Start-up control method of diesel engine in cold environment

Abstract

The invention relates to the field of vehicle start control, in particular to a cold start control method for a vehicle in the severe cold environment. The start control method in the diesel engine cold machine environment comprises the steps that if the condition that the initial water temperature of an engine is lower than the water temperature threshold value of the engine and the condition that the rotation speed rising speed of the engine is lower than the rotation speed acceleration threshold value are met at the same time, cold start control is enabled; the cold start control comprises database building, wherein in a database, the fuel injection advance angle maximum value, the engine rail pressure maximum value and fuel injection quantity maximum value are set with the engine initial water temperature as an index; and control over the current fuel injection advance angle, the current engine rail pressure and the current fuel injection quantity is conducted before start is completed. According to the start control method in the diesel engine cold machine environment, the fuel injection advance angle, the engine rail pressure and the fuel injection quantity are gradually increased with the rotation speed acceleration as the threshold value, the problems of resonance of dual-mass flywheels and difficult start are solved, and the parameters are fed back and corrected after start is successful, the optimal start effect is achieved, and the start performance of the diesel engine vehicle in the severe cold environment is improved.

Description

technical field [0001] The invention relates to the field of vehicle start control, in particular to a vehicle cold start control method in a severe cold environment. Background technique [0002] In the prior art, when the vehicle is in a cold environment, most of them are based on correcting the fuel injection quantity to shorten the start-up time and improve the start-up reliability; this correction method does not consider the actual situation of the vehicle; at present, the dual-mass flywheel It is widely used in manual transmission models. It has a very significant effect on the optimization of the torsional vibration of the transmission system and the smoothness of shifting during driving, and improves the comfort and driving performance of the vehicle as a whole. However, the negative effect of the dual-mass flywheel is that its characteristics cause the engine speed to exist in a resonance region between 300-600rpm. This is an area that cannot be avoided during eng...

AI Technical Summary

Problems solved by technology

However, under extremely low temperature conditions, the in-cylinder combustion stability and efficiency of the diesel engine will be reduced, and the speed of the engine's speed increase will be relatively significantly worse when the engine is started.

In turn, the common engine speed is suspended in the resonance area and cannot continue to rise, resulting in longer cold start time at low temperature or failure to start, and also causing damage to the dual-mass flywheel

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