计及海缆分布特性的海上风电柔直并网系统中高频谐振分析及抑制  

MID-AND HIGH-FREQUENCY RESONANCE ANALYSIS AND SUPPRESSION OF OFFSHORE WIND POWER GENERATION MMC-HVDC GRID-CONNECTED STSTEM CONSIDERING DISTRIBUTED CHARACTERISTICS OF SUBMARINE CABLE

作　　者：李辉[1] 李青和 姚然 谭宏涛 郑杰 杨微 Li Hui;Li Qinghe;Yao Ran;Tan Hongtao;Zheng Jie;Yang Wei(State Key Laboratory of Power Transmission Equipment&System Security and New Technology(Chongqing University),Chongqing 400044,China;CSIC Haizhuang Windpower Co.,Ltd.,Chongqing 401122,China)

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆400044 [2]中国船舶集团海装风电股份有限公司,重庆401122

出　　处：《太阳能学报》2023年第4期74-84,共11页Acta Energiae Solaris Sinica

基　　金：国家高技术船舶科研项目(MC-202025-S02)。

摘　　要：海上风电场交流海缆线路的分布电容特性易引发系统中高频谐振失稳,基于阻抗稳定性分析法,研究海上风电柔直并网系统的中高频谐振机理并提出相应的谐振抑制方法。首先,构建考虑海缆分布特性的并网系统小信号阻抗模型,并通过阻抗扫描进行验证。其次,基于阻抗稳定判据研究海缆分布特性及控制器参数等因素对并网系统中高频谐振特性的作用机理。最后,提出一种基于控制器参数优化的中高频谐振抑制方法,并通过仿真验证理论分析的正确性及抑制方法的可行性。结果表明,并网系统中高频振荡主要由交流海缆线路与交/直流装备之间的交互作用引起,长距离海缆分布特性会导致系统中高频呈现多谐振兼负阻尼特性,且柔直换流站的基频电流环比例系数过大时易降低系统中高频稳定性,可通过所提参数优化方法抑制系统中高频谐振。The distributed capacitive characteristics of AC submarine cable in offshore wind farm are prone to cause mid-and highfrequency resonance instability in the grid-connected system.Based on impedance stability analysis principle,the mechanism of resonance instability in the grid-connected offshore wind power generation modular multilevel converter(MMC)based HVDC system is studied and the corresponding resonance suppression method is proposed.Firstly,considering the distribution characteristics of submarine cable,the small-signal impedance model of grid-connected system is developed,which is validated by impedance scanning.Secondly,the impedance stability criterion is applied to investigate the influence of the distribution characteristics of submarine cable and the controller parameters on the mid-and high-frequency stability of system.Finally,a method is proposed to suppress the mid-and high-frequency resonance based on the optimization of controller parameters,and the accuracy of the theorectical analysis and the feasibility of the suppression method were verified by simulations.The results indicate that the mid-and high-frequency resonance in the grid-connected system are mainly induced by the interaction between the AC submarine cable and the AC/DC side equipment,and the distribution characteristics of the long-distance submarine cable will lead to multiple resonant peaks and negative damping in the system and deteriorate its stability,especially when the proportional coefficient of MMC fundamental frequency current loop is too large,which can be suppressed by the proposed parameter optimization method.

关 键 词：海上风电场 模块化多电平换流器 谐波谐振 分布特性 阻抗分析 参数优化 

分 类 号：TM614[电气工程—电力系统及自动化]