Powerlines

Powerlines are our last theme regarding the electrical grid. Let’s have a quick look through the spider web-like connections between the building blocks of the grid.

Mon Jun 13, 2022

Powerlines

Pictured: Powerline "Vrsech" 400kV (picture may be way too big but eh)

How does it work

Powerlines may look simple, but a fair bit of engineering goes into every single pylon.

Electrical engineers have to establish quite a lot of things before construction of the line starts such as voltage, number of circuits, height of pylons, path and presence of obstacles (rivers, mountains etc).

Pictured: Blueprint for a pylons 330kV.

Powerlines only carry electricity, right ? No, powerlines also carry information about its own status, calls from substation and basicaly everything that can be transmited by wire. This is achived by the so called "High Frequency Connection" HFC for short.

Difference between Powerlines

Different powerlines have different characteristics, but the most important one is voltage. Based on the country or continent, there are standards for the powerline’s working voltage.

For the EU, they are 110kV, 220kV, 400kV. Those are rookie numbers compared to the Eastern connected grid (Russia, Ukraine, Belarus and so on.) The standards there are 110kV, 220kV, 330kV, 500kV, 750kV, 1150kV.

As we can see, the voltage is much higher because the land covered by the giant grid is much more massive

Pictured: Ukrainian workers working on a 750kV powerline.

Now that we have established that powerlines can have different voltages, we have to talk about their location. Powerlines can be either placed overhead or underground. You may be wondering why we have overhead powerlines when we can place them underground. Well that is because insulation is expensive, like really expensive. If it’s an overhead line, we don’t need insulation as the air insulates the powerlines (This can change when it reaches the Break Down Voltage).

Safety

If you plan on visiting a big overhead line remember one thing electricity is antisocial. It doesn’t like it when people get inside its personal space, so it kills everyone who tries to disturb it. You cannot survive no matter what you do, especially with voltage that high (current too). It will turn you into dust, so remember to always maintain 50 meters from the powerlines and leave climbing the pylons to the professionals.

Pictured: Table that shows Horizontal clearance to voltage ratio

Powerlines are the parts of the grid that no one notices, but once we stop to take a look, we realise how amazing the link between power plants and consumers is.

Radi
Subject: Basics of Electricity

Powerlines

Powerlines

How does it work

Difference between Powerlines

Safety

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