Inter-phase short circuit of 10kv overhead lines during strong winds
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In our company’s 10KV overhead lines, the spacing between the 8 bare conductors on one crossarm is within the specified standards; however, the span between poles is 40 meters, and the sag is a bit excessive. During strong winds, the conductors sway back and forth, resulting in short circuits. I would like to ask the experts here for any methods you might have. Prevent the wire from swinging.
This post was last edited by liuei on 2011-4-18 21:23; it should be fixed using those lightweight composite insulators
Fix it in the middle of the line; you can also choose several locations.
It can be secured near the point where the wire sags using that lightweight insulating material. The original poster might want to go to a place by the sea with strong winds to see it; high-voltage power lines all have this kind of material installed on them
In mountainous areas with frequent storms, high-voltage and extra-high-voltage lines use LGJ-type expanded-core aluminum conductor wires or LG-type aluminum-steel expanded hollow conductors in place of double-split conductors; or gap rods are installed on the split conductors to prevent the conductors from swinging into contact with each other. The greater the wind speed, the larger the span, and the lighter the conductors, the greater the amplitude of wind-induced sway. When the upper and lower conductors of a double-split conductor sway out of sync, the two conductors can come very close to each other or even touch; adhesion occurs when the load current is high enough. The electromagnetic attraction between the sub-wires weakens the tendency of the upper sub-wire to swing away from the lower sub-wire, while strengthening the tendency of the lower sub-wire to swing towards the upper sub-wire. Double-split conductors located at windward areas, with large span distances and high loads, have a higher probability of sticking together. If, due to reasons related to installation or repeated wind movements, the lower conductors shift outward along the suspension clamps, resulting in a distance between them of less than 400 mm, or when the span distance is very large, the probability of sticking together increases further
There are clamps on the lines nowadays; you can connect a few more of them, which is the most cost-effective option
There are several ways to address this issue, and they are now commonly used in lines with a voltage of 220 KV or higher. 1) Install composite insulators between phases, which are those that are directly fixed to the lines. 2) Increase the spacing between utility poles. The former is the most widely used nowadays