Field strength

Due to the magnetic field strength, there is an appropriate magnetic induction and respective polarizing effect.

Frequency Influence

The frequency that is the speed of the demagnetization strongly influences the shape of the hysteresis loop. The faster the demagnetization, the bigger is the curve. The reason for this is, among others, eddy currents. The frequency behaviour is influenced as well as the electrical resistance and the grain and sheet wall structure.

Marginal frequency

The marginal frequency is the frequency at which a magnetic material shows a sharp drop in permeability.

Hysteresis loop

The relationship between the flux density and the field strength is determined by the hysteresis loop. The form of hysteresis loop is dependent, among others, on the material and the frequency. Even with decreasing field strength, the induction does not go back on a new curve but on a curve is that lying higher. This ‘time lag’ is defined as the hysteresis loop.

Induction B (flux density)

The relationship between the flux density and the field strength is determined by the hysteresis loop. The form of hysteresis loop is dependent, among others, on the material and the frequency. Even with decreasing field strength, the induction does not go back on a new curve but on a curve is that lying higher. This ‘time lag’ is defined as the hysteresis loop. According to Maxwell's second equation, the change in the induction and the size of the encompassing winding induced voltage is proportional to each other.

B= µ0*H+J= µ0*(H+M)

B: Induction
J: Polarisation
M: Magnetisation
H: Field strength/Magnetising field
For soft magnetic materials, B corresponds to J.

Coupling

The transfer of electromagnetic radiation between interfering source and sink interference occurs via the coupling. In this way, for example, the energy of a electric circuit to another circuit can be transferred. The transfer can be conducted both as well as triggered by radiation. Basically, there are the four different types of coupling:

Galvanic, on common current paths
Inductive, on magnetic fields
Capacitive, on electric fields
Radiation, by remote electromagnetic far-field

Magnetisation M

The vectorial sum of the magnetic moments of atoms is in terms of unit volume.

New curve

The magnetising curve is the first magnetization of a magnetic material which is not yet magnetised. This is:

M=J/ µ0=B/ µ0-H
B: Induction
J: Polarisation
M: Magnetisation
H: Field strength/magnetising field
M is the dimension of the field strength (A/m).

Permeability µ

As permeability is the ratio between induction (B) and magnetising field (H), there is a distinction between different types of permeability:
Absolute permeability
Definition: µ=B/H
In empty spaces this is identical to the field constants µ0

Initial permeability
This is amplitude permeability in disappearing small field strength and induction. Usually, this is the value in very small field strength, but not the specified µ4 limit. Often, this means the µ4 and permeability is at a field strength of Ĥ=4mA/cm.

Maximum permeability
This is the largest permeability value on the new curve.

Relative permeability
The relative permeability is obtained by dividing the absolute permeability with the field constant µ0: µr= µ/µ0=(1/ µ0)*(B/H) Most of the relative permeability is used in practice.

Polarisation J

The context between Polarisation J, Magnetisierung M and Induktion B can be described as follows:

J=B-µ0*H
mit B=µ0*(H+M)
daraus folgt:
J=µ0*(H+M)- µ0*H= µ0*M
B: Induction
J: Polarisation
M: Magnetisation
H: Field strength/magnetising field

Saturation

A material is saturated, if all nuclear magnets are oriented parallel to the magnetic field. This means that the polarization can’t increase but the induction can. For soft magnetic materials to achieve saturation, only comparatively small field strengths are required. Saturation polarization Js and saturation induction Bs are almost identical.

Interference source/Sink fault

Components, equipment or facilities which emit electromagnetic fields affect the environment and are therefore considered interference sources. At the same time, used parts, equipment or facilities are the sources of electromagnetic fields. It is a sink fault if the function of the affected areas is received or changed. A single component can be simultaneously a source and sink, as electromagnetic fields are emitted simultaneously but the function of fields received by other components or equipment can be affected. On closer inspection, a disturbance source is the emission of particular importance in the sink fault, practically, the interference immunity.

The Haug Group: More than distribution.

As a medium-sized corporate group, the Haug Group stands for more than just electronics distribution. In addition to the distribution of electronic components, the Haug Group focuses on cable assembly, inductors and shielding solutions for low-frequency fields.

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