Title: Design of a Compact Planar Rogowski Coil Current
Sensor

Presenter: Matthias Spieler was selected as the outstanding presenter in Technical Session 1: Design and Control of Power Converters at the 2024 CPES Annual Conference.

Research Advisor: Rolando Burgos

Abstract: This presentation investigates the utilization of a planar Rogowski coil located between the dc-bus traces to measure a half-bridge’s switching transient current. The sensor’s fundamentals are explained. Design considerations are derived from a comprehensive parametric study analyzing the impact of a non-uniform dc-bus current distribution on the sensor’s mutual inductance and the sensor’s impact on the current commutation loop stray inductance. A compact current sensor prototype is designed and fabricated for a SiC MOSFET half-bridge application. Simulations show a minimal increase in the current communication loop stray inductance of 399 pH and a summed mutual inductance of 1.15 nH between the dc-bus traces and the planar Rogowski coil. The current sensor’s performance is experimentally validated with double pulse tests.

Index Terms—Current measurement, Rogowski coil, Silicon carbide, Half-bridge