Transient fuel control method, device and vehicle for in-cylinder direct injection gasoline engine

Abstract

The invention discloses a transient fuel control method, device and vehicle for an in-cylinder direct injection gasoline engine. The method includes: when a transient fuel activation condition is reached, acquiring transient oil film parameter information and an actual air-fuel ratio; , obtain the actual required fuel quantity in the cylinder; in the initial sampling period, according to the transient oil film parameter information and the actual required fuel quantity in the cylinder, obtain the oil film to calculate the initial value of the fuel injection quantity; calculate the fuel injection quantity according to the transient oil film parameter information and the oil film The initial value, obtain the oil film amount of the transient oil film; according to the oil film amount and the actual fuel demand in the cylinder, obtain the transient oil film compensation coefficient and the oil film to calculate the fuel injection amount; adjust the air-fuel ratio through the transient oil film compensation coefficient, according to the adjustment The fuel injection amount in the cylinder is calculated based on the subsequent air-fuel ratio, and the fuel injection control is performed. The present invention can realize precise control of the transient air-fuel ratio, improve the combustion efficiency in the transient condition, and effectively improve the emission in the transient condition.

Description

technical field [0001] The invention relates to the field of automobile fuel control, in particular to a method, a device and a vehicle for transient fuel control of an in-cylinder direct injection gasoline engine. Background technique [0002] Compared with traditional port injection, in-cylinder direct injection technology can effectively reduce in-cylinder temperature, improve charging efficiency, and reduce knocking tendency; a larger compression ratio can be used to improve torque and fuel economy. The mainstream of automobile development. The direct injection gasoline engine in the cylinder mainly uses the high-pressure fuel pump to output high-pressure fuel. After the fuel is distributed, the fuel injector directly injects the fuel into the combustion chamber at the appropriate time. However, for the direct injection gasoline engine in the cylinder, under the transient condition, the oil mist will also be directly injected onto the low temperature cylinder wall or pi...

AI Technical Summary

Problems solved by technology

For mechanical structural adjustment, such as the authorized patent announcement number CN204591511U discloses a piston structure for direct-injection gasoline engines. In transient working conditions, oil jets are likely to be sprayed onto the cylinder wall, and this device cannot effectively avoid it. In addition, the complex piston top design also increases the cost of processing; another authorized patent No. CN202937361U discloses a new type of in-cylinder direct injection combustion system. Stress concentration is formed at the groove, which will cause the risk of fatigue cracks on the top of the piston for a long time. In addition, the complex design of the top of the piston also increases the cost of processing; another US patent No. US7104250B1, the patent name is Injection spray pattern for direct injectionspark ignition engines , the problem of fuel wet wall can be effectively improved by adjusting the angle of ignition injection and fuel injection. Due to the complexity of gasoline engine fuel control, the problem of wet wall cannot be completely avoided, and wet wall problem will also appear in transient conditions.

Images