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E. Luchini, D. Radler, D. Ritzberger, S. Jakubek, M. Kozek:
"Model predictive temperature control and ageing estimation for an insulated cool box";
Applied Thermal Engineering, 144 (2018), 269 - 277.

The transport of perishable goods in insulated cool boxes (ICB) is affected by strong disturbances and requires an
effective temperature control scheme. Model predictive control (MPC) can provide such a performing control
scheme, however, the strong disturbance of irradiation by the sun can be rarely measured. Furthermore, the
ageing of the ICB´s insulation is a parameter of vital interest for logistic and economic planning although it
cannot be directly measured. In this work a MPC and a custom disturbance observer is presented, which provide
an estimate of the current irradiation and the ageing state, respectively. This is obtained by first estimating the
excess heat loss of the ICB, and then splitting up this heat loss into an irradiation part and a part due to ageing of
the ICB´s insulation. The ageing model is assumed to be parametric, and a nonlinear estimation scheme is
employed for parameter tuning. A suitable MPC formulation guarantees offset-free tracking of the desired
temperature. The performance of the overall concept is demonstrated in a simulation for the nominal case, for
increasing measurement noise, and for an abrupt change in the ageing parameters. Additionally, a non-parametric
estimate for the confidence interval of the end-of-life prediction of the ICB is given.

Refrigeration system, Model predictive control, Disturbance observer, Estimation of ageing process, Nonlinear ageing estimation

http://dx.doi.org/10.1016/j.applthermaleng.2018.08.045