Insulation Materials Important Material
Insulation material is one of the most important materials in the transformer, its performance and quality directly affect the reliability of transformer operation and transformer life. Insulation Materials In recent years, the transformer products used in the new insulation material after another.
With the rapid development of science and technology, electrical appliances, transformers and other electrical equipment is increasingly widely used. While the reliability and service life of the transformer is largely dependent on the insulation material it uses. Insulation materials are increasingly engaged in the design and manufacture of transformers.
Insulation material, also known as dielectric, Insulation Materials is a high resistivity, low conductivity of the material. Insulation material can be used to isolate live or different potential of the conductor, so that the current flow in a certain direction. In the transformer products, insulation materials also play a cooling, cooling, support, fixed, arc, improve the potential gradient, moisture, Insulation Materials mildew and protective conductor and so on.
Transformer Insulation material heat resistance grade refers to the insulation material in the transformer to allow the maximum temperature. If the correct use of insulating materials, you can guarantee the material 20 years of service life. Otherwise it will be based on 8 ℃ law (A-class insulation temperature for each rise of 8 ℃, half of life, B-class insulation is 10 ℃, H level is 12 ℃. Insulation Materials This law is known as heat aging 8 ℃ law) Service life. The heat resistance of the insulating material composed of the polymer is lower than that of the inorganic dielectric. The properties of insulating materials are closely related to their molecular composition and molecular structure.
Transformer insulation materials, Insulation Materials many varieties, according to its form can be divided into gas insulation materials, liquid insulation materials and solid insulation materials.
The four basic parameters of the electrical properties of transformer insulation include insulation resistance, dielectric coefficient, dielectric loss factor and dielectric strength.
The concept of insulation resistance Insulation material resistance refers to the insulation material in the role of DC voltage, the pressure is longer, Insulation Materials and the line on the charging current and absorption current disappears, only the leakage current through the resistance value / generally specified as the voltage Plus a minute later, the measured resistance value is the insulation resistance value. For high-voltage large-capacity transformers, the insulation resistance is specified for 10 minutes.
In the course of the operation of electrical equipment due to long-term by a variety of factors, insulation materials, a series of irreversible chemical and physical changes, Insulation Materials resulting in electrical and mechanical properties of deterioration, this irreversible change is often referred to as aging. Insulation aging is divided into heat aging, environmental aging and electrical aging. Factors that cause aging are heat, electricity, light, oxygen, radiation and microbes.
Due to the heat, the aging of the insulating material is called heat aging. In the heat aging process, the polymer insulation material is often thermal degradation, Insulation Materials low molecular weight or escape. So that the insulation properties of insulating materials and mechanical properties decreased.