The composition of the electronic control device of the common rail fuel injection system
The electronic control device of the diesel engine using the common rail fuel injection system is divided into 3 subsystems:
- The sensor and the rated value transmitter for collecting the operating status and rated value, which convert various physical parameters into electrical signals.
- ECU is used to process information according to a certain mathematical calculation process (adjustment algorithm) and send out instruction electrical signals.
- The actuator is used to convert the command electrical signal output by the ECU into mechanical parameters
The control part and sensor part of the common rail fuel injection system include: ECU, crankshaft speed sensor, camshaft phase sensor, accelerator pedal sensor, boost pressure sensor, air mass flow meter, common rail pressure sensor and cooling water temperature sensor.
- The ECU knows the driver's request (accelerator pedal position) and the real-time working status of the diesel engine and the vehicle by means of sensors. It processes the signal generated by the sensor and input through the data wire, and controls and regulates the diesel engine.
- The crankshaft speed sensor measures the speed of the diesel engine
- The camshaft phase sensor determines the firing sequence and phase.
- The accelerator pedal sensor is a potentiometer, which informs the ECU about the driver's torque requirement through a voltage signal.
- The air mass flowmeter informs the ECU of the real-time intake air mass flow of the diesel engine to match the corresponding basic fuel injection quantity according to the requirements of emission regulations.
- The boost pressure sensor is used to measure the boost pressure (on a boost diesel engine with boost pressure adjustment)
- Cooling water temperature sensor and intake air temperature sensor are at low temperature and when the diesel engine is in a cold state, the ECU can determine the appropriate fuel injection starting point, pre-injection fuel quantity and other parameters according to the signal values of the cooling water temperature sensor and intake air temperature sensor The rated value of the parameter.