Sliding mode control of single phase grid connected PV system using sign function

This paper deals with control of a photovoltaic (PV) power generating single-phase system. The PV system consists of a DC-DC positive output super lift Luo (POSLL), a DC-AC converter, R-L filter and utility grid. The POSLL converter is used between PV panel and the DC-AC converter. A sliding mode control approach (SMC) using sign function is used for control of PV voltage and POSLL inductor current. The injected current to grid is also controlled by SMC method. To achieve maximum power point (MPP) of the PV panel, a maximum power point tracker (MPPT) known as perturb and observe (P&O) is employed. The MPPT provides reference of the PV voltage. For confirming the validity and the effectiveness of the proposed control approaches, a simulation by PSIM software under different operating conditions including various temperatures and radiations is presented and discussed.