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滑阀副径向卡紧力分布模型与参数灵敏度分析

航空动力学报 2024年第1期39卷 177-186页

作者：陈志闯葛声宏张卓磊朱玉川南京航空航天大学直升机传动技术重点实验室南京210016 南京机电液压工程研究中心航空机电系统综合航空科技重点实验室南京210061 中航工业南京伺服控制系统有限公司南京210032

为寻求提高批量电液伺服阀分辨率一致性的制造工艺方法,针对滑阀副径向尺寸公差范围内参数摄动作用下卡紧力大小的不确定性,建立了径向卡紧力数学模型,获得了径向尺寸参数摄动下的滑阀副径向卡紧力分布特性。建立了工艺参数与径向卡紧... 详细信息

为寻求提高批量电液伺服阀分辨率一致性的制造工艺方法,针对滑阀副径向尺寸公差范围内参数摄动作用下卡紧力大小的不确定性,建立了径向卡紧力数学模型,获得了径向尺寸参数摄动下的滑阀副径向卡紧力分布特性。建立了工艺参数与径向卡紧力分布特征参数之间映射关系的响应面代理模型,并据此开展了滑阀副径向卡紧力分布特征参数对工艺参数的全局灵敏度分析。结果表明:径向卡紧力服从Weibull分布,改变阀芯圆柱度相比改变径向间隙对滑阀副径向卡紧力影响较小。相比减小径向间隙变动范围,降低径向间隙下限值对提高径向卡紧力一致性更加有效。而相比降低径向间隙下限值,减小径向间隙变动范围对从整体上减小径向卡紧力更为显著。

关键词：滑阀副径向卡紧力分布模型工艺参数灵敏度分析

Development of a novel two-stage proportional valve with a pilot digital flow distribution

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Frontiers of Mechanical Engineering 2021年第2期16卷 420-434页

作者： Qiang GAO yuchuan zhu Changwen WU Yulei JIANG National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Pilot two-stage proportional valves are widely used in high-power hydraulic systems. For the purpose of improving the dynamic performance, reliability, and digitization of the traditional proportional valve, a novel two-stage proportional valve with a pilot digital flow distribution is proposed from the viewpoint of the dual nozzle-flapper valve’s working principle. In particular, the dual nozzle-flapper is decoupled by two high-speed on/off valves (HSVs). First, the working principle and mathematical model of the proposed valve are determined. Then, the influences of the control parameters (duty cycle and switching frequency) and structural parameters (fixed orifice’s diameter and main valve’s spring) on the main valve’s motion are analyzed on the basis of theory, simulation, and experiment. In addition, in optimizing the value of the fixed orifice’s diameter, a new design criterion that considers the maximum pressure sensitivity, flow controllability, and flow linearization is proposed to improve the balance between the effective displacement and the displacement fluctuation of the main valve. The new scheme is verified by simulations and experiments. Experimental results of the closed-loop displacement tracking have demonstrated that the delay time of the main valve is always within 3.5 ms under different working conditions, and the tracking error can be significantly reduced using the higher switching frequency. The amplitude–frequency experiments indicate that a −3 dB-frequency of the proposed valve can reach 9.5 Hz in the case of ±50% full scale and 15 Hz in the case of 0%–50% full scale. The values can be further improved by increasing the flow rate of the pilot HSV.

关键词： two-stage proportional valve digital flow distribution high-speed on off valve position tracking characteristic dynamic performance

Refined modeling and experimental verification of a torque motor for an electro-hydraulic servo valve

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Chinese Journal of Aeronautics 2023年第6期36卷 302-317页

作者： Zhichuang CHEN Shenghong GE Yulei JIANG Wenhao CHENG yuchuan zhu National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing Engineering Institute of Aircraft SystemsNanjing 210061China AVIC Nanjing Servo Control System Co. LtdNanjing 210032China

The Permanent Magnet Torque Motor(PMTM)is the key electro-mechanical conversion device in an Electro-Hydraulic Servo Valve(EHSV).In this work,a refined model of a PMTM is developed,considering the non-working air-gaps between the upper or lower yoke and the armature,the fringing effect at the limiting holes,and the nonlinear permeability of soft magnetic *** on the refined model,the influences of various factors on the calculation accuracy of the magnetic flux at the pole surfaces of the armature and the output torque are *** verifying the validity of the refined model,a Finite Element Analysis(FEA)of the PMTM is conducted,and a test platform is *** with existing models,the refined model can better reveal the intrinsic mechanism of the PMTM,and its calculations are more consistent with the FEA *** experimental results of the armature deflection displacement show that the refined model can accurately describe the output characteristics of the PMTM.

