Modeling and Control of Indoor Climate Using a Heat Pump Based Floor Heating System

Modeling and control of an indoor climate using a floor heating system based on a heat pump is discussed. The thermodynamic models of the heat pump, room, floor and circulated water are theoretically developed and then identified through experimental data. Several control strategies, namely relay control, P control, PID control and PID control with pre-filtering of reference input, are developed and simulated based on the developed system model. The simulation results turn out that the PID control with pre-filtering strategy generated the best system performance in terms of the smallest overshoot, fast response, highest COP in the transient period, and the smallest deviation and the least sensitivity to disturbance in the steady period. Meanwhile, this strategy also uses least power compared with other strategies. Instead of using the standard relay control, this study reveals a huge potential to use advanced control techniques to optimize operation of this kind of thermal system from thermal comfort and energy consumption perspectives.