Real-time performance analysis and comparison of various control schemes for particle swarm optimization-based shunt active power filters

Abstract

Selection of proper reference compensation current extraction scheme plays the most crucial role in the performance of an active power filter (APF). This paper mainly describes three different control schemes used in APFs namely, Conventional instantaneous active and reactive power (p–q), Modified p–q, and Instantaneous active and reactive current component (id–iq) schemes. Our objective here is to bring down the total harmonic distortion (THD) of source current sufficiently below 5% at the point of common-coupling (PCC), in order to satisfy the IEEE 519-1992 Standard recommendations on harmonic limits. Comparative evaluation of the three control schemes shows that, id–iq method is the best control scheme to be implemented on shunt APFs, irrespective of the supply voltage conditions, even under sudden load fluctuations. Results have been validated using MATLAB/Simulink simulations followed by real-time performance verification in Opal-RT Lab simulator. Here, the APF is comprised of a voltage source inverter (VSI) based on pulse-width modulation (PWM) technique. Hence, undesirable power loss takes place inside VSI due to the presence of inductors and frequent switching of IGBTs. This is effectively minimized with inverter DC-link voltage regulation using a PI controller, whose gains are optimized using particle swarm optimization (PSO).