Why is the armature of a DC generator laminated_______________?
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Answer: D. reduce eddy current loss
Explanation
Solid iron cores would allow large circulating eddy currents to flow freely. Laminating the core with insulated sheets breaks up these continuous electrical paths. Breaking up the paths successfully reduces destructive eddy current power losses. Eddy currents generate unwanted heat and reduce electrical machine efficiency. Insulation varnish coats each thin steel lamina used to build armature cores. Core losses consist of both eddy current and hysteresis power components.
Generator manufacturers use high-grade silicon steel laminations to improve efficiency. Minimizing core losses prevents excessive operating temperatures in continuous-duty machines. Proper lamination design is standard practice in all AC and DC rotating equipment. Reducing bulk would weaken the mechanical structure of the heavy rotating armature. Providing bulk is achieved through solid shafts rather than core lamination. Insulating the core specifically stops eddy current paths rather than core functions.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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