PCC Voltage Compensation of PV Inverter with Active Power Decoupling Circuit

Abstract

This paper proposes an algorithm for the point of common coupling (PCC) voltage compensation in single-phase photovoltaic (PV) inverter system. In single-phase power conversion system, the DC link capacitor voltage has a power ripple which is twice of the grid utility frequency. This ripple interferes with the maximum power operation point (MPOP) when tracking the maximum power point (MPP). Also, the power ripple affects on the lifetime of the DC link which consists the electrolytic capacitors. In order to eliminate power ripple, the active power decoupling (APD) circuit has been inserted. And film capacitor has been used instead of electrolytic capacitor to expand the lifetime of PV inverter. In addition, a method for compensating the PCC voltage fluctuation in the PV inverter is introduced. Both the simulations and the experiments for a single-phase PV inverter shows that the proposed method is able to compensate the voltage fluctuation