IPMSM demagnetization fault diagnosis based on ultra-low sampling frequency data re-indexing restoration method
摘要
Voltage and current are commonly sampled signals for the diagnosis of permanent magnet synchronous motor (PMSM) demagnetization faults (DMF). Traditionally, external signal capture interfaces (ESCIs) have been a common choice; however, these devices have been hindered by noise interference, sampling errors, and high costs. This study pioneers the concept of ultra-low sampling frequency data (ULSD) and presents a novel approach to re-index and reconstruct voltage and current waveforms using the ULSD re-indexing method. Utilizing demagnetization flux linkage curves to derive back-electromotive force (Back-EMF) characteristics for establishing a demagnetization model. Crucially, the zero-cross offset (ZCO) is used to determine the period sampling points (PSPs), after which the data index is redefined. The waveform is then reconstructed based on a sampling period offset as a condition. Finally, the rearranged ULSD waveforms are integrated into a 1D CNN for practical DMF diagnosis. The primary contribution of this study is the effective reconstruction of Back-EMF waveforms using the ULSD re-indexing method. When applied to a 1D CNN for diagnosis, the data obtained from the ULSD re-indexing method achieve a recognition rate of 85.25%, outperforming the data from the ESCI method.