| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric power steering device free of interruption of the assist of the hand steering force even if a current sensor of a motor control device is in failure and having a redundancy system so as to continue the assist of the hand steering force. SOLUTION: The electric power steering device is equipped with a motor 15, a power supply 11, a motor driving circuit 25 installed between the motor 15 and the power supply 11 and making the PWM control of the current to feed to the motor 15, and the current sensor 29 to sense the current flowing in the motor 15, wherein the voltage of the wiring to connect the motor driving circuit 25 with the power supply 11 is sensed, and the resistance of the wiring is judged on the basis of the duty ratio in the PWM control of the obtained voltage to the current value given by the current sensor 29, and when the current sensor 29 goes in failure, the current flowing in the motor 15 is presumed on the basis of the resistance. COPYRIGHT: (C)2004,JPO |
