Fault detection of eccentricity and bearing damage in a PMSM by means of wavelet transforms decomposition of the stator current

Abstract

This paper presents the study of permanent magnet synchronous machines (PMSM) running with eccentricity and bearings damage. The objective is to detect and identify the fault through the current signature analysis. The stator current has been analyzed by means of both Fourier (FFT) and Discrete Wavelet (DWT) transforms. Simulations have been carried out with a two-dimensional (2-D) finite element analysis (FEA), and they have been also compared with experiments. The results prove that the method proposed can be used to identify mechanical faults in a PMSM.

Faults and Diagnosis Methods of Permanent Magnet Synchronous Motors: A Review

“…Rosero et al have evaluated the degree of demagnetization of PMSM by calculating the energy in the detail of DWT [61]. And they also focused on mechanical faults [70]. Obeid et al used the method based on WT to identify the short circuit winding phase in PMSM [71].…”

Stator current based indicators for bearing fault detection in synchronous machine by statistical frequency selection

“…݂ (only the first 20 multiples of the rotation frequency have been included). This frequency family can be generalized and re-written by taking into account the modulation of the current harmonics by the mechanical rotation frequency as shown in (9) ‫ܨ‬ = (6݇ ± 1)݂ ௦ ± ݂ (9) Figure 12 and Fig.13 show the values of the indicator applied for family F c for two operating speeds of 14 100 rpm and 12 000 rpm at a sampling frequency of 10 kHz for one phase current. Only the last value of the cumulated indicator for each record is presented.…”

“…These applications are mainly dedicated to the induction machines. However, a few work deals with bearing fault detection in permanent magnet machines [8] [9].…”

Detection and Classification of Rotor Demagnetization and Eccentricity Faults for PM Synchronous Motors

“…For many PMSM applications, the motor operates under nonstationary conditions where the speed and load continuously change, making it difficult to extract (1) [4]- [6]. Time-frequency analysis techniques have been studied for reliable detection under these conditions [5], [6], [9]; however, it also increases the cost due to computation intensity and hardware requirements, making it difficult to apply for lowcost drive applications. Since it is the asymmetry in the flux pattern that induces the current component in (1), uniform demagnetization cannot be detected with MCSA.…”