Nanocrystallized cores for ground fault circuit breakers

Abstract Nanocrystallized cores for ground fault circuit breaker (GFCB) can be manufactured for low exciting fields such as 2 A/m, with a low sensitivity to varied pulsed waveform currents (Δ B dyn /Δ B sin ⩾0.85) and Δ B >0.1 T. On the basis of an experimental and statistical study, it is shown that these GFCB working features are mainly correlated to the remanent induction B r . The results allow a well-controlled design of compact and reliable GFCB transformers.