| 摘要 |
<p>The apparatus comprises an inverter which has a variable frequency input at 16, causing transistors T1 and T2 to switch. Transistor T2 supplies current to the motor M through an isolating capacitor C2, and has a bootstrap capacitor C3 providing positive feedback to maximise its voltage swing. A resistor RE is provided in series with the motor to reduce current flow at its midrange resonance. The bootstrapping, particularly in conjunction with the series resistor, gives satisfactory operation of the motor over a wider range of frequency than known transistorised inverters for miniature motors, and thus a greater range of speed control. <IMAGE></p> |
