I've designed undervoltage cutoff with cutoff voltage of 52.8v and 57.8v on voltage, TL431 doesn't like such high voltages so I put a 30v zener diode D1 in series with it, R6 resistor is drawing some current through that diode so it keeps voltage drop when TL431 is off, I'm not really sure how much current I should set here to be safe.
This needs to turn on a load with 10mF input capacitance, so when TL431 turns on Q1 BC640, four IRF740 Mosfets driven by R7-R8 divider are charging that capacitance through R10-R13 resistors, then 30-40ms later when capacitors are mostly charged, Q2 IRF2807Z driven by R9-C1 starts turning on, (D2 is to make it turn off faster), I chosed IRF740 because they can take quite large single pulse for the price, maybe IRF540 would make here more sense but I can't buy it, everywhere are IRF540N which as it turns out are garbage in terms of single pulse capability (for 10ms at 20v only 4.5A, "old" IRF540 can take 20A), maybe there is some other mosfet of similar price that is good at this, maybe something that can replace all 4 IRF740?
What do you think of this circuit, do you have any ideas for improving it?