Abstract
Central air-conditioning system can play an important role in addressing the issue of saving energy in industry. Studies of Industrial Technology Research Institue(ITRI) in Taiwan show the electricity consumption for the central air-conditioning system in electrical mechanics industry at least 25\% of the whole plant. This paper attempts to establish that the empirical dynamic simulation model via big data, and base on the simulation model to find out the optimal variable frequency device(VFD) control strategy for saving energy in the central air-conditioning system. Much of the current literature on this topic pays particular attention to research on sub-system of the real problem like chiller or cooling tower instead of using the system thinking to solve this problem. The results of this paper show that our VFD control strategy can save at least 8\% cost for air-conditioning electricity consumption.