Intake power measurement as a criterion for control of HVAC systems

¹ Wrocław University of Science and Technology, Department of Air Conditioning, Heating, Gas Engineering and Air Protection, ul. Norwida 4/6, Building C-6, 50-373 Wrocław, Poland
² Max Fordham, St Andrew's House, 59 St Andrew's St, CB2 3BZ, Cambridge, UK

^* Corresponding author: juliusz.walaszczyk@pwr.edu.pl

Abstract

Under certain conditions, a HVAC system may consume less energy, provided that the initial response to the increasing heat gains is the increase in the airflow, while cooling is delayed. This ensures that the energy for cooling and reheat is reduced, while the fan power increases. Note that it is difficult to develop the following approach in the standard sequential control algorithms. On the other hand, the use of more complex algorithms than standard sequential algorithms is generally not encouraged because of the increase in the complexity of the control system and its resistance to respond to the varying parameters of a HVAC system. In this work, therefore, to avoid the following complications, the Intake Power Optimization algorithm is proposed. The Intake Power optimization algorithm is compared to the two sequential algorithms: Air conditioning and Airflow priority. To create the reference point enabling comparisons of the three strategies, the optimal control was established using the Nelder-Mead method. It is shown that the Intake power optimization algorithm provides a better control than the sequential algorithms and almost exclusively performs the optimal control actions. As an aside, the results indicate that the same heat gains, however, evenly distributed between rooms may contribute to the significant reduction of the energy demand.