The Breakdown Characteristics of Oil-Paper Insulation in Converter Transformers

Oil-paper insulation is the most widely used insulation material in converter transformers, and its safe and reliable operation is one of the important factors to ensure the normal operation of converter transformers. In the long-term working process, the formation and accumulation of space charge in the oil-paper insulation will affect the oil-paper interfacial characteristics and the internal electric field distribution, and will affect the breakdown characteristics. Therefore, it is of practical significance to conduct in-depth study on the charge transport characteristics and breakdown characteristics and mechanism of oil-paper insulation under the influence of space charge. Based on the study of oil-paper insulation breakdown characteristics, this paper systematically studies the space charge characteristics, oilpaper interface characteristics of oil-paper insulation and its breakdown characteristics in different states. Through this research, according to the breakdown strength of oil-paper insulation under different conditions, it can provide support for the design of UHV converter transformers, provide experimental basis for improving the breakdown field strength of oil-paper insulation, and provide a deeper understanding of the solid-liquid interface characteristics based on theoretical study.