Buildings.Electrical.AC.OnePhase.Lines

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Buildings.Electrical.AC.OnePhase.Lines

Package with models for AC electrical lines

Information

This package contains models for transmission lines and electrical networks.

Extends from Modelica.Icons.Package (Icon for standard packages).

Package Content

Name	Description
Line	Model of an electrical line
Network	Single phase AC network
TwoPortInductance	Model of an inductive element with two electrical ports
TwoPortRL	Model of a resistive-inductive element with two electrical ports
TwoPortRLC	Model of an RLC element with two electrical ports
TwoPortResistance	Model of a resistance with two electrical ports
Examples	Package with example models

Buildings.Electrical.AC.OnePhase.Lines.Line

Model of an electrical line

Buildings.Electrical.AC.OnePhase.Lines.Line

Information

This model represents an AC single phase cable. The model is based on Buildings.Electrical.AC.OnePhase.Lines.TwoPortRLC and provides functionalities to parametrize the values of R, L and C, either using commercial cables or using default values.

Extends from Buildings.Electrical.Transmission.BaseClasses.PartialLine (Partial cable line dispersion model).

Parameters

Type	Name	Default	Description
replaceable package PhaseSystem_p		PartialPhaseSystem	Phase system of terminal p
replaceable package PhaseSystem_n		PartialPhaseSystem	Phase system of terminal n
Length	l		Length of the line [m]
Power	P_nominal		Nominal power of the line [W]
Model
Assumptions
Boolean	use_C	false	Set to true to add a capacitance in the center of the line
Load	modelMode	Buildings.Electrical.Types.L...	Select between steady state and dynamic model
Thermal
Boolean	use_T	false	If true, enables the input for the temperature of the cable
Temperature	TCable	T_ref	Fixed temperature of the cable [K]
Tech. specification
Auto/Manual mode
CableMode	mode	Buildings.Electrical.Types.C...	Select if choosing the cable automatically or between a list of commercial options
Manual mode
Generic	commercialCable	Buildings.Electrical.Transmi...	Commercial cables options

Connectors

Type	Name	Description
replaceable package PhaseSystem_p		Phase system of terminal p
replaceable package PhaseSystem_n		Phase system of terminal n
input RealInput	T	Temperature of the cable

Modelica definition

model Line "Model of an electrical line" extends Buildings.Electrical.Transmission.BaseClasses.PartialLine( V_nominal(start = 110), redeclare package PhaseSystem_p = PhaseSystems.OnePhase, redeclare package PhaseSystem_n = PhaseSystems.OnePhase, redeclare Interfaces.Terminal_n terminal_n, redeclare Interfaces.Terminal_p terminal_p, commercialCable = Buildings.Electrical.Transmission.Functions.selectCable_low(P_nominal, V_nominal)); protected replaceable TwoPortRL line(R=R/3,L=L/3) constrainedby Buildings.Electrical.Transmission.BaseClasses.PartialTwoPortRLC( useHeatPort=true, mode=modelMode, M=M, T_ref=T_ref) "Model of the line"; equation connect(cableTemp.port, line.heatPort); connect(line.terminal_n, terminal_n); connect(terminal_p, line.terminal_p); end Line;

Buildings.Electrical.AC.OnePhase.Lines.Network

Single phase AC network

Buildings.Electrical.AC.OnePhase.Lines.Network

Information

This model represents a generalized electrical AC single phase network.

See Buildings.Electrical.Transmission.BaseClasses.PartialNetwork for information about the network model.

See Buildings.Electrical.Transmission.Grids.PartialGrid for more information about the topology of the network, such as the number of nodes, how they are connected, and the length of each connection.

Extends from Buildings.Electrical.Transmission.BaseClasses.PartialNetwork (Partial model that represent an electric network).

Parameters

Type	Name	Default	Description
Model
Assumptions
Boolean	use_C	false	If true, model the cable capacity
Load	modelMode	Types.Load.FixedZ_steady_state	Select between steady state and dynamic model

