modelTwoPortRCLine

Model of a two port DC resistance and capacity (T-model)

Extends from Buildings.Electrical.Transmission.BaseClasses.PartialTwoPortRLC (Partial model of an RLC element that links two electrical connectors).

Information

This model represents a series of two resistances and a capacitance that connect two DC interfaces. This model can be used to represent a cable in a DC grid.

The model represents the lumped resistances and capacity (T-model) as shown in the figure below.

image

As can be seen in the figure, the resistance R is split in two halves and the capacitance is located in the center. The capacitance in the center is optional and can be selected using the boolean flag use_C = true. The model is either dynamic or static depending on the presence of the capacitive effect.

Parameters

TypeNameDefaultDescription
BooleanuseHeatPort (from ConditionalHeatPort)false= true, if heatPort is enabled
SI.TemperatureT (from ConditionalHeatPort)293.15Fixed device temperature if useHeatPort = false
Modelica.Units.SI.ResistanceR (from PartialTwoPortRLC)Resistance at temperature T_ref
Modelica.Units.SI.TemperatureT_ref (from PartialTwoPortRLC)298.15Reference temperature
Modelica.Units.SI.TemperatureM (from PartialTwoPortRLC)507.65Temperature constant (R_actual = R*(M + T_heatPort)/(M + T_ref))
Modelica.Units.SI.CapacitanceC (from PartialTwoPortRLC)Capacity
Modelica.Units.SI.InductanceL (from PartialTwoPortRLC)Inductance
Modelica.Units.SI.VoltageVc_startV_nominalInitial value of the voltage of the capacitance in the middle of the line
Nominal conditions
Modelica.Units.SI.VoltageV_nominal (from PartialTwoPortRLC)Nominal voltage (V_nominal >= 0)
Model › Assumptions
Booleanuse_CfalseSet to true to add a capacitance in the center of the line

Connectors

TypeNameDefaultDescription
Buildings.Electrical.Interfaces.BaseTerminalterminal_n (from PartialBaseTwoPort)Electric terminal side p
Buildings.Electrical.Interfaces.BaseTerminalterminal_p (from PartialBaseTwoPort)Electric terminal side n
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_aheatPort (from ConditionalHeatPort)Conditional heat port

Components

TypeNameDefaultDescription
SI.PowerLossPower (from ConditionalHeatPort)Loss power leaving component via heatPort
SI.TemperatureT_heatPort (from ConditionalHeatPort)Temperature of heatPort
Modelica.Units.SI.ResistanceR_actual (from PartialTwoPortRLC)Actual resistance = R*(M + T_heatPort)/(M + T_ref)
Modelica.Units.SI.VoltageVcVoltage of the capacitor

Revisions

  • March 19, 2015, by Michael Wetter:
    Removed redeclaration of phase system in Terminal_n and Terminal_p as it is already declared to the be the same phase system, and it is not declared to be replaceable. This avoids a translation error in OpenModelica.
  • March 10, 2015, by Marco Bonvini:
    Added initial equation and parameter Vc_start.
  • January 14, 2015, by Marco Bonvini:
    Added equation that represents Joule losses
  • June 2, 2014, by Marco Bonvini:
    Revised documentation.
  • October 31, 2013, by Marco Bonvini:
    First implementation.