Researches On The Parameter Adjusting Strategy Of Internal Model PID Controller Based On Performance Assessment

A good parameters adjustment’s method of PID controller can not only reduce operating burden, but also make the system at the best operation state, so how to adjust the parameters of the PID controller is always the main subject of the PID controller’s design. However adjusting parameters has a bad effect on the system if late or early, choosing the right time to adapt is very important. This paper evaluates the performance of the system by evaluation index, then as the basis when we adjust the parameters of the system. This paper mainly does the following aspects:(1) Introduced the related knowledge of performance evaluation and internal model PID controller’s design. Introduced the calculating method of performance evaluation index, and then given the minimum variance system’s performance evaluation index’s calculation, this paper introduces the theory of internal model control and the relations on internal model control and feedback control, so as to draw out the internal model PID controller and the design of internal model PID controller.(2) For the existing problems on application of internal model PID in industrial, the performance evaluation is introduced, this paper introduces the adjustment methods of the internal model PID controller based on performance evaluation, and giving the method on controller parameters’ adjusting when performance does not meet the requirements, the main steps of the method are simplified model, parameters identification of simplified model, controller parameter’s design, performance evaluation.(3) Analyzed the reason of surge on compressor, refined the compression anti-surge control model according to the actual system, identified the parameters of the model on compression anti-surge control through the closed loop identification methods, adjusted PI controller’s parameters of backflow preventer based on the internal model PID control thoughts, and at the same time introducing evaluation of performance, when the performance of system does not meet the requirements, adjusted the PI controller parameters of backflow preventer, so input quality flow is always greater than surge flow of compressor. The simulation analysis shows that identify of model is satisfactory form the precision, the system can adjust the controller’s parameters in the appropriate time, and the performance of the system has the obvious improvement after that.