PID Parameter Self-tuning Design And Implementation

PID controllers,because of its simple algorithm, good robustness and high reliabili-ty characteristics, are widely used in industrial process control. However, parameters ofPID controller are not easy to determine,then the concept of self-tuning was came upwith.Since the concept of self-tuning appeared, self-tuning became a hotspot in the fileof control.After years of development,theorys relate to self-tuning are proposedconstantly,but each one has own shortcomings.In order to solve this problem,this paperdesigns a new kind of self-tuning controller bases on gradient algorithm which from thetheory of optimum.In order to be able to research on self-tuning method more completely,classical anddigital PID control theory,principle and algorithm of self-tuning,optimization theory isstudied.After this,grandient algorithm which usually used in system identification isapplied to the process of determining optimization parameters.Finally,hardware isdesigned bases on the requirment of self-tuning,which includes storage module,LCDmodule,USB input module and network interface.The design in this paper overcome theshortages of which the self-tuning methods exited have.For example,self-tuning methodbases on model relies heavily on the identification accuracy and self-tuning methodbases on rules is hard to forge the rules.At lase, the design achieved the function ofself-tuning.