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Some background: I came from commercial electrical to work for a private utility in their hydropower division. Our facilities are all "alternative" energy so they're very small by traditional generation standards. The plant in these photos consists of two horizontally mounted 10 megawatt, 4160 volt synchronous generators running at 120 RPM.

The first picture is the generator itself. The three conduits coming out of the top are the 4,160V feeder conductors. The rotor field conductors enter on the other side. This unit is air cooled, with ambient air being drawn through the screens on the face and forced out through the two centrifugal fans mounted on the top of the unit.

The cylinder to the right of the generator is the thrust bearing: the turbine is further to the right of that, and the action of the water against the turbine pushes the whole shaft towards the generator. The thrust bearing keeps this force off the generator. (The three conduits in the foreground are the feeders for our second generator, identical to the one in the picture.) - (see below)

The second picture is the casing on the turbine (taken from above looking down). The turbine itself consists of a runner blade that looks like a massive boat propeller, located under the shell on the right, and is responsible for spinning the turbine shaft. The water flow through the runner blade is controlled by wicket gates, which rotate open or closed.

Each of the gray cylinders on the left represents the end of a wicket gate. The gray cylinders are rotated by the movement of those angled arms. The arms are all turned in tandem by that common ring they are connected to.

An interesting note: Sometimes debris passes through the unit and can get caught between the individual wickets. If you tried to close the gates on the debris, it could damage the wicket. To keep that from happening, you can see how one side of each angled arm is tapered to a "V", this is actually a shear point; designed to fail before the wicket gate does. - (see below)

The third picture is the shaft coupling between the turbine shaft and the generator shaft. This is normally under a guard, but exposed for repair. The orange end of the shaft is the turbine shaft, the turbine is being driven by river water on the other side of that wall. The gray end of the shaft is the generator shaft.

On the left you can see the edge of the thrust bearing that was in picture 1. The bolts in those pictures are called "Super Bolts", they allow the bolts to handle a total torque of several million pounds, but each bolt can be properly tightened by hand. - (see below)

And the fourth picture is our our switchboard with our control and protective relaying scheme. All the black rectangles are precisely calibrated relays that monitor various conditions and sound alarms or will shut the machines down automatically depending on the condition.

While this was state-of-the-art when the plant was built, it will eventually all be replaced by a PLC system that could sit on a table-top. If you look closely you can see that one unit is running and one unit is offline: For "NO.1 GENERATOR" the two white lights and the red light indicate a unit in "parallel" which means it's sychronized with the utility and generating power.

Now, far to the right where the yellow tag is, you can just make out one green light and two white lights. This indicates the unit is "stopped" and thus offline and in a safe condition. In our plant, red actually means "go". - (see below)

Hope you enjoyed it. I'll try to get some pictures of our older generating plants for you guys next. They're turn-of-the-century systems and pretty wild in their own right.

-John