| 摘要 |
<P>PROBLEM TO BE SOLVED: To remove signals unnecessary for rotor position detection and enhance the accuracy of position detection over a wide operating range in a controller for permanent-magnet motor. <P>SOLUTION: A virtual neutral point voltage is obtained by a resistor R connected in parallel with the windings of the stator of a permanent-magnet motor 3. The differential voltage between the neutral point voltage (motor neutral point voltage) of the windings of the stator and the virtual neutral point voltage is passed through a band-pass filter 10 to obtain only signals required for position detection. The signals of differential voltage passed through the band-pass filter 10 are brought to a predetermined level through an amplifier circuit 6 and a comparator circuit 7 to obtain a position detection signal. This position detection signal is inputted to a control circuit 8 to detect a rotor position, and the excited stator winding is changed. <P>COPYRIGHT: (C)2004,JPO |
