block OptimalStartCalculation "Base class for the block OptimalStart" parameter Real tOptMax( final quantity="Time", final unit="s") "Maximum optimal start time"; parameter Real thrOptOn( final quantity="Time", final unit="s") "Threshold time for the output optOn to become true"; parameter Integer nDay "Number of previous days for averaging the temperature slope"; parameter Real uLow( final quantity="TemperatureDifference", final unit="K") "Threshold to determine if the zone temperature reaches the occupied setpoint, should be a non-negative number"; parameter Real uHigh( final quantity="TemperatureDifference", final unit="K") "Threshold to determine the need to start the HVAC system before occupancy, should be greater than uLow"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TDif( final quantity="TemperatureDifference", final unit="K") "Difference between zone setpoint and measured temperature, must be bigger than zero for heating and cooling if setpoint is not yet reached"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput staCal "Start calculation"; Buildings.Controls.OBC.CDL.Interfaces.RealInput tNexOcc( final quantity="Time", final unit="s", displayUnit="h") "Time until next occupancy"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput tOpt( final quantity="Time", final unit="s", displayUnit="h") "Optimal start time of HVAC system"; Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput optOn "Optimal start boolean output"; protected constant Real tReaMin( final quantity="Time", final unit="s", displayUnit="h")=120 "Minimum value for optimal start time if the system reached the set point almost immediately (used to avoid division by zero)"; constant Real temSloDef( final quantity="TemperatureSlope", final unit="K/s")=1/3600 "Minimum value for temperature slope (used to avoid division by zero)"; Buildings.Controls.OBC.CDL.Logical.Sources.SampleTrigger samTri( final period=86400, final shift=0) "Trigger that triggers each midnight"; Buildings.Controls.OBC.CDL.Discrete.TriggeredMovingMean samTemSloAve( final n=nDay) "Calculate the averaged temperature slope over the past n days"; Buildings.Controls.OBC.CDL.Discrete.TriggeredSampler dTCalOn "Get the sampled temperature difference at the same time each day"; Buildings.Controls.OBC.CDL.Discrete.TriggeredSampler dTHVACOn "Get the temperature difference when the HVAC system starts"; Buildings.Controls.OBC.CDL.Continuous.Sources.Constant con( final k=0) "Deadband case"; Buildings.Controls.OBC.CDL.Continuous.Sources.Constant timReaMin( final k=tReaMin) "Minimum time to reach set point (used to avoid division by zero)"; Buildings.Controls.OBC.CDL.Continuous.Sources.Constant defTemSlo( final k=temSloDef) "Default temperature slope in case of zero division"; Buildings.Controls.OBC.CDL.Logical.Edge edg "HVAC start time"; Buildings.Controls.OBC.CDL.Logical.FallingEdge falEdg "The instant when the zone temperature reaches setpoint"; Buildings.Controls.OBC.CDL.Continuous.Hysteresis hys( final uLow=uLow, final uHigh=uHigh) "Comparing zone temperature with zone setpoint"; Buildings.Controls.OBC.CDL.Continuous.Hysteresis hysOpt( final pre_y_start=false, final uHigh=0, final uLow=-60) "Hysteresis to activate the optimal start"; Buildings.Controls.OBC.CDL.Continuous.Sources.Constant maxStaTim( final k=tOptMax) "Maximum optimal start time"; Buildings.Controls.OBC.CDL.Logical.TrueHoldWithReset truHol( final duration=tOptMax+11*3600) "Hold