Research On Energy-efficient Control For Ground Source Heat Pump Based On Model Predictive Control

In recent years,with increasing pressure of global issues,green,environment-friendly,high-efficiency equipment has become the highlight of society.Because of the potential of high COP(Coefficient of performance),GSHP(Ground-source heat pump)is employed in various applications.Compared with conventional air-conditioner,of which the COP is around 2,the COP of GSHP can reach 4 to 5 and significantly decrease the power consumption of HVAC(heating,cooling,air-conditioning)along with Greenhouse gases.In this paper,to promote the efficiency of GSHP,MPC(Model predictive control)is employed to control the ventilation parameters and realizes co-optimization between thermal comfort and power consumption.First,this paper presents the mainstream control methods for GSHP,among which the MPC is reported to be capable of dealing with indoor control problems including non-linearity,disturbances,long delay of indoor temperature.To satisfy the demand of thermal comfort manipulation and stir the potential of MPC,three parts(prediction model,energy consumption model,control strategy)are modified to enhance the overall performance.Prediction model,which is the base of receding process,is directly connected with indoor thermal comfort.Energy model,which provides the power information for optimization,should be set closely to the actual value.The optimization function,which denotes the control strategy of the designer,manipulates the power and thermal comfort conversion.Through a set of GSHP experiments,GSHP running status was recorded and could provide sufficient data for the energy consumption model.Then,PMV(Predicted mean vote)is incorporated as the thermal comfort indicator.Linearization of PMV calculation using MLR(Multi-linear regression)is conducted to meet the requirement of MPC.In optimization part,non-linear power model and PMV indicator are combined to present the actual condition.The result indicates that the employment of MPC and the modification of energy model,thermal-comfort model,optimization function could enhance the control performance of energy consumption and indoor-thermal comfort,which further promote GSHP efficiency.