In this paper a high frequency power transformer model for network studies is presented. The model combines white and black box representations in a package implemented as “compiled foreign model” of MODELS language of EMTP/ATP program. This approach allows modelling all network components in EMTP/ATP environment. The time domain severity factor (TDSF) monitoring is integrated into the white+black box model package, which offers valuable information to figure out the risk level supported by inner points of power transformer windings when the unit interacts with the network during fast transient conditions. The proposed white+black box model of a 50/50/16.67 MVA transformer is illustrated while simulating the lightning overvoltages when it is connected to a 220 kV gas insulated substation (GIS).
Keywords: High frequency modelling, Power transformers, Network studies, Time Domain Severity Factor.
Published: August 2018.