modelWSEControl
Control unit for WSE
Information
This component decides if the WSE is set to on or off. The WSE is enabled when
- The WSE has been disabled for at least 20 minutes, and
- TWSE_CHWST > 0.9 TWetBul + TTowApp + TWSEApp
The WSE is disabled when
- The WSE has been enabled for at least 20 minutes, and
- TWSE_CHWRT < 1 + TWSE_CWST
where TWSE_CHWST is the chilled water supply temperature for the WSE, TWetBul is the wet bulb temperature, TTowApp is the cooling tower approach, TWSEApp is the approach for the WSE, TWSE_CHWRT is the chilled water return temperature for the WSE, and TWSE_CWST is the condenser water return temperature for the WSE.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.TemperatureDifference | dTOff | 1 | Temperature difference to switch WSE off |
| Modelica.Units.SI.TemperatureDifference | dTW | 1 | Temperature difference that is added to WSE on guard |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Interfaces.RealInput | wseCHWST | WSE chilled water supply temperature (water entering WSE) | |
| Modelica.Blocks.Interfaces.RealOutput | y2 | Control signal for chiller shutoff valve | |
| Modelica.Blocks.Interfaces.RealInput | TWetBul | Wet bulb temperature | |
| Modelica.Blocks.Interfaces.RealInput | towTApp | Cooling tower approach | |
| Modelica.Blocks.Interfaces.RealInput | wseCWST | WSE condenser water supply temperature (water entering WSE) | |
| Modelica.Blocks.Interfaces.RealOutput | y1 | Control signal for WSE shutoff valve |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Math.BooleanToReal | booToRea2 | ||
| Modelica.StateGraph.InitialStepWithSignal | off | ||
| Modelica.StateGraph.Transition | T1 | ||
| Modelica.StateGraph.Step | on | ||
| Modelica.StateGraph.Transition | T2 | ||
| Modelica.Blocks.Math.BooleanToReal | booToRea1 | ||
| Modelica.StateGraph.StateGraphRoot | stateGraphRoot | Root of the state graph |
Revisions
-
April 6, 2016, by Michael Wetter:
ReplacedModelica_StateGraph2withModelica.StateGraph. This is for issue 504. -
April 1, 2013, by Wangda Zuo:
Addedfinalattribute to initial state declaration. This is required for a successful model check in Dymola 2014 using the pedantic check. -
September 12, 2011, by Wangda Zuo:
Deleted the first order continuous block and changed the model to use SI units. -
July 20, 2011, by Wangda Zuo:
Added comments, redefined variables names, and merged to library. -
January 18, 2011, by Wangda Zuo:
First implementation.