Simulation of air core pulse transformer

A high voltage air core pulse transformer was simulated using PSPICE program. The most common problem encountered in transformer winding insulation, that of insulation failure between windings, was modeled and simulated on the personal computer.Stray capacitance and turn-to-turn inter-winding capacitance, inductance, and resistance of the winding were incorporated to model the pulse transformer. Several results were obtained using different combination and variation of the model parameters. A voltage gradient because of the turn-to-turn capacitance was clearly noticeable across the output turns, which is believedto be responsible for premature breakdown of insulation, particularly between the output turns. It is shown that an introduction of capacitive voltage grading dish and a larger turn-to-turn winding capacitance can improve the voltage gradient and provide a more even voltage distribution across the entire transformer secondar winding.