It is the probability of the mutation process in GA. The mutation inserts new genetic material in the population. Low mutation rate prevents that a value remains as the best solution for generations. High mutation rate becomes excessively random the research of solutions in the algorithm, resulting in loss of optimal solutions.
Published in Chapter:
Robust Fuzzy Digital PID Controller Design: A Contribution for Advanced Studies in Control and Automation
Danúbia Soares Pires (Federal Institute of Education, Science, and Technology, Brazil) and Ginalber Luiz de Oliveira Serra (Federal Institute of Education, Science, and Technology, Brazil)
Copyright: © 2015
|Pages: 34
DOI: 10.4018/978-1-4666-7258-1.ch008
Abstract
A robust fuzzy digital PID control methodology based on gain and phase margins specifications is proposed. A mathematical formulation based on gain and phase margins specifications, the Takagi-Sugeno fuzzy model of the process to be controlled, the structure of the digital PID controller, and the time delay uncertain system are developed. A multiobjective genetic strategy is defined to tune the fuzzy digital PID controller parameters, so the gain and phase margins specified to the fuzzy control system are found. An analysis of necessary and sufficient conditions for fuzzy digital PID controller design with robust stability, with the proposal of the two theorems, is presented. Experimental results show the efficiency of the proposed methodology in this chapter, applying a platform control in real time of a thermic process through tracking the reference and the gain and phase margins keeping closed the specified ones.