Biblio

Interface transformer used in asynchronous networking was a kind of special transformer which's different from normal power transformer. During no-load switch-in, the magnitude of inrush current will be high, and the waveform distortion also be severity. Maybe the protections will be activated, even worse may lead the lockdown of the DC system. In this paper, field-circuit coupled finite element method was used for the study of transient characteristic of no-load switch-in, remanence simulation methods were presented. Quantitative analysis of the effect of closing making angle and core remanence on inrush current peak value, meanwhile, the distribution of magnetic field inside the tank during the transient process. The result indicated that the closing making angle and core remanence have obvious effect on inrush current peak value. The research results of this paper can be used to guide the formulation of no-load switch-in strategy of interface transformer, which was of great significance to ensure the smooth operation of HVDC Flexible system.