Engine egr system and diagnostic strategies for engine egr system

Abstract

An engine EGR system and a diagnostic strategy for the engine EGR system, the engine EGR system includes: an EGR pipeline, an EGR cooler and an EGR valve are arranged on the EGR pipeline, and the intake end of the EGR valve is connected to the EGR cooler The outlet end of the pressure difference sensor, the inlet end of the pressure difference sensor can be selectively communicated with one of the first point and the second point on the EGR pipeline, and the first point is located at the EGR cooling The inlet end of the device, the second point is located between the outlet end of the EGR cooler and the inlet end of the EGR valve, the outlet end of the differential pressure sensor is connected to the EGR pipeline, and connected to The point is located at the gas outlet end of the EGR valve; the controller is connected in communication with the differential pressure sensor. The engine EGR system of the present invention can realize the blockage detection of the EGR cooler and the EGR valve, help to adjust the EGR rate accurately, and avoid engine deflagration and fuel consumption increase due to the problem of inaccurate EGR rate adjustment.

Description

technical field [0001] The invention relates to the technical field of engine manufacturing, in particular to an engine EGR system and a diagnostic strategy for the engine EGR system. Background technique [0002] Environmental issues, energy crisis, stringent emission and fuel consumption regulations have brought severe challenges to the internal combustion engine industry. Reducing fuel consumption and reducing emissions are the two core issues at present. [0003] Under the above background, various car companies and research institutes have proposed that the low-pressure EGR system be applied to gasoline engines, leading the exhaust gas from the catalytic converter to the front of the compressor, and introducing the cooled exhaust gas into the cylinder to reduce the temperature and ratio of the working fluid in the cylinder. The heat ratio can reduce the pumping loss of small and medium loads. After introducing EGR under heavy loads, it can reduce the compression end te...

AI Technical Summary

Problems solved by technology

[0005] EGR is composed of combustion exhaust gas, which is easy to condense and coke after being cooled by the cooler, which will block the EGR cooler and EGR valve

The blockage of the EGR pipeline will cause inaccurate EGR rate adjustment. Under the working condition of high load and high EGR rate, inaccurate EGR rate adjustment will easily cause serious knocking of the engine, and there is a risk of scrapping the engine.

[0006] In the related art, there is no relatively simple system and strategy for testing the blockage of the EGR cooler and EGR valve, and there is room for improvement

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