| 摘要 |
<p>Electric motor control apparatus includes a variable-frequency oscillator 10, a counter 11 clocked by the oscillator, and signal generating means 12 arranged to generate two sinusoidal voltages in quadrature with one another. The two voltages are applied through separate amplifiers 22, 23 to separate stator windings 24, 26, of the motor, the stator windings being 90 DEG apart. Control means includes a bistable circuit 28 producing a signal lagging 45 DEG behind one sinusoidal voltage, and a phase sensitive detector 29 arranged to vary the frequency of the oscillator 10 to maintain a constant phase difference.</p> |