Modelica definition

model Network "Single phase AC network" extends Buildings.Electrical.Transmission.BaseClasses.PartialNetwork( V_nominal(start = 110), redeclare Interfaces.Terminal_p terminal, redeclare replaceable Transmission.Grids.TestGrid2Nodes grid, redeclare Line lines( commercialCable=grid.cables, each use_C=use_C, each modelMode=modelMode)); parameter Boolean use_C = false "If true, model the cable capacity"; parameter Buildings.Electrical.Types.Load modelMode=Types.Load.FixedZ_steady_state "Select between steady state and dynamic model"; Modelica.SIunits.Voltage VAbs[grid.nNodes] "RMS voltage of the grid nodes"; equation for i in 1:grid.nLinks loop connect(lines[i].terminal_p, terminal[grid.fromTo[i,1]]); connect(lines[i].terminal_n, terminal[grid.fromTo[i,2]]); end for; for i in 1:grid.nNodes loop VAbs[i] = Buildings.Electrical.PhaseSystems.OnePhase.systemVoltage(terminal[i].v); end for; end Network;

Buildings.Electrical.AC.OnePhase.Lines.TwoPortInductance

Model of an inductive element with two electrical ports

Buildings.Electrical.AC.OnePhase.Lines.TwoPortInductance

Information

This model represents an inductance that connects two AC one phase interfaces. This model can be used to represent a single phase cable in a AC grid.

The model represents the lumped inductance as shown in the figure below.

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

Parameters

Type	Name	Default	Description
replaceable package PhaseSystem_p		PartialPhaseSystem	Phase system of terminal p
replaceable package PhaseSystem_n		PartialPhaseSystem	Phase system of terminal n
Inductance	L		Inductance [H]
Modeling assumption
Load	mode	Buildings.Electrical.Types.L...	Type of model (e.g., steady state, dynamic, prescribed power consumption, etc.)

Connectors

Type	Name	Description
replaceable package PhaseSystem_p		Phase system of terminal p
replaceable package PhaseSystem_n		Phase system of terminal n

Modelica definition

model TwoPortInductance "Model of an inductive element with two electrical ports" extends Buildings.Electrical.Transmission.BaseClasses.PartialTwoPortInductance ( redeclare package PhaseSystem_p = PhaseSystems.OnePhase, redeclare package PhaseSystem_n = PhaseSystems.OnePhase, redeclare Interfaces.Terminal_n terminal_n, redeclare Interfaces.Terminal_p terminal_p); parameter Buildings.Electrical.Types.Load mode( min=Buildings.Electrical.Types.Load.FixedZ_steady_state, max=Buildings.Electrical.Types.Load.VariableZ_y_input)= Buildings.Electrical.Types.Load.FixedZ_steady_state "Type of model (e.g., steady state, dynamic, prescribed power consumption, etc.)"; protected Modelica.SIunits.AngularVelocity omega "Frequency of the quasi-stationary sine waves"; equation omega = der(PhaseSystem_p.thetaRef(terminal_p.theta)); if mode==Buildings.Electrical.Types.Load.FixedZ_dynamic then // Dynamics of the system der(L*terminal_p.i) + L*omega*PhaseSystem_p.j(terminal_p.i) = terminal_p.v - terminal_n.v; else // Steady state relationship L*omega*PhaseSystem_p.j(terminal_p.i) = terminal_p.v - terminal_n.v; end if; end TwoPortInductance;

Buildings.Electrical.AC.OnePhase.Lines.TwoPortRL

Model of a resistive-inductive element with two electrical ports

Buildings.Electrical.AC.OnePhase.Lines.TwoPortRL

Information

This model represents a resistance and an inductance connected in series with two AC one phase interfaces. This model can be used to represent a single phase cable in a AC grid.

The model represents the lumped RL cable as shown in the figure below.

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

Parameters

Type	Name	Default	Description
replaceable package PhaseSystem_p		PartialPhaseSystem	Phase system of terminal p
replaceable package PhaseSystem_n		PartialPhaseSystem	Phase system of terminal n
Boolean	useHeatPort	false	=true, if HeatPort is enabled
Temperature	T	T_ref	Fixed device temperature if useHeatPort = false [K]
Resistance	R		Resistance at temperature T_ref [Ohm]
Temperature	T_ref	298.15	Reference temperature [K]
Temperature	M	507.65	Temperature constant (R_actual = R*(M + T_heatPort)/(M + T_ref)) [K]
Capacitance	C	0	Capacity [F]
Inductance	L		Inductance [H]
Current	i_start[PhaseSystem_p.n]	zeros(PhaseSystem_p.n)	Initial current phasor of the line (positive if entering from terminal p) [A]
Nominal conditions
Voltage	V_nominal	0	Nominal voltage (V_nominal >= 0) [V]
Modeling assumption
Load	mode	Buildings.Electrical.Types.L...	Type of model (e.g., steady state, dynamic, prescribed power consumption, etc.)

