Optimization of the operation of an air-conditioning system by means of a distributed control system

A control scheme for an air conditioning system is proposed, based on the continuous monitoring of the thermal, electric and climate variables. The dynamic behavior of the relevant variables is determined and expressed in terms of a compact model (the system transfer function). In this study, the indoor temperature control loop has been implemented using a conventional PI algorithm. The controller varies the speed of the compressor motor by means of a frequency inverter, which, in its turn, controls the refrigeration load. It has been observed that the PI controller reduced the variation of the indoor temperature, with significant improvement in the comfort conditions and reduction in the energy consumption. The derived model proved to be suitable for this type of application. Other dynamic important characteristics of the building and of the airconditioning equipment have been highlighted. The information contained in this model could also be useful for new design and retrofitting.