Internal Pressure Change Characteristics of Oil-impregnated Paper Bushing Based on Electro-thermal Coupling
The oil-impregnated paper(OIP)bushing is currently the most widely used bushing type in power systems and its internal defects can not be timely found due to the unknown dynamic pressure during operation,which seriously im-pairs the service life of the bushing.Therefore,an analytical mathematical algorithm for the internal pressure of the OIP bushing is proposed in the paper.Then,an electro-thermal coupling model of the testing OIP bushing is established to an-alyze the influence of the conductive rod current and ambient temperature on the internal pressure.Moreover,the testing OIP bushing platform is used to verify the accuracy of the algorithm.The results show that the mathematical model of the bushing has high computational accuracy,and the air pressure inside the breathing chamber is the main factor affecting the internal pressure changes of the bushing.Combined with the analyses of the simulation,the air pressure accounts for 76.9%of the internal pressure of the bushing.The research results have important guiding significance for mastering the internal pressure distribution of OIP bushing and timely capturing abnormal states of OIP bushing.
electro-thermal couplingoil-impregnated paperbushinginternal pressuremathematical model