Introduction to organic silicone electrical insula...

Introduction to organic silicone electrical insulating medium         Silicone electrical properties than general insulating oil is good, but its wide viscosity range, good thermal stability, oxidation resistance, small dielectric loss, solidification and vapor pressure low, lightning and high flash point, keep good dielectric properties in the temperature and wide frequency range. But with other insulating material with good biocompatibility, which widely used in all kinds of transformers, capacitors, electronic equipment, parts and components, cable connection position of insulating and cooling, lubricating, damping, impregnating, coating and carrier.        In the most commonly used in transformer oil, mineral oil, the utility model has the advantages of good dielectric properties and low cost, fatal weakness is easy to burn, is not safe; the fire of PCBs is excellent, but there is a strong carcinogen, countries have been banned; HCFC fire is good, but the low boiling point, seal lax is caused by environmental pollution. Compared to silicone oil shows many advantages. So the silicone oil as insulating medium transformer cooling with the development of society and rapid development. In 1972 the United States company will first silicone oil for transformer; in 1974 the first small power transformers available; by 1986 that is more than 30000 units put into use. From 1974 to 1980, accumulative running 300000 hours of operation, rate of only 0.08% damage, but no one from the silicone oil. Conversely, during non damage silicone transformer ratio is as high as 0.2% to 0.4%. At present, the United States, Japan, Europe and Middle East countries, have been using silicone transformer in key sectors of high-rise buildings, residential areas, schools, factories and the special requirements of. In 80, China has also developed a transformer oil, made from the transformer has been operating for many years in the Beijing metro safety department. Although the price is higher than that of mineral oil, organic silicone oil. But with the compact design of transformer, can greatly reduce the oil loading, thus greatly reducing the production cost of the transformer oil. If considering the security and stability of other ancillary facilities and silicone oil, in the long run is economically reasonable. Insulation oil transformer, need cooling, so the viscosity is not easy too high, viscosity 50mm ² two methyl silicone oil as insulating medium has a transformer cooling and better performance. Lightning and burning oil is much higher than mineral oil, combustion heat than mineral oil is much lower, the combustion speed is much slower. In the equilibrium conditions, dissolved water in oil in higher in polychlorinated biphenyls and mineral oil. But under dehydration conditions, from the analysis of oil in water speed is much faster. For example, silicone oil in 75% relative humidity conditions, 24 hours after the moisture content is up to 160 μ l/L, close to its saturation point; when the vacuum dewatering treatment at 45 ℃ for 15 hours, the moisture content can be restored to 20 μ l/L. Insulating oil water content increased, will lead to the decrease of breakdown voltage. The silicone oil to prevent in packaging, storage and transportation process of moisture into the. Once the water more than 100 μ l/L content, i.e. vacuum drying proce. Power capacitor is widely used in no power compensation of the electric power industry, to improve the quality of power supply and utilization of great economy energy. Past use of PCBs do soaked with oil, not only harms the health, and the comprehensive performance is poor, the high cost of repair. Since 70 time, China began to use methyl phenyl silicone oil (250-30) instead of PCBs for power capacitor impregnating oil, has received the good effect, the utility model has the advantages of low expansion coefficient, non-toxic and tasteless, chemically inert, easily compatible with other materials; high voltage can be extinguished local discharge at high pressure, hydrogen absorption of plant, compared with the power capacitor using mineral oil, single capacity can be increased by 2.75 to 5 times, the power loss is reduced by 50%. In the same capacity conditions, capacitor size reduction, infrastructure costs; high working temperature, large overload capacity, long-term safe operation. Silicone oil used as a small power capacitor impregnating oil, also has high stability, can effectively improve the service life. In addition, the cable terminal, connecting box, electrical and electronic equipment components, transistor, magnetron, damp proof insulation cooling lubrication, thermal heat, there are also many applications.