Magnet flux amount estimation device, abnormal demagnetize determination device, synchronous motor driving device, and electric motor car

摘要

According to one embodiment, a magnet flux amount estimation device includes a magnetic pole position detector (8) configured to detect a magnetic pole position of a permanent magnet synchronous motor (7) including a permanent magnet within a rotor; an inductance-equivalent value determination module (10) configured to determine an inductance-equivalent value of a d-axis corresponding to a determined magnetic pole direction; and a magnet flux amount estimator (11) configured to calculate an estimation value of a magnet flux amount of the permanent magnet, based on the inductance-equivalent value.