THE CENTRAL HIGH FALL HYROELECTRIQUE

DEFINITION

Hydroelectric a high fall is a plant which uses a drop of water worth more than 50 m. Usually, this fall is equipped with Pelton turbines, ie turbines tell action. This is the direct action of water on the buckets of the wheel which produces mechanical energy. The highest waterfall in use is that of Reisseck Austria 1765m.

COMPOSITION

Central  is usually composed of :

• water intake
• room of formal charge
• penstock
• building production
• channel leakage

LED WATER

The water is collected once dessablée by settling in a room. It is then charged to conduct forced. The works to sing-ing to operate without air inlet. The pipe is usually welded steel, driving is done at the factory in sections 6 to 12 m checked and tested. It is then assembled in place. She is buried or aerial. It must be protected against corrosion, against the erosion of sand transported and against the phenomena of electrical erosion. In fact, in the basement of circulating currents due to geology, to the natural chemical, electrical lines nearby rail etc ...

The conduct may be steel quickly pierced by these currents, it raises cathodic protection. Driving may be equipped with a valve on outbreak-speed automatic or a system of differential pressure to bring the books to safety in case of problems. Some pipes are made of resin polyerter, concrete others are being built of wood for specific cases.

WATER COLLECT

Water is collected through a water intake. The latter is either integrated into the dam or along the water. In this case, often with a perforated grilles auto nettoyanteou bars. The major problems are: the protection of fish, the problems of freezing, the sand, the bodies floating and flooding.

ENGINES ROOM

Driving is equipped with a foot valve which cuts the water during periods of arrest or entreteint. The Pelton turbine is a bucket wheel that rotates on an axis. The output speed of the water on the injector depends on the head. The périphériquede wheel speed is half that of water. This difference crait energy. The injector is composed of a nozzle and a poniteau. The unit is adjustable and control water flow. In case of power from the grid allows a deflector to divert the jet instantly to avoid the excitement of the machine. The turbine is then closed slowly to avoid water hammer in the pipe. On the curve of the excess so that the maximum peak Michaud called acceptable for driving.