Optimal Location of UPFC by Using Modified Particle Swarm Optimization for Voltage Stability

Abstract

Voltage security is a crucial issue in power systems especially under heavily loaded condition. In the new scheme of restructuring, voltage stability problem becomes even more serious. In order to solve the kind of thorny problem, experts employ various methods for relieving congested difficulties. There are many new power-electronics-based devices using to solve the difficult problems recently. Unified Power Flow Controller (UPFC) is the most powerful device of these devices. A new model is proposed in this thesis to improve existing power-based model by using the Norton Equivalent Theorem. The proposed model can be integrated with the Equivalent Current Injection (ECI) power flow model easily. By ECI algorithm, it is much quickly and precisely to implement power flow calculations. By making use of modified particle swarm optimization (MPSO), the optimal location of UPFC in power system will be obtained. Finally simulation shows the optimal location and capacity of new UPFC with ECI model to enhance power system voltage stability by using MPSO. The proposed method demonstrates the improvement of voltage stability margin.