Design Of Fuzzy Controller For Non-Minimum Phase Systems Based On Genetic Algorithms

In the control engineering, the non-minimum phase system is very common and more restive, and two kinds of intellectual control method have been designed in this paper. Firstly, aiming at the characteristic of non-minimum phase system, we have designed fuzzy controller to control the system and optimized fuzzy rules and parameters with improved Genetic Algorithms. Owing to the negative shoot which may occurred in non-minimum phase system, we have introduced new object functions into it, and we have amended fuzzy rules which were not optimized by hand and have got ideal control result. Secondly, for the steady-state error which may caused by fuzzy controller, we have put forward a kind of Fuzzy-PID compound controller which switches based on fuzzy rule. It realizes stable transition from one control mode to another. We have introduced the parallel idea into Genetic Algorithms, and have optimized parameters of the compound controller. The results of simulations show that the fuzzy controller optimized by this method has good controlling quality, strong robustness and anti-interference.