Electrical Machines A 8 pole, 50 Hz single phase induction motor is running at 690 rpm. Its slip with respect to forward field is 1.92 0.08 -0.08 -1.92 1.92 0.08 -0.08 -1.92 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The results of a slip test for determining direct axis (Xd) and quadrature axis (Xq) reactances of a star connected salient pole alternator are given below Phase values: Vmax = 108 V ; Vmin = 96 V Imax = 12 A ; Imin = 10 A Hence the two reactances will be Xd = 9Ω and Xq = 9.6Ω Xd = 10.8Ω and Xq = 8Ω Xd = 8Ω and Xq = 10.8Ω Xd = 9.6Ω and Xq = 9Ω Xd = 9Ω and Xq = 9.6Ω Xd = 10.8Ω and Xq = 8Ω Xd = 8Ω and Xq = 10.8Ω Xd = 9.6Ω and Xq = 9Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor has a rotor resistance of 0.002 Ω / phase. If the resistance is increased to 0.004 Ω / phase then the maximum torque will increase by 200% remain unaltered reduced to half increase by 100% increase by 200% remain unaltered reduced to half increase by 100% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The fall in speed of the DC generator due to increase in load can be corrected by increasing the excitation. cooling the armature. reducing the load voltage. increasing the input to the prime mover. increasing the excitation. cooling the armature. reducing the load voltage. increasing the input to the prime mover. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer cooling and insulating oil must be of low viscosity. low resistivity. low BDV. high viscosity. low viscosity. low resistivity. low BDV. high viscosity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor slots are slightly skewed in squirrel cage induction motor to increase the strength of rotor bars. provide ease of fabrication. decrease the amount of copper to be used. reduce the magnetic hum and locking tendency of rotor. increase the strength of rotor bars. provide ease of fabrication. decrease the amount of copper to be used. reduce the magnetic hum and locking tendency of rotor. ANSWER DOWNLOAD EXAMIANS APP
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