Insulation panels are affected by the weather
There are many kinds of insulating sheets, which have been widely used in power system for their excellent insulating properties. Commonly used solid insulating materials are: insulating paint, insulating adhesive; Fiber products; Rubber, plastics and their products; Glass and ceramic products; Mica, asbestos and its products. Both insulating varnish and insulating adhesive are important insulating materials based on polymer, which can be cured into insulating hard film or insulating whole under certain conditions.
Insulation board
Insulating paint is mainly composed of paint, solvent, thinner, filler and so on. After film curing, insulating varnish has high insulation strength. Generally, it can be used as immersion or coating insulation for motors and coils. According to its use, it can be divided into immersion paint, enameled wire paint, finish paint, silicon steel plate paint and anti-halo paint. Insulating glue is similar to insulating paint and is usually filled with filler. It is widely used in casting cable joints, bushings, current transformers 220kV and below and voltage transformers 10kV and below. The insulation adhesive used is yellow cable adhesive, black cable adhesive, epoxy cable adhesive, epoxy resin adhesive, epoxy polyester adhesive and so on.
Insulating fiber products refer to insulating materials made of insulating paper, cardboard, paper tubes and various fiber fabrics. Impregnated fiber products are made from insulating fiber products and impregnated with insulating paint. It has a certain mechanical strength, electrical strength and moisture resistance, but also has some special functions, such as mold resistance, electrical resistance and radiation resistance. Insulating electrical laminates use fibers as substrates, dip coated with different adhesives, and hot-pressed or rolled laminated structural insulation materials. Their properties depend on the substrate, binder and molding process. Can be made with excellent electrical properties, mechanical properties, heat resistance, mold resistance, arc resistance, corona resistance and other characteristics of the product.
Air has good insulating properties. After breakdown, its insulation performance can be recovered immediately and automatically. The electrical and physical properties are stable, the source is extremely rich, and the application is relatively wide. However, the breakdown voltage of air is lower. Electrode sharpness, short distance, steep voltage waveform, high temperature and high humidity can reduce the breakdown voltage of air. Compressed air or vacuum is usually used to improve the breakdown voltage of air.
Insulation panels work outdoors and are directly affected by atmospheric conditions. They are also contaminated by fumes, steam and pulverized coal from mixed traction lines. Dust particles can easily adhere to surfaces and cause insulation leakage. The arc further carbonizes the surface of the insulation plate, and the carbon marks are distributed on the surface of the insulation plate in an irregular tree shape to break the insulation. Therefore, it is required that the manufacturing process of insulation board is strict to ensure the surface smoothness, so that it is difficult to adhere to dirt and has good arc resistance.