Comparative Study between Basic Control and Supplementary Control of STATCOM

As an important component of Flexible AC Transmission Systems(FACTS),STATCOM is the main direction for the development of reactive power compensation.The research of its basic control methods has great significance.Firstly,PSCAD/EMTDC software was applied to simulate and compare the two basic control strategies of STATCOM: constant voltage control and constant reactive power control.In order to reduce the fluctuations of DC side voltage,supplementary DC side voltage control was added to the basic control and achieved good results.Finally,this research analyzed the effect of constant reactive power control strategy with DC side voltage control when high compensation was applied.The results indicate the advantage of constant reactive power control strategy for improving the transient stability of power system.