An optimised design of controller for UPFC to improve the transient stability performance in power system

In the present scenario, due to the growing of energy demand it is necessary to maintain system stability. For this reason, various equipments based on the power electronics have been developed under the name of Flexible Alternating Current Transmission Systems (FACTS) devices; which are used in the last couple of years. Among all the facts devices Unified Power Flow Controller (UPFC) is the most versatile one in regard to control the power flow and to improve the transient stability of a system. The modelling of the controller plays a major role in the performance of the UPFC. The performance of UPFC for different mode of operation using PI controller is being studied. In this paper, a detailed comparative analysis is done, by taking performance criteria of UPFC controller into consideration, for optimal tuning of PI controller through various optimization techniques. By taking the settling time as the reference the performance is compared with Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Cuckoo Search Optimization (CSO) which are so called population optimisation techniques, used for optimal tuning of PI controller. The UPFC is modelled in our user friendly software MATLAB/M-file environment.