A power conversion device comprising: power conversion circuitry configured to perform a power conversion for outputting a driving power to an induction motor , wherein the induction motor comprises a rotor , a first group of primary coils , and a second group of primary coils isolated from the first group of primary coils ; and characterized by control circuitry configured to: receive a master command phase from a master power conversion device , wherein the master power conversion device controls a master power conversion circuitry to output a master driving power to the first group of primary coils , based on a master voltage command having the master command phase in a master rotating coordinate system for driving the rotor ; generate a voltage command having a command phase in a rotating coordinate system based on a torque target value, wherein a rotating magnetic field for driving the rotor is generated to rotate with the rotating coordinate system; calculate a rotation phase of the rotating coordinate system based on a command phase difference between the master command phase and the command phase to reduce the command phase difference; and control the power conversion circuitry to output the driving power to the second group of primary coils , based on the rotation phase and the voltage command. power conversion circuitry configured to perform a power conversion for outputting a driving power to an induction motor , wherein the induction motor comprises a rotor , a first group of primary coils , and a second group of primary coils isolated from the first group of primary coils ; and characterized by control circuitry configured to: receive a master command phase from a master power conversion device , wherein the master power conversion device controls a master power conversion circuitry to output a master driving power to the first group of primary coils , based on a master voltage command having the master command phase in a master rotating coordinate system for driving the rotor ; generate a voltage command having a command phase in a rotating coordinate system based on a torque target value, wherein a rotating magnetic field for driving the rotor is generated to rotate with the rotating coordinate system; calculate a rotation phase of the rotating coordinate system based on a command phase difference between the master command phase and the command phase to reduce the command phase difference; and control the power conversion circuitry to output the driving power to the second group of primary coils , based on the rotation phase and the voltage command. receive a master command phase from a master power conversion device , wherein the master power conversion device controls a master power conversion circuitry to output a master driving power to the first group of primary coils , based on a master voltage command having the master command phase in a master rotating coordinate system for driving the rotor ; generate a voltage command having a command phase in a rotating coordinate system based on a torque target value, wherein a rotating magnetic field for driving the rotor is generated to rotate with the rotating coordinate system; calculate a rotation phase of the rotating coordinate system based on a command phase difference between the master command phase and the command phase to reduce the command phase difference; and control the power conversion circuitry to output the driving power to the second group of primary coils , based on the rotation phase and the voltage command. <EOS>