Co-Simulation Research of the Mechanical-Hydraulic-Control Coupling System of ITER Tractor

The virtual prototyping models of the mechanical, hydraulic and control system of the ITER tractor were built with CATIA, ADAMS and MATLAB/Simulink respectively according to its heavy load and high precision characteristics, and the data transfer between the different models was accomplished by the integration interface between different software. Consequently the virtual experimental platform for the multi-disciplinary co-simulation was established. A co-simulation study of the mechanical-hydraulic-control coupling system of the ITER tractor was carried out. The synchronization servo control of parallel hydraulic cylinders was implemented, and the tracking control of the preconcerted trajectory of the hydraulic cylinders was realized on the established experimental platform. This paper presents the optimization design and technology rebuilding for the complicated coupling system with its theoretic foundation and co-simulation virtual experimental platform.

中国煤炭开采技术及装备50年发展与创新实践--纪念《煤炭科学技术》创刊50周年

回顾《煤炭科学技术》杂志推动和见证中国煤炭开采技术及装备50年发展与创新实践的发展概况,阐述从煤矿机械化到煤矿智能化的创新历程并重点分析采煤机装备技术研发支撑煤炭开发工艺变革,综述煤矿装备智能化迭代发展并提出煤矿装备智能化发展思路。煤炭开采技术历经炮采、普通机械化开采、综合机械化开采、智能化开采4次重大技术变革,实现了煤炭生产力的巨大进步。采煤机装备研发支撑煤炭开发工艺变革,液压支架支护理论、设计方法、支架架型结构和制造技术的创新支撑实现我国液压支架产品由低端到高端的突破;采煤机制造工艺、机型适应性和监控系统等短板技术攻坚取得重大进展,采高0.8~9.0 m全系列采煤机满足我国煤矿高效生产要求,智能化水平不断提升;大运量长运距工作面刮板输送机关键技术不断突破,450 m超长工作面大运量刮板输送机可靠运行,智能变频一体机传动代替传统CST等传动,节能近30%;大运量带式输送机永磁直驱、芳纶带和无基础带式输送机结构等技术创新具有节能、可靠和智能的显著优势;电液控制和无人化智能开采控制技术快速发展,国产化SAC型液压支架电液控制系统、SAM型工作面自动化系统和SAP型智能供液系统广泛应用;“掘锚一体机+锚运破+大跨距转载”掘锚一体机系统、悬臂式掘锚护一体机+临时支护系统和TBM全断面硬岩掘进系统,解决了采掘失衡难题;智能变频节能传动支撑矿山节能,采煤机装备全面国产化创新与智能制造能力快速提升,研发的30多种煤矿机器人在陕煤柠条塔煤矿集群应用,取得良好效果。煤矿智能化技术快速迭代发展,分析了煤矿数据流分类与关联,提出了煤矿智能化总体技术架构与“分级抽取-关联分析-虚实映射”的数据处理基础理论,综述了煤矿智能化系统耦合与迭代开发进展以及煤矿智能化技术标准体系建设进展,提出包括构建以“煤智云”为基础的数据价值生态,推进复杂条件智能开采工艺与装备及煤矿机器人集群研发,建设系统智能与人文智慧融合的煤矿智慧生态的煤矿智能化发展思路,为企业高质量发展指明了技术方向。

A new classification of seepage control mechanisms in geotechnical engineering

Seepage flow through soils,rocks and geotechnical structures has a great influence on their stabilities and performances,and seepage control is a critical technological issue in engineering practices.The physical mechanisms associated with various engineering measures for seepage control are investigated from a new perspective within the framework of continuum mechanics;and an equation-based classification of seepage control mechanisms is proposed according to their roles in the mathematical models for seepage flow,including control mechanisms by coupled processes,initial states,boundary conditions and hydraulic properties.The effects of each mechanism on seepage control are illustrated with examples in hydroelectric engineering and radioactive waste disposal,and hence the reasonability of classification is demonstrated.Advice on performance assessment and optimization design of the seepage control systems in geotechnical engineering is provided,and the suggested procedure would serve as a useful guidance for cost-effective control of seepage flow in various engineering practices.

Characteristics and control mechanisms of coalbed permeability change in various gas production stages

According to dimensionless analysis of the coalbed methane （CBM） production data of Fanzhuang block in southern Qinshui basin, the dimensionless gas production rate is calculated to quantitatively divide the CBM well production process into four stages, i.e., drai- nage stage, unstable gas production stage, stable gas pro- duction stage, and gas production decline stage. By the material balance method, the coal reservoir permeability change in different stages is quantitatively characterized. The characteristics and control mechanisms of change in coalbed permeability （CICP） during different production stages are concluded on five aspects, i.e., permeability trend variation, controlling mechanism, system energy, phase state compositions, and production performance. The study reveals that CICP is characterized by first decline, then recovery, and finally by increase and is controlled directly by effective stress and matrix shrinkage effects. Further, the duration and intensity of the matrix shrinkage effect are inherently controlled by adsorption and desorp- tion features.

