A Low Memory-Consuming Diagnosis Method for Multiple Open-Circuit Faults of Dual Three-Phase PMSM Drives

Existing current signal-based open-circuit fault diagnosis methods necessitate real-time analysis of extensive historical current data for fault feature extraction, which leads to large memory consumption and hinders practical online implementation. To mitigate this limitation, this study proposes a comprehensive open-circuit fault diagnosis method based on current trajectory characteristics for dual three-phase permanent magnet synchronous motor drives. It begins by classifying open-circuit faults into four scenarios according to their distribution patterns and analyzing the corresponding current trajectory characteristics under each fault scenario. The paper then divides the fault diagnosis process into three stages, fault detection, identification, and localization, and details the specific implementation method for each stage. The proposed method is able to diagnose multiple open-circuit faults in inverter and motor without addition hardware. Compared with existing methods, the proposed method demonstrates advantages in terms of computational efficiency, robustness to dynamic processes, and memory consumption. The experimental results verify the effectiveness and advantages of the proposed method.