| Recent years, building energy consumption is rising continuously, innon-renewable energy is facing depletion , oil prices is rising, these have caused social and government attention on energy efficiency. And designer is continuing efforts to improve building energy efficiency to reduce energy consumption as much as possible. But in fact, many systems of the buildings air conditioning can not be run in accordance with the actual situation for a variety of reasons, there are waste of much energy.The paper takes main-teaching building of Chongqing University as an example. Firstly, to test energy-saving of air-conditioning system and found the system problems, and propose the frequency control to the pumps, cooling towers; secondly, to transform group control system of the engine room, and to optimize the unreasonable self-control for original design; Finally, to re-configurate management system software, to optimize the existing air-conditioning management, and to improve the system efficiency and reliability.This paper is presented to take variable frequency control on the chilled water pump by a differential pressure as to ensure the pump head range in. In part load and improve the energy efficiency potential by analyzing the end demand load and the required head changes. And in the actual project, if using the supply and return water temperature to control the pump frequency for the cooling supply and return water temperature and the folw,it can be to avoid the phenomenon of slow response time when the sub-catchment pump in temperature control,Therefore,the actual variable variable frequency control of the chilled water pump,in a loding rate, it is presented that using the cooling supply and return water temperature to control the pump frequency firstly,and to control by pressure as a auxiliary approach.This paper receives that the relation between inverter and motor efficiency obtained with the speed ratio relation by the test for operating parameters of the cooling water pump and the chilled water pump under frequency control. For variable flow on the impact of chillers, This article focuses on the impact of variable flow of cooling water on the unit, and according to data provided by Carrier, the use of Matlab software fitting, a loading rate, given the chilled water outlet temperature is 6℃, chilled water changes with the load into the same proportion, the unit EER and condenser cooling water flow and water temperature fitting relation, for further study of optimal control of the entire cooling water system provide evidence.The all the influencing factors for the outlet water temperature of the cooling tower are analyzed and compared in this paper.Through field measurement,and the relationship between the entering temperature of the cooling tower and outlet temperature of the cooling tower, the water flow into the tower , air flow into the tower, and the outdoor wet bulb temperature is buit by SPASS software,moreover,this paper explains that the influence level of the various factors for the outlet temperature of the cooling tower using the orthogonal experimental method.For the cooling water system operation control, this paper is discoursed that to pre-set the supply and water different temperature of the tower and the control way of outlet water temperature of the cooling tower (with the difference between the outdoor wet bulb temperature), and the supply and return water temperature of the unit and the power consumption of cooling tower ,unit ,coolong tower is least,then,to the seek the best control way for the outlet water temperature of the cooling tower,and to seek the best outlet temperature by Matlab softwore,finally, the best control method which should be used through comparing the different loading rates.Finally, guiding implementation of energy monitoring systems of the project by analysising control strategies in this paper, and introducing the platform of SCADA energy monitoring system platform based IFX.
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