Power conversion device and power conversion method

A power conversion method comprising:

• generating a fundamental wave for generating one-phase AC power of three-phase AC power for each of three inverters configured to convert DC power of a DC bus into single-phase AC power, the fundamental wave having a fundamental frequency;
• generating, for each of the three inverters, an adjustment wave having a frequency that is triple the fundamental frequency of the fundamental wave;
• adding, for each of the three inverters, the adjustment wave to the fundamental wave to generate a phase voltage, wherein an initial phase of the adjustment wave is offset from an initial phase of the fundamental wave so as to reduce a voltage ripple occurring in the DC bus at double the fundamental frequency of the fundamental wave;
• and
• outputting, for each of the three inverters, the phase voltage to generate the three-phase AC power.

A non-transitory memory device having instructions stored thereon that, in response to execution by a controller, cause the controller to perform operations comprising:

• generating a fundamental wave for generating one-phase AC power of three-phase AC power for each of three inverters, each of the three inverters configured to convert DC power of a DC bus into single-phase AC power, the fundamental wave having a fundamental frequency;
• generating, for each of the three inverters, an adjustment wave having a frequency that is triple the fundamental frequency of the fundamental wave;
• adding, for each of the three inverters, the adjustment wave to the fundamental wave to generate a phase voltage, wherein an initial phase of the adjustment wave with respect to the fundamental wave is offset from an initial phase of the fundamental wave so as to reduce a voltage ripple occurring in the DC bus at double the fundamental frequency of the fundamental wave;
• and
• outputting, for each of the three inverters, the phase voltage to generate the three-phase AC power.