Abstract
With the rapid development of the global economy, more and more attention has been paid to the energy conservation of construction machinery. The hydraulic system is the key component of construction machinery, and improving its energy utilization rate has become an important means to achieve energy conservation. In conventional valve-controlled or pump-controlled hydraulic systems of construction machinery, controllability and energy-saving performance typically cannot be considered at the same time. The pump-valve coordinated system combines the energy-saving characteristics of the pump-controlled system and the high-precision and high-frequency response of the valve-controlled system, which has the potential to become a primary research direction of electro-hydraulic systems. This review summarizes the recent research progress in energy-saving technologies based on pump-valve coordinated systems. Particularly, we discuss the structures of hydraulic systems in different categories of construction machinery, various control methods of the electro-hydraulic system, novel hydraulic hybrid energy regeneration systems, and key components. In addition, future directions and challenges of the pump-valve coordinated systems are described, such as independent metering system (IMS), common pressure rail (CPR), and hybrid power source (HPS).
概要
随着全球经济的飞速发展和工程机械全球保有量 的持续上升,工程机械的节能问题变得越来越突 出。液压系统是工程机械的关键子系统,因此提 高其能源利用率是当前实现工程机械节能的重 要手段之一。而在传统的阀控或泵控液压系统 中,由于受阀件和液压泵的固有特性制约,系统 可控性和节能性通常无法得到兼顾。泵阀协控系 统将泵控系统的节能特性与阀控系统的高精度 和高频率响应相结合,使其成为当前电液系统的 一个研究热点。本文总结了泵阀协控电液系统节 能技术的最新研究进展,并重点分析了不同类型 工程机械的液压系统结构、电动液压系统的控制 方法、新型液压混合能量再生系统以及关键部 件。同时,从负载口独立控制技术、共压导轨技 术(CPR)和混合动力源系统三个方面探讨了泵 阀协控系统的未来发展方向和面临的挑战。
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Zhe-ming TONG and Shuang-shuang WU designed the research and wrote the first draft of the manuscript. Shui-guang TONG and Yu-wei ZHONG conducted the literature review. Yu-qing YUE and Yuan-song LI processed the data. Shui-guang TONG and Zheng-yu XU revised the final version and provided the funding support.
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Zhe-ming TONG, Shuang-shuang WU, Shui-guang TONG, Yu-qing YUE, Yuan-song LI, Zheng-yu XU, and Yu-wei ZHONG declare that they have no conflict of interest.
Project supported by the Zhejiang Provincial Natural Science Foundation of China (No. LR19E050002), the National Key R&D Program of China (No. 2019YFB2004604), the National Natural Science Foundation of China (Nos. 51821093 and 51708493), the Key R&D Program of Zhejiang Province (Nos. 2018C01020 and 2018C01060), and the Youth Funds of the State Key Laboratory of Fluid Power and Mechatronic Systems (No. SKLoFP_QN_1804), China
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Tong, Zm., Wu, Ss., Tong, Sg. et al. Energy-saving technologies for construction machinery: a review of electro-hydraulic pump-valve coordinated system. J. Zhejiang Univ. Sci. A 21, 331–349 (2020). https://doi.org/10.1631/jzus.A2000094
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DOI: https://doi.org/10.1631/jzus.A2000094