Digital Implementation of a DC Bus Voltage Controller for Four-Wire Active Filters

This paper presents the digital implementation of a DC bus voltage controller for three-phase four-wire active filters. Active filters can only operate if a control system is used to regulate the DC side voltages of its power converter. Using a split DC link capacitor converter topology the control system purpose enables the total DC voltage regulation and voltage sharing across capacitors. System modelling and controllers syntheses are realized and presented in the paper. Experimental results are shown enabling to highlight the behaviour and robustness of the digital control system proposed