Motor driver

A motor driver adapted to drive an AC motor having a stator core in which a plurality of slots arranged at equal intervals along an inner circumferential surface are formed, the motor driver comprising:

• an inverter adapted to convert a DC voltage into an AC voltage and apply the AC voltage to the AC motor;
• a DC voltage detector adapted to detect the DC voltage applied to the inverter;
• a voltage command generator adapted to generate a voltage command based on a torque command and a detection value of the DC voltage;
• and
• a gate signal generator adapted to generate a gate signal for performing pulse width modulation control of the inverter based on a comparison result between a modulated wave that is a waveform of the voltage command and a carrier wave, wherein
• number of slots per magnetic pole in the stator core is a natural number multiple of three, and
• there is a relationship of Fc=6n+3 between Fc and n, where Fc represents a numerical value as a carrier order obtained by normalizing frequency of the carrier wave with frequency of the modulated wave, and n is natural number.