The Research About The Transformer Substation Capacitive Equipment’s On-line Monitoring And Fault Analysis

High-voltage capacitive equipment is an important part of the power system. It is mainly consist of High-voltage capacitive casing, current transformer, capacitor voltage transformer, coupling capacitor, etc. Their reliability directly affects the safety of the power grid operation. The online capacity equipments can be used to monitor the status of equipment at any time, and provide evidence for the status evaluation and maintenance decision. But in the meantime, questions also be raised that if the reliability of online monitoring and accuracy of test be guaranteed, and whether the capacity equipments be disturbed and results in misinformation? What method can eliminate interference? These factors will affect maintainer’s judgment on the equipment operation status and the online monitoring system’s application in the fault analysis.This paper carries out research on the above mentioned issue. Firstly this paper elaborates the background and significance of the on-line monitoring of electrical equipment. Through accessing to some information, this paper has an insight into domestic and overseas research status on the online monitoring of electrical equipment and problems existing in practice. Then, in terms of structure of online monitoring device of capacitive equipment of substation, this paper introduces the composition and function of the online monitoring system which is now in service in Fuzhou area, reveals the advantage and disadvantage of this system in terms of voltage monitoring unit, Monitoring unit of the capacity equipment, Monitoring unit of the line side capacity equipment, environmental monitoring unit, understand the structure and using method of OMDS system. Then, this paper analyzes factors in the system which may influence the monitoring data, and then proposes solutions. The solution is using relative method live testing as the supplementary of the online monitoring system.Then, through the simulation test and field test, effectiveness of the relative method live testing and the stability of the data are proved, and make clear it’s role in the fault analysis and diagnosis. The author cites the typical case of fault capacitive equipment to explain how to analysis and diagnosis the fault equipment by using the methods as online monitoring, relative method live testing and historical power-off test data. After that, the author put forward the corresponding method of data analysis. Finally, this paper summarizes the development situation of relative method live testing in Fuzhou area.