±800kV酒泉—湖南特高压直流工程无功补偿优化配置方案

Reactive Power Configuration Scheme of ± 800 kV Jiuquan-Hunan UHVDC Project

±800 kV酒泉—湖南特高压直流工程将大规模的风电功率送到具有典型输入电源特征的湖南电网,因此,无功补偿配置不仅需要考虑直流系统的无功需求,还应针对该工程送受端接入的交流电网无功电压支撑能力较弱的问题通过合理加装动态无功补偿设备优化无功配置。结合酒泉换流站接入的交流电网有大规模风电的特性,提出了在换流站站用变低压侧加装静止无功补偿器(static var compensator,SVC)无功补偿方案,并确定加装SVC后换流站的小组滤波器容量。针对湖南换流站接入的交流系统面临的低电压风险,在湖南换流站站用变低压侧配置静止同步补偿器(static synchronous compensator,STATCOM),并优化配置相应的小组滤波器容量。经分析和校核,在换流站配置动态无功补偿设备,能够提高换流站近区交流电网的电压稳定性,减小滤波器投切带来的换流母线电压波动,并降低设备投资。

± 800 kV Jiuquan-Hunan UHVDC project sends large scale wind power to Hunan power system which is depending on the outside power source. Thus its reactive power compensation configurations not only need to consider the reactive power requirements of the DC system, but also should be optimized through equipped with reasonable dynamic reactive power compensation devices, according to weak reactive voltage supporting ability of AC grid in transmitter/receiver system. Because the AC grid connected to Jiuquan had large-scale wind power, the reactive power configuration scheme was proposed, in which static var compensator （SVC） was applied in the low-voltage side of substation-used transformer in converter station, and the filter capacity of converter station with SVC was determined. Aiming at low voltage risk of AC system connected to Hunan converter station, static synchronous compensator （STATCOM） was applied in the low-voltage side of substation-used transformer in Hunan converter station, the corresponding filter capacity was optimized and configured. Based on the calculation and analysis, it can be concluded that the dynamic reactive power compensation device applied in converter station can improve the voltage stability of the connecting AC system nearby converter station, reduce the voltage fluctuation of the converter bus caused by filter switching, and decrease the device investment.