How to calculate transformer iron core losses?

The alternating magnetic flux that flows through the transformerâ€™s magnetic core causes iron loss.

To calculate **transformer** iron core losses, first determine the losses caused by

- Hysteresis and
- Eddy currents

in the core material.

These losses depend on the core material parameters,

- The frequency of the magnetic flux, and
- The maximum flux density.

Hereâ€™s a step-by-step calculation for calculating these losses.

## Hysteresis Loss

The hysteresis loss (P_{h}) in a transformer core is calculated as:

## P_{h} = k_{h} B_{max} ^{n} f V

Where

The hysteresis constant (k_{h}) depends on core material.

B_{max} represents maximal flux density in core (in Tesla).

The Steinmetz exponent ranges between 1.6 & 2.5 for the majority of core materials.

f represents the frequency of the magnetic flow (Hz).

V represents the volume of core (mÂł).

## Eddy Current Loss

The equation for eddy current loss (P_{e}) in a transformer core is as follows:

## P_{e} = k_{h} B_{max} ^{2} f ^{2} t ^{2} V

Where

The eddy current constant (k_{e}) is determined by the core materialâ€™s electrical resistivity.

t represents the thickness of core laminations (in meters).

B_{max} represents maximal flux density in core (in Tesla).

f represents the frequency of magnetic flow (Hz).

V represents the volume of the core (mÂł).

## Total Core (Iron) Loss

The total core loss (P core) combines hysteresis & eddy current losses: