partial model PartialDataCenter "Partial model that impliments cooling system for data centers" replaceable package MediumA = Buildings.Media.Air "Medium model"; replaceable package MediumW = Buildings.Media.Water "Medium model"; // Chiller parameters parameter Integer numChi=2 "Number of chillers"; parameter Modelica.Units.SI.MassFlowRate m1_flow_chi_nominal=34.7 "Nominal mass flow rate at condenser water in the chillers"; parameter Modelica.Units.SI.MassFlowRate m2_flow_chi_nominal=18.3 "Nominal mass flow rate at evaporator water in the chillers"; parameter Modelica.Units.SI.PressureDifference dp1_chi_nominal=46.2*1000 "Nominal pressure"; parameter Modelica.Units.SI.PressureDifference dp2_chi_nominal=44.8*1000 "Nominal pressure"; parameter Modelica.Units.SI.Power QEva_nominal=m2_flow_chi_nominal*4200*(6.67 - 18.56) "Nominal cooling capaciaty(Negative means cooling)"; // WSE parameters parameter Modelica.Units.SI.MassFlowRate m1_flow_wse_nominal=34.7 "Nominal mass flow rate at condenser water in the chillers"; parameter Modelica.Units.SI.MassFlowRate m2_flow_wse_nominal=35.3 "Nominal mass flow rate at condenser water in the chillers"; parameter Modelica.Units.SI.PressureDifference dp1_wse_nominal=33.1*1000 "Nominal pressure"; parameter Modelica.Units.SI.PressureDifference dp2_wse_nominal=34.5*1000 "Nominal pressure"; parameter Buildings.Fluid.Movers.Data.Generic[numChi] perPumCW( each pressure= Buildings.Fluid.Movers.BaseClasses.Characteristics.flowParameters( V_flow=m1_flow_chi_nominal/1000*{0.2,0.6,1.0,1.2}, dp=(dp1_chi_nominal+60000+6000)*{1.2,1.1,1.0,0.6})) "Performance data for condenser water pumps"; parameter Modelica.Units.SI.Time tWai=1200 "Waiting time"; // AHU parameter Modelica.Units.SI.ThermalConductance UA_nominal=numChi*QEva_nominal /Buildings.Fluid.HeatExchangers.BaseClasses.lmtd( 6.67, 11.56, 12, 25) "Thermal conductance at nominal flow for sensible heat, used to compute time constant"; parameter Modelica.Units.SI.MassFlowRate mAir_flow_nominal=161.35 "Nominal air mass flowrate"; parameter Real yValMinAHU(min=0,max=1,unit="1")=0.1 "Minimum valve openning position"; // Set point parameter Modelica.Units.SI.Temperature TCHWSet=273.15 + 8 "Chilled water temperature setpoint"; parameter Modelica.Units.SI.Temperature TSupAirSet=TCHWSet + 10 "Supply air temperature setpoint"; parameter Modelica.Units.SI.Temperature TRetAirSet=273.15 + 25 "Supply air temperature setpoint"; parameter Modelica.Units.SI.Pressure dpSetPoi=80000 "Differential pressure setpoint"; replaceable Buildings.Applications.DataCenters.ChillerCooled.Equipment.BaseClasses.PartialChillerWSE chiWSE( redeclare replaceable package Medium1 = MediumW, redeclare replaceable package Medium2 = MediumW, numChi=numChi, m1_flow_chi_nominal=m1_flow_chi_nominal, m2_flow_chi_nominal=m2_flow_chi_nominal, m1_flow_wse_nominal=m1_flow_wse_nominal, m2_flow_wse_nominal=m2_flow_wse_nominal, dp1_chi_nominal=dp1_chi_nominal, dp1_wse_nominal=dp1_wse_nominal, dp2_chi_nominal=dp2_chi_nominal, dp2_wse_nominal=dp2_wse_nominal, redeclare each Buildings.Fluid.Chillers.Data.ElectricEIR.ElectricEIRChiller_York_YT_1055kW_5_96COP_Vanes perChi, use_strokeTime=false, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, use_controller=false) "Chillers and waterside economizer"; Buildings.Fluid.Sources.Boundary_pT