Electrical Machines For a fault at the terminal of a synchronous generator, the fault current is maximum for a 3 - phase to ground fault. line to line fault. 3 - phase fault. line to ground fault. 3 - phase to ground fault. line to line fault. 3 - phase fault. line to ground fault. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 4, 6 1, 2, 5 1, 2, 6 1, 3, 5 1, 4, 6 1, 2, 5 1, 2, 6 1, 3, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series generator is connected in series to a feeder having 0.5Ω resistance to boost the voltage. The induced voltage is given by Eg = 0.6Ia, Ra = 0.2Ω and Rs = 0.3Ω. Find the voltage boosted by the generator, when delivering 400 Amp? 90 V. 40 V. 30 V. 60 V. 90 V. 40 V. 30 V. 60 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Slip speed is the sum of synchronous and rotor speeds. difference of actual rotor speed and synchronous speed. difference of synchronous speed and actual rotor speed. half of the sum of synchronous and rotor speeds. sum of synchronous and rotor speeds. difference of actual rotor speed and synchronous speed. difference of synchronous speed and actual rotor speed. half of the sum of synchronous and rotor speeds. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an AC servomotor has one of its winding excited by AC, then voltage measured at the other winding with rotor running will be zero. constant independent of speed. proportional to rotor speed. proportional to square of rotor speed. zero. constant independent of speed. proportional to rotor speed. proportional to square of rotor speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC motor is laminated to reduce the inductor. to reduce the mass. to reduce the hysteresis loss. to reduce the eddy current loss. to reduce the inductor. to reduce the mass. to reduce the hysteresis loss. to reduce the eddy current loss. ANSWER DOWNLOAD EXAMIANS APP