Study Of Multiple Model Fuzzy-PID Control Algorithm For Temperature-stress Testing Machine

Temperature control system of Concrete temperature-stress testing machine (referred to as "the testing machine") has uncertainty and nonlinear, if corresponding controller designed by accurate mathematical model the corresponding controller, when the uncertain parameters dramatic changes, it is difficult to obtain satisfy result. Although many advanced control algorithms have been a preliminary application, and have solved some control problems, but frequent changes in a wide range of parameters would cause characteristics' change of control targets, the corresponding control problem has not been solved. Multi-model method of control theory and its application of concrete temperature - stress testing machine's temperature control system have studied in this dissertation. Based on the requirements of the testing machine, this dissertation proposes the multi-model fuzzy PID algorithm to solve non-linear, and change working conditions, strong disturbance, parameter uncertainty, and so on. This dissertation reads as follows:Introduce development of temperature control of concrete temperature-stress testing machine and the development of intelligent control's application in temperature control field.Based on studying of basic principle and research methods of multiple model adaptive control, the controller sets and switching algorithms, multi-model adaptive control indirect and direct multi-model adaptive control were studied.The multiple model fuzzy PID control algorithm is proposed. According to the concrete temperature-stress testing machine temperature control system characteristics, multiple sub-model and the corresponding fuzzy-PID controller have been create in some typical conditions. Through switch model with switch parameters based on output deviation and prevent frequent switch with amendment method, multi-model controller achieves the smooth switch.Create a simulation model of temperature control system of temperature-stress testing machine. Simulating results show that multiple model fuzzy PID control is simple and easy to implement in this dissertation. In a wide range of, this algorithm has better quality control and wider application.