Motor driving device and steering system
AssigneeDenso Corporation
InventorsHaruo SUZUKI, Takashi SUZUKI
Life of this patent
Estimating the term…
Abstract
A control unit determines a presence or absence of a short-circuit failure with respect to a target switch which is a phase-opening switch to be determined. At this time, after opening all the phase opening switches, the control unit drives an inverter to connect a power supply line provided with the target switch among the phase opening switches to ground. The control unit determines that the target switch has a short-circuit failure when a voltage of the power supply line in which the target switch is not provided is smaller than a predetermined voltage.
Claims10
A motor driving device comprising:
- an inverter connected to a motor of multiple phases via power supply lines to supply a voltage selectively to the multiple phases of the motor;
- phase opening switches provided in the power supply lines, respectively, for opening and closing a current flow path between the inverter and the motor;
- a pull-up resistor unit connected closer to the inverter than the phase-opening switches in the power supply lines to supply a predetermined voltage from a power supply to the power supply lines;
- a short-circuit determination unit configured to determine a presence or absence of a short-circuit failure of the phase opening switch, which is to be subjected to a short-circuit failure determination as a target switch;
- and
- a voltage detection unit configured to detect a voltage of the each power supply line, wherein
- the phase opening switch is configured to supply a current from the inverter to each phase of the motor in an open state thereof;
- the short-circuit determination unit is configured to drive all of the phase opening switches to open, then drive the inverter to connect the power supply line including the target switch among the phase opening switches to a ground, and determine that the target switch has the short-circuit failure in case that a target voltage detected by the voltage detection unit is lower than the predetermined voltage, the target voltage indicating a voltage of the power supply line which is other than the power supply line provided with the target switch.
A motor driving device for a motor of multiple phases which are supplied with a voltage from a power supply through an inverter and power supply lines connecting the inverter and provided in correspondence to the multiple phases, the motor driving device comprising:
- phase-opening switches provided in the power supply lines between the inverter and the motor, respectively;
- a resistor unit connecting the power supply lines to the power supply;
- a voltage detection unit connected to the power supply lines to detect a voltage of each of the power supply lines;
- and
- a control unit configured to determine a short-circuit failure of the phase-opening switches, wherein the control unit is configured to:
- open all of the phase-opening switches to interrupt electric connection of the motor to the inverter and the resistor unit;
- connect only one power supply line among the power supply lines to a ground;
- compare the voltage of another power supply line among the power supply lines with a predetermined value;
- and
- determine the short-circuit failure of one phase-opening switch provided in the one phase-opening switch when the voltage of the another power supply line is smaller than the predetermined value.
Dependencies are inferred from the claim text.