Piecewise Nonlinear Hybrid Systems Modeling And Control Research

Hybrid system is the complex system which contains continuous and discrete dynamic process both influencing and interacting with each other. The piecewise nonlinear system is a class of system with an approximation of the complicated and nonlinear system by a group of simple continuous dynamic linear system models. The piecewise nonlinear system is a kind of typical hybrid system, containing model switching events. This dissertation uses the mixed logical dynamical model theory to research the modeling and control problems of the piecewise nonlinear system, the main contents are as follows:(1)The general control problem of piecewise nonlinear system is studied. The design method of multiple-model-PID-controller is introduced. The simulation results show that for the piecewise nonlinear system, the general control method is hard to make excellent control performance. The new modeling and control theory is need to accurately describe hybrid characteristics of the piecewise nonlinear system.(2)The hybrid model of the piecewise nonlinear system is studied. Based on the of the mixed logical dynamical model form, the general structure of hybrid system is analysis. Then mixed logical dynamical modeling steps are summarized. The mixed logical dynamical modeling theory is applied to the nonlinear system. For several typical piecewise nonlinear systems, the different modeling process is introduced in detail, and the respective complete model expression is given.(3)The predictive control of hybrid system with mixed logical dynamical model is studied. The predictive control theory can be extended to hybrid system. This dissertation studies the predictive control of mixed logical dynamical model using quadratic performance index and linear performance index, and discusses the stability of the control system. The simulation results prove the effectiveness of the predictive control algorithm.(4)The application of predictive control for multiple water tanks hybrid system is studied. A low cost solution based on the OPC communication for realizing hybrid predictive control is put forward. On the hardware platform of JX-300X DCS system, OPC client program is developed by the Matlab software. The hybrid predictive control is in successfully applied in the multiple water tanks hybrid system.