Hydraulic fracturing induced casing shear deformation and a prediction model of casing deformation

To study the casing deformation(CD)in shale gas well fracturing caused by natural fracture slip,a fracture face stress model is built based on stress analysis,and a CD prediction model is established based on complex function to analyze factors affecting wellbore shear stress and CD.(1)The fracture and wellbore approach angles have significant impacts on the wellbore shear stress.In Weiyuan shale gas field,Sichuan Basin,under the common wellbore approach angle of nearly 90°,the wellbore is subjected to large shear stress and high risk of CD at the fracture approach angle range of 20° to 55° or its supplementary angle range.(2)When the fracture is partially opened,the wellbore shear stress is positively correlated with the fluid pressure,and negatively correlated with the fracture friction coefficient;when the fracture is fully opened,the wellbore shear stress is positively correlated with the natural fracture area.(3)The lower the elastic modulus and the longer the fracture length,the more serious the CD will be,and the Poisson’s ratio has a weak influence on the CD.The deformation first increases and then decreases with the increase of fracture approach angle,and reaches the maximum when the fracture approach angle is 45°.(4)At a given fracture approach angle,appropriately adjusting the wellbore approach angle can avoid high shear stress acting on wellbore,and reasonable control of the fluid pressure in the fracture can reduce the CD risk.The shear stress acting on casing is usually much greater than the shear strength of casing,so increasing casing strength or cementing quality have limited effect on reducing the risk of CD.Caliper logging data has verified that the CD prediction model is reliable,so the model can be used to establish risk analysis chart and calculate deformation value,to provide a reference for quick CD risk prediction in fracturing design.

On the Construction of Deepening Anti - corruption Mechanism

It needs the foundation of system and the guarantee of organizational system for anti-corruption,but it is more necessary to build and form an effective anti-corruption mechanism,so that the anti-corruption can be really put into practice. Anti-corruption mechanism refers to a organic operation system of the interaction,interconnection and constraint between the constituent elements( parts) and elements of national anti-corruption,and as a system,anti-corruption mechanism should have the characteristics of system aticness,comprehensiveness,transparency,legalization,public participation,scientific dynam ic,and internationalism. The construction of deepening anti-corruption mechanism is the need for reconstructing the ruling legitimacy of the party and the governm ent. Adhering to the principle of treating both root causes and symptoms is necessary in the construction of anti-corruption m echanism,com bating and punishing corruption is an important part of anti-corruption,and the prevention and control of corruption is the basic project of anti-corruption. Therefore,the construction of prevention and control mechanism in the anti-corruption mechanism has a more far-reaching significance.

数字孪生下的液压缸机械运行位置自动控制

液压缸机械系统非线性特征复杂,机械运行行为特征不明确,位置控制结果存在偏差,对此,该文提出数字孪生下的液压缸机械运行位置自动控制方法。连续检测液压缸机械系统运行状态,构建非线性状态方程,对比实际测量数据与输出数据的差异,选取RBF核函数与支持向量机,机械运行位置变化量,描述机械运行行为特征,建立位置控制目标函数,将最高适应度值对应的位置点自动更新为副本位置点,引入猫群算法求解目标函数,对位置控制目标函数的全局最优解展开更新,实现液压缸机械运行位置自动控制。实验结果表明,所提方法应用后,位移检测曲线与实际位移曲线之间的偏差较小,且在恒负载工况下和变负载工况下,位移稳态误差均较小,说明其机械运行位置自动控制结果精度高、控制效率高、控制精度高。

基于模糊神经网络PID的煤矿掘进机俯仰控制研究

目前煤矿掘进机俯仰控制主要采用PID控制方法,在掘进机俯仰控制时变性与液压系统非线性情况下的控制精度不高。掘进机俯仰控制通过控制液压缸行程实现,将传统PID算法与模糊控制、神经网络等相结合,可有效提高液压缸行程控制精度。提出了一种基于模糊神经网络PID的煤矿掘进机俯仰控制方法。通过分析掘进机支撑部运动学关系,得到俯仰角与支撑部液压缸的数学关系;介绍了掘进机俯仰控制液压系统工作原理,建立了液压系统及其传递函数模型;将模糊控制与神经网络相结合,形成模糊神经网络,利用模糊神经网络优化PID控制参数,再结合支撑机构数学模型和液压系统传递函数模型,建立掘进机俯仰角模糊神经网络PID控制模型,实现煤矿掘进机俯仰机构自动精确控制。该方法可使掘进机俯仰机构更加快速、准确到达预设位置,解决掘进机俯仰控制中的时变性与非线性难题。仿真结果表明:模糊神经网络PID控制算法相较于模糊PID和PID控制算法,跟踪误差分别降低了69.34%和74.49%。通过液压缸位移控制模拟煤矿掘进机在突变工况和跟随工况下的俯仰控制,结果表明:模糊神经网络PID控制算法相比模糊PID和PID控制算法,俯仰控制跟踪误差最小,对位置信号的平均响应时间分别缩短了27.22%和50.33%,动态控制性能更好。

