Effect of inverter fault on distribution of electromagnetic field for permanent magnet synchronous motor

Safe and reliable of inverter is directly related to the normal operation of permanent magnet synchronous motor drive system. Therefore, in the paper, taking a 12.5kW Permanent Magnet Synchronous Motor (PMSM) as the research object, two-dimensional transient electromagnetic field calculation model based on vector control strategy is established, and the corresponding assumptions and boundary conditions are also given. By adopting field circuit coupled calculation method, electromagnetic field is theoretically calculated under inverter normal and short circuit fault (SCF) in the upper switch of phase A, respectively. Simultaneously, due to the SCF, DC components are produced in three phase current, and the influence of the magnetic field produced by DC components on air gap magnetic field is analyzed in detail. In order to validate the accuracy of the established calculation model, some relevant experiments have been conducted. The obtained conclusion can provide theoretical basis for drive system fault diagnosis of PMSM.