EQUIPMENT AND METHOD OF COMPENSATING VARIABLE LOAD INDUCTANCE FOR MOTOR DRIVER CIRCUIT

PROBLEM TO BE SOLVED: To prevent the decrease of the maximum speed of a motor for fixed motor torque, and to improve the performance of the motor whether a core is saturated or unsaturated by changing over an inductance compensating value. SOLUTION: The variable load inductance compensator for the motor driver circuit has an amplifier with an inductance compensating circuit 4 corresponding to a variable inductance motor such as a reluctance changeover type motor. The inductance compensating circuit 4 has a changeover means alternately connecting two or more of inductance compensating values and at least one inductance compensating value of a plurality of the above-mentioned inductance compensating values to the inductance compensating circuit 4 providing at least first and second inductance compensation for driving the motor 3 in response to the change of the inductance of the motor 3 or releasing connection.