| 摘要 |
<P>PROBLEM TO BE SOLVED: To efficiently detect induced current of a motor in a drive control circuit controlling driving of a synchronous motor. <P>SOLUTION: A differential amplifier 30 detects a coil current Is when the synchronous motor 20 steadily rotates. An application voltage S0 at that time is detected from an output of an ATT circuit 14 and so on. With the use of the coil current Is which is detected, the application voltage S0 at that time, and a predetermined scaling factor As, the induced current Ib is obtained by Ib=As×S0-Is. The application voltage to the motor is controlled based on the obtained induced current Ib. <P>COPYRIGHT: (C)2011,JPO&INPIT |
