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Byju's Answer

Standard XII

Physics

Phasor

Consider the ...

Question

Consider the following statements for the fully transposed transmission line.
Statement (I) : Positive and negative sequence impedance are equal.
Statement (II) : Zero sequence impedance is much smaller than the positive or negative sequence impedance.

Both statements are true

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Statement I is true, Statement II is false

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Statement I is false, Statement II is true

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Both statements are false

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Solution

The correct option is B Statement I is true, Statement II is false
For the fully transposed transmission line,
Positive sequence impedance $Z_{1} = Z_{s} - Z_{m}$
Negative sequence impedance $Z_{2} = Z_{s} - Z_{m}$
Zero sequence impedance $Z_{0} = Z_{s} + 2 Z_{m} + 3 Z_{n}$
Where, $Z_{s} =$ Self impedance / ph
$Z_{m} =$ Mutual impedance / ph

If the system voltages are unbalanced, we have a neutral current $I_{n}$ flowing through the neutral (ground) having impedance $Z_{n}$

From above equations, we can say

Positive and negative sequence impedance are equal.

Zero sequence impedance is much larger than the positive or negative sequence impedance.

$∴$ Statement (I) is true and statement (II) is false.

Suggest Corrections

Similar questions

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Consider the following statements for the fully transposed transmission line. Statement (I) : Positive and negative sequence impedance are equal. Statement (II) : Zero sequence impedance is much smaller than the positive or negative sequence impedance.

Consider the following statements for the fully transposed transmission line.
Statement (I) : Positive and negative sequence impedance are equal.
Statement (II) : Zero sequence impedance is much smaller than the positive or negative sequence impedance.