Hybrid systems contain both continuous dynamics and discrete elements, where discrete transitions happen between different continuous operating modes as a consequence of certain events. The notion of modeling these types of systems is discussed in regard to the four tank process, which has hybrid and nonlinear characteristics. This paper describes the modeling of this system in Simscape software and a hybrid model is created as well, with a hybrid controller being built around it that includes finite-state automata and PI controller. Simulations implemented in Matlab Simulink software prove the viability and correctitude of the method presented.
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