| 摘要 |
PROBLEM TO BE SOLVED: To provide a compressor motor control device that changes the value and phase of current to be supplied to a coil of an excitation phase of a motor with excellent balance in conformity with the load torque of a rotor.SOLUTION: When the rotation speed of a rotor 5b increases to some extent during synchronization control in an electric motor 5, and sufficient induction current to detect the rotation angle of the rotor 5b flows through a coil 5d of phases other than the excitation phase, the rotation angle of the rotor 5b is detected by the induction current, and the phase of the current flowing in the coil 5d of the phases out of the excitation phase based on the detected rotation angle. Then, a motor torque is detected from the detected phase and the current value flowing in the coil 5d of the excitation phase in the synchronization control, during a period of switching the control of the electric motor 5 from the synchronization control to a sensorless vector control, the current value and phase of the current flowing in the coil 5d of the excitation phase is changed to a target current phase at which the motor torque is maximum, the corresponding target current value and the target current phase while maintaining the detected motor torque.SELECTED DRAWING: Figure 12 |
