DGVCL Exam Paper (11-12-2011) If the excitation of a synchronous generator fails, it acts as a Induction generator Induction motor Synchronous motor Synchronous generator Induction generator Induction motor Synchronous motor Synchronous generator ANSWER EXPLANATION DOWNLOAD EXAMIANS APP if excitation of synchronous generator fails, operate as induction motor
DGVCL Exam Paper (11-12-2011) The transient stability of a power system can be improved by Increasing the turbine valve opening Single pole switching of circuit breakers Phase shifting transformer Excitation control Increasing the turbine valve opening Single pole switching of circuit breakers Phase shifting transformer Excitation control ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) People can interact with each other through any part of the world through video conferencing using Joystick Speaker Scanner Webcam Joystick Speaker Scanner Webcam ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) In a power plant, a reserve generating capacity which is not in service but is in operation is known as Spinning reserve Firm power Cold reserve Hot reserve Spinning reserve Firm power Cold reserve Hot reserve ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) In the protection of transformers, harmonic restraint is used to guard against Magnetizing inrush current Lightning Unbalanced protection Switching over voltages Magnetizing inrush current Lightning Unbalanced protection Switching over voltages ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Initial inrush of magnetizing currents have high component of even and odd harmonics.2nd - 63%3rd -26.8%4th- 5.1%5th- 4.1%6th- 3.77th-2.4
DGVCL Exam Paper (11-12-2011) An over excited synchronous motor draws current at Unity power factor Depends on nature of load Leading power factor Lagging power factor Unity power factor Depends on nature of load Leading power factor Lagging power factor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Over excitation : leading currentUnder excitation : lagging currentNormal excitation : current with unity PF (in phase current)