expVesCW( redeclare replaceable package Medium = MediumW, nPorts=1) "Expansion tank"; Buildings.Fluid.HeatExchangers.CoolingTowers.YorkCalc cooTow[numChi]( redeclare each replaceable package Medium = MediumW, each TAirInWB_nominal(displayUnit="degC") = 283.15, each TApp_nominal=6, each energyDynamics=Modelica.Fluid.Types.Dynamics.SteadyStateInitial, each dp_nominal=30000, each m_flow_nominal=0.785*m1_flow_chi_nominal, each PFan_nominal=18000) "Cooling tower"; Buildings.Fluid.Sensors.TemperatureTwoPort TCHWSup( redeclare replaceable package Medium = MediumW, m_flow_nominal=numChi*m2_flow_chi_nominal) "Chilled water supply temperature"; Buildings.BoundaryConditions.WeatherData.ReaderTMY3 weaData(filNam= Modelica.Utilities.Files.loadResource("modelica://Buildings/Resources/weatherdata/USA_CA_San.Francisco.Intl.AP.724940_TMY3.mos")); Buildings.BoundaryConditions.WeatherData.Bus weaBus "Weather data bus"; Buildings.Fluid.Sensors.TemperatureTwoPort TCWSup( redeclare replaceable package Medium = MediumW, m_flow_nominal=numChi*m1_flow_chi_nominal) "Condenser water supply temperature"; Buildings.Fluid.Sensors.TemperatureTwoPort TCWRet( redeclare replaceable package Medium = MediumW, m_flow_nominal=numChi*m1_flow_chi_nominal) "Condenser water return temperature"; Buildings.Fluid.Movers.FlowControlled_m_flow pumCW[numChi]( redeclare each replaceable package Medium = MediumW, each m_flow_nominal=m1_flow_chi_nominal, each addPowerToMedium=false, per=perPumCW, each energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, each use_riseTime=false) "Condenser water pump"; Buildings.Applications.DataCenters.ChillerCooled.Equipment.CoolingCoilHumidifyingHeating ahu( redeclare replaceable package Medium1 = MediumW, redeclare replaceable package Medium2 = MediumA, m1_flow_nominal=numChi*m2_flow_chi_nominal, m2_flow_nominal=mAir_flow_nominal, dpValve_nominal=6000, dp2_nominal=600, mWatMax_flow=0.01, UA_nominal=UA_nominal, addPowerToMedium=false, perFan( pressure(dp=800*{1.2,1.12,1}, V_flow=mAir_flow_nominal/1.29*{0,0.5,1}), motorCooledByFluid=false), yValSwi=yValMinAHU + 0.1, yValDeaBan=0.05, QHeaMax_flow=30000, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, dp1_nominal=30000) "Air handling unit"; Buildings.Fluid.Sensors.TemperatureTwoPort TCHWRet( redeclare replaceable package Medium = MediumW, m_flow_nominal=numChi*m2_flow_chi_nominal) "Chilled water return temperature"; Buildings.Fluid.Sources.Boundary_pT expVesChi( redeclare replaceable package Medium = MediumW, nPorts=1) "Expansion tank"; Buildings.Fluid.Sensors.RelativePressure senRelPre( redeclare replaceable package Medium =MediumW) "Differential pressure"; Buildings.Fluid.Sensors.TemperatureTwoPort TAirSup( redeclare replaceable package Medium = MediumA, m_flow_nominal=mAir_flow_nominal) "Supply air temperature"; Buildings.Examples.ChillerPlant.BaseClasses.SimplifiedRoom roo( redeclare replaceable package Medium = MediumA, rooLen=50, rooWid=30, rooHei=3, m_flow_nominal=mAir_flow_nominal, QRoo_flow=500000, nPorts=2) "Room model"; Buildings.Fluid.Actuators.Valves.TwoWayLinear val[numChi]( redeclare each package Medium = MediumW, each m_flow_nominal=m1_flow_chi_nominal, each dpValve_nominal=6000, each use_strokeTime=false) "Shutoff valves"; Modelica.Blocks.Sources.Constant TCHWSupSet(k=TCHWSet) "Chilled water