Electrical Machines Interview Questions

1. What is a Transformer2. How are Primary and secondary windings of a Transformer connected3. Name different types of Transformer based on Number of windings4. Where Transformers are applicable5. How does electrical energy transfer takes place in Transformers6. Why does Transformers are know as to have high efficiency7. What are the two general type of Transformers based on in which manner windings Are Wound

8. What is leakage flux9. What is the need to reduce leakage flux and how can we do this in both core and shell type

Transformers10. For low power levels and high power levels which type of transformers are preferred11. What do you mean by heating and cooling of transformers12. What is the principle involved in working of a transformer13. What are the properties of a ideal two winding transformer14. How does the transfer of impedance takes place in transformers15. What are Transformers16. What are Transformer losses

17. What is B-H curve18. What is the Emf equation in a Transformer19. What are Open and Short circuit tests of a Transformer20. What is the purpose of Auto-Transformer21. How does wattmeter connected on H.V side records the Ohmic losses on L.V side also

22. How can we express volts, amperes, and ohms etc in Per Unit Values what is it Necessary23. What is voltage regulation of a Transformer24. Why do we perform Polarity tests on Transformers25. Why do we perform load test or Sumpner’s test on Transformers26. What is efficiency and condition for maximum efficiency in a transformer27. What are the conditions to be satisfied for parallel operation of transformers28. What are Stray load and Dielectric losses29. What are Hysteresis and Eddy current losses30. What are Tap changers on Transformers and what is their need31. What is need of Induction regulators in Transformers32. What are Three Phase Transformers give their four Standard connections33. What factors causes Noise in a Transformer and How can we reduce it34. What is Electromagnetic energy conversion Principles

35. What is Coupling Field reaction36. What is a motor and the principle involved in the motor37. What is the generator and the principle involved in generator38. What is Electromagnetic or Interaction torque39. What is Reluctance or Alignment toque40. What are the differences between Dc and Ac machines41. What does the stator consists of42. What does the Rotor consists of43. What is Pole-Pitch44. What are Electrical and Mechanical degrees45. What is flux per pole46. What are full pitched and short pitched coils47. What are Synchronous and Induction machines48. What is Synchronization49. Explain the Armature and Field windings of Synchronous machine50. Explain the Stator and Rotor windings of Induction Machines51. How does the E.M.F generation takes place in Dc machine52. How are Synchronous machines classified53. How are Inductions Machines classified54. What are Slip ring Induction machines55. What are Squirrel cage Induction machines56. What are Salient pole Synchronous Machines57. What are Non Salient pole Synchronous Machines58. What is the difference between single phase and Poly phase Synchronous Machines

59. What is the difference between single phase and Poly phase Induction machines60. What is Synchronous speed61. What are heating and cooling curves of Induction machines62. What are Synchronous compensators63. Mention the applications of Synchronous generators and motors64. mention the applications of Induction motors and generators65. What is starting torque66. What is pull-out-torque67. What is pull in torque68. What are different cooling methods69. What are Mechanical losses70. What are speed torque characteristics71. What are different methods of Machines72. Explain Self excitation73. Explain Separate excitation74. What is Armature Reaction75. What are Stationary parts of a D.C motor76. What are rotary parts of D.C motor77. What is a commutator78. What is commutator action79. What is rocker80. What are Brushes81. What are Interpoles82. What is Yoke83. What is field poles84. What is Field windings85. What is Compensating Windings86. What is Armature core

87. What is armature windings88. What is Shaft89. What are Ratings of a Motor90. What is Cross Magnetization91. What is De-Magnetization92. What are the effects of Armature reaction93. What are the different methods employed in limiting Armature reaction94. What are the effects of Brush shifts95. What are different operating characteristics of D.C generators96. What is Generating mode97. What is Motor mode98. What is Magnetization curve99. What are Cumulative compound generators100. What are Shunt Generators101. What are series Generators102. What are operating characteristics of D.C Motors103. What is D.C compound Motor104. What are the necessary conditions to be obtained for staring of a Motor105. What are stators106. What is external resistance107. What factors influence the speed of a D.C motor108. How does the speed control of motors takes place109. What do you mean by Speed Regulation110. What are shunt motors111. What are series motors112. What is Ward Leonard method1113. What is Armature voltage control method

114. How does speed control can be obtained in motors by using SCR’S115. How does testing of D.C machines takes place116. What is Direct method of testing117. What is Swinburne’s or indirect method of testing118. What is Regenerative or Hopkinson’s method of testing119. What is Brake test120. What are Rotating Amplifiers121. What is Power Factor122. What are Permanent magnet Dc Motors123. What are the two types of Armature windings124. What are the Advantages of stationary armature125. What happens if the Armature coil is opened126. What happens if the field coil is opened127. Why does sparking occurs in a commutator128. What are the advantages of Non salient or cylindrical rotor over Salient pole rotor129. What is pitch factor130. What is breath factor131. What are Harmonics132. How can we reduce the effect of harmonics133. What is Tooth Ripple134. What are the methods of excitation of a Synchronous machines135. What is static excitation System136. What is brushless excitation system137. How does cooling of Synchronous machines takes place138. What is voltage regulation of an Alternator

139. What are the different methods of finding voltage regulation140. What is m.m.f method141. What is potier method142. What is A.S.A method143. What is synchronous Impedance method144. What is two reaction theory145. What is slip test146. How can we determine Xd and Xq147. What does Synchronisation of Alternators mean148. What are different methods of Synchronising alternators149. What is Dark lamp method150. What is Bright lamp method151. What is Synchroscope method152. What is Synchronizing power153. What is Synchronizing Torque154. What is synchronizing Current155. Can you explain the Parallel operation of Alternators156. What is the effect of change in excitation157. What is the effect of change in input power158. Explain the operation of alternators on infinite bus159. How does load gets affect with speed in Synchronous machines160. What is the effect of field excitation in Synchronous motor161. What are V and inverted V curves162. What is normal excitation163. What is under excitation

164. What is Over excitation165. What is Synchronous condenser166. What are the different methods of starting of Synchronous motors167. What is a pony motor168. Why single phase Induction motors are not self starting169. Why poly phase induction motors are self starting170. What is meant by Cogging in Induction motors171. What is meant by Skew in Induction motors172. What is meant by Crawling in Induction motors173. What is double field revolving Theory174. What is Cross field revolving theory175. What are different stating methods of induction moto