Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

<正>The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining production.Projects undertaken and participated by the copper electrolysis anode preparation equipment,lead residual anode washing pro-     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

<正>The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining production.Projects undertaken and participated by the copper electrolysis anode preparation equipment,lead residual anode washing production     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996. The researches of institute concentrate on electro-hydraulic(pneumatic) servo/proportional control and hydromechatronics. The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining production.     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

<正>The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

<正>The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-     

Development of pressure control system in counter gravity casting for large thin-walled A357 aluminum alloy components

Counter gravity casting equipments（CGCE） were widely used to produce large thin-walled A357 aluminum alloy components. To improve the pressure control precision of CGCE to get high quality castings, a pressure control system based on fuzzy-PID hybrid control technology and the digital assembled valve was developed. The actual pressure tracking experiment results show that the special system by applying PID controller and fuzzy controller to varied phases, is not only able to inherit the small error and good static stability of classical PID control, but also has fuzzy control＇s advantage of fully adapting itself to the object. The pressure control error is less than 0.3 kPa. By using this pressure control system, large complex thin-walled A357 aluminum alloy castings with high quality was successfully produced.     

Study of modeling and simulation of full digital controlled PMIG／MAG welding system based on Matlab／Simulink

This paper presents an integrated simulation model for full digital controlled PMIG/MAG welding system with Matlab/Simulink, and it consists of power inverter, digital control system and dynamic arc-load model. An integrated simulation study was done for fuU digital PMIG/MAG welding, and a method of connecting dynamic arc-load model to the system with controlled current source was presented, in addition, the simulation results were utilized to study the issues of digital control PMIG/MAG welding in this paper. The experimental results validated the developed simulation model, and this simulation study can be applied in implementation of the full digital PMIG/MAG welding and analysis of system dynamic process.     

Gating system optimization of low pressure casting A356 aluminum alloy intake manifold based on numerical simulation

To eliminate the shrinkage porosity in low pressure casting of an A356 aluminum alloy intake manifold casting, numerical simulation on filling and solidification processes of the casting was carried out using the ProCAST software. The gating system of the casting is optimized according to the simulation results. Results show that when the gating system consists of only one sprue, the filling of the molten metal is not stable; and the casting does not follow the sequence solidification, and many shrinkage porosities are observed through the casting. After the gating system is improved by adding one runner and two in-gates, the filling time is prolonged from 4.0 s to 4.5 s, the filling of molten metal becomes stable, but this casting does not follow the sequence solidification either. Some shrinkage porosity is also observed in the hot spots of the casting. When the gating system was further improved by adding risers and chill to the hot spots of the casting, the shrinkage porosity defects were eliminated completely. Finally, by using the optimized gating system the A356 aluminum alloy intake manifold casting with integrated shape and smooth surface as well as dense microstructure was successfully produced.     

基于自抗扰控制的直驱电液伺服系统仿真研究

针对直驱式电液伺服系统中存在的非线性特性和外部扰动导致系统流量供给不平衡问题,基于自抗扰控制理论,提出一种基于三阶线性自抗扰控制的液压缸位置控制方法,实现直驱式电液伺服系统电机转速与液压缸位置的闭环控制。同时针对传统系统建模不精确导致控制效果差的问题,在理论分析的基础上,结合电液伺服系统的性能和实际工况,基于AMESim建立直驱式伺服液压系统仿真模型。通过建立AMESim和Simulink的联合仿真模型,验证控制器的有效性。结果表明：该控制策略可以有效消除由于流量供给不平衡导致的液压缸在换向运动时出现位移波动,液压缸位移的平均绝对百分比误差为4.4%,较好地实现位置跟踪。在外负载扰动的情况下,系统具有较强的抗干扰能力,从而保证系统的稳定性。     

轨道车辆转向架综合参数检测台电液伺服系统动态仿真

针对轨道车辆转向架综合参数检测台定位精度高、响应速度快和实时跟踪的性能要求,建立具有弹性负载的电液伺服系统数学模型。对具有弹性负载的电液伺服系统数学模型中存在的非线性因数进行归一化处理,使其既能体现该电液伺服系统的特性,又方便数学建模。在此电液伺服系统中,以阀控缸对称式液压系统为研究对象,对其进行精确定位和实时跟踪控制。利用Simulink对模型进行动态仿真,结果表明:所建立的数学模型能够高精度地实现电液伺服的控制,满足轨道车辆综合参数检测台实时控制的要求。并详细讨论了影响电液伺服系统动态特性的主要因素。     

电液压力伺服阀简介

电液伺服阀按功能可分为流量伺服阀和压力伺服阀,压力伺服阀常用于施力系统,流量伺服阀可用于施力系统或者位置系统。在大刚度负载系统中,常用的流量伺服阀不能满足系统使用要求,一般需要压力电液伺服阀。介绍单级压力伺服阀、两级半开环压力伺服阀、两级闭环压力伺服阀和直接驱动压力伺服阀等,阐述各类型压力伺服阀的特点和优缺点。     

