| 摘要 |
A reverse-phase-control power switching circuit provides for controlling the flow of current through a load, from an A.C. source, and includes circuitry for limiting the in-rush current for a load having a variation of resistance due to initial turn-on phenomenon. Load current is enabled to flow at each zero crossing of an A.C. source, connected in series with the load and the switching circuit of the present invention. Load current is terminated at a time, prior to the next source waveform zero crossing, to either maintain a substantially constant current conduction angle for a load with a substantially-constant steady-state resistance, or to limit load instantaneous current to a maximum level, set to a value somewhat greater than the desired normal load current, during low-load-resistance in-rush time intervals.
|
