Design and Implementation of a High Power Battery Charger of a Hydroelectric-connected PV Plant

In remote areas, the scheme of networking grid complementarily by the large capacity of PV plants and the hydropower units becomes an important choice. After analyzing the design of a hydroelectric-connected PV plants, this paper presents a detailed requirement of a large capacity battery charger. The Buck circuit topology is adopted as the topology of the battery charger satisfying the demand the high charging efficiency and reliability and a 3 phase phase-shifted interleaving topology is adopted to resolve the problem of high power application. Finally a double-loop control strategy was designed for implementing the batteries three-stage charging control and PV MPPT function. A 150kW battery charger is developed and used in PV plant of the Yushu, Qinghai province, China. The experimental data acquired form lab and PV plant shows that the proposed topology and control strategy is correct and feasible.