Detection and Identification of Switching Faults in Boost Converters Using an HSVG Sensing Circuit

The boost converter is a fundamental power converter topology, particularly in non-isolated DC-DC applications such as solar PV power optimizers and battery interfacing converters. As semiconductor devices represent the most failure-prone components in these converters, realtime monitoring of their health is essential for ensuring system reliability, effective maintenance, and prompt fault protection. This paper proposes a novel high-speed, variablegain (HSVG) sensing circuit designed to monitor the switching node voltage during both MOSFET ON and OFF states. A multi-threshold fault diagnosis method is introduced to accurately distinguish between short-circuit and open-circuit faults in both MOSFET and Diode. The proposed sensing circuit is validated under static and dynamic conditions. Experimental testing using a boost converter demonstrates the circuit's ability to rapidly detect and accurately identify all relevant fault modes. The results confirm the effectiveness and robustness of the proposed failure diagnosis approach.