Magnetic field measurement for contactless current sensing in power electronic converters

Current sensing plays an important role in power electronics for both protection and control of power electronic converters. This paper proposes an approach for detecting short-circuit (SC) events through the measurement of the magnetic field radiated by power converters. Two magnetic field sensor technologies (AMR and induction coils) were evaluated. The magnetic field mapping over the PCB is carried out to estimate favorable positions for detecting SC events. The obtained results show that the induction coil is a promising candidate, not only for detecting a SC event but also for performing contactless current measurement in power converters. This work plans to develop the integration of contactless current sensors for power converters, or for intelligent drivers integrating protection against SC event (or over-currents), especially dedicated to wide band gap devices such as GaN and SiC materials which could have lower SC robustness compared to silicon.