Overhead Line Fault Indicator To Ensure Safe Operation Of The Distance
1, electrical failure and its prevention.
Overhead Line Fault Indicator Distribution network in the operation often failure, most of the short-circuit fault, a few is broken line failure.
Short circuit refers to the phase or phase or between the ground connection, which includes three-phase short circuit, three-phase short-circuit, two-phase short circuit, two-phase short-circuit ground and single-phase short-circuit ground.
The main reason for the short circuit is the same insulation or relative insulation is damaged, such as insulation breakdown, metal connections, etc.
Short circuit not only in the loop to produce a large short-circuit current, resulting in a large thermal effect and electric effect of the root, thus damaging electrical equipment, and short circuit will cause the power network voltage drop,Overhead Line Fault Indicator near the short-circuit point closer to the voltage drop, The normal power supply
(1) single-phase ground.
Line single-phase point to ground insulation damage, the phase current through this point into the earth, called single-phase ground. Single-phase grounding is the most common opportunity in the electrical fault. Its main hazard lies in the destruction of the three-phase balance system. The voltage of the non-fault phase can cause the failure of the non-fault phase insulation, Three-phase short-circuit ground.
There are many factors that cause single-phase grounding, such as the disconnection of a phase wire, the twist and the wire, the jumper due to the discharge of the pole against the tower,Overhead Line Fault Indicator the insulator of the support or fixed wire, the insulation breakdown of the arrester.
(2) two-phase short circuit.
Line between any two phases caused by direct discharge called two-phase short circuit, will make the current through the wire than the normal increase in many times, and in the discharge point to form a strong arc, burn the wire, resulting in interruption of power supply.
Two-phase short-circuit, including two-phase short-circuit ground, than the single-phase ground situation is much more serious.
Two-phase short circuit for the reasons: mixed, lightning, external damage and so on.
(3) three-phase short circuit. In the same place in the line three-phase direct discharge called three-phase short circuit.
Three-phase short-circuit (including three-phase short-circuit grounding) is the line of the most serious electrical failure, but it appears less chance.
Three-phase short circuit of the reasons are: mixed line, line with ground line, the line caused by three-phase inverted bar and so on.
2, lack of phase.
Disconnection is not ground, usually also known as the lack of phase operation, will make the three-phase voltage transmission side, the receiving side of a phase without current,Overhead Line Fault Indicator three-phase motor can not run. Resulting in the reasons for the lack of operation is: fuse a phase of the burning, the tower of a phase jumper due to bad joints or blown.
3, the prevention of electrical failure.
Depending on the cause of the electrical failure, the following precautions may be taken:
(1) single-phase ground:
Timely clean up the line corridor, felling of high trees,Overhead Line Fault Indicator the demolition of dangerous construction of dangerous construction, to ensure the safe operation of the distance;
(2) mixed line:
Adjust the sag, expand the distance between the distance, narrow range;
(3) external damage:
Suspension of safety warning signs, to strengthen the publicity of the pole protection line, to strengthen the abnormal changes in the grade line corridor;
(4) Lightning prevention:
Install the arrester, reduce the grounding resistance, reduce the degree of damage to the lightning; enable reclosing function, improve power supply reliability;
(5) Insulator breakdown:
Selection of qualified insulators, to meet the insulation with the conditions to improve the voltage level and anti-pollution level; to strengthen the absolute sperm cleaning.