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packaged rooftop heat pump model

asked 2019-01-26 12:11:58 -0500

LampLamprop gravatar image

updated 2019-01-27 09:42:59 -0500

Dear all,

I am trying to run a simulation which includes a model o packaged rooftop heat pump (air to air).

Is there any clue about what is the most appropriate that I can use in softwares energyplus or simulink or dymola?

kind regards

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answered 2019-01-29 13:21:32 -0500

LampLamprop gravatar image

Thank you for your answer.

I have already tried these objects but the problem is that I want to implement a co-simulation scheme in which I should be able to control my Heat Pump from matlab through bcvtb and give "from outside" the values of fan speed and inlet damper position (or even compressor speed) for the heat pump. From what I have seen, these capabilities are not given in energyplus objects of HP: it is necessary to define a certain thermostat and you cannot control the fan speed and inlet damper opening .

kind regards

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Oh, I see. I don't use co-simulation so am not familiar with which "capabilities are not given in energyplus objects of HP". Can you elaborate?

rraustad gravatar image rraustad  ( 2019-01-29 13:41:08 -0500 )edit

The capabilities that I would like the model to have is to give me the opportunity to define externally an speed and inlet damper position (or even compressor speed) according to a controller that is going to be implemented in matlab.

LampLamprop gravatar image LampLamprop  ( 2019-01-29 13:49:58 -0500 )edit

Yes, I get that. I just don't know what EnergyPlus needs to respond to the external signal. Can you tell me which objects in EnergyPlus do work with Matlab? Is it EnergyPlus' EMS commands?

rraustad gravatar image rraustad  ( 2019-01-29 14:08:38 -0500 )edit

The communication between the two softwares will be done via bcvtb which is a middleware. The objects of energyplus that make it feasible to insert signals from the outside are all the externalinterface objects.

LampLamprop gravatar image LampLamprop  ( 2019-01-29 14:18:10 -0500 )edit

The bcvtb manual shows that EMS is used to communicate between EnergyPlus and an outside controller. AirloopHVAC:UnitarySystem has an EMS actuator "Unitary HVAC, name, "Sensible Load Request" that could be used to modulate the air sytem.

rraustad gravatar image rraustad  ( 2019-01-29 14:43:17 -0500 )edit

answered 2019-01-29 12:24:00 -0500

updated 2019-01-29 14:59:30 -0500

In EnergyPlus you can use the AirloopHVAC equipment that model heat pumps (or ZoneHVAC if modeling a single zone). See:

AirLoopHVAC:UnitarySystem (can model any coil types) AirLoopHVAC:UnitaryHeatPump:AirToAir (only for HP's) AirLoopHVAC:UnitaryHeatPump:WaterToAir AirLoopHVAC:UnitaryHeatPump:AirToAir:MultiSpeed

Also see the \EnergyPlusVX-X-X\ExampleFiles folder for the ExampleFiles-ObjectsLink.html file to find which example files show use of these heat pump objects. And review the InputOutputReference documentation for each object (\Documentation folder).

I only see 3 methods for using ExternalInterface.

    \memo This object activates the external interface of EnergyPlus. If the object
    \memo ExternalInterface is present, then all ExtnernalInterface:* objects will receive
    \memo their values from the BCVTB interface or from FMUs at each zone time step.
    \memo If this object is not present, then the values of these objects will be fixed at the
    \memo value declared in the "initial value" field of the corresponding object, and a
    \memo warning will be written to the EnergyPlus error file.
A1;  \field Name of External Interface
    \note Name of External Interface
    \type choice
    \key PtolemyServer
    \key FunctionalMockupUnitImport
    \key FunctionalMockupUnitExport
    \note Currently, the only valid entries are PtolemyServer, FunctionalMockupUnitImport, and FunctionalMockupUnitExport.
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Asked: 2019-01-26 12:11:58 -0500

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Last updated: Jan 29 '19