Open-switch fault detection and isolation of DC-AC static inverter feeding induction machine

Abstract

In the aim to ensure system reliability and monitoring of latent faults that decrease the installation's life and damage them in the short-term, this paper presents an online open-circuit switch fault diagnosis of a DC-AC inverter. The fault detection and isolation (FDI) employed method is articulated on two techniques based practically on stator currents analysis. For the first technique, the developed decision algorithm is based on d-q Park's vector components. In the second technique, fault diagnostic is achieved using normalised quantities of residues from the currents phases in ABC frame. When the open circuit switch fault occurs, the residual current vector between the stator currents with and without fault is calculated. After that, this vector will be evaluated by a decision algorithm. The drive chain modelling (power inverter-machine) and the monitoring algorithms are developed and established under the MATLAB/Simulink environment, where the results are presented and analysed. The feasibility and the effectiveness of the proposed techniques have been validated by simulation under different operating conditions.