Grid-connected photovoltaic system with power factor correction

A combined grid-connection/power-factor-correction technique for a photovoltaic (PV) system is proposed in this letter. A maximum power point tracking dc/dc converter served as a charger for the battery bank. A bidirectional inverter is applied as a generator/discharger during daytime, supplying power to the load. The inverter can also be used as a charger to maintain the minimum required voltage level of the batteries when the PV power is insufficient. Experiments on a 1-kW PV system show satisfactory results of the power management and the unity power factor at the utility side.