The device of a modern high-voltage substation is impressive, but it is almost impossible for an ordinary person to get there. I was able to visit the high-voltage substation and the control center for electric networks in Moscow.
High-voltage substation 220/20 kV Abramovo is located on Okruzhnaya Street.
Such a substation is the third stage in the delivery of electricity to the consumer:
1. The power plant generates a voltage of 500 or 750 kilovolts.
2. The first high-voltage substation will convert it to 220 kilovolts.
3. The second high-voltage substation converts 220 to 20 kilovolts.
4. Small substations convert 20 to 10 or 6 kilovolts.
5. Transformer booths in the courtyards convert 6 or 10 kilovolts to 230 volts.
These high voltages are needed to transmit very high electrical power over relatively thin wires (the higher the voltage, the thinner the wire at the same power).
The voltage of 220 kilovolts is supplied to the substation using XLPE insulated cables. Each phase is a separate cable with a diameter of 125 mm. These cables are laid underground. This is what a 220-kilovolt input looks like.
A monstrous complete switchgear (GIS) is just an analogue of a switchboard in an apartment, with the only difference that the voltage and current are a thousand times higher.
Two input three-phase cables come here and three cables leave for three transformers standing at the substation.
SF6 gas is used as insulation ( http://ru.wikipedia.org/wiki/Элегаз).
Gas analyzers are constantly working to alert in the event of a gas leak.
It turns out that in the energetics phases are indicated not by numbers, but by colors (red, green, yellow).
GIS strikes with its monstrousness.
But even more monstrous are transformers with a capacity of 100 megawatts.
Above is a tank with oil cooling the transformer. Oils in the transformer cooling system are 42 tons.
With significant heating, forced cooling is turned on - ten huge fans.
Transformer input contacts. These bare wires have those two hundred twenty thousand volts. Small insulators with "caps" are a short-term overvoltage relief system.
Output busbars with a voltage of 20 kilovolts.
It is surprising that in addition to electronic thermometers and telemetry, such unconventional control methods are used: the camera looks at a hefty mechanical thermometer.
Substation control room.
The racks are computer control systems. All control units are redundant in case of failure.
The dispatcher on duty controls the work of the station. There are five dispatchers in total. Everyone works on a five-day cycle: 12-hour shift from 8 to 20, rest for a day, night shift from 20 to 8, rest for three days. The dispatcher's workplace is also completely redundant in case of equipment failure.
One of the monitors shows a diagram of the substation with connection indication.
There are also fire alarm and video surveillance control systems.
This is how fire alarm electronics look scary.
The second monitor displays the event log. As you can see, everything is in order.
The commandments on the wall.
All doors at the substation are metal. Even the doors to utility rooms are reliably grounded.
A long walkway connects the substation to the new network control center.
In the center there are several control rooms with huge screen walls.
This is the dispatching office of high-voltage networks. Now she manages the operation of nine high-voltage substations, one of which I described above.
On the wall is a diagram of the Moscow power supply.
The second control room will manage the distribution networks (6-20 kV) of Moscow districts. She now operates the Western District networks. I was very surprised that this whole fancy system with large screens serves only for indication. The dispatcher gives all control commands by phone, and the computer system only displays their result.
Several server rooms house computer equipment and communication systems. All power facilities have several redundant communication systems - this is both conventional and IP-telephony, and special dispatching communications and even radio stations in case of failure of all cable systems.
All systems have a backup power supply that works up to six hours plus an automatically starting diesel generator.
It was very interesting for me to visit the substation and control center, I hope you were also interested in my story.
© Alexey Nadyozhin
The main topic of my blog is technology in human life. I write reviews, share experiences, talk about all sorts of interesting things. My second project - lamptest.ru. I test LED bulbs and help figure out which ones are good and which are not so good.