Connectors

Type	Name	Description
replaceable package PhaseSystem_p		Phase system of terminal p
replaceable package PhaseSystem_n		Phase system of terminal n
HeatPort_a	heatPort

Modelica definition

model TwoPortRL "Model of a resistive-inductive element with two electrical ports" extends Buildings.Electrical.Transmission.BaseClasses.PartialTwoPortRLC( final V_nominal=0, redeclare package PhaseSystem_p = PhaseSystems.OnePhase, redeclare package PhaseSystem_n = PhaseSystems.OnePhase, redeclare Interfaces.Terminal_n terminal_n, redeclare Interfaces.Terminal_p terminal_p, final C=0); parameter Modelica.SIunits.Current i_start[PhaseSystem_p.n] = zeros(PhaseSystem_p.n) "Initial current phasor of the line (positive if entering from terminal p)"; parameter Buildings.Electrical.Types.Load mode( min=Buildings.Electrical.Types.Load.FixedZ_steady_state, max=Buildings.Electrical.Types.Load.FixedZ_dynamic)= Buildings.Electrical.Types.Load.FixedZ_steady_state "Type of model (e.g., steady state, dynamic, prescribed power consumption, etc.)"; protected Modelica.SIunits.Current i_p[2](start = i_start, each stateSelect=StateSelect.prefer) "Current phasor at terminal p"; Modelica.SIunits.AngularVelocity omega "Frequency of the quasi-stationary sine waves"; initial equation if mode==Buildings.Electrical.Types.Load.FixedZ_dynamic then i_p = i_start; end if; equation omega = der(PhaseSystem_p.thetaRef(terminal_p.theta)); terminal_p.i = - terminal_n.i; i_p = terminal_p.i; if mode==Buildings.Electrical.Types.Load.FixedZ_dynamic then // Dynamics of the system der(L*i_p) + L*omega*PhaseSystem_p.j(i_p) + i_p*diagonal(ones(PhaseSystem_p.n)*R_actual) = terminal_p.v - terminal_n.v; else // steady state relationship L*omega*PhaseSystem_p.j(i_p) + i_p*diagonal(ones(PhaseSystem_p.n)*R_actual) = terminal_p.v - terminal_n.v; end if; // Joule losses LossPower = R_actual*(i_p[1]^2 + i_p[2]^2); end TwoPortRL;

Buildings.Electrical.AC.OnePhase.Lines.TwoPortRLC

Model of an RLC element with two electrical ports

Buildings.Electrical.AC.OnePhase.Lines.TwoPortRLC

Information

This model represents a series of two resistive-inductive impedances and a capacitance that connects two AC single phase interfaces. This model can be used to represent a cable in a AC grid.

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

As can be seen in the figure, the resistance R and the inductance L are split in two halves and the capacitance is located in the center. The capacitance in the center is optional. If it is not present, set the parameter C=0. The model is either dynamic or static depending on the presence of the capacitive effect.

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

Parameters

Type	Name	Default	Description
replaceable package PhaseSystem_p		PartialPhaseSystem	Phase system of terminal p
replaceable package PhaseSystem_n		PartialPhaseSystem	Phase system of terminal n
Boolean	useHeatPort	false	=true, if HeatPort is enabled
Temperature	T	T_ref	Fixed device temperature if useHeatPort = false [K]
Resistance	R		Resistance at temperature T_ref [Ohm]
Temperature	T_ref	298.15	Reference temperature [K]
Temperature	M	507.65	Temperature constant (R_actual = R*(M + T_heatPort)/(M + T_ref)) [K]
Capacitance	C		Capacity [F]
Inductance	L		Inductance [H]
Voltage	Vc_start[2]	{V_nominal,0}	Initial voltage phasor of the capacitance located in the middle of the line [V]
Modeling assumption
Load	mode	Buildings.Electrical.Types.L...	Type of model (e.g., steady state, dynamic, prescribed power consumption, etc.)

Connectors

Type	Name	Description
replaceable package PhaseSystem_p		Phase system of terminal p
replaceable package PhaseSystem_n		Phase system of terminal n
HeatPort_a	heatPort

