A novel prediction control method for active power filter based on grey theory

This paper concerns with an investigation of a novel methodology applying Grey theory to the control of active power filter (APF). A GM(l,l) prediction model based on Grey theory is developed for harmonic current prediction, and a two-step ahead prediction control strategy is proposed to eliminate the control time delay. To validate the effectiveness of the method proposed, a three-phase power supply system with a nonlinear load is simulated using EMTDC. Simulation results show that the GM(l,l) model based prediction controller behaves very well for the varying load. For comparison the performance of a conventional deadbeat control method with one step ahead prediction is also simulated. It is also found from the simulation that the method proposed in this paper is more effective and can be easily realized without control time delay.