blockFanSpeed
Information
Block that outputs the fan enable signal and the fan speed signal based on the heating and cooling loop signals. The implemented sequence is based on ASHRAE Guideline 36, 2021, Part 5.22.4.
The fan enable signal y1Fan is set to false
when the operating mode signal opeMod is unoccupied,
and is set to true otherwise.
The fan speed signal yFan is varied from
the minimum cooling mode fan speed cooSpe_min to the maximum
cooling mode fan speed cooSpe_max,
when the cooling loop signal uCoo varies from the minimum limit
uCoo_min to the maximum limit uCoo_max.
Similarly, yFan is varied from the minimum heating mode fan speed
heaSpe_min to the maximum heating mode fan speed heaSpe_max,
when the heating loop signal uHea varies from the minimum limit
uHea_min to the maximum limit uHea_max.
The setpoint in deadband mode is equal to the deadband fan speed deaSpe.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | have_cooCoi | True if the unit has a cooling coil | |
| Boolean | have_heaCoi | True if the unit has a heating coil | |
| Deadband | |||
| Real | deaSpe | 0.1 | Deadband mode fan speed |
| Real | heaDea | 0.1 | Heating loop signal limit above which fan operation changes from deadband mode to heating mode |
| Real | cooDea | 0.1 | Cooling loop signal limit above which fan operation changes from deadband mode to cooling mode |
| Heating loop | |||
| Real | heaSpe_min | 0.1 | Minimum heating mode fan speed |
| Real | uHea_min | 0.5 | Minimum heating loop signal at which fan speed is modified |
| Real | heaSpe_max | 0.6 | Maximum heating mode fan speed |
| Real | uHea_max | 1 | Maximum heating loop signal at which fan speed is modified |
| Cooling loop | |||
| Real | cooSpe_min | 0.2 | Minimum cooling mode fan speed |
| Real | uCoo_min | 0.5 | Minimum cooling loop signal at which fan speed is modified |
| Real | cooSpe_max | 1 | Maximum cooling mode fan speed |
| Real | uCoo_max | 1 | Maximum cooling loop signal at which fan speed is modified |
| Advanced | |||
| Real | deaHysLim | 0.05 | Hysteresis limits for deadband mode transitions |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Interfaces.BooleanInput | u1FanPro | Fan proven on signal | |
| Buildings.Controls.OBC.CDL.Interfaces.IntegerInput | opeMod | System operating mode | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | uHea | Heating loop signal | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | uCoo | Cooling loop signal | |
| Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput | y1Fan | Fan command on status | |
| Buildings.Controls.OBC.CDL.Interfaces.RealOutput | yFan | Fan command speed |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Integers.Equal | isUnOcc | Check if zone is unoccupied | |
| Buildings.Controls.OBC.CDL.Logical.Not | notUno | Enable only if zone is not in unoccupied mode | |
| Buildings.Controls.OBC.CDL.Reals.Switch | swiFanPro | Switch fan speed to deadband speed until the fan is proven ON | |
| Buildings.Controls.OBC.CDL.Conversions.BooleanToReal | booToRea | Convert fan enable signal to Real | |
| Buildings.Controls.OBC.CDL.Reals.Line | linHeaFanSpe | Heating fan speed signal | |
| Buildings.Controls.OBC.CDL.Reals.Line | linCooFanSpe | Cooling fan speed signal | |
| Buildings.Controls.OBC.CDL.Reals.Hysteresis | hysDeaHea | Hysteresis for switching between deadband mode and heating mode | |
| Buildings.Controls.OBC.CDL.Reals.Switch | swiDeaHea | Switch for turning on heating mode from deadband mode | |
| Buildings.Controls.OBC.CDL.Reals.Hysteresis | hysDeaCoo | Hysteresis for switching on cooling mode from deadband mode | |
| Buildings.Controls.OBC.CDL.Reals.Switch | swiDeaCoo | Switch for turning on cooling mode from deadband mode | |
| Buildings.Controls.OBC.CDL.Reals.Multiply | mulFanSpe | Multiply fan speed signal by fan enable signal | |
| Buildings.Controls.OBC.CDL.Reals.Multiply | mulDeaSpe | Multiply deadband speed signal by fan enable signal | |
| Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter | gai | Dummy gain | |
| Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter | gai1 | Dummy gain |
Revisions
-
March 17, 2022, by Karthik Devaprasad:
First implementation.