Electric power industry consulting
Single-core cables are used in networks of all voltage classes from 6 to 500 kV. Such cables have conductive screens (CU or AL), and these screens are often grounded on both sides. This leads to the appearance of significant longitudinal induced currents (Is) in the screens caused by the 50 Hz magnetic field of the
When any element of the electrical network is energized, a transient process usually occurs. For example, when a voltage is applied to a power transformer, an inrush current of a magnetic nature occurs. The magnitude of the magnetization current of the transformer can reach several kA and sometimes causes serious concern. Today let’s compare inrush
I don’t have an electric car. But I try to keep an eye on the difficulties their customers face. Some of these difficulties are completely unexpected.✅Charging points are stained with birds, and they are unpleasant to use, especially near the ocean or river, where there are a lot of seagulls.✅Charging points sometimes don’t have cables
Sometimes it seems to me that the world has gone crazy. At such moments, I think – God, thank you that I have my specialty “power cables”, which on the one hand allows me to distract myself from sad thoughts, and on the other hand to do something really necessary and useful for society. Apparently,
Cable lines (1 kV and above) are often laid in polymer pipes. In some countries, cable pipes are also referred to as ducts or conduits. These pipes/ducts/conduits allow to:✅Protect the cable from the mechanical damage.✅Protect the cable from the environment.✅Reduce the requirements for the quality of trench bottom preparation.✅Speed up cable pulling and its subsequent
Sometimes it is necessary to have several cables for each phase. For example, this happens when an overhead line (OHL) and a cable line are connected in series (see photos). Or it happens when we connect a transformer of a great power to the busbars (or consumers) using a cable line. Cable connections of overhead
Single-core cables of medium voltage 6-35 kV often have simple grounding of the screens on both sides (“solid bonding”). As a result, the cable screens form closed contours, and the magnetic field of the core current induces currents in these contours, that is screen currents. Induced currents (Is) in the screens pass through the screens
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
Very often we see posts where designers and installers share beautiful photos of successfully completed projects. However, then, quietly, in private correspondence, the exploiting organizations share other photos and accompany them with words “What should we do with this?” or “How do we fix this”? In short, many “successful” projects turn out to be “UNsuccessful”
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