Application of hybrid modeling and control technique to a non linear hybrid system

This paper presents a newer modeling and control implementation technique using multi state model approach for Two Tank Hybrid System (TTHS) which is a benchmark for nonlinear hybrid system. This class of hybrid system is a collection of subsystems defined on different sub-space, which are related by a switching logic. The MATLAB Simulink and Stateflow tools are used to formulate the multi state models and switching logic for TTHS. Three cases namely TTHS with single PID controller which is designed based on single linearized model, TTHS with as many PID controllers which are designed based on multiple linearized models and TTHS with as many PID controllers which are designed based on multi state model framework are considered. The real coded Genetic Algorithm is used to obtain the optimal PID control settings in all the three cases. The performances of the proposed PID control scheme based on multi state model framework using simulation on a TTHS are presented. The advantages of TTHS with PID control scheme based on multi state model approach over the other two cases are highlighted.