US 2003/0146726 A1 · Load driver with power storage unit

Abstract

In a load driving arrangement, electric power is supplied from an auxiliary battery to a main power supply when the power stored by charging in the main power supply is scarce at the startup of the system. The power is supplied to the main power supply by closing relays to connect the auxiliary battery to the neutral point of an auxiliary motor, operating a switching transistor of a bottom arm of an auxiliary-related inverter based on a command from a control circuit, stepping up the voltage from the auxiliary battery by using a coil of the auxiliary motor as a reactor, and supplying the step-up voltage to the main power supply thereby charging the main power supply. At this time, a drive-related inverter and a DC/DC converter are stopped. When the main power supply is charged to a sufficient degree, the relays are opened to drive each load. Accordingly, the load driving arrangement achieves the function of charging the main power supply at low cost when the power stored therein is scarce at the system startup.

Claims11

Dependent claims

A load driver comprising:

an AC motor;
a first power supply outputting a first voltage which is a DC voltage;
a second power supply outputting a second voltage which is a DC voltage;
an inverter receiving said first voltage, converting said first voltage into an AC voltage, outputting said AC voltage to said AC motor, and driving said AC motor;
a converter stepping down said first voltage, outputting the step-down voltage to said second power supply and charging said second power supply;
and
a control circuit, wherein when said first voltage is lower than a predetermined voltage,
said second voltage is supplied to a coil of said AC motor, and
said control circuit controls said inverter to step up said second voltage by said coil of said AC motor and said inverter, output the step-up voltage to said first power supply and charge said first power supply, and stops said converter.

6 more elements

Dependencies are inferred from the claim text.

Load driver with power storage unit

Life of this patent

Load driver with power storage unit

Life of this patent

Abstract

Claims11