摘要 |
The ac voltage regulator apparatus of the present invention uses back-to-back silicon-controlled rectifier ("SCR") power output switches which are triggered into conduction after being delayed for a period of time from the previous ac supply voltage zero point. The SCR switches are switching the load voltage at a determinate phase angle in order to obtain a constant true RMS voltage. The delay time of the trigger signal is variable and is changed to obtain regulation of the RMS voltage applied to the ac load. This regulation feature compensates for temperature changes, ac supply voltage variations, and ac load current changes. |