Method for realizing accurate equipower torque characteristics

Abstract

The invention discloses a method for realizing accurate equipower torque characteristics. On the premise of ensuring that the maximum explosion pressure and the thermal load of a diesel engine are in an allowed range, the accurate equipower torque characteristic with the torque adaptive coefficient and the rotating speed adaptive coefficient of larger than 2.5 of the diesel engine is realized by adopting technical approaches of a Hyperbrid boosting system, various cycle modes of Miller cycle / symmetrical cycle, 2 / 4 stroke cycle and other cycle modes, a pressure and flow stepless adjustable air management system, and the like. The technical scheme of the invention can expand the rotating speed and torque adaptive coefficient of the diesel engine, especially rotating speed adaptive coefficient, ensure that the rotating speed adaptive coefficient is easier to meet the requirement of a vehicle, simplify a drive device, improve the compactness of the whole power drive device of the vehicle, reduce the gear shifting operation of the vehicle and improve the efficiency of the whole system.

Description

technical field [0001] The invention relates to the technical field of turbocharged diesel engines, in particular to a method for realizing quasi-equal power torque characteristics. Background technique [0002] Generally, the torque adaptability coefficient of a highly enhanced supercharged diesel engine is less than 1.2, and the speed adaptability coefficient is less than 1.6. In order to adapt to different road conditions, the vehicle requires the maximum traction force to be more than 10 times the minimum traction force, and the maximum speed to be more than 10 times the minimum speed. Obviously, there is a large gap between the available torque and speed variation range of highly enhanced diesel engines and the vehicle demand, and a speed change device must be equipped to expand the variation range of the diesel engine's speed and effective torque, thereby reducing The volume power index of the power transmission system is increased, and the complexity of power transmi...

AI Technical Summary

Problems solved by technology

[0004] This kind of technical solution for matching the supercharger with the diesel engine at low speed can generally achieve the torque characteristic of constant power near the maximum speed of the diesel engine, but it is difficult to realize the characteristic of constant power in the middle and low speed range due to the limitation of the maximum explosion pressure of the engine.

In addition, in order to achieve equal power characteristics, the method of reducing the fuel injection volume in the high-speed section is generally used in conjunction with the low-speed matching of the supercharging system, which will lose the effective displacement of the diesel engine and cannot adapt to the development trend of future vehicle diesel engine miniaturization.

[0005] Moreover, the technical scheme of matching the diesel engine with the turbocharger by using the exhaust gas at the high-speed section loses the energy of the exhaust gas of the diesel engine, reduces the recovery of the energy of the exhaust gas, and reduces the efficiency of the diesel engine.

[0006] At the same time, the complex adjustable technology is used to realize the technical scheme of matching the diesel engine and the supercharger. The structure is relatively complicated, and the adjustment ability of the adjustable supercharging technology is limited, so it is difficult to realize the torque characteristics of equal power.

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