Battery charging apparatus

A battery charging apparatus, comprising:

• a plurality of input terminals configured to be respectively connected to output terminals of respective phases of a three-phase AC dynamo;
• a rectifying circuit comprising a plurality of rectifying elements and a plurality of switching elements;
• a switching element control unit configured to control turning on/off respective switching elements of the rectifying circuit;
• and
• a pulse generation unit configured to generate a pulse signal by detecting passage of a reluctor disposed on a rotor of the three-phase AC dynamo,
• wherein the switching element control unit is configured to control the plurality of switching elements to set output voltages to a battery in a full-wave rectification state or an all-phase short-circuited state, and
• wherein the switching element control unit comprises:
• a potential difference detection unit configured to simultaneously detect potential differences between potentials of at least two input terminals of the plurality of input terminals and a ground potential of the battery, and configured to generate signals indicating the detected potential differences;
• and
• a specifying unit configured to determine a combination pattern of phases of the three-phase AC outputs input to the input terminals and the signals generated by the potential difference detection unit, and specifying a phase of the three-phase AC outputs input to the plurality of input terminals calculated from a relationship among the combination pattern, a generation timing of the pulse signal, and rise timings of the signals.