Overhead lines and reactors / 15.01.2024

Breaker vs Reactor (part 1)

The photo shows a 500 kV SF6 circuit breaker (B1), which was damaged during the energizing of the 500 kV overhead line. The cause of the accident was the presence of a 500 kV shunt reactor (SR) on the line, which compensated about 100% of the capacitive reactive power of the line. Let’s look at exactly

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Various energy topics / 05.01.2024

Call me via fiber-optic (if it still works)

For relay protection and grid automatization, adjacent switchgears must exchange the necessary information with each other. Previously, communication was organized primarily through phase wires of an overhead line due to the high-frequency signals superimposed on currents and voltages of industrial frequency 50 Hz. In recent years, the situation has changed, and fiber-optic connections have become

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Cable lines in ducts / 26.12.2023

Bad cable protection on the ground level

The photos show the exit point of the high voltage single-core cable from the ground near the cable ternination. Please note that the cable is placed in a black single-layer corrugated pipe. What’s wrong here? 1️⃣ Corrugated pipe is not a reliable mechanical protection for high-voltage cable. For example, pay attention to the deep cuts

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Cable lines / 25.12.2023

Dear Santa, bring an aperiodic component back!

High-voltage cables must have a conductive metal screen (sheath). The selection of the screen cross-section is very important. Without selecting the screen cross-section (and bonding/grounding scheme), it is impossible:✅ To ensure the resistance of the cable screen to fault (short-circuit) currents.✅ To perform a thermal calculation of the cable line and select the core cross-section.

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Cable lines / 20.12.2023

How do they provide such angles?

High voltage cable terminations are usually installed vertically. This allows you:✅ To ensure the absence of mechanical influences bending the termination under its own weight and the weight of the cable.✅ To ensure high-quality filling of the termination with dielectric oil (not relevant for terminations of dry-type or gas-type). However, sometimes, for various reasons, the

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Various energy topics / 07.12.2023

Electricity for every creature

Birds build nests on the overhead line towers (pylons, poles). Rats feed on the outer sheath of cable lines. Fungus settles on polymer insulators (Photo). What’s next? The photo shows the 110 kV disconnector support insulators installed in Karelia (a region on the southern border of Finland). During operation, it was noticed that over time,

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Overhead lines and reactors / 07.12.2023

Line tower plays football

This is an amazing tower of a 110 kV multi-circuit overhead transmission line. It was built in the Kaliningrad region, former USSR. Although I love electric cables and lead a Linkedin group on them, I still have to admit that it is difficult to make something so bright and attractive out of a cable buried

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