DGVCL Exam Paper (11-12-2011) In the protection of transformers, harmonic restraint is used to guard against Lightning Magnetizing inrush current Switching over voltages Unbalanced protection Lightning Magnetizing inrush current Switching over voltages Unbalanced protection 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) If the voltage at the two ends of a line are 132 kV, and its reactance is 40 Ω, the stability limit of the line is 500 MW 217.8 MW 435.6 MW 251.5 MW 500 MW 217.8 MW 435.6 MW 251.5 MW ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The positive and negative sequence impedance of a transmission line are Infinite Different Zero Equal Infinite Different Zero Equal ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) At time t= 0+ , with zero initial condition, which of the following acts as a short circuit? Conductor Capacitor Voltage source Resistor Conductor Capacitor Voltage source Resistor ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The main advantage of using fractional pitch winding is to refuce Amount of copper in the winding Harmonics in the generated emf Size of the machine Cost of the machine Amount of copper in the winding Harmonics in the generated emf Size of the machine Cost of the machine ANSWER EXPLANATION DOWNLOAD EXAMIANS APP due to fractional pitch EMF can be approximately made into sine wavelosses due to harmonics reducedsaving in conductor materialmechanical strength of coil is increased.
DGVCL Exam Paper (11-12-2011) Transposition of transmission line is done to Reduce skin effect Reduce corona Reduce line loss Balance line voltage drop Reduce skin effect Reduce corona Reduce line loss Balance line voltage drop ANSWER DOWNLOAD EXAMIANS APP
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