Proportional Setpoint Control
Does anyone have any methods for more accurately Is it possible to define proportional control for supply air flow and temperature in EnergyPlus? I want to set up a proportional control similar to what can be done in IES-VE.
For example (assume a conventional VAV reheat system):
- Heating setpoint is 19C, cooling setpoint is 24C.
- Between these values, neither heating or cooling should be active, because this is the deadband, and airflow should be at a minimum ventilation.
- As space temperature rises above 24C, ramp up the supply air flow rate proportionally between 24 and 26 (assuming there is a 2K proportional bandwidth), and the same with heating down from 19 to 17.
From what I can tell, there is not a good method for setting up the this control sequences sequence for the thermostat setpoints in EnergyPlus, ideally without having to get into EMS code? code. It seems that the standard controllers like ThermostatSetpoint:DualSetpoint
with a ZoneControl:Thermostat
operate somewhat ideally. I tried using the ZoneControl:Thermostat:StagedDualSetpoint
with just one stage because it offers a throttling range, but the results were inconsistent and don't give an option to use proportional instead of on/off.
I'd really like to be able to properly and explicitly whatever is being used. The VAV objects do allow to set up a proporational control like you can in IES. For example, when the room is between 19 and 22, do nothing, then ramp up the cooling proportionally between 22 and 24 (or specify a setpoint min and max flow rates for heating and cooling, but I don't understand how those are used.
Here's a sketch of 23 +/- 1deg), and the same with heating between 17 and 19. Dual Maximum control is code required in CA so I check to see what CBECC-Com was doing, but it doesn't look right to me.I'm trying to do, if that helps to clarify it. I assume this is fairly standard, though I know some terms change around the world.