QuickField

A new approach to field modelling

Main >> >> Coil with ferromagnetic core

Coil with ferromagnetic core

QuickField simulation example

Sinusoidal voltage is applied to the electric coil with ferromagnetic core.

Problem Type
Axisymmetric problem of AC magnetics.

Geometry
Coil with ferromagnetic core Sinusoidal voltage is applied to the electric coil with ferromagnetic core. Core Winding C R U 120 mm Ø 40 mm Ø 50 mm Ø 100 mm

Given
Number of turns w = 120
AC voltage value U = 13.33 V
Frequency f = 50 Hz.
Conductivity of the winding (copper) g = 56 MS/m;
Conductivity of the steel core g = 10 MS/m;
Magnetic permeability of the steel core μ - nonlinear:

Task
Determine the electric current within the coil winding.

Solution
Due to the model symmetry only half of the coil is presented in the model. Therefore the circuit elements' values are defined twice less than in the real object.
Current vs. time plot in the real coil has non-sinusoidal shape and requires transient magnetic analysis. With AC magnetics module we can estimate RMS value much faster. The drawback of this approach is that we cannot estimate true wave form.

Results

Problem Current wave form, A
Transient 50.5·sin(wt + 108°) + 5.9·sin(3wt - 41°) + 3.9·sin(5wt + 148°)
AC magnetics 49.9·sin(wt + 104°)

AC current waveform and transient current waveform, calculated in transient magnetics example.

Eddy currents distribution in the coil winding.
Eddy current in the coil winding