共查询到16条相似文献,搜索用时 125 毫秒
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对盾构推进系统的液压缸采用分区控制,以达到降低系统复杂程度、保证控制精度的目的。用液压仿真软件AMESim对推进液压系统进行仿真模拟分析,采用开环与闭环两种方式。仿真结果表明,压力流量闭环控制较开环控制可以有效减少压力和流量的波动,实时控制推进压力和推进速度,控制效果较好。 相似文献
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《机械工程与自动化》2017,(5)
盾构机用于市政修建时,其设计轴线与施工隧道的偏差是衡量施工质量的重要指标,故液压缸的精确控制十分重要。首先分析德国海瑞克R438盾构机推进系统控制原理,其次利用AMESim搭建压力和流量开、闭环仿真模型。由仿真结果可知:开环控制下,压力(流量)改变时,流量(压力)随着会发生大的波动;闭环控制下,压力和流量之间的相互影响作用被大大削弱。因此,得出压力流量双闭环控制可以更好地满足推进系统的控制要求。 相似文献
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盾构机作为城市隧道建设的主要工程设备,已在我国得到了广泛的使用.在德国海瑞克盾构机的基础上进行国产化设计的盾构机为对象,论述其液压推进系统的组成及其工作原理,通过AMESIM软件建立推进系统模型,对其进行仿真分析.通过仿真发现,压力流量复合控制方式可以减小压力和流量的波动,提高推进系统的性能,更好地实现对盾构机的精密控制. 相似文献
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盾构推进系实现了盾构机的前进及转弯功能。针对盾构推进系统的结构特点,对系统中的各元器件进行原理结构分析并建立数学模型。基于Modelica语言在多领域仿真平台MWorks中建立推进系统动态特性分析的通用模型组件库,对推进系统的仿真模型进行动态特性分析。分析结果表明,换向过程中系统压力出现突变,系统震荡加剧,不利于系统的稳定;而系统中流量的波动变化较小,对系统稳定性影响较弱;减小压力波动对实现系统稳定意义重大。该模型符合盾构机在实际工况下推进系统的工作特性,在模型中能获得时域范围内系统的压力和流量脉动情况。 相似文献
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In this study, a throttling venturi valve with adjustable area was designed to control the thrust of a monopropellant thruster using hydrogen peroxide. The flow rate control characteristics of the throttling venturi valve were investigated based on the pintle stroke and upstream pressure of the venturi. Three kinds of experiments were conducted: pressure and flow rate measurement according to pintle stroke and venturi upstream pressure, determination of critical pressure ratios under various conditions, flow rate control performance through open-loop control and feedback control of an actuator. The pressures were measured at the upstream, throat, and downstream of the venturi. It was observed that the flow rate changed in proportion to the stroke and upstream pressure. Below a stroke of 10 mm, the critical pressure ratio gradually decreased as the stroke and upstream decreased. However, above a stroke of 10 mm, the critical pressure ratio converged to a value between 0.7 and 0.8 regardless of the upstream pressure. The results of automatic flow rate control tests using open-loop control and feedback control showed that the measured flow rate satisfactorily followed the target flow rate profile. 相似文献
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Hydraulic thrust system is an important system in a shield tunneling machine. Pressure regulation of thrust cylinders is the most important function for thrust system during tunnel excavation. In this paper, a hydraulic thrust system is explained, and a corresponding simulation model is carried out in order to study the system characteristics. Pressure regulation of a certain group’s cylinders has little influence on regulation of the other groups’ cylinders. The influence will not affect the process much during tunnel excavation. Pump displacement may have a greater effect on pressure regulation and oil supply flow rate should be adaptive to the system’s demand. A exacting situation is simulated to explain how pressure regulation works during tunnel excavation. 相似文献
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为了评估银盘水电站推力轴承支撑性能对机组运行的稳定性以及验证镜板泵外循环技术在设计工况下的冷却效果,通过对不同结构特点推力轴承支撑性能进行分析,阐述了银盘水电站推力轴承弹性油箱支撑结构在轴流转桨式水轮发电机组中自动调整各轴瓦受力平衡的优点;同时,利用流体力学计算公式,对银盘水电站镜板泵外循环系统工作压头和流量进行了计算分析,结合现场机组运行工况进行了试验验证。研究结果表明:采用弹性油箱支撑结构的推力轴承,能使推力轴承轴瓦间受力不均匀的问题得到根本改善,大大提高了机组运行的稳定性;通过计算分析,结合机组运行监测数据,得出了银盘水电站镜板泵实际压头系数和流量系数,证明镜板泵外循环系统能够在设计工况点附近工作,从检测数据来看系统冷却效果较好。 相似文献