M. Matsuno et al., DETECTION OF SHAFT-EDGE FIELD OF INDUCTION-MOTOR FOR STABLE TORQUE CONTROL, IEEE transactions on magnetics, 32(5), 1996, pp. 5004-5006
New detection of the rotor information of squirrel-cage induction moto
rs for a stable torque control is carried out by using a highly sensit
ive Magneto-Impedance micro magnetic sensor. A magnetic field detected
near an edge of the rotor shaft is estimated to be proportional to th
e rotor current with a slip frequency (psf/2) and a torque when the mo
tor is driven with a constant V/f inverter, A stable control for the s
tationary torque is realized independently of the motor temperature va
riation.