Analytical design and simulation for switching transformer in high-voltage applications

Resonant converters are interesting topologies for high voltage power supplies because of their advantages such as soft switching and high power density. In order to increase the voltage to dozens of kilovolts or even more, it is necessary to use a high step-up transformer in high voltage power supplies; therefore, the parasitic parameters of the transformer cannot be neglected. So, the most important part in the high voltage resonant converter is high voltage transformer. This paper presents a method for LCLC resonant converter designing according to employing parasitic parameters of transformer as resonant circuit components in order to reduce weight and size of the converter. Converter behavior cannot be predicted without calculating the exact value of parasitic parameters of the transformer such as leakage inductance and stray capacitance. This case is focused on calculating the parasitic parameters of transformer, simulation using Finite Element Method (FEM) and using the results for design an LCLC converter. The experimental results that obtained from 250W, 12KV prototype verified simulation results for LCLC fixed frequency resonant converter.