Impact of routing on the EMC behavior of a GaN HEMT-based full bridge DC-DC converter

In the perspective of upgrading the SOLEIL synchrotron accelerators, new electromagnet power supplies utilized for the control of the electron beam trajectory are being studied. For those implemented in the fastest beam orbit feedback loop, a new generation of low voltage, high frequency DC-DC converters based on Gallium Nitride (GaN) High Electron Mobility Transistors (HEMTs) is envisaged. One of the crucial points of their design concerns the routing of the switching cells, which is critical with respect to Electromagnetic Compatibility (EMC) and surge voltages, thus requiring a preliminary investigation. For this purpose, a routing model using the Ansys Q3D software is studied in this paper. The data from the Q3D simulation are compared to the experimental results for the prediction of the EMC performance of the DC-DC full-bridge converter. The EMC model resulting from this study allows analyzing the influence of the inter-cell parasitic inductances on the levels of the disturbances conducted in common and differential mode.