Material database for power electronic usage

The materialdatabase mainly contains complex magnetic and dielectric data of soft-magnetic ferrite materials under sinusoidal excitation. Typical target applications of the provided material data are magnetic components in power electronic converters operated at switching frequencies reaching from 100 kHz to 3 MHz. The database allows to compare materials and measurement setups, to work with fit functions (e.g., Steinmetz), and features data export as interpolation grids. FEM solvers like Comsol can directly import these interpolation grids and incorporate the data in frequency-domain simulations. The amplitude-dependency of the complex permeability is then typically modeled via local linearization (e.g., based on Newton iterations). The open-source FEM Magnetics Toolbox (FEMMT) automatically allows to import material data from this database.

Overview

• Measurement data is stored in a .csv-files for each combination of material and measurement setup.

• Data sources:

  • Complex Permeability:

    • Datasheet:

      Data based on datasheet or manufacturer design tool data (e.g., TDK MDT ). The complex permeability is computed from the given loss density and amplitude permeability.

    • MagNet:

      Data from the MagNet project. The time series data of the sinusoidal measurements is simplified to complex permeability assuming perfectly elliptical hysteresis. For the MagNet data, also DC bias is provided.

    • LEA MTB (LEA Material Test Bench):

      Data from measurements at the department of Power Electronics and Electrical Drives at Paderborn University. The measurements are taken with a setup employing the capacitive compensated two-winding method.

  • Complex Permittivity:

    • LEA MTB (LEA Material Test Bench):

      Measurements at the department of Power Electronics and Electrical Drives at Paderborn University. The dielectric measurements are taken with a Wayne Kerr 6515B impedance analyzer on thin silver-plated cuboidal cores.

• The database currently contains the ferrite materials listed in the following table:

Installation

pip install materialdatabase

Example Data

The data is stored in .csv files:

Example Code

Material properties can be loaded as follows:

mdb_data = mdb.Data()
material_name = mdb.Material.N95
permeability = mdb_data.get_complex_permeability(material=material_name,
data_source=mdb.DataSource.LEA_MTB,
pv_fit_function=mdb.FitFunction.enhancedSteinmetz)
print(f"Exemplary complex permeability data: \n {permeability.measurement_data.head()} \n")
permittivity = mdb_data.get_complex_permittivity(material=material_name,
data_source=mdb.DataSource.LEA_MTB)
print(f"Exemplary complex permittivity data: \n {permittivity.measurement_data.head()} \n ")

Output:

Exemplary complex permeability data:
probe f T b mu_real mu_imag h_offset
0 R29.5x19x14.9 59629.0 30.145 0.040125 3955.516035 333.486173 0
1 R29.5x19x14.9 58929.0 30.154 0.049834 4050.789996 380.241871 0
2 R29.5x19x14.9 58329.0 30.154 0.058502 4138.476021 424.009115 0
3 R29.5x19x14.9 57929.0 30.147 0.066572 4239.539939 458.079275 0
4 R29.5x19x14.9 57529.0 30.158 0.074332 4303.405675 488.755116 0
Exemplary complex permittivity data:
probe f T eps_real eps_imag
0 LE2 107760.0 28 95567.710843 36977.344836
1 LE2 121546.0 28 93791.671181 35002.540113
2 LE2 137096.0 28 92085.767038 33189.049457
3 LE2 154635.0 28 90442.389511 31563.885192
4 LE2 174418.0 28 88863.933437 30088.808585

Detailed examples with material comparisons and data exporting can be found in the "examples" folder.

Usage via FEM Magnetics Toolbox (FEMMT)

FEMMT can be installed using the python pip package manager.

pip install femmt

For working with the latest version, refer to the documentation

Bug Reports

Please use the issues report button within github to report bugs.

Changelog

Find the changelog here.