| 摘要 |
The present invention relates to a pilot fuel injection correcting method of a diesel engine and a system thereof for correcting an error of a pilot fuel injection amount according to a change of operating characteristics of an injector for spraying a fuel in a diesel engine. According to an embodiment of the present invention, a pilot fuel injection correction method of a diesel engine comprises: a step for judging whether a mileage of a vehicle is over a predetermined mileage or not; a step for judging an overrun state that a diesel engine does not spray a fuel in case the mileage of a vehicle is over a predetermined mileage; a step for spraying a fuel in a setting condition corresponding to a setting reference heat generating amount, in case the diesel engine is in an overrun state; a step for detecting a combustion pressure by a fuel sprayed in the setting condition; a step for producing a heat generating amount based on the detected combustion pressure; a step for storing a heat generating difference as a pilot fuel spray correction value by producing the heat generating difference value by comparing the produced heat generating amount and the reference heat generating amount; and a step for spraying a pilot fuel by correcting the fuel spraying time, a spraying pressure, and a spraying amount based on the pilot fuel spray correction value. [Reference numerals] (AA) START;(BB,DD) NO;(CC,EE) YES;(FF) END;(S110) Vehicle mileage >= Predetermined mileage ?;(S120) Overrun state that a fuel is not sprayed ?;(S130) Spray a fuel in a condition corresponding to a reference heat generating amount;(S140) Detect a combustion pressure by a combustion pressure sensor;(S150) Calculate a combustion heat generation amount based on the detected combustion pressure (Use Ideal gas law and Law of thermodynamics);(S160) Calculate a heat generation difference value by comparing the calculated heat generation amount and a reference heat generation amount;(S170) Calculate, and store a fuel spray correction value based on a heat generation difference value;(S180) Spray a fuel by correcting a fuel spray time, a spray pressure, and a spay amount based on a fuel spraycorrection value, when a diesel engine is operated normally |
