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) An over excited synchronous motor draws current at Leading power factor Depends on nature of load Lagging power factor Unity power factor Leading power factor Depends on nature of load Lagging power factor Unity power factor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Over excitation : leading currentUnder excitation : lagging currentNormal excitation : current with unity PF (in phase current)
DGVCL Exam Paper (11-12-2011) A Mho relay is a Directional restrained over current relay Voltage controlled over current relay Directional restrained over voltage relay Voltage restrained directional relay Directional restrained over current relay Voltage controlled over current relay Directional restrained over voltage relay Voltage restrained directional relay ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The bus bar zone faults are generally Three phase short ciruits Phase to phase faults Double line to ground faults Single line to ground faults Three phase short ciruits Phase to phase faults Double line to ground faults Single line to ground faults 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 Firm power Spinning reserve Cold reserve Hot reserve Firm power Spinning reserve Cold reserve Hot reserve ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Which motor is used to start heavy loads? Shunt motor Differentially compounded motor Cumulatively compounded motor Series motor Shunt motor Differentially compounded motor Cumulatively compounded motor Series motor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Torque in d.c motor = k* φ * IaIn series motor φ α IaTα I²starting torque of dc series motor is high
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