A New soft switching algorithm for active and reactive power control in three phase grid connected PV plant

A new approach allowing a soft switching between implemented controls in the grid connected PVG is proposed in this paper. In fact, in grid connected mode, generally the MPPT control is adopted allowing to inject maximum power to the grid with a unit power factor. Nevertheless, in powerful PV plant, the needs of grid vary in power demand as well as in reactive or active power. Therefore, a sliding mode control is adopted on the inverter side in order to satisfy the injected active and reactive power. The switching algorithm controls the reference of active power and decides which control loop operates ensuring a safe operation zone of the PV plant. The simulation results prove the efficiency of the proposed switching algorithm namely the absence of injected current peak and stability of the grid.