Company Name: Henan Xinchaoda Cable Co., Ltd.
Contact: Manager Guo
Address: Xibaishui Village, Xitao Town, Wuzhi County
Marketing Center: 1812, Building B, Building 3, Shenglong Plaza, Zhengdong New District, Zhengzhou
The overhead line is an important transmission and distribution link. Whether its operation fluctuates is an important factor that affects the safety of the entire transmission and distribution network. As long as the overhead line guarantees fluctuations, the reliability of the power supply line can be added. Under the influence of internal non-fluctuation factors, overhead lines are easily affected in the internally exposed environment, which causes frequent problems.
By analyzing the characteristics of rare faults in overhead lines, and comprehensive analysis of the causes and preventive measures, the quality of operation and maintenance of overhead lines can be further improved.
I. Summary of rare faults in overhead lines
(A) single-phase ground fault
(Two) short-circuit problems
(Three) disconnection problems
Analysis of the causes of rare problems in overhead lines
(I) Analysis of the causes of single-phase ground faults
1. Passages and line elements, passages, and connecting lines are easily accessible to trees, especially in light winds and thunderstorms, and it is easier to connect overhead lines in the suburbs, so once they come into contact with branches, it is easy to cause single-phase grounding problems.
2. Bird damage factors, many birds choose to build nests on the crossbars of overhead lines. Once they encounter rain and snow, it will cause single-phase grounding problems.
3. The impact of overloading factors is also a cause of concern. In winter, the peak power consumption season is often presented. The ends of many circuit wires are easily burned out due to aging, forming a single-phase grounding fault.
(B) analysis of the causes of short circuit
1. The influence of foreign objects is mainly caused by short-circuit problems caused by the dregs in the air around the overhead lines hanging on the lines.
2. The natural elements of lightning. As a few of the cities that have been built have great lightning protection measures, the city has a great short circuit caused by lightning on overhead lines. However, in many central suburbs, the overhead lines are in an open environment, so the occurrence of lightning will cause a sudden increase in voltage, which can easily cause air insulation and lightning breakdown of overhead lines, which will cause short-circuits.
3. Bird damage factors, when single-phase ground faults occur, it is easy to cause problems due to bird nesting. Not only that, birds often get used to staying on overhead lines. If the branches are connected between the two lines, two Internal connecting conductors between lines can easily cause short-circuits between phases.
4.Equipment elements, the line itself will also cause the insulation function of the connection to decrease due to the excessively large arc sag, which may continue the work, which will further lead to the occurrence of short circuit faults.
(Three) analysis of the cause of the fault
1. External force factors, overhead lines can easily cause overhead lines to be disconnected due to vehicle collisions and unexpected damage to construction.
2. Lightning elements: In the process of lightning strikes, bare wires and insulated wires are likely to cause a small amount of heat to occur. Under this action, it is easy to cause the wires to automatically fuse, which will cause disconnection problems. If it is an insulated wire, it is easy to cause a flashover between two and three phases of different wires and lines during the process of electric shock caused by lightning. In addition, the arc will be affected by the magnetic force of the power supply and the thermal effect of electricity. When a negative charge transfer occurs, the concentrated area of the arc can be easily extinguished, causing the wire to break.
3. Preventive measures for rare problems in overhead lines
1. During the active period, stop the cleaning of the connecting line of the line to avoid debris caused by the connection.
2. Stop precautions against damage to external forces, and set up safety reminders at locations prone to vehicle impact. When construction stops around the line, contact the construction unit in time to enhance line monitoring. At the same time, a police-enterprise combination management system should be established to combat the theft of line equipment. Further strengthen the publicity of power equipment maintenance and add awareness of power equipment maintenance.
3. Lightning protection measures. The occurrence of lightning will cause a sudden increase in voltage, and it is easy to cause lightning breakdown of the air insulation of overhead lines, which will cause short-circuits. Lightning rods and oxidation arresters should be installed in a timely manner.
4. Timely introspection and recording of the grounded resistance stop, to ensure that the safety monitoring of electric roads is in place. Set up anti-bird installations to enhance inspection and detection during the current period.