Adaptive optimal control of seawater cooling system in centralized air-conditioning system

Abstract

在淡水缺乏的香港地区,中央空调系统通常采用海水进行冷却。在能源日益紧张的今天,对空调系统进行优化控制是提高能源效率及节省能源的一个重要途径。本文针对中央空调海水冷却系统提出了根据海水冷却水压力设定值调整的微分自适应优化控制方法实现空调系统能耗最小化,然后进一步对该自适应控制方法进行了基于模拟环境的实验验证。结果表明该方法可以降低系统能耗,提高能源使用效率。 Seawater is usually used to cool down condensers in centralized air-conditioning systems in Hong Kong where the fresh water is very scarce.Optimal control is among the means to improve energy efficiency in air-conditioning system.This paper presents an adaptive optimal control strategy to optimize the seawater pressure set-point of variable-speed seawater pumps aiming at minimal energy consumptions.This optimization is achieved by adjusting the pressure set-point according to the estimated derivative of the total power with respect to seawater pressure differential.This strategy is validated using simulations.The tests show that significant saving in the overall energy consumption of the chilling system can be achieved by properly resetting the pressure set-point only.