The three phase rating of a three winding transformer are: Primary: Y connected 6.6kV, 15.000KVA Secondary: Y connected 33kV, 10,000KVA Tertiary: A connected 2.2kV, 7.500KVA With resistance neglected the following leakage impedances are calculated from the short circuit test: Measured from the primary side: ZPS = j2.472 ZPT = j2.90N Measured from the secondary side: ZST = j8.70N Find the p.u impedance of the star connected equivalent circuit on a base of 6.6kV, 15,000KVA in the primary side. %3D

The three phase rating of a three winding transformer are: Primary: Y connected 6.6kV, 15.000KVA Secondary: Y connected 33kV, 10,000KVA Tertiary: A connected 2.2kV, 7.500KVA With resistance neglected the following leakage impedances are calculated from the short circuit test: Measured from the primary side: ZPS = j2.472 ZPT = j2.90N Measured from the secondary side: ZST = j8.70N Find the p.u impedance of the star connected equivalent circuit on a base of 6.6kV, 15,000KVA in the primary side. %3D

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 3.62P: Rework Example 3.12 for a+10 tap, providing a 10 increase for the high-voltage winding.

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