Analysis On Control Strategies For Heat Pump Air Condition System With Hybrid Of Cooling Tower And Ground Source

With the development of the society,energy production hasn't been more and more keep up with the consumption of energy.Building energy consumption has gradually become one of the main energy consumption,in which HVAC energy consumption can be a major part.In the aspects of energy-saving and environmental protection.Heat pump technology has great prospects,because of Energy saving,environmental protection,high efficiency.The Chengdu belong to Hot Summer and Cold Winter Zone,and the building cooling load is much large than heating load.GHSP system has a problem of soil heat accumulation,which soil is cold source only.This problem will cause heat pump's operation efficiency reduce and energy consumption increase.The hybrid ground source heat pump systems with cooling tower and ground heat exchanger has been widely applied.In the hybrid ground source heat pump system,Control the cooling tower is the main measures to reduce soil heat accumulation and efficient operation for a long time.In this paper,an office building in Chengdu was selected for study.The building's load was computed using DEST.Best on it,the hybrid ground source heat pump system was designed.And then,the model of hybrid ground source heat pump system has been built in Trnsys.The different control strategies including different temperature control /highest temperature control and control by stages were simulation.The different temperature control and highest temperature control is used in The middle of control by stages.Six control points in four control strategies has been analyzed.This paper evaluates the control strategy from the aspects of running energy consumption,soil heat accumulation and performance coefficient.And then,find the optimal control point of the strategies.Simulation results show that The optimum working point is 28 ? when control strategy choose different temperature control and middle of control by stages.The optimum working point is 2? when control strategy choose highest temperature control and middle of control by stages.the problem of the soil heat accumulation can be alleviated when the control strategy choose control by stages.The increase of soil's biggest average temperature was minimum when the control strategy choose highest temperature control in control by stages and the operating cost is the lowest when the control strategy choose different temperature control in control by stages.