Basic Principles of Common Rail Electronic Control Fuel Injection Technology for Diesel Engines

The electronic fuel injection technology has developed from the initial position control type to the time control type, and the common rail electronic fuel injection technology belongs to the latter. The common rail electronic control system uses various relevant sensors to collect and transmit the operating status parameters of the diesel engine to the controller (ECU). The ECU calculates the injection quantity, injection pressure, injection timing, and injection rate based on the target setting values, and then sends commands to the actuator to drive its action, allowing the diesel engine to operate at its optimal state< Br/>

The common rail electronically controlled injection technology refers to a fuel supply method that completely separates the generation of injection pressure and the injection process in a closed-loop system composed of a high-pressure oil pump, pressure sensor, and electronic control unit (BCU). It is transported by a high-pressure fuel pump to a common fuel supply pipe, and precise control is achieved through the oil pressure inside the common fuel supply pipe, so that the pressure of the high-pressure fuel pipe is independent of the engine speed. This can greatly reduce the degree of change in diesel engine fuel supply pressure with engine speed, thereby reducing the defects of traditional diesel engines. The ECU controls the amount of fuel injected by the fuel injector, which depends on the fuel rail pressure and the duration of the solenoid valve opening.

This technology no longer adopts the traditional principle of plunger pump pulsation fuel supply, but directly or indirectly forms a constant high-pressure fuel through the common rail, which is distributed to each fuel injector. With the help of the high-speed electromagnetic on-off valve integrated on each fuel injector, the fuel quantity injected into the diesel engine combustion chamber is controlled in a fixed and quantitative manner, ensuring that the diesel engine achieves the best combustion ratio, good atomization, and optimal ignition time Sufficient energy and minimal pollution emissions.

The common rail electronic fuel injection technology of diesel engines combines computer control technology, modern sensing and detection technology, and advanced fuel injector structure. It can not only achieve high injection pressure, achieve control of injection pressure and quantity, but also achieve pre injection and post injection, thereby optimizing fuel injection characteristics, reducing diesel engine noise, and greatly reducing exhaust emissions.