含解耦双同步参考坐标系锁相环(DDSRF-PLL)、正负序分离算法和正负序电流控制的MMC交流侧详细阻抗模型。然后,采用阻尼分析方法分析了MMC的高频阻尼特性,并提出参数阻尼灵敏度以定量提取影响MMC高频阻尼的关键因素。最后,提出了一种柔性直流系统高频谐振自适应抑制策略,并与2种典型高频谐振抑制策略进行比较,验证了所提策略在不同电网运行条件和不同MMC控制延时下的有效性。The high-frequency resonance phenomenon frequently happened in the flexible DC transmission system based on the modular multilevel converter(MMC).The high-frequency negative damping characteristic of MMC is the main reason for the highfrequency resonance of the system.Based on the harmonic state space method,this paper firstly establishes a detailed AC-side impedance model of MMC with consideration of decoupled double synchronous reference frame phase-locked loop(DDSRF-PLL),positive/negative sequence separation algorithm and positive/negative sequence current control.Then,the damping analysis method is used to analyze the high-frequency damping characteristics of MMC,and the parameter damping sensitivity is proposed to quantitatively extract the key factors which influence the high-frequency damping of MMC.Subsequently,an adaptive suppression strategy for high-frequency resonance of the flexible DC transmission system is proposed.The proposed strategy is compared with two typical high-frequency resonance suppression methods,which verifies the effectiveness of the proposed strategy under different grid operation conditions and different control delays of MMC.

关 键 词：柔性直流输电 模块化多电平换流器(MMC) 高频谐振 稳定性分析 负序控制 阻尼灵敏度 自适应抑制 谐波状态空间 阻抗模型 

分 类 号：TM721.1[电气工程—电力系统及自动化]