Design Study of a High-Permeability Core-Based Ultra-Compact Tesla Transformer

Abstract

A compact Tesla transformer has been designed and developed using analytical calculations and simulations. Unlike conventional Tesla transformers, this transformer employs a high-permeability core to enhance the coupling and facilitate the use of semiconductor switches to increase the pulse repetition rate. In order to achieve compactness, the core of the transformer has been designed in such a way to work as a pulse-forming line (PFL) also. The effect of insulating materials like transformer oil and SF6 on the pulse rise time and pulse duration of the PFL has been studied. A fair comparative study between a discrete transformer without the metal enclosure and when encapsulated inside a PFL has also been carried out. A comprehensive study based on simulation is also presented to visualize the nonuniform current density of the primary coil. The designed transformer is capable of delivering a 140-kV voltage pulse of duration (FWHM) 10 ns on a 60- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula> load for an input voltage of 700 V. The experimental results were compared with the analytical and simulation modeling results and a good agreement has been demonstrated.