Разработване на система за впръскване на гориво за дизелов двигател

1. Основни етапи на разработка на дизеловата система за впръскване на гориво на двигателя
Since Diesel engine was invented by Diesel in 1892, due to the limitation of technology at that time, no suitable fuel supply system has been found. There was no substantial progress in the next 30 years.In order to solve the problem of fuel supply, Bosch Company developed an in-line synthetic pump for diesel engines in the late 1920s. As a result, the technology of diesel engine is developing rapidly, and diesel engine is becoming more and more popular in people's production and life.However, after the 1970s, the oil crisis and the diesel engine emission pollution incident.The further development of diesel engine technology is facing both new development opportunities and new challenges [4-6].The development of diesel engine Системата за впръскване на гориво премина през четири етапа:
(1) От 1892 до 1927 г. ранните дизелови двигатели използват система за впръскване на въздух, в която 7 MPa сгъстен въздух се използва за издухване на гориво в цилиндъра .
(2) From 1927 to 1970, the diesel engine adopted mechanical injection system, which was mainly composed of mechanical injection pump and injector.Due to the low control accuracy of mechanical speed governor and mechanical fuel injection advance, the response is not sensitive.Although these mechanical devices also realize the control of the main parameters that affect the economy and emission of diesel Двигателите, обаче, контролният ефект все още не е задоволителен . Следователно традиционният механизъм за механично управление е трудно да се отговори на изискванията за по-нататъшно подобряване на производителността и намаляване на емисиите на дизелови двигатели ., дори ако е допълнително сложно, е трудно или дори невъзможно да реализира контрола на високата точност .
(3) From 1970 to 1995, the conventional electronic control fuel injection system appeared, which is characterized by high control accuracy and large control freedom.The control function is complete,The injection characteristics (injection pressure, injection quantity, injection timing and injection rate) of the fuel injection system can be changed with the working conditions of the diesel engineThe state optimization greatly reduces the harmful emissions of the diesel engine и подобрява икономиката си .

(4) Since 1995, a brand new fuel injection system, electronically controlled common rail fuel injection system, has been developed as shown in Figure 1.1. It is characterized in that the actual running state of the diesel engine can be detected by a sensor, After data processing, the injection time, injection rate and injection quantity are optimally controlled by corresponding actuators.Meanwhile, the pressure in the common rail pipe is контролиран чрез регулиране на количеството на горивото, влизащо в общата релсова тръба .

Фигура 1 Електронно контролирана система за впръскване на обикновена релса

2. Разработване на електронно контролирана система за впръскване на гориво за дизелов двигател
Въведени са три поколения чуждестранни дизелови двигатели електронно контролирани системи за впръскване на гориво, както е показано в таблица 1.1.
Таблица 1 Развитие на електронната система за впръскване на гориво на чужд дизелов двигател

Фигура 2 Развитие на помпа за впръскване на гориво

From the development of the 1970s to the practical use of the 1980s, the electronic fuel injection system based on position control belongs to the first generation of products.It only needs to replace the original mechanical plunger pump with an electric control pump and its control components to become an electric control system.The structure of the diesel engine hardly needs to be changed, so that the control precision and the response speed are improved, the Производственото наследство е добро, обаче, гъвкавостта на контрола и преходния контрол на контрола не са достатъчно идеални и скоростта на налягане в инжектиране и скоростта на инжектиране не могат да бъдат ефективно контролирани . По -зрелите продукти са: ① Подобряване въз основа на дистрибуционната помпа ., например, системата EDCCOVEC в Bosch Company in Germany and IN Приложете контрол на позицията на помпата ., като Copec System и TICS система на Zexel Company в Япония .

Характеристики на тези продукти:
① или положението на багажника или плъзгащия се втулва се контролира от пропорционален електромагнит или двигател с директен ток, а сензорът за позиция се използва като сигнал за обратна връзка, реализирайки контрола на количеството на впръскване на горивото;
② ИЛИ Оригиналният напредък в инжектирането на гориво е подобрен и се приема електрохидравличен серво механизъм за контрол на позицията на бутало на горивния инжектор, осъзнайте контрола на времето за впръскване на горивото .

