Improving Heat Transfer Efficiency in Heating Ventilation and Air Conditioning Systems Using a Robust Fuzzy PID Controller

High levels of measurement noise, nonlinear and non minimum phase, and conflicting performance requirements pose challenging problems for improving heat transfer efficiency and flow control in HVAC systems. This paper extends the theoretical development of the Energy Delivery Efficiency (EDE) concept to include supply air latent effects and economizer operation, defines how ideal HVAC systems should be operated and controlled so that energy use is minimized while meeting required outdoor ventilation flow, and evaluates the extent to which heating and cooling energy use of such ideal HVAC systems. A new controller, based on fuzzy PID controller is presented, to be used to control heating systems in intermittently occupied buildings. Comparisons with classical control methods demonstrate that the proposed fuzzy PID controller gave superior results in terms of the control and optimization of the recovery time after setback. For each case, the differences in comfort and energy consumption between the different types of room were studied.