摘要
海上直驱风电经柔性直流输电并网系统由多变流器构成,具有不同时间尺度的控制回路和复杂的动态特性.基于双风电场经柔性直流并网系统算例,采用状态空间分析法研究系统次/超同步振荡模态与电流控制回路的关联关系.研究表明,系统存在3种与变流器电流环相关的主导振荡模态,分别对应于风场-柔直模态、风场间模态以及柔直-交流系统模态,风场侧的模态与柔直-交流系统模态是解耦的,相关变流器控制参数、系统的运行工况对3种模态稳定性具有重要影响;单个主导模态失稳引起的振荡会波及到柔直的另一端,需要甄别引起振荡的根本原因,以利于针对性设计抑制策略.研究结果对于认识海上风电经柔直并网系统动态特性、参数设计以及振荡抑制具有指导作用.
The system of offshore direct-drive wind farm connected to the power grid via voltage source converter based high voltage direct current(VSC-HVDC)transmission consists of several converters,which have different time scale control loops and complex dynamic characteristics.Based on an example case with two direct-drive wind farms and VSC-HVDC transmission system,the sub/super-synchronous oscillation modes of the system and its relationship with current control loops are studied by state space analysis.The research shows that there are three dominant modes related to the current control of the converter in the system,which are the oscillation mode between wind farms and the offshore converter station,the mode between the offshore wind farms,and the mode between the onshore converter station and the alternating current(AC)system.The modes at the wind farm side are decoupled from the mode between the onshore converter station and the AC system.The relevant control parameters of the converters and the operating conditions have an important impact on the stability of the three modes.The oscillation caused by the single dominant mode may spread to the other side of VSC-HVDC,which means it is necessary to identify the root cause of oscillation in order to design the suppression strategy.The research results is of guidance to the understanding of the dynamic characteristics of offshore wind power grid-connected systems via VSC-HVDC,parameter design,and oscillation suppression.
作者
张志强
李秋彤
余浩
陈鸿琳
孙海顺
ZHANG Zhiqiang;LI Qiutong;YU Hao;CHEN Honglin;SUN Haishun(Grid Planning and Research Center,Guangdong Power Grid Co.,Ltd.,Guangzhou 510080,China;School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2022年第12期1572-1583,共12页
Journal of Shanghai Jiaotong University
基金
南方电网电力规划专题项目(031000QQ00200003)。
关键词
海上风电
柔性直流
状态空间分析法
次/超同步振荡
offshore wind power
voltage source converter based high voltage direct current(VSC-HVDC)transmission
state space analysis
sub/super-synchronous oscillation
