Electrical Machines If direct axis reactance Xd and quadrature axis reactance Xq are equal, then reluctance power is minimum maximum zero All of these minimum maximum zero All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Torque angle of a synchorous machine operating from a constant voltage bus is usually defined as the space angle between Rotor mmf wave and resultant flux density wave. Stator mmf wave and resultant mmf wave. Stator mmf wave and resultant flux density. Rotor mmf wave and stator mmf wave. Rotor mmf wave and resultant flux density wave. Stator mmf wave and resultant mmf wave. Stator mmf wave and resultant flux density. Rotor mmf wave and stator mmf wave. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The emf induced in a conductor rotating in a bipolar field is None of these DC. both of above. AC. None of these DC. both of above. AC. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer the magnetic coupling between the primary and secondary winding can be increased by increasing the number of turns. using transformer oil of better quality. using the magnetic core of low reluctance. using soft material for winding. increasing the number of turns. using transformer oil of better quality. using the magnetic core of low reluctance. using soft material for winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 4 1, 3 1, 4 2, 3 2, 4 1, 3 1, 4 2, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer core is made up of a silicon steel laminations which has maximum flux density 1 Tesla. If it was cold rolled grain oriented its flux density increases to 1.6 Tesla. What is the saving in core size or area due to cold rolled grain oriented process? 38% 40% 60% 68% 38% 40% 60% 68% ANSWER DOWNLOAD EXAMIANS APP