Project and experimental testing of the control system of an air-conditioning plant

In this paper, the initial considerations and the first results of the development of the supervision system for the air-conditioning plant of the testing station with variable orientation of the Mechanical Engineering Department of the University of Calabria are presented. This station is provided with the air-conditioning plant able to operate with air and water for cooling and heating; the heating plant using hot water supplies different terminals, including the radiator, fancoil and radiant floor. The plant is endowed with the flexibility to allow opportune analyses of the performances and of consumption by varying the control action. This first study phase attempts to identify the best match among the plant types and the control systems, on the basis of experimental data obtained for the different control actions, with the aim of providing useful indications to the designer. For the testing station plant, the optimum control action proved to be the proportional-integral-derivative (PID) one. The instruments used, thanks to the ease of implementation and flexibility, enabled the realisation of a control system guaranteeing good plant performances. Moreover, the software developed makes an intuitive graphic display possible of the plant situation at any moment.