A self-learning method for gasoline engine long-term fuel correction

Abstract

The invention relates to the technical field of engine control, in particular to a self-learning method for gasoline engine long-term fuel correction. Judging whether the self-learning working condition judgment condition is met, if so, enter the self-learning working condition stabilization stage; judge whether the self-learning stabilization stage is over, if it is over, enter the self-learning storage activation judgment stage; according to the engine speed in the T2 time period mean n Avg , load average rho Avg , short-term fuel trim average value STFT Avg Calculate the speed load (n Avg , rho Avg ) to the last updated long-term fuel trim value r Bef ; combined with STFT Avg Calculate the long-term fuel correction value r′ under the current speed load (A,a) 1 , the long-term fuel correction value r′ under the current speed load (A,b) 2 , the long-term fuel correction value r′ under the current speed load (B, a) 3 and the long-term fuel correction value r′ under the current speed load (B,b) 4 . Carry out self-learning according to real-time working conditions, and read the average value of fuel correction for a period of time as the input of long-term fuel correction, so that the updated long-term fuel correction value has higher accuracy.

Description

technical field [0001] The invention relates to the technical field of engine control, in particular to a self-learning method for gasoline engine long-term fuel correction. Background technique [0002] The short-term fuel correction is a real-time correction control of the fuel injection quantity based on the rich and lean mixture in the previous working cycle fed back by the oxygen sensor. The change of the long-term fuel correction coefficient is a qualitative change formed on the basis of the quantitative change of the short-term fuel correction feedback result by the electronic control unit. [0003] The accuracy control of the long-term fuel correction coefficient is particularly important. The long-term fuel correction plays an important role in the fuel closed-loop control process, which can compensate for oil product differences and engine manufacturing differences. However, as the working conditions of the engine change continuously, and even as the engine wears ...

AI Technical Summary

Problems solved by technology

It can perform long-term fuel correction according to real-time working conditions to ensure the accuracy of long-term fuel correction coefficients, realize precise control of fuel injection volume, and solve problems such as economy and emissions

Images