Patent ID: 8610414

Claim:
A vehicle-mounted multi-phase converter comprising: a plurality of booster coils; and a switching circuit for generating an induced electromotive force at each booster coil by switching of current flowing to each booster coil; for applying an output voltage, based on an input voltage and the induced electromotive force generated at each booster coil, to a vehicle drive circuit; wherein said switching circuit switches current flowing to each booster coil so that the booster ratio of said output voltage with respect to said input voltage varies in a predetermined variable range in accordance with travel control of the vehicle; and a coupling factor indicating the extent by which the induced electromotive force at one of said plurality of booster coils contributes to the voltage between terminals of another booster coil has a value which is determined such that, when said booster ratio is a value less than or equal to the middle of said variable range, the current ripple component of each booster coil is smaller than the current ripple component of each booster coil in the case where said coupling factor is 0.