Working Principle of EFI Diesel Generator Set

With the attention paid to environmental protection, the EFI diesel generator set has become the first priority when you choose the standby power supply because of its energy saving, fuel saving and environmental protection characteristics. In this article, Starlight Power Generation Equipment will show you the principle and characteristics of the EFI diesel generator set.

Principle of EFI diesel generator set:

The fuel is extracted from the fuel tank by the gear pump driven by the engine camshaft through the filter and flows to the fuel supply pump through an electromagnetic emergency shutdown valve. At this time, the pressure is about 0.5MPa, and then the oil flow is divided into two ways. One way flows into the pressure control valve through the small hole on the safety valve as cooling oil through the camshaft chamber of the oil supply pump, and then flows back to the oil tank. The other way is filled with the 3-cylinder fuel supply pump. In the fuel supply pump, the fuel pressure rises to 135MPa or higher and is supplied to the common rail. The common rail has a pressure sensor and a pressure control valve that controls the flow by cutting off the oil circuit. Use this method to adjust the common rail pressure set by the control unit. After the high-pressure fuel flows into the injector from the common rail, it is divided into two routes: one is directly injected into the combustion chamber, and the other is returned to the fuel tank together with the fuel leaked from the needle valve guide part and the control plunger during the injection.

The characteristics of the electronically controlled high-pressure common rail system can be summarized as follows:

1. Free adjustment of injection pressure (common rail pressure control)

The injection pressure is controlled by controlling the common rail pressure. Use the common rail pressure sensor to measure the fuel pressure, so as to adjust the fuel supply volume of the fuel supply pump and the common rail pressure. In addition, feedback control can also be carried out consistently according to the engine speed, fuel injection volume and the set optimal value (command value).

2. Free adjustment of fuel injection quantity

Based on the engine speed and throttle opening signal, the computer calculates the optimal fuel injection quantity and controls the power-on and power-off time of the fuel injector.

3. Free adjustment of injection rate shape

Set and control the injection rate shape according to the needs of the engine: pre-injection, post-injection, multi-stage injection, etc.

4. Free adjustment of injection time

According to the parameters such as engine speed and fuel injection quantity, the optimal fuel injection time is calculated, and the electronically controlled fuel injector is controlled to open and close at the appropriate time, so as to accurately control the fuel injection time.

In the electronically controlled common rail system, various sensors-engine speed sensor, throttle opening sensor, various temperature sensors, etc. - detect the actual running state of the engine in real time. After calculation by the microcomputer according to the pre-designed calculation program, the parameters such as the fuel injection quantity, the fuel injection blade spacing, the fuel injection rate model and so on suitable for the running state are determined, so that the engine can always work in the best state.

The computer has the self-diagnosis function to perform technical diagnosis on the main parts of the system. If a part fails, the diagnosis system will send an alarm to the driver and automatically handle it according to the fault situation; Or stop the engine - the so-called fault emergency function, or switch the control method to make the vehicle continue to drive to a safe place.

In the traditional pump nozzle fuel system, the injection pressure is related to the engine speed and load, not an independent variable.

In the high-pressure electronically controlled common rail system, the injection pressure (common rail pressure) is independent of the engine speed and load, and can be controlled independently. The fuel pressure is measured by the common rail pressure sensor and compared with the set target fuel pressure for feedback control.

Starlight Power was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. If you want get more information, please feel free to send email to sales@dieselgeneratortech.com we will pay highly attention on your question.