Ultrahigh-voltage oilpaper capacitive bushing capacitor core drying method

Abstract

The invention relates to an ultrahigh-voltage oilpaper capacitive bushing capacitor core drying method comprising the following steps: pre-drying before rolling: a base paper bundle of insulating paper is dried in a drying room, and a small amount of free water in the insulating paper is removed; drying during rolling: the insulating layer is continuously dried layer by layer on a paper path by a baking lamp drying system and an oil heating system when the base paper bundle is in a single-layer state after the base paper bundle is opened and before the base paper bundle is rolled into a core; and drying after rolling: water absorbed by the dried insulating layer in the rolling process is removed by a voltage-transformation vacuum drying process. By adopting the method of the invention, water in the insulation can be removed effectively to enable an ultrahigh-voltage bushing to be low in dielectric loss (<=0.4%), the high-temperature heating time of the whole insulation is short, the mechanical properties of the insulation is ensured, the degree of drying inside the bushing and the degree of drying outside the bushing are consistent, the situation in which water residue exists in the middle of the inner layer of a core is avoided, the insulation can have a longer service life, and water is prevented from diffusing from the inside to the outside after the bushing runs for a period of time.

Description

technical field [0001] The invention relates to a drying technology for bushing capacitor cores, in particular to a drying method for ultra-high voltage oil-paper capacitor type bushing capacitor cores. Background technique [0002] my country's economy is developing at a high speed, and the power load is increasing rapidly. In order to meet the electricity demand in different regions and promote the optimal allocation of energy resources, the voltage level of my country's transmission lines continues to rise. Since 2007, the planning and construction of the million-volt UHV power grid has been started. By 2015, a UHV AC power grid with "three vertical, three horizontal and one ring networks" will be formed. Strong demand. At present, the bushings used in China's UHV power grid are all dependent on imports. my country's lack of UHV bushing production technology restricts the development of my country's domestic UHV bushings and affects the localization of my country's UHV p...

AI Technical Summary

Problems solved by technology

[0005] In view of the shortcomings in the prior art such as long drying time, affecting the service life of insulation and incomplete drying, the technical problem to be solved by the invention is to provide a safe and reliable method for shortening the drying time and solving the problem of insulation transition aging. And the drying method of UHV oil-paper capacitive bushing capacitive core due to incomplete internal drying, which makes the dielectric loss of the product rise.

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