Fuzzy logic control scheme with variable gain for static VAr compensator to enhance power system stability

This paper presents a fuzzy logic (FL) control scheme with variable gain for static VAr compensators (SVC) to enhance power system stability. The proposed control scheme is simple and has low computational requirements, therefore, it is suitable for online implementation using a microcomputer. To control the SVC, only the real power flow signal is utilized at the location of the SVC. Variable gain is proposed to terminate the switching control of the SVC soon after reaching quasi steady-state to avoid excessive and unnecessary control action from the SVC. Coordination with power system stabilizers (PSS) is also considered for further enhancement of stability. The performed simulation studies demonstrate the effectiveness of the proposed control scheme.