柔性交流输电系统(flexible AC transmission system,FACTS)的并网位置对电力系统的安全运行具有重要影响.本文综合考虑故障发生后的暂态与稳态过程,提出兼顾暂稳态判据的选址打分方法,在单机等面积定则基础上,推导出FACTS元件等值系统的暂态裕度量化积分,将暂态稳定裕度近似灵敏度和稳态母线电压越限危险度作为选址依据.基于FACTS元件与储能相结合技术,将有功死区控制、电池荷电状态限制和逆变器容量限制考虑进FACTS元件建模中,利用PSASP/UD自定义模块搭建具有储能作用的FACTS模型.通过电力系统分析软件 PSASP中CEPRI-36 节点系统进行仿真,在得分高的母线处采取FACTS元件以注入电流源形式并网参与系统紧急控制,验证本文所提选址方法的准确性及FACTS元件对抑制电力系统连锁故障扩散的影响.
A FACTS Location Method Considering Transient and Steady State Effects
The grid location of FACTS plays an important role in the safe operation of power system.This paper comprehensively considers the transient and steady-state processes after the fault occurs,and proposes a location scoring method taking into account the transient and steady-state criteria.Based on the single generator equal-area criterion,this paper derived the quantitative integral of transient margin of equivalent system considering FACTS elements and choose the transient stability margin approximate sensitivity and the steady-state bus voltage limit risk degree as the location basis.Based on the combination technology of FACTS elements and energy storage,the active dead time control,battery state of charge limit and inverter capacity limit are taken into account in the FACTS element modeling,and the FACTS model with energy storage is built by PSASP/UD custom module.Through the simulation of CEPRI-36 node system in power system analysis software PSASP,the FACTS element is connected to the grid in the form of injected current source at the bus with high score to participate in the emergency control of the system.It is used to verify the accuracy of the proposed location method and the influence of FACTS components on restraining the spread of cascading faults in power system.