Novel Device for Fast Detection and Limitation of Short-Circuit Currents in LVDC Grids

This paper introduces a novel non-destructive device for detecting and limiting short-circuit currents in LVDC grids. The proposed solution is based on the concept of using a transformer fully saturated by a permanent magnet during normal operation. When a short circuit condition occurs, the transformer desaturates, triggering the detection and protection mechanism. The function and structure of the unit as well as design criteria are explained. Experimental results demonstrate the effectiveness of the device in detecting and limiting overcurrents. This hardware-based detection solution is particularly suitable for being installed in a semiconductor circuit breaker rated up to but not limited to 100 A.