A type of diesel generator set is a self-supplied power plant AC power supply equipment is a small independent power generation equipment, powered by internal combustion engines, and drives simultaneous AC generators. Modern diesel generator set consists of diesel engine, three-phase AC brushless synchronous generator, control box (screen), heat dissipation tank, coupling, fuel tank, muffler, and common base, etc. The axial direction of the diesel engine is integrated with the axial direction of the front end cover of the generator, and the cylindrical elastic coupling is used by the flywheel directly drives the rotation of the generator, and the coupling method is fixed by the screw, so that two The couples are coupled into a steel body to ensure that the crankshaft of the diesel engine and the concentricity of the generator rotor are within the prescribed range. The diesel generator set is combined by the internal combustion engine and the synchronous generator, and the power of the internal combustion engine is limited by the mechanical load and heat load of the components, called rated.