Short circuit and overvoltage protection circuit for large current regulated power supply

The protection circuit is inside the dotted box .
    When the output is short-circuited , the transistor VTz is turned on, VTi is turned off, and the thyristor V
is turned on after a short delay (due to the action of the capacitor Cl), causing VT4 to VT7 to turn off one after another, cutting off the load circuit. When the output is over-voltage (the over-voltage setting value
is determined by the potential), V is turned on.
    To restore circuit operation, you can cut off the power supply and turn it on again after eliminating the fault, or insert a reset button in the thyristor anode circuit
.