It is hard to imagine everyday life without electricity: it enables normal functioning in many areas, from industry to home devices. In this context, cables in overhead power lines are a key element of infrastructure that allows electricity to be transmitted over long distances. Their design, properties and how to operate have a huge impact on the reliability and efficiency of the entire power system. In this article, we will take a closer look at overhead cables, analyzing their various types, construction, properties and development prospects to better understand the role they play in today's power systems.
Types of cables used for overhead lines
In overhead lines, various types of cables are used, each of which plays a specific role in ensuring reliable electricity transmission. For their assembly, various elements of the equipment are also necessary, such as cable or individually matching matrices and heads.
The basic parts of the overhead line include the working cord, which is the main transmission channel of energy. It can occur as a single cable or as a beam of wires, which increases its load capacity. An important aspect is the fact that the protective and neutral cord is also considered a work cord, which emphasizes its importance in ensuring stability and line safety.
Another important type is the phase cable, which is closely related to the specific phase of the transmission system. This is a key element in sending phase current to receivers, ensuring effective distribution of electricity.
To protect the work cables against possible falling, protective cables are used. They are additional wires that are designed to maintain the working cord in the right position, minimizing the risk of damage or failure. Protection against damage is implemented at every stage - already when laying, equipment such as equipment asdrum stand.
In the case of protection against atmospheric discharge, lightning protection cables play a key role. They are strictly grounded, which enables effective energy discharge from atmospheric display, preventing damage or destruction of working cables. In addition, there are other types of wires, such as grounding cables, which combine elements that require grounding with earth electrode or grounded columns. Another type is shielding cables used to reduce the intensity of the electric field, which is especially important in areas with high building density or in the case of overhead lines passing close to telecommunications facilities or other devices. All these types of cables jointly create a comprehensive system that not only enables effective transmission of electricity, but also ensures the safety and reliability of overhead lines.
Work cables in overhead lines
Working cables are an important element in the structure of overhead lines, playing a key role in sending electricity over the right distances. They can take various forms, including wires, links or links with a load -bearing core, depending on the design specifications and technical requirements. Currently used lightning cables are often made as steel links, which can additionally contain integrated fiber or be covered with a layer of aluminum. Technical standards do not specify the exact parameters of these cables, but they recommend that the diameter of the wires in the outer layer for aluminum cables with a cross -section greater than 50 mm² is not less than 2.33 mm. Requirements for materials and product specification must be agreed between the buyer and the supplier, in accordance with the project and industry standards. The key aspect is the fulfillment of physical and mechanical characteristics, such as linear elongation coefficient or permissible stress of cable materials to ensure the reliability and durability of the entire overhead line. Norms must also be met by additional equipment, such as matrices Afl.
Characteristics of steel-aluminum cables
Steel-aluminum cables are a popular option in the construction of overhead lines, characterized by favorable mechanical and electrical properties. As a rule, they consist of aluminum wires, whose aluminum content is about 99.5%, and a core made of wire or galvanized steel wires, available in different classes (S1, S2 or S3). The cable core class affects its tensile strength and its thermal expansion, which is important when calculating wire overhangs. Aluminum wires twisted around the core can form a single or several layers of outer cable. An important structural detail is to twist the neighboring layers in opposite directions, ensuring stability and mechanical balance of the cable. Thanks to this design, steel-aluminum cables offer a balanced combination of mechanical strength and electrical conductivity, which makes them a popular choice in the energy industry.
To sum up, wires in overhead lines are a key element of energy infrastructure, enabling effective energy transmission over appropriate distances. There are many types of wires, each designed to perform specific functions, such as electricity transmission, protection against atmospheric reliefs or ensuring structural stability.
