Flicker Mitigation by Optimization of Voltage Control

Available inverter-interfaced distributed generation in the distribution grid could be used for mitigation of voltage flicker. By providing reactive power within few cycles and compensating change in voltage they thereby improve the power quality. The theoretical performance of a generic PI control and a more detailed Q(V) control model for the mitigation of voltage flicker is investigated. For this analysis defined flicker levels are generated in the CIGRE European LV grid topology. A genetic algorithm is used to optimize the control parameters to obtain optimal flicker reduction for each defined voltage flicker level and its individual flicker frequencies as well as over its entire flicker frequency spectrum. Resulting flicker levels are compared to the results obtained from using standard parameters or with additional time delays. The comparison shows that ideally flicker reduction is possible to the extend of 77%. However, the more detailed model achieve mitigation only up to 17%.