1, What is dielectric strength?
Dielectric strength is a physical quantity used to characterize the electric field strength of insulation materials. In short, it refers to the maximum electric field strength that insulation materials can withstand per unit thickness. Usually expressed in terms of the electric field strength per unit area, in kilovolts per millimeter (kV/mm). The higher the dielectric strength, the greater the impedance of the insulation material, and the smaller its impact on the electric field, resulting in better insulation performance.
2, What is the dielectric strength of transformer oil?
As the insulation medium of transformers, transformer oil needs to consider its dielectric strength. Generally speaking, the dielectric strength of mainstream transformer oil is usually between 50-70 kV/mm. In actual use, in order to ensure its safety and reliability, the dielectric strength is usually set to about half of the electric field strength in oil, that is, the electric field strength in oil is 20-30 kV/mm.
