阀芯限位电液数字阀控系统及位置精度控制研究

为了提高液压机用数字阀增量控制精度,提出了一种阀芯限位电液数字阀控系统.把电机旋转角转换成阀芯位移,根据脉冲信号频率与个数确定阀芯速度与位置,达到调控油液流量与方向的效果.对电液数字阀控系统的位置精度控制构建了仿真模型,之后利用该模型进行了控制过程的动态性能测试.仿真结果表明:电液数字阀导程依次为2 mm、4 mm与6...     

基于AMESim的液压同步阀仿真分析及结构改进研究

应用AMESim对同步阀建模、仿真、分析,在分析参数的基础上,通过优化设计,确定了一种改进尺寸的方案,并且对它进行仿真分析,着重分析了它的响应时间、速度同步误差以及压力损失等.从不同角度分析改进后的同步阀的实用性,结果表明,改进后的同步阀的结构尺寸大大地减小,并且能够满足实际工作要求.     

基于AMESim的双液压缸同步提升系统仿真分析

随着电液比例控制系统不断完善,液压同步提升以其简便快捷、安全可靠的技术在工程领域逐渐得到了广泛的应用.以双液压缸同步提升系统为研究对象,建立单液压缸电液比例系统的数学模型,推导系统闭环传递函数.在主从控制策略下,采用Ziegler-Nichols算法对PID参数进行整定,获得控制参数,实现双缸的同步提升控制,并通过AM...     

基于新型数字同步阀的液压同步系统研究

介绍了一种以新型数字同步阀为同步控制元件，运用模糊PID算法进行控制的液压同步系统。在建立系统数学模型基础上对系统动态特性进行了仿真，结果表明该系统具有良好的动态特性和较高同步精度     

SRT33矿用自卸车同步阀对制动性能影响的仿真研究

制动分泵抱死是气压制动系统常见的故障之一,以AMESim软件为研究手段,详细分析了同步阀对制动性能的影响,并提出了改进措施.     

多自由度机构系统动态仿真与性能分析

利用CAD软件UG和动力学分析软件ADAMS,建立了具有多自由度机构系统的框架式断路器多体动力学分析模型,并用实验对模型的有效性进行了验证.通过ADAMS对其动态仿真,获得了断路器机构系统的动态特性,包括运动学参数和动力学参数.分析了影响断路器开断特性的因素及其与主要结构参数、触头材料性能之间的关系.给出断路器性能与其主要影响因素之间关系的定量描述.研究及试验测试结果表明,实测与仿真结果吻合较好,为断路器产品创新提供了必要的理论依据和开发手段.     

一种新型同步阀的设计与分析

以薄壁小孔的流量特性为理论基础,设计并分析了一种新型同步阀。利用轴向缝隙式可变节流口直接调节同步阀流量,解决了传统同步阀的原理性分流精度误差,减小了阀的压力损失。对新型同步阀的结构和工作原理进行介绍,并通过MATLAB计算和AMESim仿真分析,证明该阀的同步精度不存在理论性误差,主要影响因素是液压基础件的精度;该阀在负载压差为30MPa时的同步误差小于0.3%,整体压力损失为(0.3~0.4)MPa,整体性能能满足现有工况的要求。     

带分流集流阀的同步液压驱动系统建模与仿真

以带分流集流阀的全液压平地机同步液压驱动系统为研究对象,利用AMESim仿真软件建立系统模型,并通过模拟全液压平地机的实际工况,获得在不同载荷下同步液压驱动系统驱动轮的同步性能和行驶系统对负载变化的响应速度情况.仿真结果表明:在不同频率的载荷下,系统均能保证左、右马达高精度的同步性,且系统的响应速度较快.     

风力机总体性能分析与仿真

采用叶素动量理论对风力机进行气动力的计算分析,用VC开发计算程序,将计算的气动载荷加载到风力机AD-AMS仿真模型上,在MATLAB/Simulink下建立风力机传动系统的仿真模型;将传动系统模型同ADAMS模型进行联合,实现对风力机系统总体性能的联合仿真.仿真数据同国际有名的风力机分析软件计算数据比较,结果表明,该联合仿真方法可以较好地模拟风力机的总体性能.     

Development of a flow control valve with digital flow compensator

Flow control valves typically use mechanical pressure drop compensator or dynamic flow meter to lessen the impact of pressure drop on outlet flow. However, there are some disadvantages, such as complex mechanical structure and small flow capacity. In this paper, a kind of digital flow compensator with bilinear interpolation algorithm is presented to compensate the pressure drop, in which the pressure drop and the desired outlet flow are the two input parameters. A two-stage proportional flow control valve with the proposed compensator is investigated. Pressure drop across the metering orifice of the valve is measured and fed back to the proposed compensator. If the detected pressure drop has deviated from the threshold, then the compensator will generate a compensation signal to adjust the poppet opening of the valve, which ensures that the output flow is independent of the pressure drop. Performances of the valve with the proposed compensator are investigated by simulation and experiment. Results show that it has a reasonable static control characteristics. In addition, there is no dead-zone in its steady flow curve; pressure drop have little impact on its output flow. Its dynamics will be affected by pressure drop and input voltage. Increasing pressure drop can improve system dynamics under constant input signal conditions. On the other hand, increasing input signal can shorten the poppet's closing time, but it will result in the longer opening time and the greater overshoot in the opening stage.     

