modelDelayedOnOffController
CHP On/Off controller
Information
Overview
This is model is the decision maker in the CHP model. According to different conditions and timings it decides if the CHP can be turned on or off.
Concept
The following control decisions are implemented:
- Switch On when the flow temperature is lower than a setpoint.
- Switch Off when the CHP should work in a range lower than its minimum allowable capacity.
- Allow the CHP to be switched On only if it was Off for more than a certain amount of time (delay) or it was On beforehand.
- Allow the CHP to be switched Off only if it was On for more than a certain amount of time (delay) or it was Off beforehand.
- Emergency measures such as maximum allowable flow and return temperatures are implemented.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Temperature | maxTReturn | Maximum return temperature | |
| Modelica.Units.SI.ThermodynamicTemperature | minDeltaT | Minimum flow and return temperature difference | |
| Modelica.Units.SI.ThermodynamicTemperature | TFlowRange | Range of the flow temperature | |
| Modelica.Units.SI.Time | delayTime | On/Off delay time | |
| Boolean | initialOutput | false | Initial output |
| Real | delayUnit | Delay unit | |
| Real | minCapacity | Minimum allowable working capacity in percent |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Interfaces.RealInput | flowTemp | Flow temperature | |
| Modelica.Blocks.Interfaces.RealInput | returnTemp | Return temperature | |
| Modelica.Blocks.Interfaces.BooleanOutput | y | Signal if controller is on or off | |
| Modelica.Blocks.Interfaces.RealInput | controllerOutput | Controller output | |
| Modelica.Blocks.Interfaces.RealInput | minCapacity_in | Minimal capacity | |
| Modelica.Blocks.Interfaces.BooleanInput | externalOn | False for shut down | |
| Modelica.Blocks.Interfaces.RealInput | flowTemp_setpoint | Flow temperature setpoint | |
| Modelica.Blocks.Logical.And | and1 | ||
| Modelica.Blocks.Logical.Pre | pre2 | ||
| Modelica.Blocks.Logical.OnOffController | onOffController | OnOff controller | |
| Modelica.Blocks.Logical.LessThreshold | lessThreshold | Maximum allowable flow temperature variation | |
| Modelica.Blocks.Logical.Or | or1 | ||
| Modelica.Blocks.Logical.GreaterThreshold | greaterThreshold | Max return temperature limit | |
| Modelica.Blocks.Discrete.UnitDelay | unitDelay | Last value | |
| Modelica.Blocks.Math.Feedback | feedback | ||
| Modelica.Blocks.Logical.Not | not1 | ||
| Modelica.Blocks.Logical.Not | not2 | ||
| Modelica.Blocks.Logical.LogicalSwitch | logicalSwitch | ||
| Modelica.Blocks.Logical.Not | not3 | ||
| Modelica.Blocks.Logical.Or | or3 | ||
| Modelica.Blocks.Logical.LessThreshold | lessThreshold1 | ||
| Modelica.Blocks.Logical.GreaterEqualThreshold | greaterEqualThreshold | Emergency measure | |
| Modelica.Blocks.Logical.Or | or4 | ||
| Modelica.Blocks.MathBoolean.OnDelay | onDelay | On delay | |
| Modelica.Blocks.MathBoolean.OnDelay | onDelay1 | On delay | |
| Modelica.Blocks.Nonlinear.FixedDelay | fixedDelay | Fixed delay |
Revisions
-
December 08, 2016 by Moritz Lauster:
Adapted to AixLib conventions -
October 11, 2016 by Pooyan Jahangiri:
Variable names updated and merged with AixLib -
January 23, 2014 by Pooyan Jahangiri:
Formatted documentation appropriately -
January 31, 2011 by Pooyan Jahangiri:
Implemented