Current kernel density estimation based transistor open‐circuit fault diagnosis in two‐level three phase rectifier

Abstract

Two‐level three phase rectifiers are widely used in industrial applications due to their superior performance. Their reliability has attracted lots of attention in recent decades. Transistor is one of the most fragile component because they suffer from voltage surge and thermic cycling. A fault diagnosis method based on current kernel density estimation for transistor open‐circuit faults is proposed. The proposed method needs no extra sensors and it includes three steps: current kernel density estimation, Euclidean distance, fault detection and isolation. Experimental results show the proposed diagnosis method is highly efficient in single open‐circuit fault and multiple open‐circuit fault on the same leg.