modelHeatPumpDHWTank
Base subsystem with water-to-water heat pump with storage tank for domestic hot water
Extends from Buildings.DHC.ETS.Combined.Subsystems.BaseClasses.PartialHeatPump.
Information
Model of a water-to-water heat pump with temperature control on evaporator side, with the heat pump being connected to a domestic hot water tank with fresh water stations.
The heat pump model with storage tank is described in Buildings.DHC.Loads.HotWater.StorageTankWithExternalHeatExchanger. The evaporator hydronics and control are described in Buildings.DHC.ETS.Combined.Subsystems.BaseClasses.PartialHeatPump.
Condenser Controls
The system is enabled when the tank charge control signal switches to
true.
When enabled,
- the condenser pump is commanded on and supplies the nominal mass flow rate to the tank and domestic hot water system,
-
the heat pump evaporator supplies a constant temperature increase from the return to
the supply equal to
dT_nominal.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.DHC.Loads.HotWater.Data.GenericDomesticHotWaterWithHeatExchanger | datWatHea | Performance data | |
| Nominal condition | |||
| Modelica.Units.SI.HeatFlowRate | QHotWat_flow_nominal | Nominal capacity of heat pump condenser for hot water production system (>=0) | |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Conversions.BooleanToReal | floCon | Condenser mass flow rate | |
| Buildings.DHC.Loads.HotWater.StorageTankWithExternalHeatExchanger | heaPumTan | Heat pump with storage tank for domestic hot water | |
| Buildings.Controls.OBC.CDL.Reals.Sources.Constant | THotSouSet | Set point of water in hot water tank | |
| Buildings.Fluid.Sources.Boundary_pT | preRef | Reference pressure for loop | |
| Buildings.Fluid.Sensors.TemperatureTwoPort | senTemHeaPumRet | Sensor for return temperature to heat pump | |
| Buildings.Controls.OBC.CDL.Reals.AddParameter | addPar | dT for heater | |
| Modelica.Blocks.Math.Add | addPPum1 | Electricity use for pumps | |
| Buildings.Controls.OBC.CDL.Logical.And | and2 | Outputs true if boiler needs to be charged and plant is enabled |
Revisions
-
July 10, 2024, by Michael Wetter:
Enabled input filter to the pumps to avoid a nonlinear system of equations that causes OpenModelica to stop the translation.
This is for issue 3924. -
June 11, 2024, by Michael Wetter:
Changed temperature sensor to not allow reverse flow as it is not needed and will cause an undefined output if the mass flow rate is zero, which causes issues in the result verification.
This is for issue 3876. -
November 28, 2023, by David Blum:
First implementation, extended from partial base class with added condenser hydronics and control. This is for issue 3063.