Electrical Machines A 500 V, 120 KW, 50 Hz, star connected synchronous motor operating at 0.8 power factor leading has full load efficiency of 91%. The armature resistance is equal to 0.08Ω. The magnitude of armature current is nearly equal to 127 A. 190 A. 173 A. 240 A. 127 A. 190 A. 173 A. 240 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If Pi and Pc represent core and full load copper loss respectively, the maximum KVA delivered to load corresponding to maximum efficiency is equal to rated KVA is Pi/Pc Pc/Pi (Pi/Pc)2 √(Pi/Pc) Pi/Pc Pc/Pi (Pi/Pc)2 √(Pi/Pc) ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 25 Hz 100 Hz 0 Hz 50 Hz 25 Hz 100 Hz 0 Hz 50 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In salient pole synchronous machine, maximum power occurs at a load angle of less than 90° Greater than 90° 0° 90° less than 90° Greater than 90° 0° 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following methods of speed control is not affected through stator side? Change of supply voltage. Change of supply frequency. Change of number of pole. Change of rotor resistance. Change of supply voltage. Change of supply frequency. Change of number of pole. Change of rotor resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of IM the torque is directly proportional to slip2. inversely proportional to slip. inversely proportional to √slip. directly proportional to slip. directly proportional to slip2. inversely proportional to slip. inversely proportional to √slip. directly proportional to slip. ANSWER DOWNLOAD EXAMIANS APP