Abstract
This paper outlines the basic principle of a predictive control system, and shows how this can be used for controlling temperature set-back in buildings where a heat pump is an integrated part of the heating system.
Because of the heat pump’s distinctive character, it sets special requirements for the control system to save exergy. The predictive controller satisfies these requirements, and takes, unlike traditional bang-bang control, into account the heat pump’s capability to conserve exergy.
Process knowledge in the form of a dynamic mathematical model is integrated in the controller, and an optimization algorithm finds the control trajectory that minimize the cost of exergy consumption. The Kuhn-Tucker conditions verify a strong active constraint which consists of a maximum utilization of the heat pump, and a minimum utilization of the auxiliary heater. This result can be used to simplify both the solution of the optimization problem, and the mathematical model.
Different control structures are compared regarding exergy consumption, and it is shown how these control structures influence the various exergy losses in the heating system.
A sensitivity analysis is performed, where different process parameters such as heat exchanger areas, thermal capacity of the building and part load efficiency of the compressor, are varied. It is shown how these perturbations influence the optimal control trajectory.
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© 1991 Springer-Verlag Berlin Heidelberg
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Svensson, C. (1991). Predictive Control of a Hybrid Heating System Including a Heat Pump. In: Smith, I.E. (eds) Applications and Efficiency of Heat Pump Systems. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-662-30179-1_16
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DOI: https://doi.org/10.1007/978-3-662-30179-1_16
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-662-30181-4
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