Research on the performance of hydraulic excavator boom based pressure and flow accordance control with independent metering circuit

Applying the independent metering circuit on the excavator is an effective way to reduce energy consumption and improve the performance of the actuators, e.g. the boom in the negative load circuit. This paper aims to improve the energy efficiency and the stationarity of the boom system based on the independent metering circuit using the strategy of flow and pressure accordance, pump and valve coordinate in dynamic and static. After studying the mechanic structure of the boom, principles of the system and elements characteristics, the four control strategies are designed to settle the problems in the traditional throttling system using mechanically connected orifices valves such as the load-sensing system and new coordinate challenges brought with the multivariable. Finally, experiments based on load sensing and independent metering circuit are implemented on a physical prototype. The experimental results show that the energy consumption of the boom system falls by 15% compared to the load-sensing system; the pressure pulsations of the pump when the boom starts to move reduce from 6.9 MPa to 1.7 MPa. Therefore, the independent metering circuit and the control strategy are good configuration for the boom actuator.