关键词： Calculation accuracy Electro-hydraulic servo valve Experimental verification Finite element analysis Refined model Torque motor

多喷嘴挡板单级电液伺服阀数学模型及特性分析

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液压与气动 2024年第7期48卷 162-170页

作者：王彦文葛声宏陈志闯吴河灯杨瀚浩朱玉川南京航空航天大学机电学院江苏南京210016 中航工业南京伺服控制系统有限公司江苏南京210032

多喷嘴挡板单级电液伺服阀是飞机辅助动力装置的重要部件之一,起到精确控制燃油流量的作用。针对其力矩马达初始气隙非对称、单侧四喷嘴等独特的结构形式,分析了工作机理,建立了整阀的数学模型,并通过MATLAB/Simulink对数学模型进行了... 详细信息

多喷嘴挡板单级电液伺服阀是飞机辅助动力装置的重要部件之一,起到精确控制燃油流量的作用。针对其力矩马达初始气隙非对称、单侧四喷嘴等独特的结构形式,分析了工作机理,建立了整阀的数学模型,并通过MATLAB/Simulink对数学模型进行了仿真研究,得到了各组件以及整阀的输出特性。其中,力矩马达气隙初始值非对称产生的电磁力矩可以平衡一部分喷嘴液压力产生的力矩,考虑喷嘴腔的压力损失与不考虑时二者误差最大为11.4%。同时开展了多喷嘴阀实验研究,对比数学模型与实验得到的整阀流量特性曲线,二者基本一致,验证了所建立的数学模型的准确性,为多喷嘴挡板电液伺服阀特性分析奠定了基础。

关键词：单级伺服阀多喷嘴数学模型流量特性

基于均匀切换的并联数字阀控系统位置控制策略

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中国机械工程 2020年第12期31卷 1461-1468,1480页

作者：高强朱玉川南京航空航天大学机电学院南京210016

针对并联数字阀控系统在脉数调制(PNM)控制下易出现低速定位精度低的问题,提出一种复合控制策略,即低速工况采用差动脉宽调制(PWM)控制策略,其余工况采用基于模型的PNM控制策略。各开关阀切换次数的差异程度在PNM控制下较大,且差异程度... 详细信息

针对并联数字阀控系统在脉数调制(PNM)控制下易出现低速定位精度低的问题,提出一种复合控制策略,即低速工况采用差动脉宽调制(PWM)控制策略,其余工况采用基于模型的PNM控制策略。各开关阀切换次数的差异程度在PNM控制下较大,且差异程度被差动PWM控制进一步放大,因此,为减小各开关阀切换次数的差异程度,基于循环滑动方法分别对PNM和PWM信号进行切换优化。实验结果表明,液压缸的平均定位误差从0.528 mm减小至0.032 mm,最小定位误差从0.221 mm减小至0.003 mm,开关阀切换次数的分布均匀性得到了显著提高。

关键词：数字阀控系统位置控制脉数调制差动脉宽调制均匀切换

射流伺服阀用放大型超磁致伸缩执行器建模及分析

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航空学报 2014年第11期35卷 3156-3165页

作者：朱玉川李跃松南京航空航天大学机电学院江苏南京210016

为提高射流伺服阀的动态性能,设计了采用桥式微位移放大机构的射流伺服阀用放大型超磁致伸缩执行器(AGMA)。建立了计输入位移损失的放大机构模型以及非线性位移输出理论模型,并采用有限元法对所建放大机构模型进行了对比验证,结果表明:... 详细信息

为提高射流伺服阀的动态性能,设计了采用桥式微位移放大机构的射流伺服阀用放大型超磁致伸缩执行器(AGMA)。建立了计输入位移损失的放大机构模型以及非线性位移输出理论模型,并采用有限元法对所建放大机构模型进行了对比验证,结果表明:放大机构的输入刚度模型最大误差40Hz,谐振频率约为30Hz。

