Enhanced Current Pulsation Smoothing Parallel Active Filter for single stage grid-connected AC-PV modules

On single stage PV converters the output power has a large amount of power pulsation at twice line frequency, causing PV module voltage and current fluctuation. However, a PV module should operate at a sufficiently small area around the maximum power point, in order to maximize PV generation. To overcome this defect a buffering storage unit between the PV module and the inverter, which performs the well known power decoupling, is inevitable. This paper presents an enhanced configuration of a current pulsation smoothing parallel active filter (CPS-PAF) which permits the elimination of the low frequency PV current ripple with significant smaller capacitor comparatively to the classical configuration. The enhanced CPS-PAF conception, control and effectiveness are validated by PSpice simulation results as well as by experimental results accomplished on a laboratory prototype.