Adynamic Multi-attribute Decision Making Approach To Process Control Performance Evaluation

The control performance evaluation has received more attentions in the process control community,leading to various qualified methods.However,few studies have focused on slow-varying control systems.Practically,many production processes are of slow time-varying characteristics due to facility aging.Therefore,it is of practical significance to develop control performance evaluation methods for slow-aging time-varying processes.The thesis involves dynamic multi-attribute decision-making metrics into control performance evaluation methods.The main contents and achievements are listed as follows:1.A variable weighted decision-making method based on OWA is proposed.In the process of decision-making,an analytic hierarchy process(AHP)is used to construct a judgment matrix,and the weights of the attribute values in each interval are determined.Subsequently,based on the OWA operator,the decision matrix is aggregated,and the decision information in the aggregation process is firstly homogenized before heterogeneously combined by changing the weight values,achieving the decision result ultimately.2.An index combining system failure rate and running time is used to judge the system operation status of the selected interval.The overshoot,nonlinearity,output variance,and valve stickiness indices are selected as performance indicators.The variable weight multi-attribute decision-making method is employed to calculates the decision matrix based on historical data,obtaining the control system performance evaluation results.3.The proposed method is applied to a DMF recovery plant.Compared with the static evaluation method,the validity of this method for evaluating the control performance of slow-aging time-varying system is verified.