Motor control apparatus and control method

摘要

The technique of the present invention sets a torque voltage to be applied to a motor in response to a required torque and adjusts the duty of an inverter to ensure application of the torque voltage according to the observed voltage of a battery. In a motor controller constructed to attain such control, before a start-up of normal operation of the motor, a fixed duty is set for switching the inverter to apply a voltage to the motor. The value of electric current running in response to the applied voltage is measured. The mapping of the value of electric current to the source voltage in the case of switching the inverter at a fixed duty is stored in advance in the form of a table. The procedure reads the true value of the source voltage from the table and thereby specifies an offset error occurring in a voltage sensor of the battery. The procedure then corrects the observed voltage of the battery and adequately regulates the torque voltage.