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Abstract

Battery and load management on a stand-alone electric generator from renewable energy sources manages the process of battery charging and discharging. This study discusses design, simulation and implementation of Synchronous Non-Inverting Buck-Boost (SNIBB) using four-switch H-bridge to control current and voltage of multi-stage charging lead acid battery. When the voltage is under 2.4 V/cell, the charging current of battery is kept constant using constant-current (CC) mode, then the voltage is kept constant on constant-voltage (CV) mode until the charging current reaches 5% and it is switched to float-charge mode with set point voltage 2.25 V/cell. Controlling battery charging/discharging and load is using two switches with the parameters, such as power electric source, battery capacity, and load. The implementation of the design is using microcontroller ATMega 16 with PI controller. As on CV and CC mode, SNIBB circuit is able to keep voltage and current appropriate to the set point with the changes of input voltage. On CC mode, when the set point of current is increased, the charging time is faster. The result shows that the battery management designed is able to control charging and discharging the battery to the load.