List of practice Questions

The Y-bus matrix of a 100-bus interconnected system is 90% sparse. Hence the number of transmission lines in the system must be:
Consider a feedback system with gain margin of about 30. At what point does the Nyquist plot cross the negative real axis?
Efficient Line-Commutated Converter (LCC) HVDC converters generally use:
Which of the following circuit breakers take minimum time in installation?
Which component of gas turbine power plant is the main cause of its low efficiency?
A protection system engineer is planning to provide complete protection for a 3-phase transmission line. He can achieve this by:
For a given power system, its zero and maximum regulation will occur at the impedance angle of:
Which of the following is not a requirement for site selection of a hydroelectric power plant?
Fault calculations using computer programs are usually done by:
The incremental cost characteristics of two generators delivering a total load of 200 MW are as follows: \[ C_1 = 4.01 + 0.1P_1 \, \text{Rs/MWh} \quad \text{and} \quad C_2 = 1.60 + 0.2P_2 \, \text{Rs/MWh} \] What should be the values of \(P_1\) and \(P_2\) for economic operation?
If all the sequence voltages at the fault point in a power system are equal, then the fault is:
The magnitude of zero sequence current of a generator for LG fault is 2.4 p.u. The current through the neutral during fault in p.u. is:
The main objective of Load Frequency controller is to apply control of:
A 100 kVA Generator has 10% reactance. Its short circuit kVA is:
Two insulator discs of identical capacitance value C make up a string for a 22kV, 50Hz, single-phase transmission line. If the pin-to-earth capacitance is also C, then the string efficiency is:
The Surge Impedance of a 3-Phase 400kV transmission line is 400ohm. The Surge Impedance Loading (SIL) is:
Starting torque in the case of a 3-phase synchronous motor is:
Breakdown torque in a 3-phase induction motor of negligible stator impedance is:
What is the frequency of rotor current of a 50Hz induction motor operating at 2% slip?
A 3-phase induction motor is operated with rotor blocked, its power factor is:
The supply voltage to an induction motor is reduced by 10%. By what percentage approximately will the maximum torque decrease?
In a short transmission line, voltage regulation is zero only when the load at the receiving end operates at:
The direction of rotation of a DC series motor can be reversed:
(I) By interchanging supply terminals
(II) By interchanging field terminals
A 20KVA, 2000/200 V single-phase transformer has name-plate leakage impedance of 8%. The voltage required to be applied on the HV side to circulate full load current with the LV winding short-circuited will be:
A 4kVA, 400V/200V single-phase transformer has resistance of 0.02 pu and reactance of 0.06 pu. The resistance and reactance referred to HV side are: