A Configuration Method of Reactive Power Compensation for 220kV Substations to Reduce Voltage Overshoot

In allusion to the difficulty of voltage regulation due to excessive compensation capacity of single compensator set and absence of inductive and dynamic reactive compensation in 220 kV substations,a synthetical reactive power compensation scheme for 220 kV substation,which combines discrete compensation with continuous compensation,is proposed.In the proposed scheme,the compensation system is composed of one set of direct static synchronous compensator(STATCOM) and shunt capacitor banks which can be flexibly switched.Firstly,an evaluation model for reactive power compensation and votlage regulation in 220 kV substation and its evaluation index called reactive power overshoot rate are constructed and such an index reflects the contradiction between finite number of reactive power compensator sets and inadvisability of excessive compensation capacity of single compensator set,thus the proposed compensation configuration scheme becomes a fundamental way to improve the accuracy of steady-state voltage control and reduce the overshoot to ensure transient voltage stability at receiving end.Simulation results of a certain regional power network in Guangdong province show that the proposed method is favorable to steady-state voltage stability control of power network and can provide effective dynamic voltage support under emergency condition.