Multi-input integrated buck-boost converter for photovoltaic applications

In this paper analysis and control of two-input integrated DC-DC converter, suitable for photovoltaic (PV) applications, is presented. This converter is essentially combination of individual buck and buck-boost converters feeding a common DC bus. However, on account of the integration there is only one inductor is sufficient enough for power conversion in both the converters. Here, the buck-boost converter, with maximum power tracking, extracts complete power from the PV source and feeds into the load, while the remaining load power demand is drawn from the stand-alone DC source, which is equipped with single-loop voltage-mode controller for DC bus voltage regulation. Closed-loop converter performance of this converter is simulated and compared with the theoretical predictions. Simulation studies are presented here for constant resistive and battery type of loads. The load power distribution among the sources is demonstrated.