MOTOR DRIVE OF WASHING MACHINE

摘要

PROBLEM TO BE SOLVED: To increase torque during fast rotation, improve efficiency during slow rotation and miniaturize a motor by achieving energy savings by varying torque-rotation speed characteristics of the motor to enable constant torque control using a motor drive of a washing machine which drives the motor by means of an inverter circuit. SOLUTION: The DC power of a rectifying circuit 2 connected to an AC power supply 1 is converted by the inverter circuit 3 into AC power, which is then applied to the motor 4 so that an agitator or a washing/drying drum is driven by the motor 4. The rotor position of the motor 4 is detected by a rotor position detecting means 4a, the motor current is detected by a current detecting means 5, and the inverter circuit 3 is controlled by a control means 6. The control means 6 decomposes the motor current into a current component corresponding to magnetic flux and another current component corresponding to torque. The current component corresponding to magnetic flux and the current component corresponding to torque are controlled according to the rotation speed of the motor 4.