Abstract: A drive system includes a current detection unit that detects a current flowing to a main synchronous motor, and a current detection unit that detects a current flowing to a secondary synchronous motor. The drive system includes a magnetic pole position estimation unit that estimates the magnetic pole position of the rotor of the main synchronous motor, and a magnetic pole position estimation unit that estimates the magnetic pole position of the rotor of the secondary synchronous motor. The drive system includes a current control unit that outputs a voltage command, and a secondary torque current pulsating component extraction unit that extracts a pulsating component. The drive system includes a subtracter that determines an angle difference, and a magnetic flux current command determination unit that determines a magnetic flux current command.

Abstract: A synchronous motor drive device drives a plurality of synchronous motors, and includes a power converter that converts power to supply power to the plurality of synchronous motors, a first switch device that electrically connects or disconnects between the power converter and each of the plurality of synchronous motors, and a controller that, based on a higher order command, performs stability judgment processing of the plurality of synchronous motors, determines the number of synchronous motors to be driven and a drive speed from among the plurality of synchronous motors, selects a synchronous motor corresponding to the number of the synchronous motors from among the plurality of synchronous motors, controls the first switch device corresponding to the selected synchronous motor to electrically connect the power converter to the synchronous motor and to supply the power, and instructs, to the power converter, the drive speed of the synchronous motor to be driven.

Abstract: A drive system includes a current detection unit that detects a current flowing to a main synchronous motor, and a current detection unit that detects a current flowing to a secondary synchronous motor. The drive system includes a magnetic pole position estimation unit that estimates the magnetic pole position of the rotor of the main synchronous motor, and a magnetic pole position estimation unit that estimates the magnetic pole position of the rotor of the secondary synchronous motor. The drive system includes a current control unit that outputs a voltage command, and a secondary torque current pulsating component extraction unit that extracts a pulsating component. The drive system includes a subtracter that determines an angle difference, and a magnetic flux current command determination unit that determines a magnetic flux current command.

Abstract: A synchronous motor drive device drives a plurality of synchronous motors, and includes a power converter that converts power to supply power to the plurality of synchronous motors, a first switch device that electrically connects or disconnects between the power converter and each of the plurality of synchronous motors, and a controller that, based on a higher order command, performs stability judgment processing of the plurality of synchronous motors, determines the number of synchronous motors to be driven and a drive speed from among the plurality of synchronous motors, selects a synchronous motor corresponding to the number of the synchronous motors from among the plurality of synchronous motors, controls the first switch device corresponding to the selected synchronous motor to electrically connect the power converter to the synchronous motor and to supply the power, and instructs, to the power converter, the drive speed of the synchronous motor to be driven.