Power System Analysis, Stability & Computer Technique Test Questions | Set 4

MCQs 1: In what direction does the phasor get rotated if it is multiplied by the operator ‘a’?

Anti clockwise

Clockwise

Gets rotated by 90° in the clockwise direction

Gets rotated by 90° in the anticlockwise direction

Answer Explanation

MCQs 2: The positive sequence current is always equal to ______________.

Always zero

1/3 of the negative sequence current

Negative sequence current

3 times the negative sequence current

Answer Explanation

MCQs 3: What is the value of the zero sequence current?

3 times the current in the neutral wire

1 / 3 times the current in the neutral wire

√3 times the current in the neutral wire

Equal to the current in the neutral wire

Answer Explanation

MCQs 4: In the manufacture of transformers, ANSI prescribes certain standards. What is this standard?

High voltage side should lead the low voltage side by 30° with Y - Δ or Y - Δ connections.

High voltage side should lead the low voltage side by 60° with Y - Δ or Y - Δ connections.

High voltage side should lag the low voltage side by 30° with Y - Δ or Y - Δ connections.

High voltage side should lag the low voltage side by 60° with Y - Δ or Y - Δ connections.

Answer Explanation

MCQs 5: For Y - Δ and Δ - Y transformers, the phase shift between the transformer windings is equal to “ n * 30° “. What does ‘n’ represent in the equation?

Number of windings

Number of turns

Turns ratio

Hour number

Answer Explanation

MCQs 6: Phase shift of symmetrical components happens in which among the following?

Delta - delta

Star – delta

Delta – star

Both (b) and (c)

All of these

Answer Explanation

MCQs 7: What is the value of negative sequence impedance?

Same as positive sequence

∞

Answer Explanation

MCQs 8: Zero sequence currents cannot flow in which of the following connections?

Delta

Star

Star – star

Both (b) and (c)

All of these

Answer Explanation

MCQs 9: What happens to the zero sequence currents, if the neutral in the Y connection is absent?

Minimum

Zero

Maximum

∞

Answer Explanation

MCQs 10: What are the types of unsymmetrical faults?

Single line to ground fault

Double line to ground fault

Line to line fault

All of these

None of these

Answer Explanation

MCQs 1: In what direction does the phasor get rotated if it is multiplied by the operator ‘a’?

MCQs 2: The positive sequence current is always equal to ______________.

MCQs 3: What is the value of the zero sequence current?

MCQs 4: In the manufacture of transformers, ANSI prescribes certain standards. What is this standard?

MCQs 5: For Y - Δ and Δ - Y transformers, the phase shift between the transformer windings is equal to “ n * 30° “. What does ‘n’ represent in the equation?

MCQs 6: Phase shift of symmetrical components happens in which among the following?

MCQs 7: What is the value of negative sequence impedance?

MCQs 8: Zero sequence currents cannot flow in which of the following connections?

MCQs 9: What happens to the zero sequence currents, if the neutral in the Y connection is absent?

MCQs 10: What are the types of unsymmetrical faults?

Related Topics