Diesel engine sequential turbocharging structure

The utility model aims at providing a diesel engine sequential turbocharging structure comprising a diesel engine, an air inlet pipe, an air-exhausting pipe, a turbocharging device, a release valve, an air valve and a gas valve. The turbocharging device comprises a basic turbocharging device and a controlled turbocharging device, the air inlet pipe comprises an A-array air inlet pipe and a B-array air inlet pipe which are respectively connected with a compressor of the basic turbocharging device and a compressor of the controlled turbocharging device, the air-exhausting pipe comprises an A-array air-exhausting pipe and a B-array air-exhausting pipe which are respectively connected with a turbine of the basic turbocharging device and a turbine of the controlled turbocharging device, the A-array air-exhausting pipe is communicated with the B-array air-exhausting pipe through an air-exhausting communication pipe, the gas valve is arranged on the B-array air-exhausting pipe, the air valve and the release valve are installed on the B-array air inlet pipe, and the release valve is arranged between the air valve and the compressor of the controlled turbocharging device. The structure can avoid the phenomenon that the compressors have rotation speed but zero flow, eliminates surge phenomenon of the turbocharging device, and effectively improves use conditions of the turbocharging device.