Susceptibility Modelling of Flyback SMPS Transformer Input Stage Under High Current Pulse Injection

Abstract

This paper presents a model able to reproduce the behavior of the input stage of a switch-mode power supply (SMPS) under a high-level current pulse injected at its input in differential mode. Such high-level currents induce particular phenomena that manufacturer component models do not consider, especially regarding magnetic elements composing the EMC filter and the transformer. The paper focuses on the extraction of the transformer model considering saturation phenomena. The model is then integrated into Simplorer simulation software to simulate the propagation of high-level current pulse through a Flyback SMPS.