A FUZZY ADAPTED FIELD-ORIENTED MECHANISM FOR INDUCTION-MOTOR DRIVE

The detuning of an indirect field-oriented induction motor drive due t o variation of rotor resistance may lead to low efficiency and poor tr ansient response. To improve this, an induction motor drive with fuzzy adapted field-oriented mechanism is proposed. During steady state con dition, an adapted slip angular speed signal is synthesized by a fuzzy controller and used to adjust the original estimate of slip angular s peed signal such that minimum stator current is obtained. When the tra nsient due to command or load torque change occurs, the fuzzy tuning m echanism is temporarily inhibited and the final value of the adapted s ignal is held. A discrete two-degree-of-freedom controller (2DOF) is d esigned to yield good speed command tracking and load regulating respo nses. The effectiveness of the proposed motor drive is demonstrated ex perimentally.