The application provides a
turbocharger, which belongs to the technical field of turbocharging technology and specifically relates to a
turbocharger, which comprises a compressor and a
turbine, the
impeller of the compressor and the
impeller of the
turbine are connected through a first rotating shaft, the compressor is arranged at the first end of the first rotating shaft, and the
turbine is arranged at the second end of the first rotating shaft; a boost turbine is arranged at one end of the compressor, the boost turbine has a second rotating shaft coaxial with the first rotating shaft, the second end of the second rotating shaft can be connected with the first end of the first rotating shaft; the boost turbine is driven by
compressed air, and the second rotating shaft of the boost turbine can drive the first rotating shaft to rotate together when the second rotating shaft rotates. The
turbocharger can start the boost turbine driven by
compressed air when the engine is in a low-speed working condition, the boost turbine is used to improve the rotating speed of the turbocharger, and thus the low-speed performance of the engine is improved. The application further provides an engine and a power
system of the turbocharger, and the reliability and safety are high.