1

GATE EE 2018

Numerical

+1

-0.33

The series impedance matrix of a short three-phase transmission line in phase coordinates is
$$\left[ {\matrix{
{{Z_s}} & {{Z_m}} & {{Z_m}} \cr
{{Z_m}} & {{Z_s}} & {{Z_m}} \cr
{{Z_m}} & {{Z_m}} & {{Z_s}} \cr
} } \right]$$.

If the positive sequence impedance is (1 + 𝑗 10) $$\Omega $$, and the zero sequence is (4 + 𝑗 31) $$\Omega $$, then the imaginary part of Z

If the positive sequence impedance is (1 + 𝑗 10) $$\Omega $$, and the zero sequence is (4 + 𝑗 31) $$\Omega $$, then the imaginary part of Z

_{m}(in $$\Omega $$) is ______(up to 2 decimal places).Your input ____

2

GATE EE 2018

Numerical

+1

-0.33

The positive, negative and zero sequence impedances of a 125 MVA, three-phase, 15.5 kV,
star-grounded, 50 Hz generator are 𝑗0.1 pu, j0.05 pu and j0.01 pu respectively on the
machine rating base. The machine is unloaded and working at the rated terminal voltage. If
the grounding impedance of the generator is j0.01 pu, then the magnitude of fault current
for a b-phase to ground fault (in kA) is __________ (up to 2 decimal places).

Your input ____

3

GATE EE 2014 Set 1

MCQ (Single Correct Answer)

+1

-0.3

Three phase to ground fault takes place at locations $${F_1}$$ and $${F_2}$$ in the system shown in the figure.

If the fault takes place at location $${F_1}$$, then the voltage and the current at bus A are $${V_F1}$$ and $${{\rm I}_{F1}}$$ respectively. If the fault takes place at location $${F_2}$$, then the voltage and the current at bus A are $${V_{F2}}$$ and $${{\rm I}_{F2}}$$ respectively.

The correct statement about voltages and currents during faults at $${F_1}$$ and $${F_2}$$ is

4

GATE EE 2014 Set 1

MCQ (Single Correct Answer)

+1

-0.3

A 2-bus system and corresponding zero sequence network are shown in the figure.

The transformers T_{1} and T_{2} are connected as

Questions Asked from Symmetrical Components and Symmetrical and Unsymmetrical Faults (Marks 1)

Number in Brackets after Paper Indicates No. of Questions

GATE EE Subjects

Electric Circuits

Electromagnetic Fields

Signals and Systems

Electrical Machines

Engineering Mathematics

General Aptitude

Power System Analysis

Electrical and Electronics Measurement

Analog Electronics

Control Systems

Power Electronics