A laundry treatment apparatus is disclosed. The laundry treatment apparatus includes a cabinet (100) defining the appearance of the laundry treatment apparatus, a drum (300) rotatably disposed in the cabinet (100), and a drive unit (400) for rotating the drum (300), wherein the drive unit (400) includes a first drive unit (410) for generating rotational force required to rotate the drum (300), and a second drive unit (430) for changing the ratio of rotational force generated by the first drive unit (410) and rotational force transferred to the drum (300), wherein the first drive unit (410) includes a first stator (411) for generating rotating magnetic fields, a magnetic flux converter (413) rotatably disposed radially outside the first stator (411) to change the magnetic flux of the magnetic fields generated by the first stator (411), and a first rotor (415) disposed radially outside the magnetic flux converter (413) and rotatable by the magnetic fields, wherein the magnetic flux converter (413) is configured to rotate with the second drive unit (430).

A laundry treatment apparatus is disclosed. The laundry treatment apparatus includes a cabinet (100) defining the appearance of the laundry treatment apparatus, a drum (300) rotatably disposed in the cabinet (100), and a drive unit (400) for rotating the drum (300), wherein the drive unit (400) includes a first drive unit (410) for generating rotational force required to rotate the drum (300), and a second drive unit (430) for changing the ratio of rotational force generated by the first drive unit (410) and rotational force transferred to the drum (300), wherein the first drive unit (410) includes a first stator (411) for generating rotating magnetic fields, a magnetic flux converter (413) rotatably disposed radially outside the first stator (411) to change the magnetic flux of the magnetic fields generated by the first stator (411), and a first rotor (415) disposed radially outside the magnetic flux converter (413) and rotatable by the magnetic fields, wherein the magnetic flux converter (413) is configured to rotate with the second drive unit (430).

A vehicle speed control unit includes feedback control parts, the number of feedback control parts corresponding to the number of multiple motors, generating feedback command torques for the respective motors, on the basis of respective deviations between speed signals from speed sensors detecting revolution speeds of the multiple motors and feedback target vehicle-speed signal reshaped from the inputted target vehicle-speed signal by target vehicle-speed filters; a feedforward control part calculating a feedforward command torque for the vehicle as a whole, on the basis of the inputted target vehicle-speed signal; and a torque distribution part dividing the feedforward command torque into individual feedforward command torques for distribution to the respective motors, wherein the individual feedforward command torques are respectively added to the feedback command torques and, to control the respective motors.

A vehicle speed control unit includes feedback control parts, the number of feedback control parts corresponding to the number of multiple motors, generating feedback command torques for the respective motors, on the basis of respective deviations between speed signals from speed sensors detecting revolution speeds of the multiple motors and feedback target vehicle-speed signal reshaped from the inputted target vehicle-speed signal by target vehicle-speed filters; a feedforward control part calculating a feedforward command torque for the vehicle as a whole, on the basis of the inputted target vehicle-speed signal; and a torque distribution part dividing the feedforward command torque into individual feedforward command torques for distribution to the respective motors, wherein the individual feedforward command torques are respectively added to the feedback command torques and, to control the respective motors.

An electric motor system includes a drive shaft, a first electric motor, a second electric motor, a first inverter, a second inverter and a control unit. The drive shaft is rotatable around an axis. The first electric motor and the second electric motor rotate the drive shaft. The first inverter supplies power in order to generate a torque to the first electric motor. The second inverter supplies power in order to generate a torque to the second electric motor. The control unit controls the first inverter and the second inverter. The controller is configured to be able to change a ratio between an output torque of the first electric motor and an output torque of the second electric motor.

An electric motor system includes a drive shaft, a first electric motor, a second electric motor, a first inverter, a second inverter and a control unit. The drive shaft is rotatable around an axis. The first electric motor and the second electric motor rotate the drive shaft. The first inverter supplies power in order to generate a torque to the first electric motor. The second inverter supplies power in order to generate a torque to the second electric motor. The control unit controls the first inverter and the second inverter. The controller is configured to be able to change a ratio between an output torque of the first electric motor and an output torque of the second electric motor.

A PN-busbar common system includes motor drive devices for a plurality of motors, each of which is supplied with power from a common PN-busbar, where the motor drive devices individually drive the corresponding motors. Each of the motor drive devices executes a regenerative control on a basis of a regenerative-control start voltage, and controls to stop the regenerative control on a basis of a regenerative-control stop voltage, and also individually calculates a regenerative load ratio to control to enable or disable the regenerative control on a basis of a result of a comparison between a calculated regenerative load ratio and a set regeneration-capable load ratio.

A PN-busbar common system includes motor drive devices for a plurality of motors, each of which is supplied with power from a common PN-busbar, where the motor drive devices individually drive the corresponding motors. Each of the motor drive devices executes a regenerative control on a basis of a regenerative-control start voltage, and controls to stop the regenerative control on a basis of a regenerative-control stop voltage, and also individually calculates a regenerative load ratio to control to enable or disable the regenerative control on a basis of a result of a comparison between a calculated regenerative load ratio and a set regeneration-capable load ratio.

An electric circuit for use in the control and drive of at least one electric motor, the circuit comprises a first lane comprising a first set of motor windings that are driven by a motor drive bridge that comprises a network of drive stage switches that selectively connect each phase of the lane to either a first supply voltage or a first supply ground, and further comprising a control circuit that controls the switches of the drive stage, the control circuit being powered by an isolated first lane power supply that has a first floating ground, and a second lane comprising a second set of motor windings that are driven by a motor drive bridge that comprises a network of drive stage switches that selectively connect each phase of the lane to either a supply voltage or a supply ground, and further comprising a control circuit that controls the switches of the drive stage, the control circuit being powered by an isolated second lane power supply that has a second floating ground. The first and second control circuits in use exchange digital control signals such that the control circuit of each lane can monitor the function of the other lane, and the two floating grounds and the two lane grounds are connected together through a potential divider network that holds the two floating grounds at a potential that is between the potential of the lane grounds for the two lanes.

An electric circuit for use in the control and drive of at least one electric motor, the circuit comprises a first lane comprising a first set of motor windings that are driven by a motor drive bridge that comprises a network of drive stage switches that selectively connect each phase of the lane to either a first supply voltage or a first supply ground, and further comprising a control circuit that controls the switches of the drive stage, the control circuit being powered by an isolated first lane power supply that has a first floating ground, and a second lane comprising a second set of motor windings that are driven by a motor drive bridge that comprises a network of drive stage switches that selectively connect each phase of the lane to either a supply voltage or a supply ground, and further comprising a control circuit that controls the switches of the drive stage, the control circuit being powered by an isolated second lane power supply that has a second floating ground. The first and second control circuits in use exchange digital control signals such that the control circuit of each lane can monitor the function of the other lane, and the two floating grounds and the two lane grounds are connected together through a potential divider network that holds the two floating grounds at a potential that is between the potential of the lane grounds for the two lanes.