10. A three-phase transformer consists of a bank of single-phase transformers connected to form a Dd0 connection. A fault on one of the transformers causes it to be removed from the circuit, and the remaining two transformers are connected in an open-delta (V-V) connection. Show that the capacity of the open-delta connected transformers is 58% of the delta-connected transformers.

10. A three-phase transformer consists of a bank of single-phase transformers connected to form a Dd0 connection. A fault on one of the transformers causes it to be removed from the circuit, and the remaining two transformers are connected in an open-delta (V-V) connection. Show that the capacity of the open-delta connected transformers is 58% of the delta-connected transformers.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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A short transmission line connects a step-up transformer on the source side with a series impedance of j0.5 ohms (referred to the primary) to a step-down transformer on the load side with a series impedance of 50 ohms (referred to the primary). The turn ratio of the step-up transformer is 1:10 and a no-load primary voltage of 13.2 (line-to-line) kv. The step-down transformer has a turn ratio of 15:1 and it has a Y-connected, balanced load of 0.667 +j 0.111 ohms connected to its secondary side. A capacitor bank of -j0.239 ohms is added parallel to the load. Assuming an ideal transmission line, the effective impedance of the system (per phase) seen by the source would be: O A. 0.093 + j0.249 O B. 0.372 + j0.996 OC.3.72 + j9.96 O D. None of the other choices are correct O E. 0.186 + j0.498
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