Application of Bacterial Foraging Algorithm for Optimal Location of FACTS Devices with Multi-Objective Functions

摘要

The continuous demand in electric power system network has caused the system to be heavily loaded leading to voltage instability. Voltage instability condition in a stressed power system could be improved by controlling the reactive power dispatch, reactive power injection on the load bus and controlling the tap changing of on- load-tap-changer (OLTC) transformer. This paper presents an application of Bacterial Foraging (BF) Algorithm to find optimal location of Flexible AC Transmission System (FACTS) devices to achieve voltage stability improvement in power system with minimum cost of installation of FACTS devices. While finding the optimal location, thermal limit for the lines and voltage limit for the buses are taken as constraints. Three types of FACTS devices, Thyristor Controlled Series Compensator (TCSC), Static VAR Compensator (SVC) and Unified Power Flow Controller (UPFC) are considered. The proposed approach has been evaluated with four different objective functions namely, loss minimization, voltage profile improvement, voltage stability enhancement and total cost minimization. Voltage stability level of the system is defined based on the L-index of load buses. The IEEE 14 and IEEE 30- bus systems were used as test systems to demonstrate the applicability and efficiency of the proposed method. The results are encouraging and will be useful in voltage stability improvement.