WHEEL DIAMETER MEASURING APPARATUS OF ELECTRIC VEHICLE

摘要

A wheel diameter measuring apparatus for measuring a wheel diameter of an electric vehicle of speed sensorless vector control to which a synchronous motor is applied is obtained. A wheel diameter measuring apparatus of an electric vehicle comprising a synchronous motor driven by an electric power converter for converting a DC voltage into an AC voltage comprises a voltage detector for detecting an AC voltage generated by a magnetic field of the synchronous motor during coasting of the electric vehicle in which the electric power converter stops, and a calculation part for calculating a wheel diameter of a wheel driven by the synchronous motor from an AC voltage detected by the voltage detector and speed information about the electric vehicle.