PERMANENT MAGNET SYNCHRONOUS MACHINE CONTROL DEVICE, ELECTRIC VEHICLE, AND METHOD OF DETERMINING MAGNETIC POLE POLARITY OF PERMANENT MAGNET SYNCHRONOUS MACHINE

The purpose of the present invention is to make it possible to determine the polarity of a magnetic pole of a permanent magnet synchronous machine, irrespective of a decreasing or increasing characteristic of inductance due to a magnetic saturation phenomenon when a current is passed in a magnetic pole direction of the permanent magnet synchronous machine. This permanent magnet synchronous machine control device comprises a power converter which controls a permanent magnet synchronous machine, and a controller which controls the power converter. The controller is provided with: a voltage command generation unit which generates a voltage command for causing a desired current to flow through the permanent magnet synchronous machine; a current detection unit which detects a current that flows through the permanent magnet synchronous machine when the voltage command has been applied; and a magnetic pole position estimation unit which, on the basis of the current detected by the current detection unit, estimates the magnetic pole position of the permanent magnet synchronous machine. The magnetic pole position estimation unit is provided with a polarity determination unit which determines the polarity of a magnetic pole of the permanent magnet synchronous machine on the basis of the absolute value of an amount of change in the inductance value of the permanent magnet synchronous machine relative to an amount of change in the current detected by the current detection unit.