| 摘要 |
<p>A method and circuit as disclosed herein for varying the current to N electrical loads by the use of SCR's, the arrangement being such that the total current is sinusoidal and of uniform amplitude at a particular setting. The technique involves the steps of generating a load sequence waveform, the period of which is nN full cycles of the ac source where n is any positive integer, and, during each period of the waveform, generating a load firing pattern for initiating the flow of a current I in each load, the load pattern being such that (a) the currents in each of the loads are initiated at instants which are n full cycles of the ac source apart, and (b) maintaining the current in each load for d full cycles of the ac source, where d is a duty factor and is any positive integer equal to or greater than n, but less than or equal to nN, whereby the total current drawn from the ac source is uniform and equal to dI/n.</p> |
