Hello,
I am designing an automatic voltage regulator (AVR) for a generator. Attached is the ISIS file and simulation of the circuit.

Problem: The full wave bridge rectifier works fine independently but gives zero output when connected to rest of circuit. The output of bridge should be 26V DC at capacitor C1. The output of AVR should be 70-80V DC accross diode D1.

Can you tell what is the problem in the bjt and mosfet circuit which is causing the bridge output go to zero.

Moreover, I couldn't find the ISIS model for bjt D882 so an alternative is used.

 

Give it a ground.

 

Ok, got it, Thanks

 

Yeah give it a ground because the second circuit after h bridge is unable to compare the voltage level. When the Ground will be common, they will act at same voltage level.