Quick reset high-voltage input power supply anti-surge circuit

The invention relates to a quick reset high-voltage input power supply anti-surge circuit, which comprises a main power circuit, a sampling judgment circuit and an isolation circuit, and is characterized in that the main power circuit is connected with the sampling judgment circuit and the isolation circuit, and the isolation circuit is connected with the sampling judgment circuit; the main power circuit comprises an input capacitor and a field-effect tube, input voltage charges the input capacitor through a current-limiting resistor and charges a capacitor of a gate pole of the field-effect tube through the other branch, and the charging time of the input capacitor and the charging time of the field-effect tube are matched; the sampling judgment circuit samples the voltage from the main power circuit and judges whether the voltage reaches a voltage reference or not, if the voltage is lower than the voltage reference, the isolation circuit is switched on, then the gate voltage of the field-effect tube of the