Delayed power-off control circuit and method for a fuel cell new energy bus

The invention discloses a delayed power-off control circuit for a fuel cell new energy passenger car, the circuit is connected with a vehicle controller, and the vehicle controller outputs the delayedpower-off signal by detecting the normal power-off signal of each component of the vehicle. The delay power-off control circuit comprises the following units: a first low-voltage power supply unit and a second low-voltage power supply unit, wherein the first low-voltage power supply unit and the second low-voltage power supply unit provide a low-voltage power supply for a vehicle through the control of a low-voltage power supply feedback signal; A delayed power-off control unit that controls the on-off of the first gear power signal, outputs a low-voltage power feedback signal according to the status of the received delayed power-off signal, and realizes the delayed power-off of the vehicle; An entire vehicle controller power supply control unit that provides a dual power supply controlled by a first gear power s