华东沿海风电场群电网主动频率支撑策略

An Active Frequency Support Strategy for Costal Wind Farms in East China

针对华东电网多种运行方式场景下暂态频率响应的特性,提出沿海风电场经交/直流并网的主动频率支撑的自同步电压源控制策略;在此基础上,通过基于PSCAD/EMTDC的华东电网电磁暂态等值模型,给出华东电网在不同新能源占比下的风电场电网支撑能力的要求,以及与常规同步机协同惯量响应的基本规则。仿真结果表明,华东电网在新能源占比高于30%后,风电的惯量响应对电网频率最低点的提升作用明显,随着沿海风电场群容量的快速增长,风电机组提供主动惯量支撑不可或缺;风电机组的虚拟惯性时间常数宜设置在风电机组的物理惯性时间常数附近,在需要参与系统一次调频时,应将风机变桨系统和同步机一次调频的控制进行协同优化才可避免由此产生的频率振荡。

According to the characteristics of transient frequency response of the East China Power Grid under various operation modes,an active frequency support strategy is proposed for coastal wind farms.Through the PSCAD/EMTDC-based electromagnetic transient equivalent model of the East China Power grid,the requirements of the East China power grid on the support capacity of wind farms under different penetration of renewable energy,and the basic rules of collaborative inertia response with conventional synchronous generators are given.The simulation results show that when the penetration of renewable energy in the East China Grid is higher than 30%,the inertia response of wind power plays an obvious role in increasing the frequency nadir of the grid,and with the rapid growth of the capacity of coastal wind farms,it is indispensable for wind turbines to provide active inertia support;the virtual inertia time constant of wind turbines should be set around the physical inertia time constant of the wind turbines;when wind turbines are needed to participate in the primary frequency regulation(PFR),the pitch system control of wind turbines and the PFR control of synchronous generators should be co-optimized to avoid frequency oscillation.This article can provide a useful reference for the power grid operation under high penetration of non-synchronous power sources.