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We have all experienced power outages; accidents, alas, do happen. The time required to restore power is always important, because in addition to the potential losses of millions of dollars to the industry, prolonged power outages will also have social consequences, especially in homes, schools, hospitals, and other important facilities. Influence. This becomes particularly dangerous in winter.

The longest power outages were caused by tower collapse accidents caused by natural disasters: Lei Feng, tornadoes, hurricanes, etc. The urgent need to shorten the time to eliminate the consequences has led to the development of various types of rapid installation tower overhead lines all over the world.

Our company's experts did not stand by. Our company operates in sparsely populated and inaccessible swamp areas, where the quality and quantity of road infrastructure are not satisfactory. In this case, we must develop a temporary tower that allows us to install it on site without using crane structures on site. Such towers must be light, durable, resistant to natural and climatic factors, and do not require special foundations. The above quality is especially suitable for our company in summer and autumn. At that time, it was almost impossible to deliver and install steel towers or reinforced concrete towers at the accident site (work in permafrost areas can only be carried out in winter, after which the ground freezes. snow).

The development and calculation work with experts from Novosibirsk began in 2014. The partners provided different versions for their consideration. Our company’s experts chose a pyramid structure version with polymer insulators, composed of pillars and made of composite materials.

The base of the proposed support tower is made into a triangle and can be installed on the ground without using a foundation (Figure 1). In the upper part of the structure, there is a cross-section of the vertical pillars, and the transmission line wires are connected to the vertical pillars using polymer insulators. The two sides of the pyramid are composed of two X-shaped intersecting pillars, and the third pillar is the pillar supporting the main pillar.

The calculations performed include static calculations, determination of the forces between the internal elements of the supporting tower, and verification of the strength, stability and flexibility of the tower elements. A prototype was made and field tested (Figure 2), which shows that improvements are needed. In order to facilitate the personnel supporting the tower, special step bolts were made and installed on the tower body, safety ropes were installed, and many other items were added.

The experimental test proved the applicability of the operation and the correctness of the calculations, and in the process proved the ability to install the tower without lifting machinery. In order to reduce the installation and disassembly time of the support tower, two turnbuckles are installed at the connection node in the middle of each bracket, and a hinge knot is installed on the bracket to prevent breakage during installation on uneven surfaces.

The result of the work is a carefully designed and tested tower with the following functions: installation by a team of eight people in 8 to 10 hours, and then installation of the wires, which takes two to three hours. The structure weighs approximately 5,500 pounds, and its overall dimensions in the transport position are 6.6 feet x 3.3 feet x 33 feet. The lifting of the X-shaped cross brace requires a 2-ton traction mechanism (light all-terrain vehicle, manned truck). Once the traditional tower is installed, the temporary tower can be disassembled and transported to a storage location for reuse.

The first case of practical application of temporary towers soon appeared. In the power grid of our branch, it was found that Tower 116 of the 35 kV Komsomolskaya-Severny Kupol line was damaged. Due to the influence of frost heave on the foundation and uneven extrusion of foundation piles from the ground, an emergency slope is generated. When spring comes, the tower may collapse due to melting soil or the influence of wind. To prevent this, we decided to install a new composite tower.

A staff of six installed the tower within eight hours, and within six hours removed the wires from the emergency tower and installed them on the temporary tower. Of course, the tower was installed in winter (Figure 3), because in summer, it takes longer to work in such swampy areas. As a result, the temporary tower remained in place for about two months, and no problems were found.

Later, our organization had experience in using helicopters to transport the assembled tower to the accident site. The assembled tower is installed on the overhead line by helicopter, which saves time and reduces the labor intensity of personnel. Work at the accident site was reduced to releasing electrical wires from the fallen tower and installing them on temporary towers.

The advantages of quick installation towers designed to eliminate accidents include no need for foundations, fast transportation to remote areas, the possibility of multiple uses, and suitable installation on soils (swamps) with weak carrying capacity. Later, this design was patented.

In short, this work is challenging, but very necessary, and done in a responsible manner. We have developed a convenient tool to eliminate the consequences of overhead line accidents, which are now used not only in our organization, but also by many other organizations. This innovation is actively spreading throughout the country's power system, making this idea and its implementation on a truly national scale. This development may also arouse the interest of the global power industry, especially in areas located in permafrost areas-mainly Alaska and Canada, as well as locations of systemic natural disasters, especially the entire tornado alley in the United States and hurricane-prone Florida. And other states on the Gulf Coast.

—Konstantin Ivanov is the Deputy CEO of Development of JSC Rosseti Tumen. He holds a master of science degree in electrical engineering, is a well-known engineer and manager in the Russian power industry, and has nearly 20 years of experience in this field.

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