power supply output voltage 12v using silicon controlled rectifier?

[DiegoSilang]

Hi I'm having trouble with this circuit schematic. It seems that the fuse at the scr rectifier bridge always breaks. I'm trying to get an output of 12V AC-DC. Also I'm trying to make an actual circuit using this multisim simulation. Is there something wrong with the connections? Any help would be much appreciated.

[johnsold]

It looks like the load resistor is R14 = 0.24 ohms. It is connected to a 220 VAC source when the SCRs are conducting.  Unless Ohm's Law has changed recently, that is over 900 A.

Was R14 supposed to be a current measuring shunt that got connected parallel to the load rather than in series?

It will be difficult to get a 12 VDC output from the SCR bridge.  The total conduction angle for the SCRs will be only a few degrees or conduction time will be ~0.1 ms.  Your timing and triggering circuit probably does not have that much resolution.

Lynn