Buildings.Controls.OBC.UsersGuide
User's Guide
Information
The package Buildings.Controls.OBC contains the Control Description Language (CDL) and models for building control that are implemented using CDL. Both have been developed in the OpenBuildingControl project, see obc.lbl.gov.
The package contains control sequences for
- HVAC airside system control Buildings.Controls.OBC.ASHRAE.G36,
- radiant heating and cooling systems Buildings.Controls.OBC.RadiantSystems,
- outdoor lighting control Buildings.Controls.OBC.OutdoorLights, and
- shading device control Buildings.Controls.OBC.Shade.
The control sequences are composed of the elementary blocks from the package Buildings.Controls.OBC.CDL.
The package also contains models for unit conversions, Buildings.Controls.OBC.UnitConversions, and utilities models, such as Buildings.Controls.OBC.Utilities.OptimalStart, which output the optimal start time for an HVAC system.
The Control Description Language (CDL) can be found in Buildings.Controls.OBC.CDL and its specification is at obc.lbl.gov.
Extends from Modelica.Icons.Information (Icon for general information packages).
Package Content
| Name | Description |
|---|---|
 Conventions
|
Naming conventions in OBC package |
Buildings.Controls.OBC.UsersGuide.Conventions
Naming conventions in OBC package
Information
The Buildings.Controls.OBC package follows the naming conventions of
the Buildings Library,
see Buildings.UsersGuide.Conventions.
The table below shows some examples of commonly used names.
Note that the names are generally composed as follows:
-
If needed to understand the context, a prefix
ufor input oryfor output may be used. -
Next, the quantity is used, such as
TOutorTZonHea. -
Finally, as a postfix a qualifier may be added, such as
Setfor set point,Minfor minimum, orCoofor cooling.
Generally, we strive for short names, and therefore often prefix or postfix are omitted if
the type of the variable is clear from the context.
For example, a room temperature thermostat may simply use T as an input
as it is clear that this will be the room temperature.
| Instance names | |
| Name | Comments |
|---|---|
TOut (hOut) |
Outdoor air temperature (enthalpy) |
TZonHeaSet (TZonCooSet) |
Zone heating (cooling) set point temperature |
VDis_flow |
Measured discharge airflow rate |
dpBui |
Building static pressure difference, relative to ambient |
uOpeMod |
Zone group operating mode |
uResReq |
Number of reset requests |
uSupFan |
Current supply fan enabling status, true: fan is enabled |
uSupFanSpe |
Current supply fan speed |
uDam |
Measured damper position |
uHea (uCoo) |
Heating (cooling) loop signal |
yPosMin (yPosMax) |
Minimum (maximum) position |
yHeaCoi (yCooCoi) |
Heating (cooling) coil control signal |
uChiIsoVal |
Chiller condenser water isolation valve status |
dpChiWat_remote |
Chilled water differntial statis pressure from remote sensor |
TChiWatRet |
Chilled water return temperature |
VChiWat_flow |
Measured chilled water volume flow rate |
uHeaPreCon |
Chiller head pressure control loop signal from chiller controller |
yChiPumSpe |
Chilled water pump speed setpoint |
yChi |
Chiller status setpoint |
yMinValPos |
Minimum valve position setpoint |
| Parameter names | |
| Name | Comments |
use_TMix |
Set to true if mixed air temperature measurement is used |
have_occSen (have_winSen) |
Set to true if the zone has occupancy (window) sensor |
AFlo |
Area of the zone |
VDisHeaSetMax_flow (VDisCooSetMax_flow) |
Zone maximum heating (cooling) airflow set point |
VOutPerAre_flow (VOutPerPer_flow) |
Outdoor airflow rate per unit area (person) |
V_flow_nominal |
Nominal volume flow rate |
VOutMin_flow |
Calculated minimum outdoor airflow rate at design stage |
pMinSet (pMaxSet) |
Minimum (maximum) pressure set point for fan speed control |
TSupSetMin (TSupSetMax) |
Lowest (Highest) cooling supply air temperature |
TOccHeaSet (TUnoHeaSet) |
Zone occupied (unoccupied) heating set point |
TZonCooMax (TZonCooMin) |
Maximum (minimum) zone cooling set point when cooling is on |
retDamPhyPosMax (outDamPhyPosMax) |
Physically fixed maximum position of the return (outdoor) air damper |
samplePeriod |
Sample period |
zonDisEffHea (zonDisEffCoo) |
Zone air distribution effectiveness during heating (cooling) |
kCoo |
Gain for cooling control loop signal |
TiCoo |
Time constant of integrator block for cooling control loop signal |
TdCoo |
Time constant of derivative block for cooling control loop signal |
nChi |
Total number of chillers |
have_parChi |
True: the plant has parallel chillers |
have_heaChiWatPum |
True: the plant has headed chilled water pumps |
have_fixSpeConWatPum |
True: the plant has fixed speed condenser water pumps |
need_reduceChillerDemand |
True: the plant needs to limit chiller demand when chiller staging |
minChiLif |
Minimum allowable lift at minimum load for chiller |
TChiWatSupMin |
Minimum chilled water supply temperature |
dpChiWatPumMin |
Minimum chilled water pump differential static pressure |
lift_min |
Chiller minimum lift |
Extends from Modelica.Icons.Information (Icon for general information packages).