How do the I2R losses in a rotary converter compare to a DC generator of identical dimensions___________?
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Answer: B. less
Explanation
Inside a rotary converter armature, the alternating current and direct current flow in opposite directions relative to each other. This opposing current flow causes a partial cancellation of the net current passing through the copper conductors. Consequently, the resulting copper I squared R resistive losses are drastically lower than those in a standard DC generator. Armature winding losses are caused by the flow of electric current through the finite electrical resistance of the copper wire. A rotary converter combines AC and DC paths within the exact same set of physical armature windings on a single rotor core. Higher current density normally generates more heat, but internal current cancellation mitigates this thermal effect in rotary converters.
A standard DC generator experiences unidirectional current throughout its armature, leading to higher baseline I squared R resistive losses. Options C and D suggest higher losses, which contradicts the principle of internal current opposition that actually reduces thermal dissipation. Saying the losses are the same ignores the beneficial cancellation effect produced by simultaneously handling AC and DC in one winding.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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