1. In a 3-phase overhead system, each line is suspended by a string of 3 insulators. The voltage across the top unit (i.e. near the tower) and middle unit are 10 kV and 11 kV respectively. Calculate () the ratio of shunt capacitance to self capacitance of each insulator, (ii) the string efficiency and (iii) line voltage. [(1) 0-1 (ii) 86-76% (iii) 59 kV]

1. In a 3-phase overhead system, each line is suspended by a string of 3 insulators. The voltage across the top unit (i.e. near the tower) and middle unit are 10 kV and 11 kV respectively. Calculate () the ratio of shunt capacitance to self capacitance of each insulator, (ii) the string efficiency and (iii) line voltage. [(1) 0-1 (ii) 86-76% (iii) 59 kV]

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 3.25P: Consider a single-phase electric system shown in Figure 3.33. Transformers are rated as follows:...

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