| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of generating an electromagnetic sound having a desired tone from a motor.SOLUTION: A power unit includes an AC motor, a pulse width modulated inverter supplying the AC motor with AC power, and a control means controlling the pulse width modulated inverter and thereby regulating phase current that is the current flowing through a phase coil in the AC motor. With this power unit, the method generates the electromagnetic sound from the AC motor by causing a fluctuation to at least one voltage command value of a torque voltage command value Vq* and a magnetized voltage command value Vd* on the AC motor based on the ripple component of the phase current in the AC motor, wherein the tone of the electromagnetic sound generated from the AC motor is changed by changing a difference between a signal strength of modulated wave for modulating the phase current in the AC motor at the amplitude center and the signal strength of a carrier at the amplitude center using the pulse width modulated inverter and thereby changing a frequency component configuration of the ripple component of the phase current. |
