Method for controlling oil injection of diesel engine

Abstract

The invention discloses a method for controlling the oil injection of a diesel engine, which is used for reducing tail-gas pollution. The method comprises the following steps: calculating a demanded injected oil amount by a control unit according to an air inflow measured by an air inlet sensor, calculating actual air inflow according to the engine displacement, the cylinder number of the engine,the volumetric efficiency of engine, the information of engine speed and the actual intake pressure which is measured by a boost pressure sensor in a pressurization system, obtaining calibration values by looking up a gauge according to the engine speed information and the engine gear information, and finally obtaining a maximum injected oil amount according to the actual air inflow and the calibration values, wherein the calibration values refer to a specific value of air inflow and injected oil amount of maximum torque (obtained through a pretest) of the engine under the condition that the engine is at a special gear and a special speed, and the tail gas is up to the standard; when the demanded injected oil amount is greater than the maximum injected oil amount, the control unit controls the actual injected oil amount according to the maximum injected oil amount, and when the demanded injected oil amount is less than or equal to the maximum injected oil amount, the control unit controls the actual injected oil amount according to the demanded injected oil amount.

Description

technical field [0001] The invention belongs to the technical field of automobile manufacturing, and in particular relates to a fuel injection control method of a diesel engine. Background technique [0002] When the air intake of diesel common rail engine is unreasonable, a large amount of soot will be produced, which will pollute the environment. At present, diesel vehicles calculate the fuel injection volume based on the measured air intake volume, so as to limit the smoke in the exhaust gas. When the intake booster pipeline of the diesel common rail engine falls off or the supercharger is abnormal, the actual intake air volume will decrease, but the intake sensor for measuring the air intake volume is generally arranged between the air filter and the booster Therefore, the intake sensor cannot detect the abnormality of the supercharger in real time, resulting in the failure of the smoke limit function of the control system, which cannot play a good limiting role. Cont...

AI Technical Summary

Problems solved by technology

[0002] When the air intake of diesel common rail engine is unreasonable, a large amount of soot will be produced, causing pollution to the environment

At present, diesel vehicles calculate the fuel injection volume based on the measured air intake volume, so as to limit the smoke in the exhaust gas

When the intake booster pipeline of the diesel common rail engine falls off or the supercharger is abnormal, the actual intake air volume will decrease, but the intake sensor for measuring the air intake volume is generally arranged between the air filter and the booster Therefore, the air intake sensor cannot detect the abnormality of the supercharger in real time, resulting in the failure of the smoke limit function of the control system, which cannot play a good limiting role

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