| 摘要 |
<P>PROBLEM TO BE SOLVED: To carry out sensorless sine wave driving by V/f control, according to motor load torque. <P>SOLUTION: The direct-current power from a direct-current power source 1 is converted into alternating-current power through an inverter circuit 2 and a motor 3 is thereby driven to rotationally drive a motor load 4. A peak current corresponding to the peak value of motor current is detected by a current detecting means 5, and a peak current target value at which a predetermined current phase is obtained is set by a motor load current estimated by computation. The output voltage orthe output frequency of the inverter circuit 2 is controlled by a controlling means 6 so that a detected motor peak current becomes equal to the set value. <P>COPYRIGHT: (C)2009,JPO&INPIT |
