Patent ID: 8912739

Claim:
A synchronous machine control apparatus comprising: an electric-power conversion unit that outputs a voltage to a synchronous machine having a permanent magnet for forming a magnetic field, based on a voltage command; a current detection unit that detects an armature current of the synchronous machine; a voltage command calculation unit that calculates the voltage command, based on a control command; a position detection unit that estimates or detects a rotor position of the synchronous machine; a magnetic flux estimation device that estimates a γ axis in which a total armature-interlinked magnetic flux of the synchronous machine is generated, based on at least one of the armature current and the voltage command; and a magnet condition estimation unit that estimates a temperature and a magnetic flux of the permanent magnet, wherein the magnet condition estimation unit coordinate-converts the armature current into currents on a γ-δ axis consisting of the γ axis and a δ axis that is perpendicular to the γ axis, based on the rotor position and the estimated γ axis, and estimates the temperature and the magnetic flux of the permanent magnet, based on the control command and the γ-δ axis currents.