Application of PLC Control System with Fuzzy Algorithm on Thermal Comfort of HVAC

• Main Authors: Yan-De Jiang, 江衍德
• Other Authors: 張永宗
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/268296

碩士 === 國立臺北科技大學 === 能源與冷凍空調工程系碩士班 === 99 === Climate change and the greenhouse effect have caused the average summer temperature to increase year by year, and the use of air-conditioning equipment during summer has become inevitable. Air-conditioning systems in houses, offices, schools, factories, hospitals and laboratories have become inseparable in our daily life and working place. Since the air conditioner is used for a long period of time during summer, inappropriate control of the air-conditioning system often leads to unnecessary energy consumption. Unnecessary unloading or shutting down the air-conditioning system in order to save energy may also make individuals feel uncomfortable or even damage their health. The air side of the chilled water air-conditioning system is the focus of this study. The fuzzy control system that consists of fuzzy algorithm and PLC is used to regulate the operating frequencies of the blower and zone pump (chilled water) in the air handling unit to allow the unit to supply cold air and change the indoor temperature and humidity. According to ASHRAE Standard 55, PMV (Predicted Mean Vote) is used to express the environment in which individuals feel the most comfortable, which is between -0.5 and 0.5. When the air-conditioning system is operating, a higher PMV value in the air-conditioned region indicates a more energy-saving air-conditioning system. Therefore, the PMV value of the fuzzy control system is set to 0.5 in this study in order to make the air-conditioning system operate efficiently without overlooking human comfort. The experimental results show that the fuzzy control system proposed in this study can efficiently keep the PMV value in the air-conditioned region at 0.5 and effectively reduce the operating power consumption of the blower and zone pump (chilled water) in the air handling unit.