DC side ripple voltage analysis and fuzzy PI control strategy research for APF

Owing to the problems of DC side capacitor value choice in the application of Active Power Filter (APF), this article presents a technique based on the analysis of the ripple voltage in DC side by graining appropriately the undulation control rate within the range of settings and control DC voltage so that the voltage fluctuation rate can reach minimum value under the condition of specific capacitance which is aimed at getting good compensation effects.