Abstract:In order to explore and solve the problem of influence of GIS disconnector operation on electronic transformer and acquisition device in intelligent substation, Firstly, the paper analyzes the mechanism of VFTO in the operation of GIS disconnector and its influence on electronic transformer, Then, EMTP simulation software is used to simulate the generation process of VFTO during the operation of disconnector. The software simulation results are analyzed in detail, and the distribution rule of VFTO during the operation of disconnector is obtained.According to the distribution rule obtained by simulation, this paper puts forward the solution of suppression by adding overvoltage suppression design in power port, adopting three-level protection circuit in signal port, optimizing box structure and shield design, optimizing data acquisition and control algorithm, etc.. Simulation results shows that the scheme can effectively restrain the VFTO generation during the operation of disconnector, minimize the influence of VFTO on electronic transformer and acquisition device, reduce the workload of maintenance, and improve the reliability of electronic transformer in intelligent substation.