Study on adaptive PI controller of distribution static synchronous compensator

For improving the voltage stability in power system, a control scheme is proposed for distribution static synchronous compensator (DSTATCOM) on the basis of traditional PI and fuzzy controller, which is formed into an adaptive fuzzy PI controller. In this paper, the fundamental principle and topology of DSTATCOM are analyzed at first. Considering direct control by active power, two methods applied PI control and adaptive fuzzy control individually are used to balance the dc-link voltage of capacitors. It is shown from the simulation results that algorithm with the adaptive fuzzy control is preferred in response time and compensated accuracy. Meanwhile, better transient performance without overshoot or oscillation is achieved from the results, which has proved the strong robustness of the method.