关键词：超磁致伸缩执行器射流伺服阀动态模型微位移放大刚度有限元法

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电反馈式超磁致伸缩伺服阀的理论研究

机械科学与技术 2009年第2期28卷 254-257,261页

作者：朱玉川南京航空航天大学江苏省精密与微细制造技术重点实验室南京210016

设计了一种新型超磁致伸缩执行器驱动的喷嘴挡板伺服阀,基于超磁致伸缩材料磁机耦合理论建立了该伺服阀的数学模型,推导了其简化传递函数、稳定性判断准则及稳定裕量计算公式。最后对超磁致伸缩伺服阀的静动态特性进行了理论研究、仿真... 详细信息

设计了一种新型超磁致伸缩执行器驱动的喷嘴挡板伺服阀,基于超磁致伸缩材料磁机耦合理论建立了该伺服阀的数学模型,推导了其简化传递函数、稳定性判断准则及稳定裕量计算公式。最后对超磁致伸缩伺服阀的静动态特性进行了理论研究、仿真实验并与传统喷嘴挡板伺服阀进行了比较,证明了该新型伺服阀具有高频响、高精度、稳定裕度大、静态特性和线性度好等显著优点,并得出了提高超磁致伸缩伺服阀性能的具体途径和方法。

关键词：超磁致伸缩执行器伺服阀频宽稳定性

Development of community health service-oriented computer-assisted information system for diagnosis and treatment of respiratory diseases

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Family Medicine and Community Health 2013年第4期1卷 1-9页

作者： Yuefang Wu Xin Yao Peili Sun Yong Hu yuchuan zhu Yin Hu Department of Respiratory Medicine the First Affiliated Hospital with Nanjing Medical UniversityNanjingJiangsu Province210029China Nanjing University of Science and Technology Hospital NanjingJiangsu Province210094China Jiangsu Shengze Hospital SuzhouJiangsu Province215228China

Objective:Community health services are an emerging *** have found in practice that diagnosis and treatment of respiratory diseases in the community are *** respiratory department’s daily work involves a number of outpatient registration items and a vast *** routine manual operation is inefficient and it is not convenient to make effective statistical analysis of the outpatient data to identify the risk factors closely related to ***,it is imperative to process the outpatient information of patients with respiratory diseases effectively and efficiently in a unified manner by means of computer ***:The design and realization of the Community Health Service-oriented computerassisted Information System for Diagnosis and Treatment of Respiratory Diseases(CHS-DTRD)was completed as part of the community intervention study on bronchial asthma that was carried out jointly by the Nanjing First Hospital Affiliated to Nanjing Medical University and the Hospital of Nanjing University of Science&Technology,and based on 2 years of experience and the needs of an overall ***:The computer-assisted information system for diagnosis and treatment was developed using Java Server Page(JSP)technology and introducing the advanced Asynchronous JavaScript XML(AJAX)technique and MS-SQL Server was used in the background ***-DTRD was composed of eight functional modules(outpatient data maintenance,outpatient appointment,intelligent analysis for disease risk factors,query and statistics,data dictionary maintenance,database manipulation,access control,and system configuration).CHS-DTRD featured a friendly interface,convenient operation,and stability and ***:Community health-oriented diagnosis and treatment of respiratory diseases is simple,programmable,and intuitive,thus the workload of physicians is significantly reduced and the work efficiency is *** system facilitates an intelligent analysis

关键词： Community health service Respiratory diseases Computer-assisted diagnosis and treatment,Intelligent analysis Browser/server

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智能材料驱动的高速开关阀

压电与声光 2019年第4期41卷 575-581页

作者：罗樟朱玉川南京航空航天大学机电学院

高速开关阀作为未来液压控制阀发展的一个方向和研究热点,越来越受到研究者的重视。该文介绍了国内、外智能材料驱动的高速开关阀的研究现状,包括智能材料电-机转换器的类型及其微位移放大装置,以及磁致伸缩、压电叠堆、形状记忆合金与... 详细信息

高速开关阀作为未来液压控制阀发展的一个方向和研究热点,越来越受到研究者的重视。该文介绍了国内、外智能材料驱动的高速开关阀的研究现状,包括智能材料电-机转换器的类型及其微位移放大装置,以及磁致伸缩、压电叠堆、形状记忆合金与磁流体等智能材料驱动的高速开关阀,分析了各类智能材料驱动的高速开关阀的优缺点,得到了各类智能材料在高速开关阀上的应用特性。

关键词：智能材料电-机转换器高速开关阀微位移放大装置脉宽调制