| 摘要 |
<p>706,414. Automatic speed control systems. BRITISH THOMSON-HOUSTON CO., Ltd. Nov. 26, 1951 [Dec. 13, 1950], No. 30446/50. Drawings to Specification. Class 38 (4) The invention relates to Ward-Leonard systems for controlling speed in response to the difference between a reference voltage and a speed representative voltage, the normal speed voltage being greater than the main-generator-exciter system voltage. The speed-representative-voltage is taken from a potentiometer across, e.g. the main generator, and is maintained at a substantially constant value at all speeds, while the voltage across generator rises as the potentiometer tapping is reduced at high speed. Thereby the full generated voltage is used at low speeds, and provides close control. The speed-representative voltage may alternatively be provided by a tachogenerator, and the exciter may be an amplidyne or magnetic amplifier.</p> |
