BEE BEE Bachelor of Electrical Engineering Power Systems Engineering Questions and Answers 2

Question 1

A 345 kV transmission line has a surge impedance of 400 ohms. What is the surge impedance loading (SIL) of the line?

Accepted Answer

297.6 MW

Answer

172.5 MW

Answer

400 MW

Answer

245.3 MW

Question 2

In a power system, what is the primary purpose of a bus coupler breaker?

Accepted Answer

To transfer load between two bus sections without interruption

Answer

To protect transformers from overvoltage

Answer

To isolate faulty generators

Answer

To regulate voltage at the distribution level

Question 3

Which type of fault in a three-phase power system typically produces the highest fault current?

Accepted Answer

Three-phase bolted fault

Answer

Single line-to-ground fault

Answer

Line-to-line fault

Answer

Double line-to-ground fault

Question 4

What does the equal area criterion determine in power system transient stability analysis?

Accepted Answer

Whether a synchronous machine will remain in synchronism after a disturbance

Answer

The steady-state power transfer limit of a transmission line

Answer

The optimal load dispatch between generators

Answer

The voltage regulation of a transformer under load

Question 5

A generator has a transient reactance of 0.25 per unit and delivers 1.0 per unit power at unity power factor. What is the internal voltage behind transient reactance?

Accepted Answer

1.03 per unit

Answer

1.25 per unit

Answer

0.75 per unit

Answer

1.50 per unit

Question 6

In economic load dispatch, what condition must be satisfied for optimal generation allocation among multiple units?

Accepted Answer

The incremental cost of all participating units must be equal

Answer

Each unit must operate at its maximum efficiency point

Answer

Total generation must equal total losses

Answer

All units must share load equally