SCR constant output voltage?

Question

How can an SCR mantain a constant voltage output from a generator? Please explain the construction. Thank you.

Answer 1

It works similar to a typical diode, but is controlled similar to a bipolar transistor as far as connections go. Connection points are Anode [A], Cathode [K], and Gate [G]. Physical makeup: The SCR is made up of two "P-N" junctions with a "Gate" attachment between them (a normal diode [power type semiconductor diode] has one P-N junction). The gate is connected between the two P-N junctions with a current waiting in the forward bias direction [+ to -] and the voltage is above 1-volt. A momentary pulse to the gate will cause the SCR to conduct and current will flow across the device until the value changes. If this happens, the gate needs to be pulsed again to cause conduction to resume; otherwise no current will flow across the device. If used on AC, the device needs to be triggered [fired] in relationship to the points on the sine wave that conduction is requested. Example: to chop a wave to be 1/2 peak, the SCR gate will need to be pulsed with either a high-logic pulse or a positive-voltage pulse until the AC wave reaches 50% of peak value in the positive flowing direction.