Parameter detection of a DC brushless motor and vector control of that motor

A constant detecting apparatus 15 comprising a detecting unit 26 and a calculating unit 27. The detecting unit 26 is structured comprising a rotation sensor 41, a torque sensor 42, a position sensor 43, a rotor temperature sensor 44, a winding temperature sensor 45, a phase voltage detector 46, and phase current detectors 47 and 47. The calculating unit 27 calculates the induced voltage constant Ke that changes depending on the motor temperature Tmag while the motor 11 is being driven based on each of the detected signals from the detecting unit 26, and at the same time, the d axis current Id and the q axis current Iq are calculated after elimination of the iron loss, and the d axis inductance Ld and the q axis inductance Lq in the actual operating state of the motor 11 are calculated.