GATE EE 2018 Set 1 — Question 32
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Question
A bus admittance matrix for an electric power system has non-zero elements. The minimum number of branches (transmission lines and transformers) in this system are _____ (up to 2 decimal places).
Correct answer
3500 to 3500
Solution
In a bus admittance matrix () of size , the number of non-zero elements is given by , where is the number of buses and is the number of branches (assuming no shunt branches are explicitly counted as separate branches from the bus-to-ground connections).Given:
Number of non-zero elements = Using the formula:
Thus, the minimum number of branches is 3500.
Number of non-zero elements = Using the formula:
Thus, the minimum number of branches is 3500.
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