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[EnergyPlus_Support] Is it necessary to include a PID controller in VAV flow control model?
Hi,
I have question about VAV flow rate control.
In EnergyPlus, VAV system generally can give very good control on indoor air temperature if chiller and boilers' capacity is enough. Basically, the indoor air temperature results shown by EnergyPlus will very closely follow the setpoint. I think this is because EnergyPlus calculates the air flow rate by a equation Q=Cp*m*deltT, so EnergyPlus know exactly how much air should be supplied to a room to reach the setpoint.
However, in reality, it is known that VAV terminal damper uses PID controller to control the flow rate. Every PID controller will have a rising time, settling time, etc. This means, in reality, the indoor air temperature can never closely follow the setpoint temperature.
My question is that, in reality, how long it will take for VAV system to reach the setpoint? Is it necessary to use external program (e.g. Matlab) to model a PID controller and couple it with EnergyPlus? I raised this question because I am testing a control algorithm that will frequently change the indoor air temperature setpoint based different conditions. I am curious that, in reality, if we frequently change the room setpoint temperature (say, every 1 min), will the room respond that fast? I want to test it in EnergyPlus.
Best,
Zhiang Zhang
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Posted by: zhangzhizza@xxxxxxxxxxxx
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