Temperature regulation and tracking in a MIMO system with a mobile heat source by LQG control with a low order model

A multi-input multi-output (MIMO) thermal control problem in real-time is investigated. An aluminum slab is heated on one side by a mobile radiative heat source and cooled on the other side by a fan panel. Starting from a nominal steady state configuration of heat power, source position and ventilation level, the objective is to control temperature at 3 chosen locations on the rear side when the nominal ventilation level is subject to disturbances. The main features of this paper are: (i) the use of the heat source power and its displacements in both directions along the plate as actuators, which is the principal originality of this work, (ii) the use of a low order model identified from experimental data by the Modal Identification Method to perform state feedback control in real time (t=2 s) through a Linear Quadratic Gaussian (LQG) compensator, instead of a (large-size) heat transfer model, and (iii) the study of the effect of the control time period, the LQG parameters and the order of the model. Both thermal regulation and tracking problems have been addressed. Results show promising future developments involving more actuators and controlled outputs.