Concept explainers
The value of the CT secondary current (I’) and VT secondary voltage (V’).

Answer to Problem 10.1P
Explanation of Solution
Given Information:
Calculation:
The secondary voltage of the voltage transformer (V’) is,
Substitute the values in the above equation,
Now, the current (I) entering the primary of the current transformer is,
On substituting the values in the above equation,
And get,
Here, the CT equivalent circuit is,
Fig: CT equivalent circuit diagram
Now, the secondary current of CT is,
Substituting the values in the above equation,
From the above equivalent circuit diagram, the secondary current consists of two components, there are
Whereas, I’ is the relay current and Ie is the exciting current.
CT error is Zero in the given question.
So that the exciting current is Zero, (Ie=0), therefore,
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Chapter 10 Solutions
POWER SYS. ANALYSIS+DESIGN
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- Power System Analysis and Design (MindTap Course ...Electrical EngineeringISBN:9781305632134Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. SarmaPublisher:Cengage Learning
