计及UPFC的含新能源电网静态电压稳定性分析

Static voltage stability analysis of power grid with new energy considering UPFC

随着大规模高比例新能源的接入,新型电力系统的安全运行面临静态电压稳定性的问题。文章提出使用统一潮流控制器(Unified Power Flow Controller,UPFC)提升新能源电网静态电压稳定性的方案,从系统静态电压稳定性方面评估UPFC发挥的控制效能。首先详细分析了UPFC的结构及工作原理,并基于UPFC的等效功率注入模型得到电力系统潮流计算方程;其次基于潮流计算方程提出反映系统静态电压稳定的效能评估指标,计算分析接入不同容量新能源对系统静态电压的影响以及UPFC对系统薄弱节点静态电压的提升;最后通过仿真验证,安装UPFC后能明显地改善新能源电网薄弱节点的电压稳定问题。文中所提出的方法方便快捷,具有一定的实际应用价值。

With the large-scale and high-proportion of new energy access,the safe operation of new power system is faced with the problem of static voltage instability.In this paper,the Unified Power Flow Controller(UPFC)is proposed to improve the static voltage stability of the new energy grid,and the control efficiency of UPFC is evaluated from the static voltage stability of the system.Firstly,the structure and working principle of UPFC are analyzed in detail,and the power flow calculation equation based on the equivalent power injection model of UPFC is obtained.Secondly,the efficiency evaluation index reflecting the system static voltage stability is proposed based on the power flow calculation equation,the influence of new energy with different capacity on the static voltage of the system and the increase of the static voltage of the weak node of the system by UPFC are calculated and analyzed,the installation of UPFC can obviously improve the voltage stability of weak nodes in the new energy grid.The method presented in this paper has the characteristics of convenience and rapidness,and has certain practical application value.