两种变转速电机驱动恒压泵动态及能效特性研究

为了提高电液动力源响应速度、降低能耗,设计变转速驱动恒压泵组成新型的电液动力源。针对不同工况分别采用变频器驱动三相交流电机和伺服电机两种方式驱动恒压泵,通过对构建的电液动力源原理、动态响应理论分析及试验验证,表明变频器驱动交流电机动态响应差,伺服电机驱动动态响应时间不超过0.1 s。进一步对两种变转速驱动进行能耗分析,试验结果表明两种电液动力源能效随着负载压力和转速的升高而增大,当负载压力达到20 MPa、转速提升到1 500 r/min,变频异步电机驱动的液压系统能效为0.74,伺服电机驱动的液压系统能效为0.8。     

径向锻造油压机电液伺服控制系统建模与仿真

分析了径向锻造油压机主缸运动电液伺服控制原理;在建立电液伺服系统各元件、子系统数学模型的基础上,借助AMESim软件搭建了电液伺服系统的仿真模型;研究了反馈方式、回程压力、建压时间和加载频次对主缸运动精确性和快速性的影响。研究结果表明:与主缸位置反馈相比,伺服缸位置反馈时系统运行更加平稳;为保证系统的响应速度和主缸对伺服缸的跟随性,合理的回程压力为3~12 MPa;为保证系统的快速性、精确性及系统的经济性,尽量减少建压时间;主缸供液高压油液体积50000 mL时,伺服缸时间滞后0. 03 s,主缸对伺服缸跟随滞后0. 01 s;系统流量确定时,锻造频次增加使得锻造行程减小,控制精度降低,系统响应滞后。     

直驱式电液伺服系统及其在注塑机上的应用

建立了直驱式电液伺服系统的数学模型，进行了仿真分析和试验研究。结果表明，在频响不高的场合直驱式电液伺服装置完全可替代传统的电液伺服装置。     

一种节能非线性电液伺服系统双层模糊控制方法研究

为了降低电液伺服阀控制系统能量损失,设计了双层模糊控制器,并对电液伺服系统能量进行仿真验证。分析了电液伺服阀模型简图,建立了电液伺服阀动力学模型,推导出比例溢流阀的开启压力与泵压的关系方程式。设计变论域双层模糊控制方法,分别对电液伺服系统负载反馈和输出误差反馈进行在线调节,通过MATLAB软件对控制系统节能效果进行仿真验证,并且与传统PID控制方法进行对比和分析。结果表明:采用传统PID控制方法的电液伺服系统输出误差较大、能量损失较多;采用双层模糊控制方法的电液伺服系统输出误差较小、能量损失较少。采用双层模糊控制方法,能够提高非线性电液伺服系统输出精度,从而有效减小了控制系统的能量损失。     

外骨骼关节驱动神经网络滑模力控制研究

针对外骨骼机器人液压关节驱动系统具有非线性、不确定参数等特性,导致模型建立困难以及负重时具有不确定冲击扰动的问题,基于电液伺服系统特性,建立以弹性负载为外负载的数学模型。为减小负重时冲击扰动项对力控制的影响,引入径向基（RBF）神经网络对干扰项进行补偿,设计一种基于RBF神经网络的滑模力控制策略。通过系统特性进一步验证模型可行性,并进行仿真试验对比。结果表明：与PID控制相比,所设计的控制策略响应时间更短,跟踪误差缩小70.5%;变负载工况下,所设计的控制策略具有更好的跟随能力、更强的鲁棒性能,可以满足外骨骼机器人关节驱动的力控制要求。平台试验进一步验证了仿真结果的有效性与正确性。     

高升率液压脉冲系统机制分析与设计

为模拟航空作动器高压力、高升率工作环境进行脉冲试验,设计了T形波脉冲系统,系统采用压力传感器和电液伺服阀构成闭环控制,通过控制经伺服比例阀流入非对称增压缸低压腔的流量建压。在建立蓄能器、电液伺服阀及增压缸-被试工装件的压力-流量数学模型的基础上,基于AMESim搭建仿真模型,对比分析不同工装件容积、脉冲升率对系统动态性能的影响。仿真结果表明,系统主要由蓄能器提供瞬时流量快速建压,释放能量后,液压泵需要在一个周期内为蓄能器补充0.25 L液压油;为保证压力升率,系统最低流通能力为250 L/min。依据仿真结果选择系统关键元器件搭建脉冲试验台,试验台实现峰值压力42 MPa、升率1 100 MPa/s的T形波,并稳定持续20万次脉冲,验证了仿真分析的正确性。     

EHA作动器建模与仿真分析

电静液作动器(EHA)能够实现故障安全,不存在机械卡死等,在大功率的场合功重比优势明显,因此可应用到飞机主舵面的伺服控制系统中。介绍EHA的组成、工作原理和功能组件的作用,详细推导了EHA伺服作动系统三环闭环控制情况下的数学模型,并在此基础上进行频域分析,设计伺服回路参数,在AMESim仿真平台上搭建了EHA伺服作动系统的仿真模型。利用推导的EHA数学建模方法可实现EHA作动伺服回路参数的设计,同时还可实现EHA作动器关键参数敏感度分析;利用给出的仿真分析方法可在EHA设计初期验证EHA伺服作动系统的性能,为作动器的实物设计提供理论基础。