Analysis on comprehensive fault rate of oil-immersed power transformer based on FTA

Oil - immersed power transformer is one of the most common machines in power grid. Affected by operation environment and the aging of equipment, oil-immersed power transformers often develop faults,which will greatly reduce their lifetime, while with appropriate maintenance, the lifetime can be lengthened. Therefore, the technology of fault diagnosis and maintenance is particularly crucial to the reliability and safety of power transformers.In this paper, the fault tree model of power transformer is established to analyze its comprehensive fault rate corresponding to different bottom events and the calculation method of the comprehensive fault rate is put forward. Through practical application, the validity of the fault tree model and the integrated rate calculation method can be confirmed.