Fuzzy Robust Speed Controller for AC Drive Systems

Abstract

This paper investigates a speed control method for an induction motor drive system in which a Flux vector control is applied to the system. A Zeroing technique with an equivalent disturbance observer Predictive Controller are used to achieve the fast and robust controller of the system. Then this linear controller structure is changed by fuzzy logic such that the controller makes the system respond quickly if the error e is large and vice versa in order to obtain a robust controller which is insensitive to both the plant noise and the observation noise. Next, a variable structure PI controller by fuzzy logic for drive systems is introduced. Since the development of flux vector control is used in induction motor drives, ac servomotor control has attracted much attention, mainly due to its simplicity, ruggedness and low cost since induction motor is used. The robust and fast speed-control for an induction motor have been described, which the zeroing control method and combine with feed forward controller is used. In the case of noise sensitive systems sometimes high gain controllers have caused problems. In some cases, when the motor drive system is running, the operator must adjust the controller gain to suit the environment or certain conditions. So, if the controller gain can be changed when the operator operates the system, then the system will be perfect. As a result, the controller can be non-linear and the changing of the parameter values using fuzzy is realized.