基于RSS-ERT的智能决策系统在涡轴涡桨发动机控制系统机械液压产品试验领域的设计与应用

控制系统机械液压产品是涡轴涡桨发动机控制指令的重要执行元件,其生产装配完成后需要使用专用试验设备进行性能调试,调试合格后方可装配发动机。由于控制系统机械液压产品结构复杂,调试过程烦琐,对试验操作人员的技术水平要求较高,须构建一套基于放回取样策略-极端随机树(Return Sampling Strategy-Extreme Random Tree,RSS-ERT)的智能决策系统。通过在调试过程中采集试验数据并根据产品性能反馈调试决策,降低了调试过程对试验操作人员的技术依赖,提高了调试效率。选取某型号燃油调节器进行系统功能验证,结果表明智能决策功能反馈准确,能够满足使用需求。

坚硬顶板切顶卸压技术对巷道围岩变形规律影响

针对特厚煤层坚硬顶板、宽煤柱条件下临空巷道面临的高围岩应力、大变形等问题,以老石旦煤矿16403综放工作面为工程研究背景,从宽煤柱顶板侧向破断结构角度对临空巷道大变形的影响因素进行了理论分析,采用数值模拟方法研究了对16402运输巷实施不同切顶卸压方案时,临近采空区的16403回风巷侧向顶板采动应力传递规律,并在现场施工水力压裂钻孔进行切顶卸压,实现临空巷道围岩变形控制。研究结果表明:“低位坚硬岩层悬臂梁+高位坚硬岩层砌体梁”破断结构是特厚煤层宽煤柱临空巷道大变形的主要原因,可采用切顶卸压技术破坏宽煤柱顶板侧向破断结构来控制临空巷道围岩大变形;切顶角变化可使关键块B长度发生改变,切顶角越大,则关键块B长度越小,临空侧顶板载荷向煤柱传递的程度越弱,临空巷道围岩承受的采动应力越小,切顶角为100°时临空巷道围岩垂直应力与变形量最小;在16402运输巷以切顶角100°施工水力压裂钻孔后,16403回风巷顶底板变形量较未实施切顶卸压的16402回风巷减小86.5%,两帮变形量减小87.1%,临空巷道围岩稳定性得到极大提高。

EBZ-132SH型掘进机的行走机构及其液压系统设计

介绍了EBZ-132SH型掘进机行走机构的组成及工作原理,并对行走机构的5个部分液压系统进行设计和说明,在此基础上提出用电液比例控制阀做先导阀来控制行走马达从而达到对掘进机行走方向的控制。

履带式果园喷药机遥控作业系统设计

为解决传统喷药机依靠人工驾驶,易引起工作人员中毒的问题,针对履带式果园喷药机,设计了一种喷药机遥控作业系统。遥控系统采用ECU作为控制核心,采用飞控系统替代传统的遥控系统进行无线远距离通信,采用液压阀组控制液压油缸来驱动操纵杆动作,从而实现对喷药机的启停、转向和喷药等远距离操纵。在履带式果园喷药机上集成该系统,对系统进行了性能测试,结果表明:系统的有效遥控距离不小于200m,在遥控距离不超过200m的条件下,行走控制响应时间不大于0.6s,遥控距离对系统响应时间几乎没有影响。通过人为切断无线信号的方法,进行了模拟掉线试验,结果表明:喷药机在遥控系统掉线后的停车成功率达到100%。系统具有响应快、通信稳定和安全性高的特点,能够满足果园喷药作业要求。

液压机械控制虚拟仿真实验系统设计与应用

液压机械控制实验系统机理复杂,且传统实验方案不仅成本高,还极易出现因机械故障影响实验进度等问题,因此,液压机械控制实验系统的实际使用效果并不理想。本文提出一种基于虚拟仿真技术的液压机械控制实验系统设计方案,通过合理化的功能设计,实现不同环境要素下的多种工况仿真,不仅能够丰富液压机械控制实验系统功能构成,还可以降低相关实验成本,并显著避免系统故障对实验进度的影响。

