What Factors Affect the Performance of Insulating Materials?
1. Relative dielectric constant and tangent of dielectric loss Angle
Insulation materials are used for two purposes: electrical network components of mutual insulation and capacitor media (energy storage). The former requires relatively small dielectric constant, the latter requires relatively large dielectric constant, and both require medium loss Angle tangent small, especially in high frequency and high voltage applications of insulating materials, in order to make the medium loss small, require the use of dielectric loss Angle tangent small insulating materials.
2. Insulation resistance and resistivity
Resistance is the reciprocal of conductance, and resistivity is the resistance per unit volume. The less conductive a material is, the greater its resistance is, and the two are inversely related. For insulating materials, it is always desirable that the resistivity should be as high as possible.
3. Breakdown voltage and electrical strength
Under a certain strong electric field, the insulation material is damaged, and the insulation performance is changed into a conductive state, which is called breakdown. The voltage at the time of breakdown is called the breakdown voltage (dielectric strength). Electrical strength is the quotient of the voltage at the time of breakdown under specified conditions and the distance between the two electrodes to withstand the applied voltage, that is, the breakdown voltage per unit thickness. For insulating materials, the higher the breakdown voltage and electrical strength, the better.
4. Tensile strength
Is the maximum tensile stress that the specimen bears in the tensile test. It is the most widely used and representative test for the mechanical properties of insulating materials.
5. Fire resistance
The ability of an insulating material to resist burning when in contact with a flame or to stop it from burning when it leaves the flame. With the increasing application of insulating materials, it becomes more and more important to improve the flammability of insulating materials through various means. The higher the flammability, the better the safety.
6. Arc resistance
The ability of an insulating material to withstand arc action along its surface under specified test conditions. In the test, the arc resistance of the insulating material is judged by the time it takes for the conductive layer to form on the surface of the insulating material due to the arc action generated between the two electrodes by ac high voltage and small current. The higher the time value, the better the arc resistance.
7. Seal
The sealing isolation of oil and water quality is better.