| 摘要 |
<p>A first tachometer generator or other alternator having at least two phases and at least two poles, wherein the output of the first tachometer generator is full wave rectified. A second tachometer generator is also provided having one phase and at least four poles. The output of the second tachometer generator is full wave rectified to provide a periodic wave to match to the fundamental ripple frequency at the output of the first tachometer generator rectifiers and/or to eliminate the fundamental. An outstanding feature of the disclosure is that ripple elimination is achieved independent of generator speed. This is especially desirable in a vast number of controls including, but not limited to, speed controls for electric or other motors. The reason that this is desirable is that the ripple fundamental can be a very low frequency at low speeds and cannot be easily or inexpensively removed by filters. If not removed, the ripple can have a serious adverse effect upon the dynamic response and accuracy of the system in which a tachometer generator is used.</p> |