Modelica definition

model TwoPortRLC "Model of an RLC element with two electrical ports" extends Buildings.Electrical.Transmission.BaseClasses.PartialTwoPortRLC( V_nominal(start = 110), redeclare package PhaseSystem_p = PhaseSystems.OnePhase, redeclare package PhaseSystem_n = PhaseSystems.OnePhase, redeclare Interfaces.Terminal_n terminal_n( redeclare package PhaseSystem = PhaseSystem_n), redeclare Interfaces.Terminal_p terminal_p( redeclare package PhaseSystem = PhaseSystem_p)); parameter Modelica.SIunits.Voltage Vc_start[2] = {V_nominal,0} "Initial voltage phasor of the capacitance located in the middle of the line"; parameter Buildings.Electrical.Types.Load mode( min=Buildings.Electrical.Types.Load.FixedZ_steady_state, max=Buildings.Electrical.Types.Load.FixedZ_dynamic)= Buildings.Electrical.Types.Load.FixedZ_steady_state "Type of model (e.g., steady state, dynamic, prescribed power consumption, etc.)"; protected Modelica.SIunits.Voltage Vc[2](start = Vc_start, each stateSelect=StateSelect.prefer) "Voltage of the Capacitance located in the middle of the line"; Modelica.SIunits.Current Ic[2] "Currenbt of the capacitance located in the middle of the line"; Modelica.SIunits.AngularVelocity omega "Frequency of the quasi-stationary sine waves"; initial equation if C > 0 and mode == Buildings.Electrical.Types.Load.FixedZ_dynamic then Vc = Vc_start; end if; equation omega = der(PhaseSystem_p.thetaRef(terminal_p.theta)); terminal_p.i + terminal_n.i = Ic; L/2*omega*Buildings.Electrical.PhaseSystems.OnePhase.j(terminal_p.i) + terminal_p.i*diagonal(ones(PhaseSystem_p.n)*R_actual/2) = terminal_p.v - Vc; L/2*omega*Buildings.Electrical.PhaseSystems.OnePhase.j(terminal_n.i) + terminal_n.i*diagonal(ones(PhaseSystem_n.n)*R_actual/2) = terminal_n.v - Vc; if C > 0 then if mode == Buildings.Electrical.Types.Load.FixedZ_dynamic then // Dynamics of the system C*der(Vc) + omega*C*Buildings.Electrical.PhaseSystems.OnePhase.j(Vc) = Ic; else // steady state relationship omega*C*Buildings.Electrical.PhaseSystems.OnePhase.j(Vc) = Ic; end if; else // No capacitive effect, the voltage in the middle of the line is the linear // interpolation of the two phasors Vc = (terminal_p.v + terminal_n.v)/2; end if; // Joule losses LossPower = R_actual/2*(terminal_p.i[1]^2 + terminal_p.i[2]^2) + R_actual/2*(terminal_n.i[1]^2 + terminal_n.i[2]^2); end TwoPortRLC;

Buildings.Electrical.AC.OnePhase.Lines.TwoPortResistance

Model of a resistance with two electrical ports

Buildings.Electrical.AC.OnePhase.Lines.TwoPortResistance

Information

This model represents a resistance that connects two AC one phase interfaces. This model can be used to represent a single phase cable in a AC grid.

The model represents the lumped resistance as shown in the figure below.

Extends from Buildings.Electrical.Transmission.BaseClasses.PartialTwoPortResistance (Partial model of a resistive element that links two electrical connectors).

Parameters

Type	Name	Default	Description
replaceable package PhaseSystem_p		PartialPhaseSystem	Phase system of terminal p
replaceable package PhaseSystem_n		PartialPhaseSystem	Phase system of terminal n
Boolean	useHeatPort	false	=true, if HeatPort is enabled
Temperature	T	T_ref	Fixed device temperature if useHeatPort = false [K]
Resistance	R		Resistance at temperature T_ref [Ohm]
Temperature	T_ref	298.15	Reference temperature [K]
Temperature	M	507.65	Temperature constant (R_actual = R*(M + T_heatPort)/(M + T_ref)) [K]

Connectors

Type	Name	Description
replaceable package PhaseSystem_p		Phase system of terminal p
replaceable package PhaseSystem_n		Phase system of terminal n
HeatPort_a	heatPort

Modelica definition

model TwoPortResistance "Model of a resistance with two electrical ports" extends Buildings.Electrical.Transmission.BaseClasses.PartialTwoPortResistance ( redeclare package PhaseSystem_p = PhaseSystems.OnePhase, redeclare package PhaseSystem_n = PhaseSystems.OnePhase, redeclare Interfaces.Terminal_n terminal_n, redeclare Interfaces.Terminal_p terminal_p); equation terminal_p.v - terminal_n.v = terminal_p.i*diagonal(ones(PhaseSystem_p.n)*R_actual); // Joule losses LossPower = R_actual*(terminal_p.i[1]^2 + terminal_p.i[2]^2); end TwoPortResistance;

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