Design and Control of Single-Phase Solar PV Inverter with MPPT Algorithm

In this paper, a high performance, duel stage and low cost solar powered solar PV inverter is proposed for the stand-alone operation. First, the dc-dc boost converter is designed based on the step-up voltage ratio as demanded by the inverter. The maximum power from the PV system can be extracted by using a commonly used P & O maximum power point tracking algorithms. The output dc power produced by the dc-dc converter is supplied to a single-phase, full-bridge dc- ac converter (inverter). A dual loop control scheme is used to enhance the power quality of the inverter. The outer voltage loop is used to maintain a constant load voltage at any load conditions whereas the inner current loop is used to enhance the transient response against the sudden load fluctuation conditions. Both loops comprises of the conventional PI controller. The steady-state response in terms of low THD and dynamic response in terms settling time is measured to evaluate the efficacy of the proposed dual-loop control structure. Finally, the proposed controller is imposed to a 2 KVA, 110 V (rms), 50 Hz dual-stage solar inverter. The simulation results ensure the tremendous MPPT performance of efficiency 99.17 % whereas low THD of less than 3 % appeared across the PV inverter output voltage.