Device for driving a plurality of motors and electric apparatus including the same

A device for driving a plurality of motors, the device comprising:

• a first capacitor and a second capacitor serially connected to two ends of a DC terminal;
• an inverter connected to the two ends of the DC terminal;
• a multi-phase motor connected to the inverter;
• a single-phase motor serially connected with the multi-phase motor, and through which at least a part of current flowing through the multi-phase motor is configured to flow;
• and
• a controller configured to control the inverter,
• wherein, for starting the single phase motor during operation of the multi-phase motor, the controller is configured to
• perform an unbalancing control to change a voltage of a DC terminal neutral point between the first capacitor and the second capacitor, and
• align a rotor of the single-phase motor after performing the unbalancing control.

An electric apparatus comprising a device configured to drive a plurality of motors, the device comprising:

• a first capacitor and a second capacitor serially connected to two ends of a DC terminal;
• an inverter connected to the two ends of the DC terminal;
• a multi-phase motor connected to the inverter;
• a single-phase motor serially connected with the multi-phase motor, and through which at least a part of current flowing through the multi-phase motor is configured to flow;
• and
• a controller configured to control the inverter,
• wherein, for starting the single phase motor during operation of the multi-phase motor, the controller is configured to
• perform, during an alignment period, an alignment of a rotor of the single-phase motor and
• perform, during a voltage compensation period, a voltage compensation for compensating a voltage change of a DC terminal neutral point between the first capacitor and the second capacitor based on the alignment of the rotor of the single-phase motor.