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Question
Why and where are eddy currents are undesirable? How are they minimized?
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Solution
Undesirable effects of eddy currents:
The soft iron core is used in dynamo transformers, motors, generators, etc. When a.c is passed through these instruments the flux changes and eddy currents are set up in the core. Therefore, the core is heated up so the electrical energy is wasted in the form of heat energy.
Minimization of the undesirable effect of eddy current:
- To minimize the undesirable effect of eddy currents, laminated or insulated iron core is used which minimizes the magnitude of eddy currents.
- If the surface area of the metal plate is reduced, amount of eddy current generated is reduced.
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