Engine control parameter adjustment method

Abstract

The invention discloses an engine control parameter adjustment method, which comprises the following steps of: detecting vehicle tail gas oxygen content by using a wide-band oxygen sensor, and outputting an analog voltage signal; correspondingly compensating tail gas oxygen content sampling voltage obtained by sampling the analog voltage signal according to the change of reference level, and converting into a compensated current scalar; converting a plurality of compensated current scalars obtained according to a plurality of continuous tail gas oxygen content sampling voltages into corresponding current true values; looking up a table to obtain air excess coefficients corresponding to the current true values; and analyzing and evaluating by using a vehicle tail gas oxygen content analyzer according to the air excess coefficients to obtain target data for adjusting engine control parameters, and providing the target data to an engine control unit to adjust the engine control parameters. Through the engine control parameter adjustment method, the engine control parameters can be accurately adjusted, the amount of computation is small, the hardware requirement is low and the cost islow.

Description

technical field [0001] The invention relates to automobile technology, in particular to a method for adjusting engine control parameters. Background technique [0002] The widespread use of automobiles has led to more and more serious environmental pollution. For this reason, countries around the world have formulated strict emission standards to reduce harmful gas emissions. At the same time, a large amount of energy is wasted by low-efficiency engines, especially in today's increasingly tense oil resources, which has become an urgent problem to be solved. How to make cars reduce pollution and improve fuel efficiency has become the focus of the automotive industry. All major automakers have devoted great efforts to research and development to achieve the above-mentioned goals. [0003] One of the characteristics of oxygen ions is that it is easy to move at high temperature. The wide-area oxygen sensor based on this characteristic is usually sintered into a tube with zirco...

AI Technical Summary

Problems solved by technology

When the actual air-fuel ratio is within the theoretical air-fuel ratio, that is, between 0.9 and 1.1, the control accuracy requirement suddenly rises to 3‰, which requires that the air excess coefficient λ used for analysis and evaluation of the exhaust gas oxygen content analyzer has a high enough accuracy , but the analog voltage signal output by the wide-area oxygen sensor is converted with the reference voltage setting of the 5V wide-area oxygen sensor. After the voltage signal is processed, the fluctuation of the air excess coefficient λ of the nominal automobile exhaust oxygen content will exceed 3‰, which is difficult to meet the accuracy requirements of the air excess coefficient λ for the analysis and evaluation of the vehicle exhaust oxygen content analyzer, and the engine control parameters cannot be obtained High-precision target data for adjustment

[0005] In order to meet the high-precision requirements for the air excess coefficient λ, the existing vehicle exhaust oxygen content analyzer processes the analog voltage signal output by the wide-area oxygen sensor to obtain a high-precision air excess coefficient λ method, usually for the output of the wide-area oxygen sensor The analog voltage signal adopts fluid mechanics combined with combustion analysis, and through a series of complex data array algorithms, the high-precision air excess coefficient λ is obtained, which makes the hardware structure quite complicated and the manufacturing cost remains high

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