Diesel generator set is a type of ac power supply equipment of self-owned power station. It is a small and independent power generation equipment, powered by internal combustion engine and driven by synchronous alternator.

Modern diesel generator set consists of a diesel engine, three-phase ac brushless synchronous generator, control box (screen), the cooling water tank, coupling, fuel tank, muffler, and components such as public base overall rigidity.Diesel engine flywheel shell to the front end cover of the generator axial convex shoulder positioning direct connection is adopted to form an organic whole, and USES the cylindrical elastic coupling by the rotation of the flywheel direct drive generators, its connection mode by the screw together, make the connection into a steel body, guarantee the concentricity of the crankshaft of diesel engine and the generator rotor within the prescribed scope.

Diesel generating set is made up of internal combustion engine and a combination of synchronous generators, internal combustion engine's maximum power limited by parts of synchronous generators, internal combustion engine's maximum power limited by parts of mechanical load and thermal load, known as the rated power, rated power of the ac synchronous generator is refers to under the rated speed, the long-term continuous operation, the output power rating, usually the diesel engine output power rating and synchronous alternator output power rating, referred to as the matching ratio.