Gas machine, control method and device and gas machine system

The invention relates to a gas machine, a control method and device and a gas machine system. The method comprises the steps that the current gas inlet pipe pressure and the engine rotating speed are obtained; a target air-fuel ratio corresponding to the current air inlet pipe pressure and the generator rotating speed is obtained; acquiring negative pressure of gas in a pipeline between an air filter and a mixer, and temperature and atmospheric pressure of gas in a pipeline between the mixer and a supercharger; according to the obtained negative pressure, the temperature, the atmospheric pressure and the target air-fuel ratio, a theoretical supercharger rotating speed is obtained by combining a corrected relation model of the preset supercharger rotating speed and the air-fuel ratio; according to the method, an oxygen sensor does not need to be arranged, and the defects caused by using the oxygen sensor are avoided. 本发明涉及一种气体机、控制方法及装置、气体机系统，该方法包括获取当前进气管压力和发动机转速；获取当前进气管压力和发电机转速对应的目标空燃比；获取空滤与混合器之间管路内气体的负压、混合器与增