Electrical Machines

Completa manuale gratuito di macchine elettriche con diagrammi e grafici

An electrical machine is a device which converts mechanical energy into electrical energy or vice versa. Electrical machines also include transformers, which do not actually make conversion between mechanical and electrical form but they convert AC current from one voltage level to another voltage level.

This free application serves to both engineering students and professionals.

There are basically two types of electrical machines :

Transformers:

Transformers are used to transfer electrical energy from one circuit to another using magnetic flux. They do not contain any moving parts.

Motors and generators:

Motors convert electrical energy to mechanical energy and generators do the opposite. Motors and generators are again divided into AC and DC based on the type of the electrical energy they use or generate.

AC machines are again classified as synchronous machines if they maintain synchronous speed or induction machines if the rotors rotate at less than synchronous speed.

Some of the topics Covered in the app are:

1. Poly-phase AC Machines

2. Classification of A.C. Motors

3. Construction of A.C Motor

4. Phase-wound Rotor

5. Production of Rotating Field

6. Three-phase Supply

7. Relation Between Torque and Rotor Power Factor

8. Starting Torque of induction motor

9. Torque, Rotor E.M.F. and Reactance Under Running Conditions

10. Condition for Maximum Torque Under Running Conditions

11. Relation Between Torque and Slip

12. Full-load Torque, Starting torque and Maximum Torque

13. Torque/Speed Curve

14. Current/Speed Curve of an Induction Motor

15. Plugging of an Induction Motor

16. Complete Torque/Speed Curve of a Three-Phase Machine

17. Measurement of Slip

18. Power Stages in an Induction Motor

19. Torque, Mechanical Power and Rotor Output

20. Induction Motor Torque Equation

21. Analogy with a Mechanical Clutch and D.C. Motor

22. Sector Induction Motor

23. Magnetic Levitation

24. Induction Motor as a Generalized Transformer

25. Equivalent Circuit of the Rotor and Induction Motor

26. Power Balance Equations

27. Circle Diagram for a Series Circuit

28. Circle Diagram for the Approximate Equivalent Circuit

29. Determination of G0 and B0

30. Blocked Rotor Test

31. Construction of the Circle Diagram

32. Starting of Induction Motors

33. Starting of Slip-ring Motors

34. Starter Steps

35. Crawling and Cogging or Magnetic Locking

36. Double Squirrel Cage Motor

37. Speed Control of Induction Motors

38. Three-phase A.C. Commutator Motors

39. Three-phase A.C. Commutator Motors

40. Standard Types of Squirrel-cage Motors

41. Types of Single-Phase Motors

42. Single-phase Induction Motor

43. Double-field Revolving Theory

44. Making Single-phase Induction Motor Self-starting

45. Equivalent Circuit of a Single-phase Induction Motor Without Core Loss

46. Types of Capacitor - start Motors

47. Capacitor Start-and-Run Motor

48. Shaded-pole Single-phase Motor

49. Repulsion Type Motors

50. Repulsion Principle

51. Compensated Repulsion Motor

52. A.C. Series Motors

53. Universal Motor

54. Speed Control of Universal Motors

55. Unexcited Single-phase Synchronous Motors

56. Basic Principle and Stationary Armature of Alternator

57. Details of Construction

58. Damper Windings, Speed and Frequency

59. Armature Windings, Concentric or Chain Windings and Two-Layer Winding