In the 1990s, The second generation of electronic control injection system with time control and the third generation of electronic control injection system with pressure and time control appeared one after another. The time-controlled injection system changes some mechanical structures of the conventional injection system, The characteristic that the plunger pump can bear high pressure is utilized to provide high oil supply pressure, The oil injection start point and oil injection quantity are directly controlled by using a Високоскоростен и мощен електромагнитен клапан за преливане, който има предимствата на директното управление и бързата реакция ., той може да достигне много високо налягане на инжектиране, но не може да реализира гъвкава регулиране на налягането на инжектиране и гъвкав контрол на инжекционната скорост .

Типичните системи за инжектиране на инжектиране във времето включват системата за разпределение на модел 1 на Zexel Company в Япония и ECD на Denso Company в JapanV3 System Pump System, DS и RS дистрибуторска помпа на компанията Stanadyne в Съединените щати, DDEC системата на Detroit Company в Съединените щати и ЕС на Lucas Company в Обединената система на Kingdomi, etct .

Compared with the position control system and the time control system,The pressure-time control type electronic control injection system completely gets rid of the original system structure of an injection pump,The computer control technology, the modern sensing detection technology and the high speed solenoid valve technology are integrated into the advanced fuel injection mechanismA brand new electronically controlled injection system,The start and stop of the injection of the fuel injector can be controlled by the solenoid valve: the injection timing is determined by the action time of the solenoid valve,The amount of fuel injection is determined by the duration of action and the common rail pressure. It is different from the traditional plunger pump which adopts the principle of separate cylinder pulsation oil supply.The new electronically controlled injection system adopts the pressure-time fuel metering principle.The oil injection control is realized by combining the continuous control of the oil pressure of the common oil duct and the electromagnetic valve control of the injection process of each cylinder,Therefore, it is called pressure-time control electronic control injection system, also known as electronic control common rail injection system.The system can not only control the fuel injection quantity and the fuel injection timing in time,But also can control the injection pressure and the injection rate which can not be controlled in the past,The℃of freedom and control precision of the system have been greatly improved.Common rail injection system can be divided into medium pressure common rail injection system and high pressure common rail injection system.The basic principle of fuel injection control of the two systems is the same, but the structure of the fuel injector is different.Pressure amplification is added in the injector of medium pressure common rail injection system, and the structure is complex.Typical examples are HEUI system developed by Caterpillar Company in the United States and Servojet system developed by BKM Company in the United States.In the case of high-pressure common rail injection systems,Nippondenso has developed the ECDU2 high pressure common rail injection system (shown in Figure 1.2) for medium duty diesel Двигателите . След успешно съвпадение с дизеловия двигател на Hino J08C, той беше успешно съчетан с дизеловия двигател на ISUZU HK Series . До 2001 г. в рамките на 2001 г. ще достигне повече от 2000 набори; Извън ALFA 156. През 2003 г. Fiat успешно разработи второто поколение JTD 16- клапан с множество инжекционни дизелови двигатели; първото поколение на общата система за инжектиране на високо налягане, разработена от Bosch Company в Германия Стандарти за емисии Euro IV.

At present, Bosch, Germany, is directly applying the technology of coaxial variable nozzle and pressure amplifier to the development of high-pressure common rail injection system. It is believed that the high-pressure common rail injection system with a maximum injection pressure of more than 200 MPa will become a practical product in the near future. In addition, the CR system developed by Bosch on the basis of Fiat's Unijet system is mainly used in cars. After successfully matching with the products of BENZ, VW, BMW and other companies, the annual output of CR system is more than 1 million units. And developed a series of products from low power to medium power. In addition, Lucas Company in the United Kingdom and Stanadyne Company in the United States have also developed their own high-pressure common Железопътни електронно контролирани системи за инжектиране .