Grid-Connected Shunt Active Photovoltaic Filter

Abstract

In this work, that partially validates an obtained patent [18], a structure of grid-connected three-phase three-wire shunt active filter with photovoltaic generator (SAF/PVG), without DC/DC converter, is proposed to compensate the electrical grids from perturbations (like harmonics, reactive power, unbalance, etc.), while injecting to the loads/grid the maximum power (MPPT) of the PVG. In this structure, which without Dc/Dc converter is more reliable and economical, an extended instantaneous real and imaginary powers method, with an advanced PLL, is proposed to identify, jointly or individually, all current perturbations, as well as current at maximum PV power to be injected in phase with PCC’ fundamental voltage. The DC voltage control loop is, in this case, maximum power-based, unlike the conventional maximum current-based loop, which allows easier integration MPPT of the PVG into the instantaneous powers method. In this research, the DC side voltage, of the SAF/PVG, is equal to the voltage at maximum PV power, provided by P& O algorithm. Besides, only one current control loop is necessary in the proposed control strategy. Finally, the proposed structure including the control strategy are validated via simulations on a conventional nonlinear industrial load.