Статья посвящена выбору конструкций и разработке требований к новым линейным изоляторам для распределительных сетей 6-10-20 кВ, обеспечивающих высокую устойчивость воздушных сетей к грозовым перенапряжениям
при прямых и индуцированных воздействиях молнии. Повышение грозостойкости изоляторов позволит сократить
перерывы в электроснабжении потребителей и уменьшить электротравматизм персонала электрических сетей при
восстановительных работах
Стаття присвячена вибору конструкцій і розробці вимог до нових лінійних ізоляторів для розподільчих мереж 6-10-20 кВ,
що забезпечують високу стійкість повітряних мереж до грозових перенапруг при прямих і індукованих впливах блискавки. Підвищення грозостойкості ізоляторів дозволить скоротити перерви в електропостачанні споживачів і зменшити травматизм персоналу електричних мереж при відновлювальних роботах
Introduction. In Ukraine high voltage overhead distribution
lines (OL) of class 6 and 10 kV are the most extended. Their
total length exceeds 280,000 km. More than 95% of the lines
are made on line supports from reinforced concrete racks. On
all poles of the overhead line, pin insulators are installed.
According to the data of operation experience, up to 60-70%
of single-phase earth (SPE) faults due to «insulation» occurs
on VL supports due to damage to line pin insulators, mainly
during the thunderstorm period. Problem. Insufficient reliability of pin insulators leads to interruptions in power supply,
accidents on the line, accidents in the area of reinforced concrete poles, where in the case of insulator damages, a long
process of SPE occurs. Goal. The purpose of the work is to
select the design and develop requirements for new linear
insulators of 10-20 kV overhead lines that provide high resistance to lightning overvoltages with direct and inductive effects of lightning. Methodology. The research methodology
consists in analyzing operational experience, calculating insulator parameters and laboratory tests. Results. Using statistical data on lightning parameters and data on mechanical
loads on insulators, the main dimensions of line post insulators have been determined that will ensure their reliable operation under conditions of intense thunderstorm activity and
extreme ice and wind loads. Conclusions. The main technical
requirements for line post insulators for 10-20 kV distribution
lines were formulated. On the 10 kV OL located in areas with
increased thunderstorm activity it is recommended to use line
post insulators instead of pin-type ones. On the OL-20 kV it is
recommended to use only line post insulators. The use of highlightning-resistant line post insulators on OL-10-20 kV will
significantly increase the electrical safety and reliability of
power supply to consumers. Increased by 2-3 times the cost of
line post insulators in comparison with those used will be compensated for by the effects of reducing the number of collapsible supports, damage from under-supply of electricity, labor
costs during transportation and restoration of destroyed supports, the moral side of reducing accidents in case of electric
shock in the emergency zone. The insulators offered for OL10-20 kV can be used for fixing both bare and protected wires.
The exclusion from the design of the weakest elements – polyethylene caps and metal pins will increase the reliability of the
power isolation unit.
