| 摘要 |
<p>A vibratory feeder includes a vibrator and a variable frequency drive. The vibrator includes an inductor coil and an armature. The inductor coil, when energized by a current, attracts and displaces the armature to perform mechanical work. The variable frequency drive powers the vibrator and includes an inverter, current-blocking device, and capacitor. The inverter includes a DC bus and generates a relative sine wave current including positive half-cycles energizing the inductor coil and negative half-cycles whereby the inductor coil is de-energized. The current-blocking device is connected in series with the inductor coil and blocks current to the inductor coil during the negative half cycles. The capacitor is connected in parallel with the DC bus and captures a portion of a counter EMF resulting from de-energizing the inductor coil during negative half-cycles. The capacitor discharges the captured portion of the counter EMF to reenergize the inductor coil during subsequent positive half-cycles.</p> |
