At first glance, hydroelectric thing is quite simple - poured water turns a generator, produces electricity. In fact, the modern hydroelectric power station - a system with very sophisticated equipment and thousands of sensors controlled by computers.
Today I will talk about that a few of the common people aware of the HPP.
1. GES - perhaps the only major engineering object, which begins to be operated long before the end of construction. In 2016 Ust-Srednekanskaya HPP not yet fully built the dam, not fully built computer room, and the first two of the four hydroelectric already produces electricity.
2. While hydroelectric power station built in its hydroelectric work time impellers, designed for low water pressure. When the dam is completed, the water pressure will rise and the time constant for the wheels replace high pressure with another form of blades.
3. Despite the fact that the construction of hydroelectric power station is very expensive, many hydroelectric pay off even before their being finished to the end. By the way, Ust-Srednekanskaya HPP sells electricity at 1.10 rubles per kWh.
4. Before you get on hydropower turbine, water twists using huge steel snail - volute. I was able to see and photograph it during the installation time. Now a giant snail is already in the thick of concrete.
To understand the design size, pay attention to the workers responsible for the installation of the volute.
5. Impeller hydroelectric always revolves at the same speed, providing a stable frequency of 50 hertz. It has always been a mystery as to maintain a stable speed. It turned out simply by changing the water flow. The blades, computer controlled, are constantly in motion, reducing and increasing the flow of water. The task of the system to achieve accurate rotation speed regardless of the force with which the generator shaft rotates (as it depends on the power output).
6. The voltage of a generator to be regulated by varying the driving voltage. This DC voltage is fed to the rotor magnet. The voltage that is generated by the stator winding depends on the strength of the magnetic field. In the photo above my head spinning rotor juggernaut.
7. Hydroelectric generator generates a voltage of 15.75 kV. Ust-Srednekanskaya HPP installed generators having a nominal power of 142.5 MW (142,500,000 W) and the current in the wires, which discharge generated electricity from the generator can reach 6150 A. Therefore, these wires, or rather the tire, have a huge cross-section and are enclosed here in such pipes.
Any switching at such currents becomes a big problem. Here is the simple switch. Of course, in the current six thousand amperes and a voltage of fifteen thousand volts it becomes quite difficult.
8. Up transformers usually stand in the street for the HPP machine room (for transmission to consumers voltage obtained from the generator increases more often up to 220 kV).
9. By wire transmission lines is transmitted not only to the electric power at a frequency of 50 Hz, but also information signals at high frequency. By using them, for example, it is possible to accurately determine the location of the accident on the power transmission line. In power plants and substations special filters a high-frequency signal are set. Surely, you have seen these things, but hardly know what they are.
10. All switching occurs at high voltage in the medium sulfur hexafluoride (sulfuryl fluoride having a very low electrical conductivity), so that the wire look as pipes and electrical more like plumbing. :)
p.s. Thanks to the staff of Ust-Srednekanskaya HPP Ilya Gorbunov and Vyacheslav Sladkevich (he pictured) for the detailed answers to my numerous questions, as well as company RusHydro for the opportunity to see with their own eyes the construction and operation of such a grand structures.
© Alexey Nadozhin
The main theme of my blog - Equipment for human life. I write reviews, share experiences, talk about all sorts of interesting things. My second project - lamptest.ru. I test LED lamps and help figure out which ones are good and which are not.