ABSTRACT
The voltages applied to a transformer's terminals can be broadly classed as steady state or “transient.” The “transient” voltages a transformer experiences are commonly classified as dynamic, transient, and very fast transients. Transient voltage refers to class of excitation caused by events like lightning surges, switching events, and line faults causing voltages of the chopped waveform. The transient-voltage distribution is a function of the applied voltage excitation and the transformer's physical shape and material content. The accurate prediction of the transient-voltage response of coils and winding has been of interest for over 100 years. Constructing this lumped-parameter model and solving for the resultant transient voltages are challenging since the resultant set of differential equations is challenging to solve. The transient response of the coil is the voltage the coil experiences as coil transitions between initial voltage distribution and steady-state distribution. Starting with the inductances, capacitances, and resistive elements, equations reflecting the transformer's transient response can be written in numerous forms.
