Patent ID: 7813626

Claim:
A motor controller comprising: motor control signal output means that outputs a motor control signal; a driver circuit that supplies a three phase drive power to a motor based on the motor control signal; and anomaly detecting means, wherein the motor control signal output means includes electric current command value calculating means and motor control signal generating means, wherein the electric current command value calculating means calculates a d-axis electric current command value and a q-axis electric current command value of a d/q coordinate system as electric current command values, wherein the motor control signal generating means converts each of detected phase electric current values of the motor into a d-axis electric current value and a q-axis electric current value of the d-q coordinate system, and generates the motor control signal by performing feedback control in such a manner that the d-axis electric current value and the q-axis electric current value follow the d-axis electric current command value and the q-axis electric current command value that have been calculated, wherein the motor control signal output means performs a field weakening control in which the d-axis electric current command value is set to a negative value in correspondence with an rotation angular velocity of the motor, wherein the anomaly detecting means detects an anomaly if flow of electric current fails in any of phases of the motor, and wherein, if the anomaly is detected, the motor control signal output means outputs the motor control signal instructing to use phases free from the anomaly as electric current flowing phases, and prohibits the field weakening control.