| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor controller which can monitor the rotational speed of a hysteresis motor without generating any self-excited phenomenon as a filter circuit remains in the controller. SOLUTION: A motor controller for driving and controlling a hysteresis motor 3 has a variable-voltage and variable-frequency power supply unit 2 for converting the power fed from a commercial power supply 1 into the power having a desired voltage and frequency to output the converted power, a filter circuit having a capacitor 5 and provided in the output portion of the variable- voltage and variable-frequency power supply unit 2 to smooth its output, switching means 6, 7 for switching on or off the filter circuit, and a control circuit 9 for controlling the switching means 6, 7. The capacitance of the capacitor 5 of the foregoing filter circuit is so selected that the counter electromotive force of the hysteresis motor 3 which exceeds its rated voltage never occurs due to its self-excited phenomenon. |
