Natural gas engine fuel gas control system and method and vehicle

The invention provides a natural gas engine fuel gas control system and method and a vehicle. The natural gas engine fuel gas control system comprises a low-voltage electromagnetic control valve, a fuel gas inlet pipe, a fuel gas and air mixer and an ECU, wherein one end of the low-voltage electromagnetic control valve is connected to a whole vehicle air source, the other end of the low-voltage electromagnetic control valve communicates with a mixed gas cavity of the fuel gas and air mixer through a gas inlet pipe, the ECU accurately controls the supply amount of fuel gas sprayed into the mixer by a nozzle by reading data of a fuel gas temperature and pressure sensor in front of the nozzle, and due to the fact that no pipeline is arranged behind the nozzle, quick response can be achieved when a vehicle brakes or accelerates, a turbofan turbulent flow is arranged inside the mixer, and generated rotational flow can accelerate mixing of fuel gas and air, so that combustion is more sufficient, the economical effi