Performance analysis of UPFC in healthy and weak locations of power system network

This paper aims at determining the most suitable zone for the connection of UPFC in a transmission system. Using voltage stability index (VSI), the healthy and weak zones of power system are identified. One UPFC with the same compensation is placed in both healthy and weak zone separately. User friendly Mi-power 9.1 software is applied for real-time simulation with practical security constraints of the power system. IEEE 57-bus system with arbitrarily increased load is considered as a test case. The performance of UPFC is judged by voltage stability enhancement index (VSEI) and reduction of active, reactive power losses and relative environmental pollution deterioration index (REPDI). The test results are compared for all the cases and it reveals that the placement of UPFC in weak zone is the most suitable considering all performance indices.