A Second Order Generalized Integrator Based Flexible Power Control for Single-Phase Photovoltaic Grid-Connected Inverter

Abstract

According to the feature of single-phase photovoltaic(PV) grid-connected inverter, a flexible power control method for single-phase PV grid-connected inverter in stationary coordinate system is proposed. Two orthogonal voltages, one of which is of the same phase as grid voltage and the phase of another one lags behind the grid voltage by 90°, are obtained by second order generalized integral(SOGI) algorithm, and the fast tracking of given current can be implemented by proportional quasi-resonant(PQR) controller in the two-phase stationary coordinate system. Experimental results show that using the proposed control method the decoupling control of active and reactive power can be realized, and the control system possesses good static and dynamic performances.