(a) Partial breakdown and breakdown (b) Discharge and breakdown Numerical Problems 1. In a coaxial power cable the radius of the conductor is 25 mm and the thickness of insulation is 8 mm. Calculate the Schwaiger factor n in this field configuration. Comment on uniformity of electric field. 2. What will be the most economical (optimum) conductor diameter of a single core power cable to be used on 132 kV power systems? Also find the diameter over the insulation provided to the conductor if the maximum permissible stress is not to exceed 8 kV/mm. 3. Two parallel plates which are oppositely charged are placed 5 cm apart. The potential difference, in volts, between the plates is 100 kV. Find the electric field intensity between them. 4. In a 220 kV rated voltage coaxial spherical system of a GIS the radius of the inner HV electrode is 10.0 cm and the SF6 gas insula- tion thickness of 18.0 cm is provided around. Find 61 5. 6.

(a) Partial breakdown and breakdown (b) Discharge and breakdown Numerical Problems 1. In a coaxial power cable the radius of the conductor is 25 mm and the thickness of insulation is 8 mm. Calculate the Schwaiger factor n in this field configuration. Comment on uniformity of electric field. 2. What will be the most economical (optimum) conductor diameter of a single core power cable to be used on 132 kV power systems? Also find the diameter over the insulation provided to the conductor if the maximum permissible stress is not to exceed 8 kV/mm. 3. Two parallel plates which are oppositely charged are placed 5 cm apart. The potential difference, in volts, between the plates is 100 kV. Find the electric field intensity between them. 4. In a 220 kV rated voltage coaxial spherical system of a GIS the radius of the inner HV electrode is 10.0 cm and the SF6 gas insula- tion thickness of 18.0 cm is provided around. Find 61 5. 6.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.37P: Three single-phase two-winding transformers, each rated 25MVA,54.2/5.42kV, are connected to form a...

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