The active power and reactive power control for three-phase grid-connected photovoltaic inverters

This paper presents the active power and reactive power control for three-phase grid-connected photovoltaic (PV) inverters. With the proposed control strategy used PI method. The current command on the rotating reference frame is regulated by the feedback and decoupling current compensate. In order to guarantee the all maximum point power command is transferred to the grid, the d-axis current or active power command is calculated from power calculation algorithm. Moreover, the design guidelines of phase-locked loop (PLL) and current controller are also presented. Finally the concept of the proposed grid-connected inverter was verified by experimental results.