the start time for timer"; Buildings.Controls.OBC.CDL.Continuous.Divide temSlo "Calculate temperature slope"; Buildings.Controls.OBC.CDL.Logical.Pre pre "Break algebraic loops"; Buildings.Controls.OBC.CDL.Continuous.Subtract sub1 "Calculate the time duration to reach the setpoint"; Buildings.Controls.OBC.CDL.Continuous.Subtract sub2 "Calculate differential between time-to-next-occupancy and the cool-down time"; Buildings.Controls.OBC.CDL.Continuous.Min min "Get the final optimal start time"; Buildings.Controls.OBC.CDL.Discrete.TriggeredSampler triSam "The instant when the zone temperature reaches setpoint with maximum time cutoff"; Buildings.Controls.OBC.CDL.Discrete.TriggeredSampler triSam1 "Record the start time when the HVAC system is turned on"; Buildings.Controls.OBC.CDL.Logical.Latch lat "Stop calculation when the zone temperature reaches setpoint"; Buildings.Controls.OBC.CDL.Logical.Timer tim "Record time duration for the zone temperature to reach setpoint"; Buildings.Controls.OBC.CDL.Logical.Not not1 "Becomes true when the setpoint is reached"; Buildings.Controls.OBC.CDL.Continuous.Divide tOptCal "Calculate optimal start time using the averaged previous temperature slope"; Buildings.Controls.OBC.CDL.Discrete.TriggeredSampler samTimOpt "Get the sampled optimal start time at the same time each day"; Buildings.Controls.OBC.CDL.Continuous.GreaterThreshold greThr( final t=thrOptOn) "The threshold for optOn signal becomes true"; Buildings.Controls.OBC.CDL.Logical.And and2 "Logical and"; Buildings.Controls.OBC.CDL.Continuous.Max timRea "Time required to reach the set point"; Buildings.Controls.OBC.CDL.Continuous.Max temSloAve "Temperature slope during heat up or cool down over the past sampled days"; Buildings.Controls.OBC.CDL.Continuous.Switch dTUse "dT used in the calculations (to avoid negative dT)"; Buildings.Controls.OBC.CDL.Continuous.GreaterThreshold reqStaUp( final t=0, final h=0) "Output true if optimal startup is needed"; Buildings.Controls.OBC.CDL.Logical.And triAve "Trigger sampling but only if optimal start up is needed"; equation connect(tim.y,triSam.u); connect(falEdg.y,triSam.trigger); connect(not1.y,lat.clr); connect(temSlo.y,samTemSloAve.u); connect(TDif,hys.u); connect(staCal,dTCalOn.trigger); connect(TDif,dTHVACOn.u); connect(pre.y,dTHVACOn.trigger); connect(pre.y,lat.u); connect(edg.y,triSam1.trigger); connect(triSam1.y,sub1.u2); connect(triSam.y,sub1.u1); connect(TDif,dTCalOn.u); connect(tNexOcc,sub2.u2); connect(sub2.y,hysOpt.u); connect(min.y,sub2.u1); connect(staCal,truHol.u); connect(truHol.y,tim.u); connect(tim.y,triSam1.u); connect(min.y,tOpt); connect(not1.u,hys.y); connect(lat.y,edg.u); connect(lat.y,falEdg.u); connect(tOptCal.y,samTimOpt.u); connect(staCal,samTimOpt.trigger); connect(dTHVACOn.y,temSlo.u1); connect(min.y,greThr.u); connect(hysOpt.y,and2.u2); connect(greThr.y,and2.u1); connect(and2.y,pre.u); connect(pre.y,optOn); connect(timRea.y,temSlo.u2); connect(timRea.u1,sub1.y); connect(temSloAve.y,tOptCal.u2); connect(temSloAve.u1,samTemSloAve.y); connect(defTemSlo.y,temSloAve.u2); connect(min.u1,samTimOpt.y); connect(maxStaTim.y,min.u2); connect(reqStaUp.u,dTCalOn.y); connect(dTUse.u2,reqStaUp.y); connect(dTCalOn.y,dTUse.u1); connect(con.y,dTUse.u3); connect(dTUse.y,tOptCal.u1); connect(triAve.u2,samTri.y); connect(reqStaUp.y,triAve.u1); connect(triAve.y,samTemSloAve.trigger); connect(timReaMin.y, timRea.u2); end OptimalStartCalculation;