Block that outputs the supply temperature control loop signal, and the coil valve postions for VAV system with multiple zones, implemented according to the ASHRAE Guideline G36, PART 5.N.2 (Supply air temperature control).
The supply air temperature control loop signal uTSup
is computed using a PI controller that tracks the supply air temperature
setpoint TSupSet
.
If the fan is off, then uTSup = 0
.
Heating valve control signal (or modulating electric heating
coil if applicable) yHea
and cooling valve control signal yCoo
are sequenced based on the supply air temperature control loop signal uTSup
.
From uTSup = uHeaMax
to uTSup = -1
,
yHea
increases linearly from 0 to 1.
Similarly, uTSup = uCooMin
to uTSup = +1
,
yCoo
increases linearly from 0 to 1.
The output uTSup
can be used in a controller for the economizer.