柔性直流接入电网后的高频谐振及其抑制策略  

High-frequency Resonance and Its Suppression Strategy of Power Grid with Flexible DC Transmission System Connected

作　　者：周竞宇[1] 赵玲 张军 刘汉军 ZHOU Jingyu;ZHAO Ling;ZHANG Jun;LIU Hanjun(CSG EHV Power Transmission Company,Guangzhou 510620,China;TBEA China Xinjiang Sunoasis Co.,Ltd.,Xi'an 710000,China)

机构地区：[1]中国南方电网超高压输电公司,广州510620 [2]特变电工新疆新能源股份有限公司,西安710000

出　　处：《浙江电力》2021年第8期1-6,共6页Zhejiang Electric Power

摘　　要：受控制链路延时的影响,基于MMC(模块化多电平换流器)的柔性直流输电系统接入电网后可能发生高频谐振现象。对此,在dq坐标下建立了包含控制系统在内的柔性直流系统高频阻抗模型和交流系统等效模型,分析了柔性直流系统高频谐振机理。在此基础上,提出基于准谐振控制的柔性直流输电系统高频谐振抑制策略,给出了准谐振控制器R的参数设计方法,最后通过电磁暂态仿真验证了所提控制策略的正确性、可行性。Flexible DC transmission system based on MMC(modular multilevel converter),after integrated into the power grid,may lead to high-frequency resonance due to control link delay.This paper establishes a high-frequency impedance model of flexible DC system with control system and an equivalent model of AC system and analyzes the generation mechanism of high-frequency resonance of flexible DC system.On this basis,a high-frequency resonance suppression strategy based on quasi-resonance control is proposed,and a parameter design method of the quasi-resonance controller is designed.Finally,the correctness and feasibility of the proposed strategy are verified by electromagnetic transient simulation.

关 键 词：模块化多电平换流器 阻抗模型 高频谐振 准谐振控制 

分 类 号：TM721.1[电气工程—电力系统及自动化]