Patent ID: 7339346

Claim:
A motor drive control device that controls a motor having three or more phases, comprising: a d-q voltage calculating unit that calculates a voltage ed which is a d-axis component of a counter-electromotive force, and a voltage eq which is a q-axis component of the counter-electromotive force; a q-axis command current calculating unit that calculates a current command value Iqref, which is a q-axis component of a current command value, on the basis of the voltage ed and the voltage eq; a d-axis command current calculating unit that calculates a current command value Idref that is a d-axis component of the current command value; a phase current command value calculating unit that calculates phase current command values of the respective phases on the basis of the current command values Iqref and Idref; a motor current detecting circuit that detects motor phase currents of the respective phases of the motor; and a current control unit that controls phase currents of the respective phases of the motor on the basis of the phase current command values and the detected motor phase currents; wherein differences between the phase current command values and the detected motor phase currents are inputted to the current control unit.