A fuel injection control method for a vehicle equipped with a direct injection engine

Abstract

The invention relates to the technical field of automobile control, in particular to a fuel injection control method for a vehicle equipped with a direct injection engine. The fuel injection activation conditions include the activation conditions based on fuel rail fuel pressure and the activation conditions based on the number of engine operating cycles. Fuel injection is allowed only when the two activation conditions are met at the same time; the activation conditions based on fuel rail fuel pressure refer to the current fuel rail pressure value Greater than the minimum fuel rail fuel pressure determined based on the current engine water temperature and the ambient atmospheric pressure of the engine; the activation condition based on the number of engine operating cycles means that the actual number of engine operating cycles is greater than the minimum number of engine operating cycles determined based on the current engine water temperature. The present invention fully considers the control method of various factors affecting the fuel atomization effect, takes into account the influence of water temperature, atmospheric pressure and engine operation cycle times on the fuel atomization effect, and selects the most reasonable fuel injection control scheme to achieve Optimum spray effect.

Description

technical field [0001] The invention relates to the technical field of automobile control, in particular to a fuel injection control method for a vehicle equipped with a direct injection engine. Background technique [0002] For direct-injection engines, since the fuel is directly injected into the cylinder, a certain oil pressure is required to ensure a good result of fuel-gas mixing and atomization, but too high oil pressure will not only cause power loss and The solenoid valve consumes electricity, and it is also possible that the high-pressure fuel injection to the cylinder wall may easily cause the gas mixture in the cylinder to be locally thick and thin. [0003] Therefore, the fuel injection activation of the direct injection engine needs to be carried out under a certain oil pressure to improve the atomization effect. Patent No. "CN201110457568.2" Chinese invention patent titled "In-Cylinder Direct Injection Gasoline Engine High-Pressure Start Control Method" disclo...

AI Technical Summary

Problems solved by technology

The existing problems are: the starting water temperature in this scheme is only used as a judgment condition for high-pressure starting or low-pressure starting, and the fuel pressure in actual operation does not take the starting water temperature as a reference factor, but due to the fuel atomization effect during the starting process should be It is different at different water temperatures. The setting of the starting oil pressure should be based on the current actual water temperature, and the effect is better. In addition, this scheme does not consider the air pressure.

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