液力计算法及DFI-PID下液力缓速器恒力矩制动性能建模与仿真分析

重型车辆在崎岖山路或下长坡行驶时,可以通过控制液力缓速器实现恒力矩制动特性达到稳定行驶的目的。针对液力缓速器能在短时间内产生高制动力现象,提出一套液压控制系统,实现缓速器恒力矩制动性能。这套控制系统通过考虑缓速器充液率、排油阀开度和内腔油压,采用液力计算法解决液力缓速器建模的液力损失问题。并基于整车制动仿真和微分先行增量式PID(DFIPID)控制策略仿真,建立液力缓速器液压控制联合仿真的模型,得到在较高充液率情况下,排油阀开度和内腔油压的变化规律,最终实现恒力矩制动性能的控制。分析结果表明:在制动过程中,在较高充液率的前提下,需要调节排油阀的开度来保证液力缓速器较高强度的恒力矩功能。

液黏调速系统传动机理建模与仿真分析

液黏传动作为一种新型的流体传动技术,其具有结构紧凑、重量轻、效率高、能实现无级调速等优势。然而由于其内部结构复杂、模型的结构和参数受温度影响较大,时变的参数导致模型的参数难于精确获取等因素,因此采用机理对其建模仿真十分困难。针对上述问题,以AMESim软件为平台,基于液黏调速机理建立了包括液压控制模型、轴向动力学模型、旋转动力学模型和负载模型在内的液黏调速系统综合模型,并建立了油膜刚度/阻尼与厚度、润滑油压和转速差的关联模型,进行了不同输入转速下的仿真与试验数据对比,结果表明液黏调速系统一体化多参数模型可以表现出实际工作中大迟滞、非线性的工作特性,在带排状态下输出转速等参数与实际效果接近,准确度达到92.39%,为液黏调速系统的结构优化、性能评估和精准控制提供验证平台。

美卓HP800圆锥破碎机常见故障及处理方法

针对美卓HP800圆锥破碎机常见故障进行了全面、深入的研究,包括机械、液压和电控系统的故障类型,并依据多学科理论如轴承学、流体力学和电子工程,结合实际操作经验,提出了一系列具有针对性和高实用性的解决方案。这些措施有效减少了设备的停机时间,显著提高了整体系统的可靠性和效率,为设备生产的稳定性提供了科学依据,有助于推动相关企业和技术人员在设备管理和维护方面达到更高的工作水平,对矿山设备管理和维护实践具有重要参考价值。

YZB-S型柱塞式液压泵综合试验台的设计与实现

YZB-S型柱塞式液压泵综合试验台是根据用户需求在借鉴国内外新产品、新技术和新工艺的基础上而设计的。设计注重试验项目的工况建立、试验参数采集、处理、标定、校正等内容,并对关键参数进行闭环控制及实时监控。该试验台是机电液一体的自动(一键式操作模式)兼手动试验设备。

基于液压直驱门轴摆动机构多平台仿真的控制特性分析与优化

为提高液压直驱门轴摆动机构的控制特性,减小超调量以及稳态误差等关键指标,基于多软件机液一体化联合仿真方法对系统控制特性进行仿真优化。为了提高仿真模型的精度,使用AMESim、ADAMS以及MATLAB软件建立联合仿真模型;针对摆动机构存在的时变性、死区等问题,采用自适应模糊PID控制算法调整合适的控制参数,对控制系统进行改进。仿真结果表明:相比普通PID控制,调整后的模糊PID控制算法系统超调量减小了75.32%,调节时间缩短了29.56%,稳定误差减小了71.97%。

液驱并联机构多维力加载系统CMAC-模糊PID控制

针对液驱并联机构多维力加载系统非线性、时变和强耦合的系统特性,提出一种改进PID控制策略以提高系统输出精度。通过构建多维力加载系统动力学模型与液压动力元件模型,分析研究耦合力产生机理。将多维力加载时受系统自身结构影响的各通道间耦合力与系统参数摄动等非线性因素视为干扰,采用模糊控制对PID参数进行实时调整,抑制系统非线性干扰以提高跟踪精度;考虑到传统经验法或专家知识库的模糊推理对PID控制参数调整不够精细,提出一种模糊PID与小脑模型神经网络(cerebellar model articulation controller,CMAC)并行的控制策略,利用其自适应能力与快速学习非线性函数能力对模糊PID控制过程进行学习和插补。研究结果表明:与PID控制器相比,CMAC-模糊PID控制器能够有效地解决液驱并联机构多维力加载系统复杂的跟踪问题。

液压机械式压差伺服系统的差分进化H_(∞)优化设计方法

针对液压机械式压差伺服系统正向设计的难点,提出压差伺服系统的差分进化H∞优化设计方法。通过建立状态空间模型,并设计差分进化H_∞频域优化指标,提出一种压差伺服系统的动态设计方法;在此基础上,完成了压差伺服系统镇定、伺服控制规律的优化设计,并进行系统级仿真。仿真结果表明,压差伺服系统稳态特性满足0.92±0.01 MPa,静态误差小于1%,动态调节时间小于0.01 s,超调量小于10%,相角裕度大于70°,20 Hz正弦波动输入信号的干扰下具有鲁棒抗干扰性能。