1) What information does the swing curve provide? a. Stability of the system. b. Performance of the machine c. The rotor performance d. All of these e. None of these
|
||||
2) What are the main applications of the swing curves? a. Designing the rotor field windings b. Designing the protective devices c. Used to limit the size of the machine d. All of these e. None of these
|
||||
3) What will be the inertia constant H, for a water wheel generator having a speed less than 200 rpm? a. 2 - 4 b. 2 - 3 c. 1 - 2 d. 5 - 6
|
||||
4) What is power angle equation of synchronous machines? a. An equation between electrical power generated to the angular displacement of the rotor b. An equation between mechanical power generated to the angular displacement of the rotor c. An equation between electrical power generated to the angular displacement of stator windings d. An equation between mechanical power generated to the angular displacement of stator windings
|
||||
5) At what value of ‘δ’ the maximum power transfer takes place? a. 45 ° b. 90 ° c. 120 ° d. 180 °
|
||||
6) What is the range of ‘δ’ for stable operation? a. 0° < δ < 45° b. 45° < δ < 90° c. 0° < δ < 90° d. 0° < δ < 120°
|
||||
7) Which among the following methods are used to improve steady state stability? a. Reducing the reactance between the transmission and receiving points. b. By using bundled conductors. c. By increasing the excitation of generator or motor or both. d. All of these e. None of these
|
||||
8) Why are the series capacitors used? a. Improve the voltage b. Reduce the fault level c. Compensate for line inductive reactance and improve the stability of the power system. d. Improves the power factor
|
||||
9) Which stability information is obtained from the equal area criterion? a. Absolute stability b. Transient stability c. Steady state stability d. Both (b) and (c) e. All of these
|
||||
10) For which among the following cases is the equal area criterion of stability used? a. One machine and infinite bus bar b. No load on bus bar c. Many machines and infinite bus bar d. All of these e. None of these
|
||||
11) What are the common assumptions made for the equal area criterion? a. The transmission line and machine resistances are neglected. b. Rotor speed of the machine is constant c. Mechanical input remains constant. d. All of these e. None of these
|
||||
12) Which among these cannot be determined from equal area criterion? a. Critical clearing angle b. Critical clearing time c. Transient stability limit d. Both (a) and (b) e. All of these
|
||||
13) Which among these is related to the critical clearing time of a fault in a power system? a. Transient stability limit b. Steady state stability limit c. Frequency limit d. All of these e. None of these
|
||||
14) With the use of high speed circuit breakers, which among the following stability is increased? a. Steady state stability b. Transient stability c. Frequency stability d. All of these e. None of these
|
||||
15) What will be the penalty factor for a unit, if the generating station is located very close to load centre? a. Zero b. Almost equal to unity c. The penalty factor is negative d. The value is very high
|
||||
16) How is the voltage and frequency controlled in automatic generation control? a. By controlling the excitation b. By controlling the turbine action c. Turbine speed control for voltage and excitation control for frequency d. Excitation control for voltage and turbine speed control for voltage.
|