MODELING OF WIDE FREQUENCY CHARACTERISTIC OF POTENTIAL TRANSFORMER

In substations, Switching operation will give rise to transient overvoltage. For prediction of the interference voltage in the secondary circuits of a potential transformer caused by the transient overvoltage in substation maincircuit, the wide frequency model for the transfer function of the potential transformer (PT) should be constructed. In the paper, a modified transfer function synthesis method is presented. After measuring the transfer characteristic of the PT, the wide frequency model of the PT can be set up with the synthesis method. The method is simple and effective; it can be used to constructed the wide frequency models for the transfer function of the coupling capacitor voltage transformer (CCVT) as well.