Calibration method of engine intake correction map table and intake correction method

Abstract

The invention discloses a method for calibrating an engine air intake correction map table, which belongs to the technical field of engine intake air correction, and mainly solves the technical problem that the difference in intake manifold pressure affects engine performance and emission. The correction map table is passed as follows Steps to calibrate: S1. Install the engine on the test bench; S2. Obtain the upper limit, lower limit, and median value of the intake manifold pressure; S3. Calibrate the base fuel injection timing and base EGR corresponding to the median value Flow rate, basic urea injection volume; S4. Upper limit fuel injection timing, upper limit EGR flow rate, and upper limit urea injection amount corresponding to the upper limit value of the calibration; S5. Lower limit fuel injection timing, lower limit EGR flow rate, and lower limit urea injection rate corresponding to the lower limit value of the calibration value Injection volume. The invention also discloses an engine air intake correction method. The present invention can automatically correct fuel injection timing, urea injection quantity and EGR flow rate according to intake manifold pressure.

Description

technical field [0001] The invention relates to the technical field of engine air intake correction, more specifically, it relates to a calibration method of an engine intake air correction map table and an air intake correction method. Background technique [0002] With increasingly stringent emission and fuel consumption regulations and higher power densities, boundary conditions are often close to development limits. Engine development is carried out under a standard environment and model. Due to the limitation of development resources, the performance parameters of the engine only represent the situation of limited samples. However, once the engine is mass-produced, due to the differences in the consistency of engine components such as superchargers and EGR, the differences in the intake and exhaust pipelines and layouts of various vehicle manufacturers, and the differences in the intercooler system, the pressure of the engine intake manifold and the R&D There are large...

AI Technical Summary

Problems solved by technology

[0003] When the intake manifold pressure exceeds the limit value, due to the increase of intake pressure and intake flow, if there is no corresponding measure, the engine will exceed the burst pressure limit, especially at medium and high loads, resulting in an increase in engine mechanical load and risking reliability ;Turbocharger speed exceeds the limit value; NOx emissions increase, and the engine faces the risk of excessive emissions

[0004] When the intake manifold pressure is lower than the limit value, due to the reduction of intake pressure and intake flow, if there is no corresponding measure, the engine will exceed the exhaust temperature limit, especially at medium and high loads, resulting in an increase in engine heat load, and the reliability will be faced. Risks; risks such as increased smoke, poor fuel consumption, insufficient torque at low speed and large load, etc.

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