Electric power industry consulting
There are cable lines, there are overhead lines. However, there are also mixed lines consisting of both cable and overhead sections. On such mixed lines, the question arises as to how best to equip a transition point. There are a lot of issues there:➡️ where to place the set of cable terminations and of which
When laying cable lines in the ground, there are several different ways to provide mechanical protection for cables. The following options are known:1️⃣ Covering the cable with bricks on top.2️⃣ Covering the cable with polymer tiles/covers.3️⃣ Laying cable in pipe/duct/conduit.4️⃣ Laying cable in tray/trough.5️⃣ Laying cable in concrete tunnel.Another way of protection is to lay
We often think that 6-35 kV medium-voltage (MV) networks are simpler than 110-500 kV high-voltage (HV) networks. Of course, this is not the case, and it is in MV networks that many serious problems are concentrated – among them, for example, the selection of the optimal method of neutral grounding as well as the selection
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
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
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
In 6-35 kV networks, many methods of neutral grounding are known. They differ in the magnitude of the ground fault current, the magnitude of the voltage increase on two intact phases, the ability to quickly search and selectively disconnect a damaged line, and so on. Let’s discuss a different question – how does the neutral
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,
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
Sometimes I envy overhead line (OHL) specialists because it’s always easy for them to show what they are doing. They walk down the street with family and friends and say – look, there is a tower (pylon, pole), there are wires hanging, and shield wires above them, and birds that have built nests. But what