RTDA Control And Application Research For General Multivariable Systems

Model Predictive Control(MPC)has shown its value and remarkable economic benefits in the fields of aviation,petrochemical and other fields.Although rich theoretical research results have been achieved in predictive control over the past decade,the gap between theory and reality has not been narrowed.The development of a practical and low-cost controller for the chemical industry process has become an urgent task.Ogunnaike et al.proposed that the next-generation controller RTD-A(Robustness,Tracking,Disturbance rejection-overall Aggressiveness)controller has the characteristics of simple model,direct relationship between parameters and system performance,making it unique in parameter setting and robustness.As an advanced step linear model predictive control(asLMPC),this paper expands its theory and application work as follows:(1)The research status and development of multivariable system,non-square system and RTD-A controller were systematically reviewed.The algorithm and block diagram expression of the single variable RTD-A controller were described in detail.Compared with MPC's representative Internal Model Control-PID(IMC-PID)and Dynamic Matrix Control(DMC),several aspects of control performance were compared.(2)The RTD-A controller is extended to general multivariable systems including square systems,fat systems,and thin systems.The prediction output is time-divided,and the objective function is reconstructed using weight coefficients.A concise interpretation for the general existence of the control law was provided together with a suggestion for judging this existence in practical applications.(3)Combining the Shell heavy oil fractionation column for the comparison of square and non-square systems with two multivariable decoupling controls,respectively.Demonstrated the flexibility,friendliness,and excellent robustness,anti-noise performance and dynamic control capability of the RTD-A controller.(4)By constructing the third-order tank pilot control model,the simulation structure of the general chemical dynamic process was given and the three time conceptswere clarified.A variety of differential equations were compared to solve the algorithm,and a quantitative comparison of the performance parameters was proposed,and preliminary conclusions were obtained.