modelTableData2DLoadDep
Extends from Buildings.Fluid.HeatPumps.ModularReversible.BaseClasses.PartialReversibleRefrigerantMachine.
Information
This is a model for cooling-only or heat recovery chillers where the capacity and power are interpolated from manufacturer data along three variables.
- Evaporator entering or leaving temperature: the choice
between the entering or leaving temperature depends on the
value of the parameter
use_TEvaOutForTabspecified in the parameter record ( Buildings.Fluid.Chillers.ModularReversible.Data.TableData2DLoadDep.Generic). - Condenser entering or leaving temperature: the choice
between the entering or leaving temperature depends on the
value of the parameter
use_TConOutForTabspecified in the parameter record. - Compressor part load ratio (PLR): the part load ratio is used as a proxy variable for the actual capacity modulation observable. A discrete observable such as the number of operating compressors for systems with multiple on/off compressors is converted into a continuous PLR value and the model only approximates the system performance on a time average.
The model includes ideal controls that solve for the CHW or HW supply
or return temperature setpoint within the capacity limit.
The Boolean parameter use_TLoaLvgForCtl is used
for toggling between supply or return temperature control.
The default setting use_TLoaLvgForCtl=true corresponds to
supply temperature control.
For a comprehensive description of the algorithm and the calculations for capacity and power, please refer to the documentation of Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.BaseClasses.TableData2DLoadDep. This documentation also details the required format for the performance data file.
Control points
The following input points are available.
-
Chiller on/off command signal:
on(Boolean, scalar) - For heat recovery chillers only (
have_switchover=true), chiller switchover signal:coo(Boolean, scalar)
Setcoo=truefor cooling mode,coo=falsefor heating mode. -
CHW temperature setpoint:
TChwSet(real, scalar)
This is either the supply or return temperature setpoint depending on the value ofuse_TLoaLvgForCtl. - For heat recovery chillers only (
have_switchover=true), HW temperature setpoint:THwSet(real, scalar)
This is either the supply or return temperature setpoint depending on the value ofuse_TLoaLvgForCtl.
Implementation details
This model introduces structural changes compared to other models within Buildings.Fluid.Chillers.ModularReversible.
First, there is no replaceable heating cycle component.
Instead, the Boolean parameter have_switchover is used
for toggling between cooling-only and heat recovery chillers.
A major implication is that a single performance data file is used
to represent heating and cooling modes in the case of heat recovery
chillers. This data file only provides the maximum cooling heat flow
rate and input power.
Second, the model includes new input variables that match the control points found in chiller onboard controllers (see the previous section for their description).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | have_switchover | false | Set to true for heat recovery chiller with built-in switchover |
| Boolean | use_TLoaLvgForCtl | true | Set to true for leaving temperature control, false for entering temperature control |
| Real | scaFacCoo | refCyc.refCycChiCoo.scaFac | Scaling factor of power and heat flow rate |
| Buildings.Fluid.Chillers.ModularReversible.Data.TableData2DLoadDep.Generic | datCoo | ||
| Modelica.Units.SI.Power | P_min | 0 | Minimum power when system is enabled with compressor cycled off |
| Nominal condition | |||
| Modelica.Units.SI.HeatFlowRate | QCoo_flow_nominal | Nominal cooling capacity | |
| Modelica.Units.SI.Temperature | TEvaCoo_nominal | CHW temperature: leaving if datCoo.use_TEvaOutForTab=true, entering otherwise | |
| Modelica.Units.SI.Temperature | TConCoo_nominal | Condenser cooling fluid temperature: leaving if datCoo.use_TConOutForTab=true, entering otherwise | |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Interfaces.BooleanInput | on | On/off command: true to enable chiller, false to disable chiller | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | TChwSet | CHW temperature setpoint - Supply or return depending on use_TLoaLvgForCtl | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | THwSet | HW temperature setpoint - Supply or return depending on use_TLoaLvgForCtl | |
| Buildings.Controls.OBC.CDL.Interfaces.BooleanInput | coo | Switchover signal: true for cooling, false for heating | |
| Modelica.Blocks.Interfaces.RealOutput | PLR | Compressor part load ratio | |
| Buildings.Fluid.HeatPumps.ModularReversible.BaseClasses.CalculateCommandSignal | calYSet | Calculate command signal from required PLR | |
| Buildings.Controls.OBC.CDL.Logical.Sources.Constant | conCoo | Locks the device in cooling mode if have_switchover=false | |
| Modelica.Blocks.Logical.Not | notCoo | Not cooling is heat recovery | |
| Buildings.Controls.OBC.CDL.Reals.Switch | QUse_flow | Select useful heat flow rate depending on operating mode | |
| Buildings.Templates.Plants.Controls.Utilities.PlaceholderReal | phTHwSet | Placeholder value |
Contents
| Name | Description |
|---|---|
| RefrigerantCycleChillerCooling | Refrigerant cycle module for the cooling mode |
Revisions
-
March 23, 2026, by Antoine Gautier:
Refactored with two separate connectors for CHW and HW temperature setpoints.
This is for #4507. -
March 21, 2025, by Antoine Gautier:
First implementation.