Patent ID: 8610452
Filing Date: 2013-12-17
Classification: G01R,H02P

Abstract:
1. An apparatus for diagnosing a permanent magnet demagnetization of a permanent magnet synchronous motor, the apparatus comprising: a magnetic field generating unit generating magnetic fields at predetermined directions among a plurality of directions passing through a rotation axis of a rotor, on a plane vertical to the rotation axis of the rotor which is at standstill; a stator current measuring unit measuring values of currents which flow in a stator winding in correspondence with the respective generated magnetic fields; and a demagnetization diagnosing unit comparing a predetermined reference value and a comparison value which is calculated on the basis of the stator winding currents which are measured in correspondence with respective magnetic fields which are in opposite directions about the rotation axis of the rotor to diagnose demagnetization of a permanent magnet attached to the rotor.