中文摘要：

在液压传动系统中，由于控制阀突然关闭或负载运动突然换向，会产生液压冲击现象。液压冲击严重影响系统的平稳运行，降低元器件的使用寿命，甚至使执行器产生误动作，造成安全事故。如炼钢高炉扒渣机大臂液压控制回路就存在这种问题，由于负载惯性大，换向频繁，液压冲击现象严重，造成扒渣机大臂驱动马达寿命短，频繁更换，影响了生产效率。为改善这种现象，对大惯性负载液压系统中的液压冲击现象进行研究和分析，提出一种主动缓解液压冲击的方法，利用换向控制信号主动预测冲击峰值压力的出现时间，并据此调整用于缓冲的可变阻尼，达到缓解液压冲击的目的。理论上阐述该方法的原理，利用数字仿真和现场测试进行验证。结果表明，该方法具有速度快、能耗低的优点，在满足系统响应特性的前提下，可有效降低系统的液压冲击。

英文摘要：

Hydraulic impact often occurs when the control valve shuts down or the load movement reverses suddenly in hydraulic transmission system. Hydraulic impact influences smoothness and stable running of hydraulic system, reduces the service life of hydraulic elements, and even makes the actuator have false action which leads to the accidents that can be illustrated by the hydraulic control circuit of the slipping ann of cinder scraper of steeling-making furnace. The high load inertia and frequent alternating direction lead to the serious hydraulic impact which shorten the age limit of the hydraulic motor driving the cinder scraper＇s slipping arm and make the hydraulic motor changed frequently, thus to affect the production efficiency. In order to improve this phenomenon, the hydraulic impact in large inertia load＇s hydraulic system is analyzed, and a method is proposed to alleviate the hydraulic impact. This method is to pre-calculate the time when the peak pressure arrives by controlling signals, and adjust the variable damping used in buffing the impact so as to reduce the hydraulic impact. The principle of this approach is explained in theory which is verified by digital simulation and field test. The result of simulation and field test testifies the method bears the advantages of being quick dynamic and having low energy consumption, which can reduce the hydraulic impact effectively in the premise of satisfying the characteristic of system response.