Identification of failure modes in interior permanent magnet synchronous motor under accelerated life test based on dual sensor architecture

Recently, the permanent magnet synchronous motors (PMSMs) are considered to be one of the best options for electrical motor due to their high power density and efficiency for various applications including industrial robot and smart mobility. However, the safety and reliability of the PMSM have not been verified sufficiently when compared to the conventional induction motor. The failure of electric motor can lead to catastrophic failure of entire system, so it is important to detect potential failure modes or signs in advance. In this paper, an accelerated life test was carried out to induce and investigate the failure modes of PMSM and various signals were monitored to detect the types of failure modes during the test. The shaft of the motor was radially loaded to accelerate the failure of PMSM. The phase current, temperature, displacement of the shaft, and vibration were monitored to estimate the health state of the motor. As a result, the bearing and the shaft were the most vulnerable components under radially loaded condition. Also, it is proved that the different failure modes can be successfully detected and classified by monitoring the phase current and vibration signal.