Techniques in the Design and Stability Analysis of Fuzzy Proportional-Integral-Derivative Control Systems and Their Industrial Applications

This chapter reviews various types of conventional and fuzzy proportional-integral-derivative (PID) controllers, and their new developments in achieving autotuning—adaptive and robust capabilities. The chapter emphasizes two types of PID controllers: fuzzy PID controllers and conventional PID controllers. Both these controllers are not exactly comparable—in fact, it is generally impossible to have exactly the same conditions for a fair comparison of these controllers. As long as the fuzzy PID controllers work for some control problems for some systems that the conventional ones can't work out or don't work out so well, they have their own merits. Comparisons are actually difficult: fuzzy PID controllers have been developed for only five years or so and hence are certainly not as mature as the conventional ones that have a more than fifty-year history. There are still many drawbacks, weak-points, and technical problems inherent with various fuzzy PID-type of controllers, which is the very challenge that calls for further effort and endeavor from the research and engineering communities.