A study of grid-connected PV-AC module with active power decoupling and ESS

Because AC module system is directly connected to grid source, power pulsation is appeared at AC module input capacitor. So, it can adversely affect maximum power point tracking (MPPT) control. Furthermore, photovoltaic (PV) module power can be fluctuated with varying irradiation while constant load demand. To reduce power fluctuation for MPPT control and stabilize the PV system with varying conditions, conventional flyback converter has auxiliary circuits for active decoupling and energy storage system (ESS) is proposed for energy efficiency. Proposed AC module system can solve the above problem (i.e. power pulsation, varying irradiation and load demand) by auxiliary circuit operation. But when the proposed AC module system is operating, it has various modes according to power flowing. In this paper, analyzes proposed AC module of operating modes, which show perform the overall system operation. To confirming proposed AC module system, verified by PSIM simulation result.