Package with example models
Information
This package contains examples for the use of models that can be found in
Buildings.Electrical.DC.Loads.
Extends from Modelica.Icons.ExamplesPackage (Icon for packages containing runnable examples).
Package Content
Example model to check the linearized load model
Information
This example demonstrates the use of a linealized load model Buildings.Electrical.DC.Loads.Conductor.
Both loads are connected to the same DC voltage source through a resistive element that represents a line. The loads consume the same amount of power that is specified by the input ramp signal.
The nonlinear conductor model NonlinearLoad
consumes exactly the amount of power specified by the input NonlinearLoad.Pow
.
The linearized conductor model LinearizedLoad
does not consumes the amount of power specified by the input LinearizedLoad.Pow
. The voltage at the load deviates from the nominal value when the power consumption increases. Since the model is approximated in a neighbor of the nominal voltage, moving from that point introduces approximation errors. The plot below shows the error introduced with such an approximation.
The linearized load is tested over a voltage variation of about 30 % of the nominal voltage and within this range
the maximum error is 1.23457 % that occurs when the voltage deviation is 11.11 %.
Extends from Modelica.Icons.Example (Icon for runnable examples).
Modelica definition
model LinearizedLoad
"Example model to check the linearized load model"
extends Modelica.Icons.Example;
Real error = (sen_nlin.P - sen_lin.P)*100/sen_nlin.P
"Percentage of error between the linearized and actual power consumption";
Real deltaV = LinearLoad.V_nominal - sen_lin.V
"Voltage distance between nominal condition and actual voltage";
Buildings.Electrical.DC.Loads.Conductor NonlinearLoad(
linearized=false,
mode=Buildings.Electrical.Types.Load.VariableZ_P_input,
V_nominal=100,
P_nominal=0)
"Nonlinear load model";
Sources.ConstantVoltage sou(V=100)
"Voltage source";
Modelica.Electrical.Analog.Basic.Ground gro
"Ground";
Lines.TwoPortResistance Rline1(R=2)
"Line resistance";
Sensors.GeneralizedSensor sen_nlin
"Sensor";
Buildings.Electrical.DC.Loads.Conductor LinearLoad(
mode=Buildings.Electrical.Types.Load.VariableZ_P_input,
V_nominal=100,
linearized=true,
P_nominal=0)
"Linearized load model";
Sensors.GeneralizedSensor sen_lin
"Sensor";
Lines.TwoPortResistance Rline2(R=2)
"Line resistance";
Modelica.Blocks.Sources.Ramp ramp(
duration=0.5,
startTime=0.2,
offset=-50,
height=-950)
"Power consumption";
equation
connect(sou.terminal, Rline1.terminal_n);
connect(Rline1.terminal_p, sen_nlin.terminal_n);
connect(sen_nlin.terminal_p, NonlinearLoad.terminal);
connect(LinearLoad.terminal, sen_lin.terminal_p);
connect(sou.n, gro.p);
connect(sou.terminal, Rline2.terminal_n);
connect(Rline2.terminal_p, sen_lin.terminal_n);
connect(LinearLoad.Pow, ramp.y);
connect(NonlinearLoad.Pow, ramp.y);
end LinearizedLoad;
Example model for resistor
Information
This example demonstrates the use of the resistor model.
Extends from Modelica.Icons.Example (Icon for runnable examples).
Modelica definition
Example using variable loads models
Information
This example shows how to use three different types of load models.
Each load is of type
Buildings.Electrical.DC.Loads.Conductor.
The first load loa1
consumes a constant amount of power.
The second and the third loads (loa2
and loa3
) consume a variable amount of power.
The load loa2
has a variable input y
between 0 and 1 that specifies the portion of
nominal power that is consumed.
The load loa3
has a variable input Pow
that represents the actual power consumed
(or produced) by the load.
Extends from Modelica.Icons.Example (Icon for runnable examples).
Modelica definition
model VariableLoad
"Example using variable loads models"
extends Modelica.Icons.Example;
Conductor loa1(
V_nominal=12,
linearized=false,
P_nominal=-50)
"Load";
Sources.ConstantVoltage sou(V=12)
"Voltage source";
Modelica.Electrical.Analog.Basic.Ground gro
"Ground";
Conductor loa2( mode=Types.Load.VariableZ_y_input,
V_nominal=12,
P_nominal=-50)
"Load";
Modelica.Blocks.Sources.Ramp varLoad_y(
height=0.8,
duration=0.5,
startTime=0.3,
offset=0)
"Power signal";
Conductor loa3(
V_nominal=12,
P_nominal=0,
mode=Buildings.Electrical.Types.Load.VariableZ_P_input)
"Load";
Modelica.Blocks.Sources.Ramp varLoad_P(
duration=0.5,
startTime=0.3,
height=120,
offset=-20)
"Power signal";
Lines.TwoPortResistance res(R=0.1)
"Line resistance";
Sensors.GeneralizedSensor sen
"Sensor";
equation
connect(sou.terminal, loa2.terminal);
connect(varLoad_y.y, loa2.y);
connect(sou.terminal, loa3.terminal);
connect(varLoad_P.y, loa3.Pow);
connect(sou.terminal, res.terminal_n);
connect(res.terminal_p, sen.terminal_n);
connect(sen.terminal_p, loa1.terminal);
connect(sou.n, gro.p);
end VariableLoad;
Automatically generated Mon Jul 13 14:23:37 2015.