Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 7. 12. 4. 3. 7. 12. 4. 3. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature shaft must be able to with stand Twisting stains due to transmission of torque. Any unbalanced magnetic pull on the armature core. Bending moment due to weight of the armature. All of these Twisting stains due to transmission of torque. Any unbalanced magnetic pull on the armature core. Bending moment due to weight of the armature. All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Induction motors normally use cast aluminium rotor because aluminium is easy to cast owing to its low melting point and is easily available. of low resistivity. cheaper in cost. lighter in weight. easy to cast owing to its low melting point and is easily available. of low resistivity. cheaper in cost. lighter in weight. 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 14.28 and 5.54 Ω. 8.248 and 9.60 Ω. 14.28 and 9.60 Ω. 8.248 and 5.54 Ω. 14.28 and 5.54 Ω. 8.248 and 9.60 Ω. 14.28 and 9.60 Ω. 8.248 and 5.54 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When maximum flux density is constant, the eddy current losses are proportional to V2 V f f2 V2 V f f2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In an ideal DC generator the regulation is zero. positive. low. high. zero. positive. low. high. ANSWER DOWNLOAD EXAMIANS APP