Help (1 Viewer)

[tegannyssa]

Can any one explain Eddy currents in a simple way. accually the whole last part of this topic thankxx

 

[alcalder]

Can any one explain Eddy currents in a simple way. accually the whole last part of this topic thankxx

OK, Eddy currents. Think of it this way. If you move a wire in a magnetic field, it induces a current in it.

An eddy current is just that sort of thing BUT it is not in a wire but in a larger piece of metal and so the current has to circulate around inside the metal.

So, inside a transformer, the magnetic field is changing. A changing magnetic field wants to induce a current. The current it wants to induce is at right angles to the changing magnetic field. Therefore, a current will be induced inside the iron core inside the transformer to try and oppose the change that caused it (Lenz's Law). If the iron core is one huge chunk of metal then it gets up a nice round eddy current that produces a nice big magnetic field that opposes the transformer and the tranformer is very inefficient.

Now, take that iron core and split it lengthwise and insulate the split bits from each other. The eddy currents can only flow around inside a smaller slice of metal. The effects of all the eddy currents cancel each other out, in some respects, and so the transformer is more effecient.

Does that help at all?

BTW Cool user name. Does it have Dr Who references, or is that just coincidence?