Electrical Machines An inverted V curve of synchronous motor shows variation of supply voltage and excitation current at constant load. power factor and DC excitation at constant load. supply voltage and field current at constant excitation. power factor and supply voltage during hunting. supply voltage and excitation current at constant load. power factor and DC excitation at constant load. supply voltage and field current at constant excitation. power factor and supply voltage during hunting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Sparkless commutation can be achieved by employing inter poles. compensating winding. high resistance carbon brushes. any one or more of the above methods. inter poles. compensating winding. high resistance carbon brushes. any one or more of the above methods. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generator on no-load, the air gap flux distribution in space is triangular. flat topped. sinusoidal. pulsating. triangular. flat topped. sinusoidal. pulsating. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction in a DC machine is in the same direction as the main poles. makes an angle of 90° with the main pole axis. is in direct opposition to the main poles. makes an angle with the main pole axis which is load dependent. is in the same direction as the main poles. makes an angle of 90° with the main pole axis. is in direct opposition to the main poles. makes an angle with the main pole axis which is load dependent. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 ,V 15 , kW 100 rpm shunt motor with armature resistance of 0.25 , W has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is 36.36% decrease 18.18% increase 36.36% increase 36.36% increase 36.36% decrease 18.18% increase 36.36% increase 36.36% increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum efficiency will occur, when copper loss is_______to iron loss? any of the above less than equal to greater than any of the above less than equal to greater than ANSWER DOWNLOAD EXAMIANS APP