Apr 26,2023
Transformer mutual inductance
Mutual inductance is a property of two coils that are placed near each other such that a change in current in one coil induces an electromotive force (EMF) in the other coil. The mutual inductance, M, is a measure of this coupling between the two coils and is defined as the ratio of the induced EMF in one coil to the rate of change of current in the other coil.
In the context of transformers, mutual inductance refers to the coupling between the primary and secondary coils of a transformer. When an alternating current flows through the primary coil, it creates a magnetic field that induces an EMF in the secondary coil. The mutual inductance of a transformer is determined by the number of turns in each coil, the size and shape of the coils, and the distance between them.
The formula for mutual inductance between two coils is given by:
M = N1N2Φ / I1
where N1 and N2 are the number of turns in the two coils, Φ is the magnetic flux linking the two coils, and I1 is the current in the first coil. The unit of mutual inductance is henry (H).
In a transformer, the mutual inductance determines the voltage ratio between the primary and secondary coils. If the number of turns in the secondary coil is greater than the number of turns in the primary coil, the voltage across the secondary coil will be greater than the voltage across the primary coil. This is because the mutual inductance is directly proportional to the number of turns in each coil.
