Design of fast output sampling feedback controller for hyperthermia system via reduced order model

Abstract

This paper describes the design, control and modelling of a fast output sampling feedback control technique for the hyperthermia system via reduced order model. A tumour layer surrounded by muscle layer is modelled in higher-order state space by solving bio heat transfer equation using finite difference method. The reduced model of the higher-order system is obtained using dominant eigenvalue retention and the Davison technique. A stabilising state feedback gain is obtained using aggregation technique from the reduced model. An output feedback gain which realises this state feedback gain is obtained using linear matrix inequality approach. The performance of the controller is evaluated by framing a desired trajectory which meets the goals of the control system. The closed loop and the open loop error norm are validated to prove the efficiency of the controller. This method does not need the states for feedback, and the designed controller placed in closed loop with the original system guarantees the closed loop stability. The closed-loop response of the system with tissue property variation is simulated. The simulated response shows good closed-loop stability.