Error-Error Principle And The Research Of Its Simulink In Power Plant Thermotechnical Process Control

PID controller has the character of simple construction and good robustness, and such it is wide used in thermal control process. During the past forty years, amount of design methods of PID controller has occurred, while the formal design methods are all based on the simplified first-order added up with pure delay. The adjusting equation based on the simplified first-order added up with pure delay can not definitely be used in the high-order object of thermal control process, so the result is not so satisfying. The Error-error principle is put foreword by Han Jinqing, a Chinese Academy of Sciences research fellow, and has made certain achievements. Using the Error-error principle in the power plant control system design is put foreword in the paper.Firstly, it is analyzed in the paper about the merits and shortcomings of the PID controller. Secondly, deeply research the Error-error principle. In fact, Error-error principle is to optimize each section of control system, processing input signal with nonlinear tracking-differentiator, properly adjusting the transition and receive differential signal, solving the contradict problem of fast speed and over control, differentiator physically can not be realized. With the extended state observer to estimate the state of controlled objects including the uncertain and not modeling objects and compensate. With the nonlinear combination to deal with the error between the setting transition and state estimate, forming the control signal after compensate the disturb estimate data. Combine the above three key parts in different ways and then can get Nonlinear PID Controller and Active Disturbances Rejection Controller. Finally, put the above two controllers into used in the fields of power plant thermal object control, in this paper, the main steam temperature NLPID control system, the main steam temperature ADRC control system, the reheat steam temperature ADRC control system, the boiler steam pressure ADRC control system and unit plant ADRC coordinated control system etc. The results indicate that with the nonlinear PID controller and ADRC, the power plant thermal object control system has good control character and robustness.