Current ripple cancellation of multiple paralleled boost converters for PV/battery charging system with MPPT

For conventional paralleled PV sources, the current ripple at the load side increases when the ripples are added up from each converter, which also reduces the life time of the battery storage. Even though the ripple is able to be reduced by increasing switching frequency, the extra switching losses must be taken into account. In this paper, a switching technique is proposed based on paralleled multiple-input sources with boost converters. Since the current ripple of the battery charging current can be minimized without the restrictions of source voltages, currents and duty cycles, the Maximum Power Point Tracking (MPPT) algorithm is also able to be implemented with the proposed technique for integrating renewables into the smart grid. The proposed technique is validated through detailed numerical analysis, simulation and experiment results.