Eddy current (also called Foucault current) was discovered by French physicist Leon Foucault in 185 1 year. It is caused by the intersection of moving magnetic field and metal conductor, or the vertical intersection of moving metal conductor and magnetic field. In short, it is caused by electromagnetic induction effect. This action produces an electric current in the conductor.

When the current in one coil changes with time, induced current will be generated in another nearby coil due to electromagnetic induction. In fact, any conductor near this coil will produce induced current.

The current generated by electromagnetic induction in a conductor. Also known as Foucault current. When the conductor moves in a non-uniform magnetic field, or when the conductor is stationary but has a time-varying magnetic field, or when both situations occur at the same time, it will cause the relative cutting of the magnetic field lines and the conductor.

According to the law of electromagnetic induction, induced electromotive force is generated in the conductor, thus driving the current. The distribution of current in a conductor varies with the surface shape of the conductor and the distribution of magnetic field, and its path is often like a vortex in water, so it is called eddy current.