Point taken. My bad. Sorry, GoGreen, ignore my circuit. Back to the drawing boardOn the circuit. FETs running in linear mode like this can't be paralleled with just a small source resistor like a BJT. The threshold voltage variation can be several volts and the gain and thermals don't like it. It looks ok in spice because the thresholds match, but if you put 2 or 3 diodes in series with one gate you can see the problem.
Edit:
Ronv makes a very valid comment that a linear regulator would need to be set below the minimum of the ripple (say 60V). So if you used one the existing dump load would never activate. In effect the regulator would become a new dump load since it would have to dissipate a large amount of power. For a load current of 14A and an input voltage of 130V the dissipation would be (130-60)*14 = 980W. Hence 2 x 300W FETs alone wouldn't cut the mustard. You would also need some hefty resistors to share the power dissipation.
As Ronv said, an SMPS would be a better bet.
Last edited: