计及短路比提升与暂态过电压抑制的含高比例风电送端电网两阶段式调相机优化配置

Two-stage Optimal Configuration of Condenser for High-proportion Wind Power Sending-end Power Grid Considering Short Circuit Ratio Increase and Transient Overvoltage Suppression

随着送端电网中大规模风电机组的接入及常规同步机组的置换淘汰,电网短路比水平下降,电压支撑能力削弱,故障时易导致新能源机组暂态过电压而发生脱网事故。面向含高比例风电的送端电网,研究综合计及短路比提升和暂态过电压抑制的调相机优化配置方法。首先,利用新能源多场站短路比(multiple renewable energy stations’short-circuit ratio,MRSCR)分析了调相机接入对风电场短路比的提升作用,并基于调相机暂态快速无功响应特性揭示了其对风电机组暂态过电压的抑制机理;然后,提出一种同时计及短路比提升和暂态过电压抑制的两阶段式调相机优化配置策略,第一阶段以风电场短路比提升为核心约束优化配置调相机位置与基础容量,第二阶段以暂态过电压安全为关键约束进行调相机配置容量修正,并引入量子遗传算法(quantum genetic algorithm,QGA)进行优化求解。最终,基于PSD-BPA在含高比例风电的送端电网进行算例分析,验证了所提出的调相机优化配置方法能够显著提升风电机组多场站短路比水平并有效抑制风电机端暂态过电压。

With the connection of large-scale wind turbines and the replacement of conventional synchronous generators in a sending-end power grid,the short circuit ratio level of the grid decreases,and the voltage support ability is weakened.A fault can easily result in transient overvoltage of new energy generators and cause off-grid accidents.This paper studies the optimal configuration method of synchronous condenser for the sending-end power system with a high renewable penetration level,considering the short-circuit ratio improvement and transient overvoltage suppression.Firstly,the condenser's access improvement effect on the wind farm's short-circuit ratio is analyzed using the multiple renewable energy stations'short-circuit ratio(MRSCR).Based on the condenser's fast reactive power response characteristics,its influence on the transient overvoltage of the wind turbine is revealed.Then,a two-stage optimal configuration strategy for the condenser is proposed to consider both short-circuit ratio improvement and transient overvoltage suppression.In the first stage,the core constraint of wind farm short-circuit ratio improvement is considered to optimize the position and basic capacity of the condenser.In the second stage,the obtained capacity is corrected based on the key constraint of transient overvoltage safety,and the quantum genetic algorithm(QGA)is introduced to optimize the solution.Finally,based on the analysis of PSD-BPA in a sending-end power grid with a high proportion of wind power,it is verified that the proposed condenser configuration method can significantly improve the MRSCR and effectively suppress the transient overvoltage of wind turbines.