Electrically operated power steering device

An electrically operated power steering device for giving steering auxiliary force to a steering mechanism of a vehicle by driving an electric motor in accordance with steering torque applied to an operation unit for vehicle steering, the electrically operated power steering device comprising:

• a steering state detecting unit for detecting a steering state in the vehicle steering;
• an electric current detecting unit for detecting an electric current flowed to the electric motor and outputting a detecting value of the electric current;
• a motor driving unit for driving the electric motor in accordance with a first command value;
• a voltage raising unit for raising a voltage to be supplied to the motor driving unit in accordance with a second command value;
• a motor driving control unit for calculating a command value for feedback control of the electric motor as the first command value on the basis of a deviation between a target electric current value set on the basis of the steering torque to the electric motor and the detecting value of the electric current flowed to the electric motor, and giving the first command value to the motor driving unit;
• and
• a voltage raising control unit for calculating the second command value such that the voltage raising unit is not operated when the calculated first command value is a predetermined threshold value or less, and the voltage raising unit raises the voltage in accordance with the steering state when the calculated first command value exceeds the threshold value, and giving the second command value to the voltage raising unit.