What is R-type transformer insulation?

With the rapid development of science and technology, the application of electrical equipment such as motors and power transformers is becoming more and more extensive, but the reliability and service life of electronic transformers depend to a large extent on insulating materials. We also call insulating materials dielectrics, which can be used to isolate conductors with charge or different potentials and make the current flow in a certain direction. In R-type electronic transformer products, insulating materials also play the role of heat dissipation, cooling, support, fixation, arc extinguishing, improving potential gradient, moisture-proof, mildew-proof, and protecting conductors.

The insulation of the transformer mainly includes the longitudinal insulation of each winding, the main insulation between the two windings, the insulation of the high-voltage winding, the insulation of the output terminal, etc. Among them, the longitudinal insulation of the transformer includes turn-to-turn insulation, layer-to-layer insulation and segment-to-segment insulation. The longitudinal insulation needs to consider the various voltages acting on the longitudinal insulation and their gradient distribution, the interaction between the transformer windings and the windings under special circumstances, the influence of the longitudinal insulation on the main insulation, the influence of the segment gap size on the heat dissipation, etc. The main insulation includes: insulation around the ground, insulation between different phase windings, insulation between different voltage levels, etc.

What happens when our electrical insulation fails?

When current passes through insulation, it generates heat, degrading the insulation until it eventually fails, creating a risk of fire hazard. When insulation fails, leakage current must return to the source, through any available conductors, conduits, pipes, water or ground, and this adverse current can generate dangerous voltages. Leakage current can also trip overcurrent protection devices, causing motors and transformers to overheat.

The insulation condition and safe operation level of the transformer directly affect the reliability of the entire power supply system. It is usually necessary to measure and check the insulation between the transformer coils and coils. In fact, it is to check the voltage resistance and insulation of the transformer coils under high working voltage. If the insulation resistance between the coil cores is too low, the insulation is poor or there is a serious leakage fault. At this time, we need to replace or repair it to avoid danger. Generally speaking, the transformer will undergo a handover test when it leaves the factory to prove that the insulation is good. If it is well maintained in daily operation, the insulation will not be damaged, but if the transformer is affected by the environment or abnormal operation, even the best quality transformer may be damaged.