Journal of Zhejiang University-SCIENCE A

, Volume 18, Issue 6, pp 430–442 | Cite as

Valve-based compensation for controllability improvement of the energy-saving electrohydraulic flow matching system

Article
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Abstract

The energy-saving electrohydraulic flow matching (EFM) system opens up an opportunity to minimize valve losses by fully opening the control valves, but the controllability is lost under overrunning load conditions. To address this issue, this paper proposes a valve-based compensator to improve the controllability of the energy-saving EFM system. The valve-based compensator consists of a static compensator and a differential dynamic compensator based on load conditions. The energy efficiency, the stability performance, and the damping characteristic are analyzed under different control parameters. A parameter selection method is used to improve the efficiency, ensure the stability performance, and obtain good dynamic behavior. A test rig with a 2-t hydraulic excavator is built, and experimental tests are carried out to validate the proposed valve-based compensator. The experimental results indicate that the controllability of the EFM system is improved, and the characteristic of high energy efficiency is obtained by the proposed compensator.

Key words

Compensation control Energy efficient Flow matching Mobile machinery 

基于阀补偿的电液流量匹配节能系统的动态性能改进

摘要

目 的

电液流量匹配系统通过前馈指令信号来调节泵排量,故可采用增大阀口开度的方法来降低能量损失,但是该方法降低了超越负载工况下的操控性能。为改进该工况下的系统动态性能,本文旨在研究电液流量匹配系统泵阀控制方法,在提高系统效率的前提下,提高系统动态性能。

创新点

提出了基于比例阀补偿的动态性能改进方法,研制了考虑动静态性能补偿的比例阀控制器,提高了系统速度控制性能。

方法

1. 建立电液流量匹配节能系统数学模型,分析在超越或阻抗工况下的系统速度控制需求;2. 提出基于比例阀开口补偿的控制方法(图2)以提高系统动态性能;3. 相对于传统阀口控制方法,分析提出的方法在不同负载工况下的节能特性;4. 通过频域分析法研究系统稳定性,并提出保证系统稳定和动态性能的参数选取准则。

结论

1. 相比传统阀口控制方法,提出的基于比例阀补偿的控制方法能够提高3.2%~6.8%的系统效率;2. 相对于阀口全开控制方法,所提方法的优势在于能保证系统在不同工况下的动态控制性能,尤其能保证在超越负载工况下的系统可控性;3. 所提方法不仅提高了设备的效率,也保证了系统的操控性能。

关键词

补偿控制 节能 流量匹配 移动机械 

CLC number

TH137.1 

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Copyright information

© Zhejiang University and Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Min Cheng
    • 1
    • 2
  • Bing Xu
    • 2
  • Jun-hui Zhang
    • 2
  • Ru-qi Ding
    • 2
    • 3
  1. 1.State Key Laboratory of Mechanical Transmissions, School of Mechanical EngineeringChongqing UniversityChongqingChina
  2. 2.State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhouChina
  3. 3.School of Mechatronic EngineeringEast China Jiaotong UniversityNanchangChina

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