Failures statistics of on-line monitoring devices for gases dissolved in oil

Abstract

The on-line monitoring device of dissolved gas in oil is an important starting point to understand the internal operation condition of large oil filled equipment such as transformer. However, the device has no unified maintenance strategy. At present, it basically adopts the strategy of “repair only when it is broken”, which seriously affects the real-time perception ability of the device to the health state of primary equipment. According to the components of the device, the device faults were divided into four categories: Status information access controller (CAC) fault, carrier gas fault, communication fault and monitoring device body fault. In addition, they were subdivided into eight secondary faults according to the detection principle and process. Through the big data analysis of the operation and maintenance records of a province in recent three years, it was found that the main causes of the device faults were the under voltage of the carrier gas and the fault of the monitoring device body. It was suggested to popularize the device using carrier gas maintenance free type or photoacoustic spectrum principle to reduce the frequency of device failure. At the same time, it was suggested that the device design should be transformed to modularization to facilitate the fault operation and maintenance of the device body. The degassing module and intelligent monitoring module of the unit should be focused when formulating the maintenance strategy of the unit in the future.