supply temperature setpoint"; Buildings.Applications.DataCenters.ChillerCooled.Controls.ChillerStage chiStaCon( QEva_nominal=QEva_nominal, tWai=0, criPoiTem=TCHWSet + 1.5) "Chiller staging control"; Modelica.Blocks.Math.RealToBoolean chiOn[numChi] "Real value to boolean value"; Modelica.Blocks.Math.IntegerToBoolean intToBoo( threshold=Integer(Buildings.Applications.DataCenters.Types.CoolingModes.FullMechanical)) "Inverse on/off signal for the WSE"; Modelica.Blocks.Logical.Not wseOn "True: WSE is on; False: WSE is off "; Buildings.Applications.DataCenters.ChillerCooled.Controls.ConstantSpeedPumpStage CWPumCon( tWai=0) "Condenser water pump controller"; Modelica.Blocks.Sources.IntegerExpression chiNumOn( y=integer(sum(chiStaCon.y))) "The number of running chillers"; Modelica.Blocks.Math.Gain gai[numChi]( each k=m1_flow_chi_nominal) "Gain effect"; Buildings.Applications.DataCenters.ChillerCooled.Controls.CoolingTowerSpeed cooTowSpeCon( yMin=0, Ti=60, k=0.1) "Cooling tower speed control"; Modelica.Blocks.Sources.RealExpression TCWSupSet( y=min(29.44 + 273.15, max(273.15 + 15.56, cooTow[1].TAir + 3))) "Condenser water supply temperature setpoint"; Modelica.Blocks.Sources.Constant TAirSupSet(k=TSupAirSet) "Supply air temperature setpoint"; Buildings.Applications.BaseClasses.Controls.VariableSpeedPumpStage varSpeCon( tWai=tWai, m_flow_nominal=m2_flow_chi_nominal, deaBanSpe=0.45) "Speed controller"; Modelica.Blocks.Sources.RealExpression mPum_flow( y=chiWSE.port_b2.m_flow) "Mass flowrate of variable speed pumps"; Buildings.Controls.Continuous.LimPID pumSpe( Ti=40, yMin=0.2, k=0.1) "Pump speed controller"; Modelica.Blocks.Sources.Constant dpSetSca(k=1) "Scaled differential pressure setpoint"; Modelica.Blocks.Math.Product pumSpeSig[numChi] "Pump speed signal"; Buildings.Controls.Continuous.LimPID ahuValSig( Ti=40, reverseActing=false, yMin=yValMinAHU, k=0.01) "Valve position signal for the AHU"; Modelica.Blocks.Math.Product cooTowSpe[numChi] "Cooling tower speed"; Buildings.Controls.Continuous.LimPID ahuFanSpeCon( k=0.1, reverseActing=false, yMin=0.2, Ti=240) "Fan speed controller "; Modelica.Blocks.Sources.Constant TAirRetSet(k=TRetAirSet) "Return air temperature setpoint"; Utilities.Psychrometrics.X_pTphi XAirSupSet(use_p_in=false) "Mass fraction setpoint of supply air "; Modelica.Blocks.Sources.Constant phiAirRetSet(k=0.5) "Return air relative humidity setpoint"; Modelica.Blocks.Math.Gain gai1(k=1/dpSetPoi) "Gain effect"; Buildings.Controls.OBC.CDL.Reals.Switch swi[numChi] "Switch to assign pump signal if plant is on"; Buildings.Controls.OBC.CDL.Logical.Or plaOn "Output true if plant is on"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant zer[numChi](each final k=0) "Outputs zero"; Modelica.Blocks.MathBoolean.Or chiOnSta(nu=numChi) "Output true if at least one chiller is on"; equation connect(chiWSE.port_b2, TCHWSup.port_a); connect(chiWSE.port_b1, TCWRet.port_a); for i in 1:numChi loop connect(TCWSup.port_a, cooTow[i].port_b); connect(pumCW[i].port_a, TCWSup.port_b); connect(TCWRet.port_b, val[i].port_a); connect(weaBus.TWetBul, cooTow[i].TAir); end for; connect(senRelPre.port_b, ahu.port_b1); connect(cooTow.port_a, val.port_b); connect(TCWRet.port_b, expVesCW.ports[1]); connect(ahu.port_b1, expVesChi.ports[1]); connect(chiWSE.port_b2, TCHWSup.port_a); connect(chiWSE.port_b1, TCWRet.port_a); for