Study on the Control of Common Rail Fuel Pressure of Electronically Controlled Pressure Accumulation Fuel Injection System for Diesel Engines

In order to meet the demands of flexible control of fuel injection quantity and fuel injection pressure for electronically controlled pressure accumulation fuel injection system of diesel engines, it is necessary to control the common rail fuel pressure accurately and on real time. Here the electro-hydraulic proportional overflow valve was used as the the regulator of the common rail fuel pressure so as to control the common rail fuel pressure electronically. On the basis of the MC68HC11 single-chip microprocessor, the fuzzy PID controller of the common rail fuel pressure was developed and applied to controlling the fuel pressure in the common rail so that the close-loop control of the fuel pressure in the common rail was achieved . The test results show that the real value of the fuel pressure is closer to the ideal value, and the fuel pressure fluctuation is effectively reduced.