“…From the Kirchhoff's laws, we have: (4) , for and (5) and (6) We control and maintain the PV array operating point using the PV charger. The power loss of the PV charger, , is calculated from its input voltage, input current, output voltage, and output current, i.e., , , , and , respectively [11]. Due to the energy conservation law, we have: (7) where and are the battery's terminal voltage and charging current from the PV system, respectively.…”