Switch fault diagnosis and capacitor lifetime monitoring technique for DC–DC converters using a single sensor.

Owing to the key role of the power electronic converters in various applications, their reliability is an important issue. The electrolytic capacitor and the power switch are the most vulnerable components of the converters. On fault occurrence in these components, a suitable remedial strategy should be employed to prevent further damages. The first step in any remedial strategy is fault diagnosis including fault detection and identification. This study proposes a technique for switch fault diagnosis and capacitor lifetime monitoring in non‐isolated single‐switch DC–DC converters. The proposed cost‐effective method could be easily implemented using a printed circuit board Rogowski coil (PCBRC) on the capacitor terminals. The derivative of the capacitor current is captured by the PCBRC. The captured signal contains suitable signatures for detection of switch open‐circuit and short‐circuit faults. In addition to switch fault detection, lifetime of the converter capacitor is also monitored by the PCBRC via calculation of the capacitor equivalent series resistance. The proposed technique is implemented for a buck converter. The experimental results confirm the capability of the proposed technique for switch fault diagnosis and capacitor lifetime monitoring in non‐isolated single‐switch DC–DC converters. [ABSTRACT FROM AUTHOR]