Typical values for remanence, coercivity and the temperature coefficient of remanence are provided for the common permanent magnetic materials illustrated below.
Linear demagnetization curves are modelled. The characteristic, temperature-dependent "knee" of many permanent magnetic materials is not considered, since proper design of permanent magnetic circuits should avoid operation of permanent magnets "below" that point due to partial demagnetization. As a result, the temperature coefficient of coercivity is not considered. Only the temperature coefficient of remanence alpha_Br is accounted for, since it describes the dependende of the demagnetization curve on the temperature sufficiently for the region "above the knee-point".
Additional user-specific materials can be defined as needed.
Name | Description |
---|---|
![]() | Relative permeability and temperature-dependent coercivity of permanent magnetic materials |
![]() | NdFeB sintered; exemplary values |
![]() | Sm2Co17 sintered, exemplary values |
![]() | SmCo5 sintered, exemplary values |
![]() | Plastic-bonded NdFeB, exemplary values |
![]() | Plastic-bonded Sm-Co, exemplary values |
![]() | Hard ferrite sintered, exemplary values |
![]() | Plastic-bonded hard ferrite, exemplary values |
![]() | Record for permanent magnetic material data |
Please refer to the description of the enclosing package HardMagnetic for a description of all elements of this package.
In the records defining the characteristics of a permanent magnetic materials, remanence B_rRef and coercivity H_cBRef are given for a reference temperature T_refCelsius, usually 20°C. Using the also defined temperature coefficient of remanence alpha_Br, remanence B_r and coercivity H_cB are calculated for a given operating temperature of the permanent magnet T_opCelsius. In addition, the relative permeability my_r is calculated. Have a look at Examples.ElectrodynamicActuator.MagneticCircuitModel for an exemplary use of this component.
Type | Name | Default | Description |
---|---|---|---|
CelsiusTemperature | T_opCelsius | 20 | Operating temperature [degC] |
model PermanentMagnetBehaviour "Relative permeability and temperature-dependent coercivity of permanent magnetic materials" replaceable record material = Modelica_Magnetic.Material.HardMagnetic.PermanentMagnetData "Characteristics of common permanent magnetic materials"; material mat; parameter SI.CelsiusTemperature T_opCelsius = 20 "Operating temperature"; final parameter SI.MagneticFluxDensity B_r = mat.B_rRef * (1 + mat.alpha_Br *(T_opCelsius - mat.T_refCelsius)) "Remanence at operating temperature"; final parameter SI.MagneticFieldStrength H_cB = mat.H_cBRef * (1 + mat.alpha_Br *(T_opCelsius - mat.T_refCelsius)) "Coercivity at operating temperature"; final parameter SI.RelativePermeability my_r = B_r/ (my_0 * H_cB) "Relative permeability"; end PermanentMagnetBehaviour;
Please refer to the description of the enclosing package HardMagnetic for a description of all permanent magnetic material characteristics of this package.
Type | Name | Default | Description |
---|---|---|---|
MagneticFieldStrength | H_cBRef | 900000 | Coercivity at reference temperature [A/m] |
MagneticFluxDensity | B_rRef | 1.2 | Remanence at reference temperature [T] |
CelsiusTemperature | T_refCelsius | 20 | Reference temperature [degC] |
TemperatureCoefficient | alpha_Br | -0.001 | Temperature coefficient of remanence [1/K] |
record NdFeB = Modelica_Magnetic.Material.HardMagnetic.PermanentMagnetData ( H_cBRef=900000, B_rRef=1.2, T_refCelsius=20, alpha_Br=-0.001) "NdFeB sintered; exemplary values";
Please refer to the description of the enclosing package HardMagnetic for a description of all permanent magnetic material characteristics of this package.
Type | Name | Default | Description |
---|---|---|---|
MagneticFieldStrength | H_cBRef | 750000 | Coercivity at reference temperature [A/m] |
MagneticFluxDensity | B_rRef | 1.02 | Remanence at reference temperature [T] |
CelsiusTemperature | T_refCelsius | 20 | Reference temperature [degC] |
TemperatureCoefficient | alpha_Br | -0.0003 | Temperature coefficient of remanence [1/K] |
record Sm2Co17 = Modelica_Magnetic.Material.HardMagnetic.PermanentMagnetData ( H_cBRef=750000, B_rRef=1.02, T_refCelsius=20, alpha_Br=-0.0003) "Sm2Co17 sintered, exemplary values";
Please refer to the description of the enclosing package HardMagnetic for a description of all permanent magnetic material characteristics of this package.
Type | Name | Default | Description |
---|---|---|---|
MagneticFieldStrength | H_cBRef | 720000 | Coercivity at reference temperature [A/m] |
MagneticFluxDensity | B_rRef | 0.95 | Remanence at reference temperature [T] |
CelsiusTemperature | T_refCelsius | 20 | Reference temperature [degC] |
TemperatureCoefficient | alpha_Br | -0.0004 | Temperature coefficient of remanence [1/K] |
record SmCo5 = Modelica_Magnetic.Material.HardMagnetic.PermanentMagnetData ( H_cBRef=720000, B_rRef=0.95, T_refCelsius=20, alpha_Br=-0.0004) "SmCo5 sintered, exemplary values";
Please refer to the description of the enclosing package HardMagnetic for a description of all permanent magnetic material characteristics of this package.
