Energy Saving Measures and Control Programming for Combined Air Conditioning System

The reliability and stability of PLC controlled air conditioning system in cigarette enterprises were directly affected by PLC programming.The structure and principle of combined air conditioning system were analyzed,and two energy saving measures adoptable in PLC programming were proposed:maximizing the use of outdoor fresh air as a cold source and adjusting the frequency of intake fan driving motor based on input air temperature difference instead of input air pressure.Moreover,the principle of automatic temperature and humidity regulation and control measures for PID self-adaptive control and cascade control of air conditioning system were discribed.The practical application showed that the two measures could save energy by about 8% with reliable performance and meet the requirements of indoor environment in production workshop.