GETCO Exam Paper (22-07-2015) For eliminating 7th harmonics from generated EMF in alternator the fractional pitch must be 5\6 2\3 7\8 6\7 5\6 2\3 7\8 6\7 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP fractional pitch = Cos( α/2)α is obtain from: (nα/2)=90˚ where n is harmonicα=25.7143˚fractional pitch=6/7
GETCO Exam Paper (22-07-2015) In synchronous motor, V-curve is a graph of Armature current Vs Field current Armature current Vs power factor Armature current Vs active power Armature current Vs reactive power Armature current Vs Field current Armature current Vs power factor Armature current Vs active power Armature current Vs reactive power ANSWER EXPLANATION DOWNLOAD EXAMIANS APP v curve: armature current → field currentInverted V curve: power factor → field current
GETCO Exam Paper (22-07-2015) What is the surge impedance loading of 400 kV line with surge impedance given as 160 Ω 250 MW 400 MW 1000 kW 1000 MW 250 MW 400 MW 1000 kW 1000 MW ANSWER EXPLANATION DOWNLOAD EXAMIANS APP SIL = (kV)²/Z₀
GETCO Exam Paper (22-07-2015) Earth wire on EHV overhead transmission line is provided to protect the line against lightning surge corona effect excessive fault voltages switching surge lightning surge corona effect excessive fault voltages switching surge ANSWER DOWNLOAD EXAMIANS APP
GETCO Exam Paper (22-07-2015) The Y bus matrix is a sparse matrix because … no of lines are less bus incidence matrix is a sparse matrix lines are connected to less no. of buses Y primitive is a sparse matrix no of lines are less bus incidence matrix is a sparse matrix lines are connected to less no. of buses Y primitive is a sparse matrix ANSWER DOWNLOAD EXAMIANS APP
GETCO Exam Paper (22-07-2015) The constraints that are to be met with while solving UC problem are all are correct Minimum up time Spinning reserve Minimum down time all are correct Minimum up time Spinning reserve Minimum down time ANSWER DOWNLOAD EXAMIANS APP
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