What is meant by capacitance grading in a cable__________?
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Answer: A. use of dielectrics of different permeabilities
Explanation
Capacitance grading in high-voltage cables involves using multiple dielectric layers with different relative permittivities Varying the permittivity across concentric insulation layers helps equalize the electrostatic stress throughout the thickness This technique prevents excessive electrical stress concentration near the inner conductor surface of thick cables Permittivity determines how much electric flux a material can hold per unit of applied electric field strength Ungraded cables experience maximum electrical stress right at the conductor surface which can cause premature insulation failure Graded dielectric construction places materials with higher permittivity closer to the high voltage center conductor
High voltage power transmission cables use capacitance grading to maximize insulation performance and reduce overall diameter Manufacturing underground cables requires precise control over dielectric layer permittivity values to ensure reliability Preventing localized dielectric breakdown extends the operational lifespan of critical subterranean power links Grading according to cable capacitance per kilometer length describes capacitance measurement metrics rather than dielectric grading Cables using single dielectric in different concentrations contradicts the multi-layer permittivity grading principle Countering inductance effects requires capacitive compensation networks rather than internal cable insulation grading
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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