I want the circuit diagram of SCR based voltage regulator.AC and DC voltage regulators are required.They should contain SCR as rectifier in the circuit diagram
You say SCR regulator, then SCR as a rectifier. I am not familiar with any SCRs used as regulators, perhaps you mean a 3-terminal TO220 device (LM78xx) which looks like an SCR?
Won't using just one SCR block every half cycle? You can just use a diode for that (why use an SCR?), then a lowpass filter to smooth out the voltage between negative half cycles and follow that with a zener diode to clamp the voltage to get a DC regulator. We did this in a lab a couple years ago...isn't an transformer all that is needed for AC conversion? I'm not sure how you would regulat AC without distorting the waveform...
I have played around with a preregulator for a linear regulator. The preregulator "pass element" was two phase-controlled SCRs used as a full wave rectifier. The idea is to have a variable linear regulator (LM317), with the input voltage tracking the output, but about 5 volts higher, This allows high current at low output voltage without thermally overloading the LM317. It's basically a switching preregulator, running at mains frequency.
I think I got the idea from Jim Williams of National Semiconductor.
I might have the schematic "laying around" (on my hard drive).
This particular one has nothing to do with a triac. However, a triac can replace the two SCR to form the pre-regulator stage and that's the route I chose.