Fuzzy self-tuning pi control of pm synchronous motor drives

In this paper, a new gain self-tuning method for PI controllers based on a fuzzy inference mechanism has been proposed and implemented. The essential idea is: (1) define a dynamically changed reference trajectory in the error and error derivative plane, called a 'sliding trajectory'; (2) compute the error area between the sliding trajectory and the e ective one with a special algorithm, and use this quantity as a performance index to evaluate the system response; (3) draw a fuzzy relationship between a PI gain correction parameter and the performance index; (4) based on the fuzzy inference mechanism, PI gains are calculated and tuned. The proposed method has been verified through simulations, using the speed control of a PM synchronous motor drive system as a testbed. The results obtained demonstrate the effectiveness of this novel method.