For the problems of bulky, low charging efficiency and low input power factor, etc. of traditional charger for mine-used lead-acid battery, a new type of smart charger was developed. The charger, composed of multi-link voltage power units can achieve continuous and adjustable transformation from input three-phase AC voltage with two standards to DC voltage of 0~300 V and current of 0~120 A through phase shift control of square wave pulse of IGBT inverter.
Experimental results show that the charger has achieved three-stage operating mode from constant current to constant voltage and then to the float charging. The voltage and current are relatively stable, the electrolyte density reaction of the battery group is stable without bubbles and the temperature doesn’t change obviously in the charging process.