Temperature and humidity control for an automobile during heating period

This paper investigates a control strategy for automobile climate control (ACC) problem; in particular, the heating mode in winter is considered when the initial car compartment temperature and outside temperature are colder than comfortable. By analyzing the air conditioning processes involving the automobile air-handling unit operating at various weather conditions on a psychrometric chart, a control strategy is developed based upon the concept of conservation of sensible heat and latent heat. Irrespective of the car compartment´s initial condition, the control strategy is to control air flow and mixed air temperature such that the compartment conditions in terms of temperature and humidity reach a setting condition. The proposed strategy is composed of two parts: air mass flow rate and the percentage of heating air flow. In short, balancing the sensible heat transfer among the air condition processes is essential to achieving temperature control, as variation in the net sensible heat will lead to changes in temperature. The proposed control strategy is evaluated in a Matlab/Simulink simulation environment, which shows the proposed control strategy performs better when compared to traditional fuzzy control.