Fuzzy self-tuning PI control of PM synchronous motor drives

In this paper, a new gain self-tuning method for PI controllers based on the fuzzy inference mechanism has been proposed and implemented. The essential idea is to: (1) define a dynamically changed reference trajectory in the error and error derivative plain, known as a “sliding trajectory”; (2) compute the error area between the sliding trajectory and the effective one with a special algorithm, using 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; and (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 obtained results demonstrate the effectiveness of this novel method