Full Fuzzy Logic Controller Based Vector Controlled Induction Machine Drive

Vector control technology is one of the famous torque control technologies of the induction machine drives. With vector control of induction machines, the torque-pro- ducing and flux-producing current components are decoupled and the transient response characteristics are similar to those of a separately excited DC machine, and the system will adapt to any load disturbances and/or reference value variations as fast as DC machine. Nowadays, vector control techniques incorporating fast microprocessors and DSPs have made possible the application of induction machine drives for high performance application where traditionally only DC drives were applied. However, the performance of vector controlled induction machine drives relies on the accuracy of the motor parameters heavily. So the accurate motor parameters and a robust speed controller are the most important parts for a vector controlled induction machine drives. Artificial intelligence is an alternative solution because of its robustness in solving the uncertain and nonlinear problems. A vector controlled induction machine drive, which is fully based on fuzzy logic controllers, is introduced in this paper. There are three fuzzy logic controllers will be used in such a drive system. One of the controllers is the speed controller. The other two are current controllers, which is used to decouple the torque-producing and flux-producing current components under the rotor flux oriented reference frame. Moreover, the relationship between the scaling factors of fuzzy logic controller and the system performance is investigated in this paper through simulation and experimental studies.Parameter estimation technology is one of the most important factors for a high performance induction machine drive. Based on the self-commissioning method introduced by Russel J. Kerkman[1], a simple current synchronization method and a compensation method of the phase shift of the measured motor voltage, which is introduced by the lowpass filter, are presented in this paper.Many simulation and experimental studies are performed to verify the feasibility of the proposed vector controlled drive and the parameter estimation method.