Research on Fuzzy Regulation Strategies in the Constant Air Volume Air Conditioning System

Abstract

The energy consumption of the constant air volume (CAV) system largely depends on the regulation strategies. Although some air conditioning systems are equipped with automatic regulation devices, others lack effective regulation strategies. To avoid wasting energy and presenting simple regulation methods, fuzzy regulation strategies for CAV systems are studied in this research. A CAV system of an office building is modeled and simulated with the Designer's Simulation Toolkit (DeST). The operating parameters are calculated based on the instantaneous load obtained from simulation. The operation of the system is divided into five stages according to different conception of “cold” or “hot” in different seasons. The relationship between the outdoor air temperature and the fresh air volume, and the supply air temperature is presented in the form of fuzzy rules. Then the building is simulated under different load conditions and the operating parameters are obtained from fuzzy reasoning. Finally, the effect of fuzzy strategies on energy consumption is analyzed and compared with the effects of the operating parameters obtained from simulation. The results show that energy consumption using a fuzzy regulation strategy is close to the energy consumption of knowing the exact load of the building, while the fuzzy regulation strategy can largely simplify the regulation of the air conditioning system.