Analyze common malfunction types of commonly used 1kv AAC ABC cable, 10 kV overhead lines, and 15kv ABC cable to improve power supply reliability.
(1) It is necessary to strictly control the construction, pay attention to the tension of the wire, and make the three-phase wire have the same degree of relaxation and within the specified standard range.
When the line is inspected, the above problems should be dealt with in a timely manner.
(2) When a super-high car is operated under the line or under the line by a crane, it may cause a short circuit or a wire break. Therefore, there should be a certain separation distance on the intersecting and crossing lines.
(3) The wire is damaged by oxidation due to long-term corrosion by moisture, atmosphere, and harmful gases.
The steel wire and lightning conductor are most likely to be rusted. When the wire is found to be seriously corroded during the inspection, it should be replaced in time.
(1) The porcelain insulator on the line is polluted by harmful components in the air, which makes the porcelain part dirty.
In the case of wet weather, the dirt layer absorbs water, which enhances the conductivity, which not only increases the power loss but also easily causes a flashover.
(2) A failed porcelain insulator is mistakenly installed on the line or due to aging of the insulator, flashover breakdown occurs under the action of the power frequency voltage.
In this case, porcelain insulators with flash marks on the inspection should be replaced in time, and the replacement of new porcelain insulators must pass the withstand voltage test.
(3) The porcelain insulation part is damaged by an external force, crack or damage occurs, and when a large porcelain skirt is broken or there is a crack from the edge to the top, it should be replaced, otherwise, the insulation will be reduced and a flashover accident will occur.