摘要
针对海上风电经MMC-HVDC并网系统岸上交流故障造成的直流过电压问题,提出一种利用海上换流站储能裕度吸收盈余功率和风电机组降低输出功率的协调控制策略。在故障期间,海上换流站采用能量控制,使其子模块电容吸收盈余功率,同时根据其当前能量的变化,抬升风电场交流电网频率,使得风电机组网侧变流器根据频率偏差协同限制注入柔性直流系统的功率,从而实现无需通信系统的直流过电压抑制。最后通过仿真验证了所提方法的有效性。
Aimed at the DC overvoltage problem caused by the onshore AC fault in an MMC-HVDC grid-connected sys⁃tem for offshore wind power,a coordinated control strategy is proposed to absorb the surplus power by utilizing the ener⁃gy storage margin of offshore converter stations and reduce the output power of wind turbines.During the fault period,the offshore converter station adopts energy control to make the sub-module capacitor absorb the surplus power.At the same time,according to the energy changes at the offshore converter station,the AC grid frequency of the wind farm is raised,so that the grid-side converter can coordinately limit the power injection to the flexible DC system according to the frequency deviation.As a result,the DC overvoltage suppression is realized without any communication systems.Fi⁃nally,the effectiveness of the proposed method is verified by simulations.
作者
赵平
倪世杰
黄宇昕
贾浩森
李振兴
ZHAO Ping;NI Shijie;HUANG Yuxin;JIA Haosen;LI Zhenxing(College of Electrical Engineering and New Energy,China Three Gorges University,Yichang 443002,China;Hubei Provincial Key Laboratory for Operation and Control of Cascaded Hydropower Station(China Three Gorges University),Yichang 443002,China)
出处
《电力系统及其自动化学报》
CSCD
北大核心
2023年第8期62-70,共9页
Proceedings of the CSU-EPSA
基金
国家自然科学基金资助项目(52077120)
强电磁工程与新技术国家重点实验室开放课题资助项目(AEET 2022KF002)。
关键词
柔性直流输电系统
交流故障
盈余功率
能量控制
风电机组
协调控制
flexible DC transmission system
AC fault
surplus power
energy control
wind turbine
coordinated control
