Experimental Studies on the Low Temperature Performance of Transformer Seals

As one of the main defects in oil-immersed transformer, the oil leakage is always a concern in transformer manufacture and design. The paper addresses the transformer seals via the experimental investigating on low temperature performance considering their material and type. A seal performance testing system and the test method are proposed, whilst an experiment system is built, by which the low temperature performances of five kinds of seals have different filling rate and compression ratio are investigated. The deformation rate and elastic recovery, the selection of seals and structures under extreme cold conditions are investigated. From the long-term low temperature sealing performance tests, conclusions about the material selection and anti-leakage measures for seals in low temperature ambient transformer are proposed.