Single-phase grid-connected photovoltaic systems with power quality conditioner functionality

Future ancillary services provided by photovoltaic systems could facilitate their penetration in power systems. In fact PV converters can be designed to improve grid power quality implementing power conditioning functionalities. This paper presents a single-phase photovoltaic system with power quality conditioner capability. It provides grid voltage support at fundamental frequency and compensation of current and voltage distortion at the point of common coupling (PCC). Two topologies have been considered: in the first one the voltage and the harmonic compensation are provided by two different converters, in the second one only one converter is used. Both the proposed topologies are controlled with a repetitive controller that is able to compensate the selected harmonics. Simulation results allows comparing the presented solutions.