modelCompression

Compression chiller

Extends from Buildings.Templates.Components.Interfaces.PartialChiller.

Information

This is a model for air-cooled or water-cooled compression chillers where the capacity and input power are computed by interpolating manufacturer data along the evaporator entering or leaving temperature, the condenser entering or leaving temperature and the part load ratio. The model can be configured to represent either a cooling-only chiller (have_switchover=false) or a heat-recovery chiller (have_switchover=true) that can be controlled to track either a CHW temperature setpoint or a HW temperature setpoint.

This model is a wrapper for Buildings.Fluid.Chillers.ModularReversible.TableData2DLoadDep, which the user may refer to for the modeling assumptions. Note that, by default, internal safeties in this model are disabled.

Control points

The following input and output points are available.

  • On/off command: y1, DO signal
  • For heat recovery chillers only (have_switchover=true), operating mode command: y1Coo, DO signal, true for cooling, false for heating
  • Supply or return CHW temperature setpoint TChiWatSet, AO signal (the choice between supply and return temperature tracking depends on the parameter: use_TChiWatSupForCtl)
  • For heat recovery chillers only (have_switchover=true), supply or return HW temperature setpoint THeaWatSet, AO signal (the choice between supply and return temperature tracking depends on the parameter: use_TChiWatSupForCtl)
  • Chiller status: y1_actual, DI signal
  • CHW flow request: y1ReqFloChiWat, DI signal
  • (Only if typ=Buildings.Templates.Components.Types.Chiller.WaterCooled) CW flow request: y1ReqFloConWat, DI signal

Model parameters

The design parameters and the chiller performance data are specified with an instance of Buildings.Templates.Components.Data.Chiller.

Components

TypeNameDefaultDescription
Controls.StatusEmulatory1_actualCompute chiller status
Buildings.Controls.OBC.CDL.Routing.BooleanExtractSignalreqFloConWatCompute CW flow request
Buildings.Controls.OBC.CDL.Logical.NotoffReturn true if status is off
Buildings.Controls.OBC.CDL.Logical.TrueDelaydelOffDelay off status
Buildings.Controls.OBC.CDL.Logical.NotreqFloCompute flow request
Buildings.Fluid.Chillers.ModularReversible.TableData2DLoadDepchiChiller

Revisions

  • March 23, 2026, by Antoine Gautier:
    Refactored with two separate connectors for CHW and HW temperature setpoints.
    This is for #4507.
  • April 17, 2025, by Antoine Gautier:
    Refactored with load-dependent 2D table data chiller model.
  • November 18, 2022, by Antoine Gautier:
    First implementation.