Direct current deicing method of extra-high voltage ground wires

Abstract

The invention discloses a direct current deicing method of extra-high voltage ground wires, comprising following steps: carrying out semi-insulating modification to to-be-deiced region ground wires: connecting the to-be-deiced ground wires and a lead wire; connecting a direct current deicing device and the lead wire; starting the direct current deicing device to deice the ice covered ground wires in the region; after the covering ice on the ground wires in the region falls off completely, disconnecting and removing the direct current deicing device, thus finishing deicing the ground wires. According to the direct current deicing method of the invention, the semi-insulating modification is carried out to a target deicing line; the extra-high voltage ground wires are kept insulated from an iron tower in deicing; the insulation bridge connection problem in serious ice coverage is effectively avoided; the function of overvoltage protection of the ground wires is kept; according to the invention, modification is carried out for only once in the deicing processing; any other operation is unnecessary; the semi-insulating modification facility is unnecessarily removed after finishing the deicing job; the deicing operation of the next time is convenient; the cost is very low; the deicing workload is greatly reduced; and the deicing efficiency is improved.

Description

technical field [0001] The invention belongs to the technical field of electrical functions, and in particular relates to a DC ice-melting method for extra-high voltage ground wires. Background technique [0002] With the development of my country's electric power industry, the UHV power grid is gradually developing into the backbone grid of the entire power grid, and its transmission reliability is particularly important. However, UHV lines have long transmission distances and complex climate conditions in the areas they pass, which can easily cause severe icing. Because there is no load current in the overhead ground wire of the UHV line, its ice thickness will far exceed that of the overhead wire, which can easily cause accidents such as ground wire breakage, tower collapse or excessive sag wire discharge to the ground wire, which seriously affects the UHV power grid. Safe and stable operation. [0003] At present, the most economical and effective way to reduce the icing ...

AI Technical Summary

Problems solved by technology

[0002] With the development of my country's electric power industry, the UHV power grid is gradually developing into the backbone grid of the entire power grid, and its transmission reliability is particularly important. However, UHV lines have long transmission distances and complex climate conditions in the areas they pass, which can easily cause severe icing. Because there is no load current in the overhead ground wire of the UHV line, its ice thickness will far exceed that of the overhead wire, which can easily cause accidents such as ground wire breakage, tower collapse or excessive sag wire discharge to the ground wire, which seriously affects the UHV power grid. safe and stable operation

[0003] At present, the most economical and effective way to reduce the icing loss of transmission lines is to carry out current melting ice on transmission lines; the ground wire has a large inductance, and DC ice melting is generally used, while the ground wire of UHV transmission lines is generally directly connected to the ground , the ice-melting current cannot be directly applied to the overhead ground wire

In the existing ground wire ice-melting technology, two ground wires are generally connected in series to melt ice, and the UHV ground wire is long and has a large resistance. The general ice-melting device cannot meet the ice-melting capacity requirements

Moreover, in some existing ground wire melting methods, the discharge gap is used to fully insulate the overhead ground wire, but when the ice is seriously covered, the discharge gap may also be bridged due to ice coating, and the overhead ground wire is still grounded, which cannot be implemented. Melt ice; and carry out full insulation transformation on the line (specific transformation such as figure 1 As shown), it is time-consuming and labor-intensive to dismantle and transform the facilities after the ice melting is completed; if multiple ice melting is required, the transformation and removal of the line will take a lot of time and work energy

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