Study On Potential Distribution Of Reactor Windings Under VFTO And Lightning

In order to study the transient response of the transformer equipment under the Very Fast Transient overvoltage (VFTO) and the lightning in Gas-Insulated Substation (GIS), this paper adopts the representation of the winding by its individual turns to discribe conductor transmission line models of the transformer and reactor windings. A very efficient method, based on the principles of complex permeability, simplified finite element method is used to compute the elementary parameters of windings, which accounts for complex, anisotropic and frequency-dependent effective diamagnetic properties of the transformer and reactor windings. Regarding lines as several finite element units, the multi-conductor transmission line model Applys of the time-domain finite element method, taking the input impedance and capacitance of the coil-to-ground affection into consideration. The comparition of measurements and model provides feasibility and validation of the method.