i in 1:numChi loop connect(TCWSup.port_a, cooTow[i].port_b); connect(pumCW[i].port_b, chiWSE.port_a1); connect(chiOn[i].y, chiWSE.on[i]); connect(cooTowSpeCon.y, cooTowSpe[i].u1); end for; connect(chiStaCon.y, chiOn.u); connect(intToBoo.y, wseOn.u); connect(wseOn.y, chiWSE.on[numChi + 1]); connect(CWPumCon.y, gai.u); connect(TCWSupSet.y, cooTowSpeCon.TCWSupSet); connect(TCHWSupSet.y, cooTowSpeCon.TCHWSupSet); connect(TCWSup.T, cooTowSpeCon.TCWSup); connect(TCHWSup.T, cooTowSpeCon.TCHWSup); connect(chiWSE.TSet, TCHWSupSet.y); connect(mPum_flow.y, varSpeCon.masFloPum); connect(senRelPre.port_a, ahu.port_a1); connect(pumSpe.y, varSpeCon.speSig); connect(dpSetSca.y, pumSpe.u_s); connect(pumSpe.y, pumSpeSig[1].u2); connect(pumSpe.y, pumSpeSig[2].u2); connect(varSpeCon.y, pumSpeSig.u1); connect(TAirSupSet.y, ahuValSig.u_s); connect(TAirSup.port_a, ahu.port_b2); connect(TAirSup.T, ahuValSig.u_m); connect(ahuValSig.y, ahu.uVal); connect(TAirSupSet.y, ahu.TSet); connect(CWPumCon.y, val.y); connect(CWPumCon.y, cooTowSpe.u2); connect(cooTowSpe.y, cooTow.y); connect(TCHWRet.port_a, ahu.port_b1); connect(chiNumOn.y, CWPumCon.numOnChi); connect(ahu.port_a2, roo.airPorts[1]); connect(roo.airPorts[2], TAirSup.port_b); connect(roo.TRooAir, ahuFanSpeCon.u_m); connect(TAirRetSet.y, ahuFanSpeCon.u_s); connect(phiAirRetSet.y, XAirSupSet.phi); connect(XAirSupSet.X[1], ahu.XSet_w); connect(TAirRetSet.y, XAirSupSet.T); connect(ahuFanSpeCon.y, ahu.uFan); connect(gai1.y, pumSpe.u_m); connect(gai1.u, senRelPre.p_rel); connect(weaData.weaBus, weaBus); connect(chiOnSta.u, chiOn.y); connect(chiOnSta.y, plaOn.u1); connect(wseOn.y, plaOn.u2); connect(zer.y, swi.u3); for i in 1:numChi loop connect(plaOn.y, swi[i].u2); end for; connect(swi.y, pumCW.m_flow_in); connect(gai.y, swi.u1); connect(plaOn.y, varSpeCon.on); connect(plaOn.y, CWPumCon.on); end PartialDataCenter;

partial model PostProcess "Post-processing" Buildings.Utilities.Math.IntegratorWithReset FCTim "Free cooling time"; Modelica.Blocks.Sources.RealExpression freCooSig "Free cooling signal"; Modelica.Blocks.Sources.RealExpression parMecCooSig "Partial mechanic cooling signal"; Buildings.Utilities.Math.IntegratorWithReset PMCTim "Partial mechanic cooling time"; Buildings.Utilities.Math.IntegratorWithReset FMCHou "Full mechanic cooling time"; Modelica.Blocks.Sources.RealExpression fulMecCooSig "Full mechanic cooling signal"; Modelica.Blocks.Sources.RealExpression PHVAC "Power consumed by HVAC system"; Modelica.Blocks.Sources.RealExpression PIT "Power consumed by IT"; Modelica.Blocks.Continuous.Integrator EHVAC( initType=Modelica.Blocks.Types.Init.InitialState, y_start=0) "Energy consumed by HVAC"; Modelica.Blocks.Continuous.Integrator EIT( initType=Modelica.Blocks.Types.Init.InitialState, y_start=0) "Energy consumed by IT"; Modelica.Blocks.Math.IntegerChange sigCha( u(start=0, fixed=true)) "Signal changes"; Modelica.Blocks.MathInteger.TriggeredAdd swiTim "Triggered addition"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt(k=1) "Unit signal"; equation connect(freCooSig.y,FCTim. u); connect(parMecCooSig.y,PMCTim. u); connect(fulMecCooSig.y, FMCHou.u); connect(PHVAC.y,EHVAC. u); connect(PIT.y,EIT. u); connect(sigCha.y, swiTim.trigger); connect(conInt.y, swiTim.u); end PostProcess;