شبیه سازی کنترل جریان موتور القائی به کمک روش هیسترزیس

ABSTRACT

The aim of the Paper is to design a hysteresis band PWM (HBPWM) current controller for a three level voltage source inverter (VSI) through a fuzzy approach. The fuzzy approach has been selected for the Paper since it has the potential to provide an improved method of deriving non-linear models which is complementary to conventional techniques. A Sugeno type fuzzy inference system is used in the proposed fuzzy controller. To illustrate the validity of this approach, an indirect vector controlled induction motor (IVCIM) drive has been considered as its application. The vector control scheme essentially attempts to decouple the torque and flux controls of an induction motor. In order to carry out this decoupling of torque and flux, the space vector model is implemented and a HBPWM current controlled inverter is used in order to supply variable voltage, variable frequency to the motor. Fuzzy set theory has been applied to the HBPWM controller. The proposed fuzzy controller in which the change of current and rate of change of current have been used as inputs. A set of decision rules expressed in linguistic variables are established to relate input signals to the output (control) signal. A comparison between conventional controller and the proposed fuzzy controller reveals that the effectiveness of fuzzy controller.