Regarding its design, any hydro generator has the following components:
- Ancillary components
A. Stator's main parts are:
- Stator core
- AC three phased winding
- Stator frame (fastening and protection role)
- made by laminations/sheet plates;
- stator core fixed on the stator frame using dovetail keys;
- there are radial ducts for cooling and ventilation reasons;
- in order to prevent vibrations during the operation, it is fastened with prestressed clamping bolts through the core and steel plates on bothe sides of the core (upside and downside).
- made by copper wire or copper bars;
- Y connection;
- is the winding connected to the network.
- made by steel plates or welded parts;
- represents the link between the fastening devices and the foundation, the dovetail keys of the stator core, the hydraulic jacking devices.
B. Rotor's main parts are:
- pole body
- pole coil (D.C.)
- rotor rim
- damper winding (cage type)
- made by laminations/sheet plates.
- individual coils made by copper wire or bars;
- by serial link of the pole coils, we obtain alternate poles N-S-N-S (heteropolar inductor).
- made by massive steel or by plates. The rotor could be massive or could have an umbrella type design.
- cage type winding with bars placed into the spaces of the pole body. These bars are shortcircuited at both ends by other bars.
C. The main ancillary components of a hydro generator are the brush gears and the slip rings. The terminals of the rotor winding (the beginnings and the endings of the polar coils) are connected to the slip rings, which, through the brush gears, are connected to the DC source (excitation system).