Study on dynamic characteristics and control algorithm design for fuel metering valve of high-pressure pump

摘要

High rail pressure and multiple injections are crucial to improve diesel engine performance in terms of fuel efficiency and exhaust emission. As a drawback, rail pressure oscillations and complex pressure-wave propagation phenomena have impact on the control accuracy and response speed. Fuel metering valve, installed on the inlet of high-pressure pump, is the main mechanical actuator to adjust the rail pressure value. In this paper, the co-simulation model was established to investigate the dynamic process which is divided into three phases. The motion dead zones of the valve member and spring preload are the main factors for non-linearity working zone of the fuel metering valve. Therefore, the corresponding segmented control algorithm is designed to adjust the rail pressure based on the fuel flow rate and ideally realize synchronization of the control signals and rail pressure response.