Multiobjective Optimization and Enhanced Design of an Ω-Shaped Current Sensor for WBG Devices
Xia Du, Liyang Du, Yuxiang Chen, Andrea Stratta, Homer Alan Mantooth · IEEE Transactions on Power Electronics · 2025
The rapid evolution of wide bandgap devices has posed significant challenges in current sensor design concerning bandwidth, compact size, and intricate integrator design. This article presents a high-bandwidth Ω-shaped current sensor, consisting of an Ω-shaped copper tube, Rogowski coil and an external integrator, to achieve precise switching current measurement. The designed structure allows easy integration into various current paths. And a multiobjective optimization based on a genetic algorithm and a finite element method is developed for the comprehensive design of the Rogowski coil. Subsequently, three optimized solutions of coil geometry with bandwidth and sensitivity as optimization objectives are selected for comparison. Moreover, an external differential integrator and its associated design guide are introduced. Finally, comprehensive double pulse tests are performed under 800 V/70 A conditions. The test results of the three distinct coils validate the effectiveness of the proposed automated optimization methodology and external integrator design. The Ω-shaped current sensor consistently exhibits a faster response and maintains over 10 mV/A sensitivity compared with a 30-MHz commercial Rogowski coil.