Electric power industry consulting
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
At the ends of the cable line, there are cable terminations. Metallic screens of cables are removed from terminations to the outside, where they are connected in accordance with selected bonding/ grounding scheme. For example, the figure shows the high voltage cable line with one-sided grounding of screens. To have this scheme, metallic screens, with
Designing a cable line is an interesting process that resembles moving in a circle. The fact is that in order to select cables, we need the correct values of the short-circuit current (1.1) and the steady-state current (1.2). Such currents can only be calculated using information about the impedances of the cable line (R1, X1,
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,
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
If the cable is laid not in the ground, but on some structures, then it usually needs to be fixed. This is necessary, for example, so that during the passage of short-circuit currents through the cable, the forces that arise do not move the cable from place to place. A huge number of different versions
There are a huge number of different types of transition towers between cable and overhead lines. The photo shows one of the HV types which is used on the territory of the UK. There are similar examples from around the world. As you can see, the equipment of the transition tower is surrounded by a