摘要
交流电网发生故障扰动时,基于VSC-HVDC联网的风电场并网系统应具有一定的故障穿越能力。本文分析了基于VSC-HVDC的风电场并网系统的稳态控制策略及运行特性,对于交流电网发生故障扰动的情况,提出了一种基于风电机组惯性支持的故障穿越方法。该方法根据VSC-HVDC直流电压的波动量,调节风电场出口的频率,使风机输入的机械功率暂时以发电机转子动能的形式储存,从而减少了风电场输出的电磁功率,提高了系统的故障穿越能力。通过对由不同类型的风电机组组成的风电场经VSC-HVDC并网的系统进行仿真分析,证明了该方法能够在电网电压跌落后快速响应,防止VSC-HVDC直流过电压,提高了系统的故障穿越能力。
Wind farm integrated with VSC-HVDC should have fault ride through(FRT) capability when the AC grid fault. This paper analyzes the steady-state control strategy and the voltage-current characteristic of the VSC-HVDC used for wind farm integration, and then purposed a novel FRT strategy based on the analysis of wind turbines.The proposed method adjusts the wind farm frequency according to the fluctuations of the VSC-HVDC DC voltage, and the input mechanical power is temporarily stored in the form of generator rotor kinetic energy, thereby reducing the wind farm output electromagnetic power so as to keep the system power balanced. This FRT control strategy is analyzed by the simulation studies using MATLAB/Simulink and the simulation results show that the proposed strategy can respond quickly in the sudden voltage dip of the grid to prevent DC over-voltage, which imoroves the fault ride through caoabilitv of the system.
出处
《电工技术学报》
EI
CSCD
北大核心
2013年第12期150-159,共10页
Transactions of China Electrotechnical Society
基金
国家自然科学基金资助项目(50977028
51277072)