Dev:Commercial

Dev:Commercial - Commercial building developer's guide

Note

The small office building is part of the original implementation of the commercial module and is expected to be deprecated when the full commercial building implementation is completed. This will include deprecation of the multizone class. Small office buildings will be derived from the building implementation when that is validated and released.

Building

The building class implements that abstract class used to solve all linearized multizone building models. All multizone commercial building classes are derived from this class.

Class members

General properties
Property	Unit	Constraints	Default	Description	Remarks
T	degF	N×1 ∈ R	Ø	Node temperatures
N	(int16)	∈ N+	1	Number of nodes in model
U	Btu/degF/h	N×N symmetric ∈ R*2	Ø	Node conductances
C	Btu/degF	N×1 ∈ R*	Ø	Node capacitance	NaN indicates outdoor node
Q	Btu/h	N×1 ∈ R	Ø	Node heat flows
Qs	Btu/h	N×1 ∈ R*	Ø	Node solar heat gain
Qi	Btu/h	N×1 ∈ R*	Ø	Node internal heat gain
Default HVAC properties
Property	Unit	Constraints	Default	Description	Remarks
Qfl	Btu/h	N×1 ∈ R*	NaN	Node fan heat gain at low power
Qfh	Btu/h	N×1 ∈ R*	NaN	Node fan heat gain at high power
Qf	Btu/h	N×1 ∈ R*	NaN	Node heat gain from fans
Qhc	Btu/h	N×1 ∈ R*	NaN	Node heating capacity
Qh	Btu/h	N×1 ∈ R*	NaN	Node heat gain from heating
Qcc	Btu/h	N×1 ∈ R*	NaN	Node cooling capacity
Qc	Btu/h	N×1 ∈ R*	NaN	Node heat loss from cooling
Note : NaN is used to indicate that no default HVAC equipment is associated with the node
Default controller properties
Property	Unit	Constraints	Default	Description	Remarks
Ts	(double)	N×1 ∈ {0,1,2,3,4,5}	NaN	HVAC state	0=OFF, 1=VENT, 2=HEAT, 3=COOL, 4=AUX, 5=ECON
Vm	pu/h	N×1 ∈ R*	NaN	Minimum ventilation required
Th	degF	N×1 ∈ R+	NaN	Heating set-point	Must be less than <math>Tc-2Td</math>
Tc	degF	N×1 ∈ R+	NaN	Cooling set-point	Must be greater than <math>Th+2Td</math>
Td	degF	N×1 ∈ R+	NaN	Set-point deadband
tl	s	N×1 ∈ N+	300	Control lockout time	Must be less than or equal to maximum_timestep
Note : NaN is used to indicate that no default control equipment is associated with the node
Other members
autosize	(bool)	∈ {TRUE,FALSE}	FALSE	Enables automatic sizing of arrays
load	(enduse)			Electric end use load composition

Default HVAC Controller

The default controller implements a simple single zone vent/heat/cool/aux control. To override the default controller you must implement the plc() function is the derived class.

The default control strategy for node n is as follows:

if mode == OFF || mode == VENT
  if T < Th-2*Td
    mode = AUX
  else if T < Th - Td/2
    mode = HEAT
  else if T > Tc + Td/2
    mode = COOL
  else if Vm > 0 
    mode = VENT
  else
    mode = OFF

else if mode == HEAT
  if T < Th-2*Td
    mode = AUX
  else if T > Th+Td/2
    if Vm > 0
      mode = VENT
    else
      mode = OFF

else if mode == COOL
  if T < Tc - Td/2
    if Vm > 0
      mode = VENT
    else
      mode = OFF

else if mode == AUX
  if T > Th - Td/2
    if Vm > 0
      mode = VENT
    else
      mode = OFF

Note

Implementing the plc() function for a building means that the default controller is disabled for all nodes in the building. This means that if you want to continue using the default controller for some nodes you must call the building::plc() function directly for that node.

See also

• User's manuals
  • Commercial module
  • Building types
    • Office
    • Large office  TODO: 
    • Small office  TODO: 
    • Retail  TODO: 
    • Grocery  TODO: 
    • Food_service  TODO: 
    • Lodging  TODO: 
    • School  TODO: 
    • Health  TODO: 
• Technical documents
  • Requirements
  • Specifications
  • Technical support document
  • Developer's guide
  • Validation
• Residential
• Modules