Engine fuel injection frequency control method and system and automobile

Abstract

The invention discloses an engine fuel injection frequency control method and system and an automobile, and relates to the technical field of engine control. The method comprises the steps that the target fuel injection quantity, the fuel density, the maximum injection oil pressure, the static injection flow, the static fuel density, the static injection oil pressure, the maximum injection angle,the minimum injection interval time and the engine rotating speed are obtained, and a first maximum injection frequency is calculated; the single-cycle fuel injection quantity injected into an air cylinder at a next moment and the actual fuel rail pressure are obtained, and a second maximum injection frequency is calculated; the working conditions of an engine are recognized, and a third maximum injection frequency is obtained according to the engine rotating speed, the single-cycle fuel injection quantity and an injection frequency mapping table of injection manners corresponding to the working conditions of the engine; and a final injection frequency is determined according to the first maximum injection frequency, the second maximum injection frequency and the third maximum injection frequency. Different injection frequencies are designed on the basis of different design objectives under different engine working conditions, so that the purposes of improving exhaust temperature, reducing emissions and improving the fuel economy are achieved, and the influence of injection on adjacent injection pulse widths is avoided.

Description

technical field [0001] The invention relates to the technical field of engine control, in particular to an engine fuel injection frequency control method, system and automobile. Background technique [0002] The engine mainly converts the chemical energy of fuel into mechanical energy to realize power output and provide power for the whole vehicle. The fuel system of the engine is mainly to provide fuel to the engine to mix with air to form a combustible mixture according to the needs of the engine's operating conditions. In order to reduce engine vibration and noise, improve engine cold start or emission performance, it is required to set different injection times according to different engine operating conditions. The current common injection times setting is determined by signals such as engine speed, fuel injection volume, battery voltage, and water temperature. However, the working conditions of the engine are complex, and the number of fuel injections is related to m...

AI Technical Summary

Problems solved by technology

However, the working conditions of the engine are complicated, and the number of fuel injections is related to multiple working parameters. Judging only based on signals such as engine speed, fuel injection volume, battery voltage, and water temperature is not applicable in some working conditions.

Images