modelController

Define current operation mode

Extends from Modelica.Blocks.Icons.Block (Basic graphical layout of input/output block).

Information

The CHP plant switches between six possible operating modes depending on the current mode, control signals and plant boundary conditions. The regular transition between them is as follows:

  • off
  • stand-by mode
  • pump-on mode
  • warm-up mode
  • normal operation
  • cool-down mode
  • off or stand-by mode

Switching between operating modes

From the off mode:

  • The transition from the off to the stand-by mode will occur when the plant availability signal avaSig becomes true.

From the stand-by mode:

  • The transition from the stand-by to the pump-on mode will occur when the plant running signal runSig becomes true.
  • If avaSig becomes false, the CHP will automatically change to the off mode.

From the pump-on mode:

  • The transition from the pump-on to stand-by mode will occur after the specified time delay and if the water flow rate mWat_flow is greater than the minimum mWatMin_flow.
  • If runSig becomes false, the CHP will automatically change to the off mode.

From the warm-up mode:

  • The transition from the warm-up mode to the normal operation will occur after the specified time delay (if warmUpByTimeDelay is true) or when the engine temperature TEng becomes higher than the nominal temperature TEngNom (if warmUpByTimeDelay is false).
  • If runSig becomes false or if the water flow rate mWat_flow becomes less than the minimum mWatMin_flow, the CHP will automatically change to the cool-down mode.

From the normal mode:

  • The transition from the normal operation to the cool-down mode will occur when runSig becomes false or if the water flow rate mWat_flow becomes less than the minimum mWatMin_flow.

From the cool-down mode:

  • The transition from the cool-down mode will occur after the specified time delay. If avaSig is true, the CHP will change to the stand-by mode; else, it will change to the off mode.
  • If the CHP has the mandatory cool-down configuration (if coolDownOptional is false), the plant has to complete the cool-down period before it can be reactivated. If the CHP has the optional cool-down configuration (if coolDownOptional is true), the plant may imediatelly change to the warm-up mode if it gets reactivated (runSig= true).

Parameters

TypeNameDefaultDescription
Buildings.Fluid.CHPs.Data.GenericperPerformance data
Dynamics
Modelica.Units.SI.TimewaitTime60Wait time before transition from pump-on mode fires

Connectors

TypeNameDefaultDescription
Buildings.Controls.OBC.CDL.Interfaces.BooleanInputavaSigTrue when the plant is available
Buildings.Controls.OBC.CDL.Interfaces.BooleanInputrunSigTrue when plant should run
Buildings.Controls.OBC.CDL.Interfaces.RealInputmWat_flowCooling water mass flow rate
Buildings.Controls.OBC.CDL.Interfaces.RealInputTEngEngine temperature
Buildings.Controls.OBC.CDL.Interfaces.RealInputPEleNetNet power output
Buildings.Controls.OBC.CDL.Interfaces.RealInputPElePower demand
Buildings.Fluid.CHPs.BaseClasses.Interfaces.ModeTypeOutputopeModType of operating mode

Components

TypeNameDefaultDescription
Modelica.StateGraph.StepstaByStandby step
Modelica.StateGraph.SteppumOnPump on step
Modelica.StateGraph.StepWithSignalwarUpWarm-up step
Modelica.StateGraph.StepWithSignalcooDowCool-down step

Revisions

  • April 8, 2020, by Antoine Gautier:
    Refactored implementation.
  • December 03, 2019, by Jianjun Hu:
    Refactored implementation.
  • June 18, 2019, by Tea Zakula:
    First implementation.