Motor control device, motor control method, hybrid system, boost converter system, and electric power steering system

A motor control device that controls driving of an AC motor connected to a power converter performing power conversion from DC power to AC power, the AC motor driven using the AC power, comprising:

• a carrier wave generation unit that generates a carrier wave;
• a carrier wave frequency adjustment unit that adjusts frequency of the carrier wave;
• a PWM control unit that performs pulse width modulation using the carrier wave on a voltage command corresponding to a torque command to generate a PWM pulse signal for controlling operation of the power converter;
• and
• a circular order selection unit that selects one of a plurality of circular orders based on magnitude of vibration for each circular order, wherein:
• the carrier wave frequency adjustment unit adjusts the frequency of the carrier wave so as to change a phase difference between the voltage command and the carrier wave based on the magnitude of the vibration for each circular order of electromagnetic excitation force generated circularly in a radial direction of the AC motor;
• and
• the carrier wave frequency adjustment unit determines a phase shift amount according to the circular order selected by the circular order selection unit and adjusts the frequency of the carrier wave so as to change the phase difference between the voltage command and the carrier wave according to the determined phase shift amount.

A motor control method for controlling driving of an AC motor connected to a power converter performing power conversion from DC power to AC power, the AC motor driven using the AC power, comprising:

• adjusting frequency of a carrier wave so as to change a phase difference between a voltage command corresponding to a torque command for the AC motor and the carrier wave based on magnitude of vibration for each circular order of electromagnetic excitation force generated circularly in a radial direction of the AC motor,
• generating the carrier wave at the adjusted frequency, and
• performing pulse width modulation using the carrier wave on the voltage command to generate a PWM pulse signal for controlling operation of the power converter;
• wherein the magnitude of the vibration for each circular order is determined based on a rotation speed of the AC motor, the torque command, and a voltage of the DC power.

A motor control method for controlling driving of an AC motor connected to a power converter performing power conversion from DC power to AC power, the AC motor driven using the AC power, comprising:

• adjusting frequency of a carrier wave so as to change a phase difference between a voltage command corresponding to a torque command for the AC motor and the carrier wave based on magnitude of vibration for each circular order of electromagnetic excitation force generated circularly in a radial direction of the AC motor,
• generating the carrier wave at the adjusted frequency, and
• performing pulse width modulation using the carrier wave on the voltage command to generate a PWM pulse signal for controlling operation of the power converter;
• wherein:
• one of a plurality of circular orders is selected based on the magnitude of the vibration for each circular order;
• a phase shift amount is determined according to the selected circular order;
• and
• the frequency of the carrier wave is adjusted so as to change the phase difference between the voltage command and the carrier wave according to the determined phase shift amount.