Research On Control Strategy And Application Of Relocatable Static Var Compensator

In order to increase the means and the ability of reactive powerregulation of Fujian power system, especially,Quanzhou city powersystem is a heavy load area which is short of power source to supportit.,this paper proposes that using dynamic reactive power compensationdevices like Static Var Compensator(SVC) may play an important role insolving this problem. Furthermore, with rapid development of Fujianpower system construction, the system needs some Relocatable Static VarCompensators（RSVC） in the whole demands of SVCS. Based on thedeeply comprehending of RSVC, the following aspects are deeplyanalyzed in this paper.Based on the comprehensive expatiation of the working principle andoperating characteristic of Thyristor Controlled Reactor (TCR) andThyristor Switched Capacitor(TSC),and the advantage of RSVC comparedto SVC,this paper dissertates that it is feasible to apply TCR-TSC typeRSVC in220kV transformer substation of Guifeng in Quanzhou area.Through this demonstrative project,this paper studies on the controlstrategy and the application of RSVC in Fujian power system. It will setup an example for future.Research on the control strategy: Firstly, study on the strategy ofTCR-TSC coordinate control based on PSCAD/EMTDC. The simulationsshow that TSC adjusts roughly, and TCR fine-tunes for the phased whenthe system is in the transient process, and the two should be wellcoordinated control with each other,thus it can realize smooth andcontinuous adjustment of reactive power. Moreover, to contrast controlobjective between10kV bus voltage and220kV bus voltage,the resultshows10kV bus voltage for the control objective can be moreaccurate,and responses quickly.Secondly,building up the models of SVC with or withoutsupplementary control (power-swing damping control-PSDC)based on BPA and PSASP,then studying on the SVC with supplementary controlinhibit low frequency oscillation. The simulations demonstrate that theSVC with supplementary control can improve system damping throughsmall disturbance and large perturbation.Research on the application:Study on the SVC which may improvethe power quality of Fujian power system through a lot of simulationsbased on BPA.It also analyzes the dynamic compensation effect of SVCmainly through three aspects:steady-state voltage regulation,220kV and500kV line faults and load fluctuation. The simulations show that SVCresponses quickly,changes rapidly its emitted reactive power, speeds uprestoration of transient voltage. Thereby SVC can provide dynamicreactive power supply for power system.In summary,if we make a futher study on the strategy of TCR-TSCtype RSVC’s control and extend the RSVC to the field of Fujian powersystem,it will improve the stability of Fujian power system,and alsoimprove the transportation ability of the power network.