A modular PV charger with maximum power point tracking and pulse-charging schemes

This paper presents a modular self-controlled photovoltaic (PV) charger with maximum power point (MPP) tracking and pulse-charging schemes. The studied PV modules can be flexibly parallel-connected through interleaved operation using an Inter-Integrated Circuit (I2C) interface. The MPP tracking (MPPT) control of a PV panel is implemented by using a current-sensing technique with the on-state resistance, Rds(on), of the power switch. An expensive hall-effect sensor and additional current-sensing resistor are both not needed. A pulse-charging scheme is also designed to prolong the lifetime of the acid-lead battery. The operation principles and design considerations of the proposed PV charger are analyzed and discussed. A laboratory prototype is implemented and tested to verify its feasibility.