Cable lines - various topics / 20.11.2024

Cable line reactive power

AC 50 Hz cable lines are often referred to as reactive power sources. In idle (no-load) operating mode, any cable line by its capacitance generates reactive power, which creates difficulties:✅ for a network that is forced to consume reactive power;✅ for a cable that is heated by idle currents, especially at the beginning of the

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Cable lines - various topics / 01.11.2024

Three-core cable with sector-shape cores

Previously, oil-soaked paper was used as insulation for medium-voltage cables of 6-20 kV classes. At the same time, there were two core designs – round-shape or sector-shape. The advantages of cables with sector cores (Design 1) are shown on the slide. Currently, cross-linked polyethylene (XLPE) is mainly used as cable insulation. Of course, the question

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Cable lines - various topics / 18.09.2024

Short circuit currents in cable networks

There are two main types of power transmission lines – overhead lines and cable lines. Traditionally, in high-voltage networks, the total length of overhead lines exceeded the total length of cable lines. Therefore, some errors in the calculations of impedances of cable lines were not able to lead to serious consequences. However, gradually, especially with

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Cable lines - various topics / 18.06.2024

High Voltage Cable Lines

The distribution of the book “High Voltage Cable Lines” (dated 2024) has begun: This electronic book, dated 2024, explores the design, construction and operation of alternating current cable lines rated from 6 to 500 kV, consisting of single-core or three-core cables with XLPE insulation. It is intended for employees of design organizations and power grid companies,

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Cable lines - various topics / 24.05.2024

Ribs along the cable outer sheath

There are dozens of cable manufacturers in the World. They are constantly experimenting, trying to offer the market improved cable designs. Some of these innovations are not entirely successful. Unfortunately, these experiments are paid by grid companies, which get troubles during the proccess of laying cables, their operation and repair work. In my opinion, one

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Cable lines - various topics / 29.01.2024

How to catch a cable?

Let me please start a new series of posts about cable lines, scheduled for 2024, with a comic comparison of the cable pulling process with the fishing. This is the real story that happened a couple years ago with 110 kV cable when it was pulled in a hilly city. For that 110 kV cable,

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Cable lines - various topics / 01.06.2023

Bad guys VS cables

We usually think that the core and its XLPE-insulation play the main role in the cable design. At the same time, we perceive the metal screen (Cu, Al) and the outer sheath (PE, PVC, etc) as secondary elements of the cable. It’s a serious mistake. SCREEN. As already shown in previous posts, in normal operation

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