1. PRINCIPLES OF OPERATION
A/C GENERATORS
PRINCIPLES OF
OPERATION

2. OPERATION
The generator converts mechanical energy into electrical energy.
Mechanical energy is given by means of a drive belt, from the crankshaft.

3. MAJOR COMPONENTS Housing ( drive and rear) Rotor Stator Rectifier
Brush Assembly
Voltage Regulator (Integral)
Drive Pulley

4. Principles

5. HOUSINGS
Drive Housing: Supports the front of the rotor shaft, as a large bearing pressed or flanged bolted. Has mounting holes for installation on to engine via a bracket.
End Housing: Anchoring point for Brush holder, Regulator, Rectifier and Stator assembly. Also supports the rear of the rotor shaft via small bearing.

6. Housings

7. ROTOR
Purpose: The rotor is used to create a magnetic field, and rotate that magnetic field inside the stator at varying speeds.
Parts
Projections (2) North and South
Rotor shaft
Field Windings
Slip Rings

8. ROTOR CONSTRUCTION

9. BRUSHES AND SLIP RINGS
Purpose: To direct current to the rotating field windings
Connections
F (field terminal) External
Voltage regulator (insulated)
Exciter Diodes

10. Brushes and Slip Rings

11. STATOR Purpose: To collect the magnetic field created by the rotor
Parts
3 or 4 phase windings
Laminated steel frame
Winding types
Wye
Delta

12. Stator Construction

13. STATOR
The Stator produces a Analog Signal, that produces Alternating Current
Output is determined by
Magnetic field strength
Rotor speed
Winding type (delta or wye)
Winding length
Number of phases (windings)

14. Stator Operation

15. Rectification Purpose: Change the current from AC to DC Parts
Diodes: Three positive and three negative.
Exciter Diodes: Controls field current at Startup giving us full field current after start-up.
Heat Sink: Aluminum webbing linking diodes to end frame.

16. Rectification Parts

17. Rectification Operation

18. Voltage Regulator
Purpose: To control the current flow through the field windings.
Process: Switches current flow on and off in the field windings, by watching line voltage

19. Regulation