Analysis of a Case of Tap Fault Encountered by a Tap Changer of an Actual Converter Transformer
This paper focuses on seeking the reason that causes tap faults of converter transformer tap changers through an actual fault case.It first reports the difference between the mechanical tap position and the transmitted tap signal which was observed after fault occurrence by on-site examination and its underlying mechanism,as well as the analysis on the fault cause on the basis of inspection results of relevant equipment.It further gives explanation to the unexpected action of tap changer during the fault process by using the principle of automatic control synchronization of the tap changer.Addi-tionally,it puts forward suggestions on maintenance measures of converter transformer tap changers.