Development of a digital control system for high-performance pneumatic servo valve

Pneumatic servo systems are used in many fields, such as pneumatic robot systems or vibration isolation systems. To improve the controllability of the pneumatic servo system, a higher performance servo valve is needed.In the present paper, a pneumatic spool type servo valve having an air bearing and a high-resolution position sensor was developed. We attempted to achieve high-frequency, high-accuracy flow rate control by digitization of the controller. We present herein a control algorithm for digital control of this valve.The characteristics of this valve were measured and the natural frequency of the valve was clarified to be up to 300 Hz. The spool position accuracy and the dynamic characteristics of the developed servo valve are greatly improved compared to existing valves.     

同等方式的比例同步控制系统设计

针对现有的双液压缸比例阀液压同步实验系统控制回路单一且大多基于主从方式进行随动控制以及两液压缸运动过程中回路相互影响降低同步精度的现状,进行了基于最新的电液比例技术的双液压缸同等方式控制同步方案整体详细设计,系统可在比例调速阀同步回路和比例换向阀同步回路之间快速切换,且双缸在液压回路和控制模式两方面实现独立。完成了同步系统运行参数的计算、元器件的选型,设计了专门的液压源和负载加载系统以及同步控制电气回路。     

汽车道路模拟系统的模糊自适应控制及仿真

以汽车道路模拟系统为研究对象,根据模糊控制理论,将模糊控制与常规的增量式PID控制相结合,设计出一套模糊自适应控制系统.并对C级路面谱进行仿真再现,仿真结果表明,该控制器比常规PID控制器具有更高的控制精度和更好的动态性能,在道路模拟仿真试验中可以达到非常满意的效果.     

转板式气动数字压力阀设计与仿真研究

随着数字化控制技术的快速发展,直接数字化控制是目前研究较多的一种针对数字/伺服阀控压力系统的控制方法。针对之前"气动阀多采用阀芯阀套结构、模拟量控制,对控制器要求高"的问题,提出了一种转板式气动数字压力阀结构。该气动数字阀采用步进电机加一块特殊形状的转板来实现对气动阀输出气压的控制,采用计算机直接控制方式,建立了气动数字压力阀的数学模型,并对其进行了仿真实验。实验研究结果表明,该数字阀气压输出、输入线性度高,利于开环控制。     

增量式数字阀的设计与分析

从实用角度出发,分别对增量式数字阀液压阀、机械结构三方面进行比较详尽的讨论。在保证应用性能的前提下尽可能降低设计、加工及元件采购成本的原则,研制出了一种结构简单、工作可靠、造价低廉的数字阀。     

水压数字节流阀微机控制的设计研究

介绍了水液压技术的概念及其特点，论述了直控步进式水压数字节流阀的工作原理及其控制系统的设计。利用步进电机接受微机控制，并驱动液压阀阀芯产生移动，从而改变节流口的通流面积进行流量调节，达到控制精度高的目的。     

在轨光学相机探测图像数字仿真系统设计与实现

根据在轨光学相机测量原理与工作环境,建立了空间目标相对运动学与反射光学特征模型、相机成像模型以及背景恒星成像模型;分析了相机测量噪声及相机探测灵敏度并在仿真中考虑了对干扰因素成像质量的影响,完成了现有星表中背景恒星的视星等根据相机的探测波段范围进行了仪器星等的等效计算,以提高仿真图像的逼真度;根据相机工作原理设计了仿真流程,应用Visual C++与Open GL技术完成了仿真软件的实现。     

Analysis and compensation for the cascade dead-zones in the proportional control valve

The four-way proportional directional control valve has been widely used as the main stage spring constant for the two-stage proportional control valve (PDV). Since a tradeoff should be made between manufacturing costs and static performance, two symmetry dead-zones are introduced in the main stage spring constant: the center dead-zone caused by the center floating position and the intermediate dead-zone caused by the intermediate position. Though the intermediate dead-zone is much smaller than the center dead-zone, it has significant effect on the dynamic position tracking performance. In this paper, the cascade dead-zones problem in a typical two-stage PDV is analyzed and a cascade dead-zones model is proposed for the main stage spring constant. Then, a cascade dead-zones inverse method is improved with gain estimation and dead-zone detection to compensate the dead-zone nonlinearity. Finally, a digital controller is designed for verification. The comparative experimental results indicate that it is effective to reduce the large position tracking error when the proposed method is applied.