Electrical Machines A part an alternator winding consist of eight coils in series, each having an emf of 20 V rms induced in it. Coils are placed in successive slots and between each slot and the next, there is an electrical phase displacement of 30°. Find the emf of eight coils in series 86.91 V. 66.91 V. 56.91 V. 76.91 V. 86.91 V. 66.91 V. 56.91 V. 76.91 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-φ alternator has negligible stator resistance. A short circuit test is conducted on this alternator. At a particular speed, a field current of If1 is required to drive the rated armature current. If the speed of the alternator is reduced to half, the field current required to maintain rated armature current Would be equal to If1. Cannot be predicted due to insufficient data. Would be equal to If1/2. Woud be equal to 2If1. Would be equal to If1. Cannot be predicted due to insufficient data. Would be equal to If1/2. Woud be equal to 2If1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A single phase, 2 KV alternator has an armature resistance of 0.8 ohms and 4.94 ohms respectively. The voltage regulation of the alternator at 100 a load 0.8 loading power factor is 0%. 8.9%. 14%. 7%. 0%. 8.9%. 14%. 7%. 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 Stator mmf wave and resultant flux density. Rotor mmf wave and stator mmf wave. Stator mmf wave and resultant mmf wave. Rotor mmf wave and resultant flux density wave. Stator mmf wave and resultant flux density. Rotor mmf wave and stator mmf wave. Stator mmf wave and resultant mmf wave. Rotor mmf wave and resultant flux density wave. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The result of slip test on a 3-phase, 20 KVA, 400 V, 50 Hz connected salient pole alternator is given below- Phase value: Vmax = 100 V, Vmin = 96 V, Imax = 10 A and I min = 7 A. The direct and quadranature axis reactances are respectively 8.248 and 5.54 Ω. 14.28 and 9.60 Ω. 14.28 and 5.54 Ω. 8.248 and 9.60 Ω. 8.248 and 5.54 Ω. 14.28 and 9.60 Ω. 14.28 and 5.54 Ω. 8.248 and 9.60 Ω. ANSWER DOWNLOAD EXAMIANS APP