Cascaded DC-DC Converters as a Battery Charger and Maximum Power Point Tracker for PV Systems

This paper introduces a cascaded dc-dc converter which combines both Ćuk and buck converter topologies to extract maximum power from photovoltaic arrays while supplying a controlled constant current/voltage to the battery simultaneously. The converter uses two control signals; one for maximum power point tracking, another for battery charger control providing constant current/voltage to the battery. The advantage of this converter is extracting the maximum power of the PV array avoiding battery damage caused by variable MPPT voltage. Batteries need constant voltage and current for charging to avoid the damage and to extend its lifetime. Therefore, it is reliable to combine the battery charger control and the maximum power exploitation using two control signals simultaneously.