Type | Name | Default | Description |
---|---|---|---|
MagneticFieldStrength | H_cBRef | 400000 | Coercivity at reference temperature [A/m] |
MagneticFluxDensity | B_rRef | 0.6 | Remanence at reference temperature [T] |
CelsiusTemperature | T_refCelsius | 20 | Reference temperature [degC] |
TemperatureCoefficient | alpha_Br | -0.001 | Temperature coefficient of remanence [1/K] |
record PlasticNdFeB = Modelica_Magnetic.Material.HardMagnetic.PermanentMagnetData ( H_cBRef=400000, B_rRef=0.6, T_refCelsius=20, alpha_Br=-0.001) "Plastic-bonded NdFeB, exemplary values";
Please refer to the description of the enclosing package HardMagnetic for a description of all permanent magnetic material characteristics of this package.
Type | Name | Default | Description |
---|---|---|---|
MagneticFieldStrength | H_cBRef | 385000 | Coercivity at reference temperature [A/m] |
MagneticFluxDensity | B_rRef | 0.57 | Remanence at reference temperature [T] |
CelsiusTemperature | T_refCelsius | 20 | Reference temperature [degC] |
TemperatureCoefficient | alpha_Br | -0.0004 | Temperature coefficient of remanence [1/K] |
record PlasticSmCo = Modelica_Magnetic.Material.HardMagnetic.PermanentMagnetData ( H_cBRef=385000, B_rRef=0.57, T_refCelsius=20, alpha_Br=-0.0004) "Plastic-bonded Sm-Co, exemplary values";
Please refer to the description of the enclosing package HardMagnetic for a description of all permanent magnetic material characteristics of this package.
Type | Name | Default | Description |
---|---|---|---|
MagneticFieldStrength | H_cBRef | 170000 | Coercivity at reference temperature [A/m] |
MagneticFluxDensity | B_rRef | 0.38 | Remanence at reference temperature [T] |
CelsiusTemperature | T_refCelsius | 20 | Reference temperature [degC] |
TemperatureCoefficient | alpha_Br | -0.002 | Temperature coefficient of remanence [1/K] |
record HardFerrite = Modelica_Magnetic.Material.HardMagnetic.PermanentMagnetData ( H_cBRef=170000, B_rRef=0.38, T_refCelsius=20, alpha_Br=-0.002) "Hard ferrite sintered, exemplary values";
Please refer to the description of the enclosing package HardMagnetic for a description of all permanent magnetic material characteristics of this package.
Type | Name | Default | Description |
---|---|---|---|
MagneticFieldStrength | H_cBRef | 130000 | Coercivity at reference temperature [A/m] |
MagneticFluxDensity | B_rRef | 0.21 | Remanence at reference temperature [T] |
CelsiusTemperature | T_refCelsius | 20 | Reference temperature [degC] |
TemperatureCoefficient | alpha_Br | -0.002 | Temperature coefficient of remanence [1/K] |
record PlasticHardFerrite = Modelica_Magnetic.Material.HardMagnetic.PermanentMagnetData ( H_cBRef=130000, B_rRef=0.21, T_refCelsius=20, alpha_Br=-0.002) "Plastic-bonded hard ferrite, exemplary values";
Please refer to the description of the enclosing package HardMagnetic for a description of all permanent magnetic material characteristics of this package.
Type | Name | Default | Description |
---|---|---|---|
MagneticFieldStrength | H_cBRef | 1 | Coercivity at reference temperature [A/m] |
MagneticFluxDensity | B_rRef | 1 | Remanence at reference temperature [T] |
CelsiusTemperature | T_refCelsius | 20 | Reference temperature [degC] |
TemperatureCoefficient | alpha_Br | 0 | Temperature coefficient of remanence [1/K] |
record PermanentMagnetData "Record for permanent magnetic material data" extends Modelica.Icons.Record; parameter SI.MagneticFieldStrength H_cBRef = 1 "Coercivity at reference temperature"; parameter SI.MagneticFluxDensity B_rRef = 1 "Remanence at reference temperature"; parameter SI.CelsiusTemperature T_refCelsius = 20 "Reference temperature"; parameter Utilities.TemperatureCoefficient alpha_Br = 0 "Temperature coefficient of remanence"; end PermanentMagnetData;
Type | Name | Default | Description |
---|---|---|---|
MagneticFieldStrength | H_cBRef | 1 | Coercivity at reference temperature [A/m] |
MagneticFluxDensity | B_rRef | 1 | Remanence at reference temperature [T] |
CelsiusTemperature | T_refCelsius | 20 | Reference temperature [degC] |
TemperatureCoefficient | alpha_Br | 0 | Temperature coefficient of remanence [1/K] |
replaceable record material = Modelica_Magnetic.Material.HardMagnetic.PermanentMagnetData "Characteristics of common permanent magnetic materials";