Patent ID: 6476571
Filing Date: 2002-11-05
Classification: B60K,B60L,B60W,H02P,Y02T,Y10S

Abstract:
A multiple power source system that supplies an electric power to a three-phase motor, said three-phase motor having Y-connected windings,said multiple power source system comprising: a first direct current power source; a power control circuit that is disposed between said first direct current power source and the Y-connected windings of said three-phase motor and has switching elements, which are switched on and off to supply an electric power output from said first direct current power source to said three-phase motor; a second direct current power source that is different from said first direct current power source; and a unit that prevents said first direct current power source from being charged with the electric power output from said second direct current power source while said switching elements are switched off, wherein one terminal of said second direct current power source is connected with a terminal of said first direct current power source having an identical polarity, and the other terminal of said second direct current power source is connected with a neutral point of the Y-connected windings in said three-phase motor, said multiple power source system further comprising: a charging control unit that controls the switching on and off of said switching elements and uses the windings of said three-phase motor to boost a voltage of said second direct current power source, and charges said first direct current power source with the boosted electric power output, when lack of the power supplied from said first direct current power source is detected, before said first direct current power source drives said three-phase motor.