Electrohydraulic Load Sensing System via Compound Control of Flow Feedforward and Pressure Feedback

doi:10.3901/JME.2018.20.262

Abstract

Abstract: To improve the dynamic behaviour and energy efficiency of the existing load sensing technology, an electrohydraulic load sensing (ELS) system is proposed via compound control of flow feedforward and pressure feedback. In this system, the pump displacement is regulated by real-time flow requirement and pressure feedback loop, which is featured by fast response, high stability margin and small pressure margin. The theoretical analysis was carried out to study the response and damping performance in comparison to the existing ELS system via pressure feedback or flow matching, and the corresponding tests on a 2 t hydraulic excavator were also implemented. The results indicate that the proposed system has the advantages of faster response, higher damping performance, and smaller energy consumption through smaller pressure margin. Moreover, dynamic flow matching of the supplement and requirement is fulfilled by pressure feedback, so pressure impacts and energy losses caused by flow excess are avoided in the proposed system.

Key words: electrohydraulic control, flow matching, load sensing, mobile machinery, pressure feedback

CLC Number:

TG156

CHENG Min, YU Jin, DING Ruqi, CAI Leping. Electrohydraulic Load Sensing System via Compound Control of Flow Feedforward and Pressure Feedback[J]. Journal of Mechanical Engineering, 2018, 54(20): 262-270.

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