Genetic algorithm optimised fuzzy control of DSTATCOM for improving power quality

Proportional and Integral (PI) controllers are often used to control the operation of the Distribution Static Compensator (DSTATCOM) for the distribution power system. However, since the power system is highly nonlinear and subject to various disturbances, the PI controlled DSTATCOM cannot provide optimal performance for different operating points. More robust controllers such as the ones based on fuzzy logic approach are required for the DSTATCOM to provide adequate dynamic voltage control and to improve power quality and stability of the distribution power system. This paper presents the design of Fuzzy Logic Controllers (FLC) of a DSTATCOM for improving power quality for a distribution power system. The scaling factors of the designed FLC are optimised using Genetic Algorithms (GA). The GA optimised FLC for the DSTATCOM used for improving power quality and dynamic performance of a distribution power system is compared with a DSTATCOM controlled by PI controllers. The performances of the DSTATCOM controllers are evaluated during grid-side voltage and large load variations of the distribution power system. Simulation results show that the DSTATCOM with the GA optimised FLC can improve the power quality and dynamic performance of distribution power system and provide better system dynamic performance than the DSTATCOM with the conventional PI controllers.