Research On Performance Assessment Method And Monitoring Technology Of Typical Process Control Loop

The performance assessment is important for the improving of control system in power plant. A new assessment method for comprehensive performance of typical control system was presented for the case of set-point change and stochastic disturbance existing simultaneously. In this method, the error data of control system were divided as the deterministic component and the stochastic component, and then the two components were used to calculate the tracking index and the stochastic index separately. Implementation steps of this method were also indicated. A numerical simulation and an actual data analysis for main pressure control system of a 1000 MW power unit were tested. The results show the effectiveness of this method.Real-time control performance monitoring(RCPM) is important in the real control system. The technology and layout of the RCPM are researched. Firstly, a real-time algorithm of trends extraction is presented; Secondly, a real-time algorithm of state identification based on the slopes of the adjacent sections is given; Then,a real-time delay estimation algorithm based on recursive least squares is proposed, in which the delay probability density function and forgetting factor are used; Lastly, the calculation of online performance assessment and the parameters whcich are monitored, are discussed. Real-time performance monitoring software is developed based on the foregoing theory and the GUI toolbox of Matlab. The effectiveness of the RCPM technology is proved by simulation.