Permanent magnet synchronous motor demagnetization fault diagnosis based on leakage radial magnetic density

Abstract A method of demagnetization fault diagnosis of permanent magnet synchronous motors is proposed by measuring the radial magnetic density of the leakage field at the external space point of the motor. The method enables non-invasive diagnosis of motor permanent magnet demagnetization faults compared to other methods. In this paper, an analytical model of the radial magnetic density of the leakage field of a surface-mounted permanent magnet synchronous motor under no-load conditions is proposed, and its accuracy is verified by simulation. The influence mode of demagnetization fault on the radial magnetic density of the leakage field is analyzed, which provides a new idea for the diagnosis of motor demagnetization fault.