A multi-function power quality utility for connecting co-generation systems to the power mains

This paper proposes a multi-functional power quality utility for linking co-generation systems to the power mains via an standard shunt active power filter together with a dc/dc converter that connects the co-generator to the dc-link. The main function of this utility is to regulate the active power delivered from the co-generation system. Besides this function, the utility can also compensate the harmonics generated by non-linear loads, supply reactive power to the mains, and regulate the voltage at the point of common coupling (PCC). These compensation schemes use a different control strategy, which do not require the load current measurement for harmonic detection. This reduces the number of current sensors employed and their cost of implementation. These power quality objectives can be obtained even though the power mains is unbalanced. The feasibility of the proposed control system is validated by experimental results.