It adopts pc computer control , the high accuracy force value sensing test system , step - motor direct driving ball threaded screw methods it may set arbitrary numbers for the parameters such as gripped sample length stress rate , test times etc . the testing results would be output in forms of chinese characters reporting statistics through the printer 采用pc机控制,高精度力值传感测量系统及步进电机直接驱动滚珠丝杆方式.对夹持试样长度.拉伸速度.实验次数等参数均能任意设定.测试结果由打印机输出
With the development of the ac servo system , there is a new electro - hydraulic servo system which is called direct drive electro - hydraulic servo system . this new system has many advantages such as better controlled ability , higher efficiency , smaller bulk , simpler construction and energy saving . so it is widely considered to be one of the most important developing directions of the hydraulic control system 随着交流伺服技术的发展,出现了一种新型的电液伺服系统? ?直驱式电液伺服系统,它具有电动机控制的灵活性和液压系统出力大的双重优点,具有高效节能、体积小、可靠性高等显著优点,被认为是液压控制系统的重要发展方向之一。
Recently , the renewable energy such as wind power have been strongly encouraged because of environmental problem and shortage of traditional energy sources in the near future . based on the tradional consrant speed constant frequency wind energy generation , this paper has a focus on the variable speed constant frequency wind energy convertion technonogy which using direct drive permanent magnet synchnonous generator and theory analysis and simulation are carried out in detail 当今对可再生能源的开发利用中,风能由于其突出的优点而成为研究的热点,风力发电是我国能源和电力可持续发展战略的最现实选择。目前各种风力发电技术的发展方兴未艾,而其中变速恒频风力发电技术因其高效性和实用性正受到越来越多的重视。
Through consulting lots of relevant references , present research of direct drive volume control hydraulic servo system is summarized in this paper , the principle and character of this system are expatiated , the principle of vector control is introduced . at the same time , the mathematical model of ac asynchronous motor is set up based on the vector control theory . the mathematical models of both the pump controlled motor and pump controlled cylinder are set up and simulated in this paper 在查阅大量国内外相关文献的基础上,本文综述了国内外对该系统研究概况,阐述了该类系统原理和特点;阐述了矢量控制的基本原理,并基于这一原理建立交流异步电动机的数学模型;分别建立了泵控马达系统和泵控缸系统的数学模型,并给出了仿真分析;设计了用于泵控马达系统的集成阀块,加工了密闭压力油罐;针对现有直驱式电液伺服装置所存在的问题,本文主要针对系统工作过程中所产生的噪音与爬行问题进行了一定的研究。
This is a newly introduced slight shocking , direct driving centrifugal hyro - extractor . the electric locomotive on its base is semi - closed , internal ventilating , self cooling , weight adding and energy saving . the internal drum and rotational drum are istalled on the axel of the locomotive and drived directly , which effectively decreases energyloss , and simplifies therotation . acontrolling box is used in the machine to start through frequency conversion . and stop through resistance . the showing board shows the rotation speed and adjusts the speed and time . the featues of this machine areenergy saving , durable and repair infrequent . this machine is spcially used for cloth hydroectraction 本机系最新引进直微震直驱式离心脱水机，它使用半封闭内通风自冷加重型专用节能电机装于中间底座，内桶及转鼓装于电机轴而直接驱动之，有效地减小了多功能损耗，简化了传统的多级繁琐转动，本机配有一个电控箱机变频起动，电阻刹车于一体面板有转速显示并可调速度及时间，该机特点省电、耐用、维修机会极少，本机适合布匹脱水使用。
On the basis of the magnetic circuit structure analysis for the particularity of the structure and the magnetic circuit of the double - stator hybrid direct drive motor ( dshbddm ) , the mathematical formula for the important parameters - self - inductance and mutual - inductance of the winding for dshbddm was derived in detail by using the method for the simplified magnetic network model and the characteristic was analyzed 摘要针对串联磁路结构双定子混合式直接驱动电动机结构和磁路的特殊性，在分析电机磁路结构的基础上，利用电机的简化磁网络模型，详细推导出串联磁路结构双定子混合式直接驱动电动机的重要参数绕组自感与互感的数学表达式，并对其特性进行了分析。
Ultrasonic motor ’ s vibration is excited by the conversely piezoelectric effect of piezoelectric materials . with the friction coupling , the rotation of the rotor or moving of the slider is generated . as a direct driving motor , it is becoming a hotspot in the field of mechanical and electrical control 超声波电机利用压电陶瓷的逆压电效应产生超声振动,并将这种振动通过摩擦耦合来直接驱动转子或滑块的运动,它作为一种直接驱动电机已成为当前机电控制领域的一个研究热点。
It adopts pc computer control , the high accuracy force # 118alue sensing test system , step - motor direct driving ball threaded screw methods it may set arbitrary numbers for the parameters such as gripped sample length stress rate , test times etc . the testing results would be output in forms of chinese characters reporting statistics through the printer 采用pc机控制,高精度力值传感测量系统及步进电机直接驱动滚珠丝杆方式.对夹持试样长度.拉伸速度.实验次数等参数均能任意设定.测试结果由打印机输出
First , variable speed constant frequency wind energy convertion theory is described in this paper , then presents a review on the development of wind turbines control and the main types of generator and static converters used to interface variable speed wind turbines to the electric grid . then discuss main circuit constructure and advantage of direct drive wind energy conversion system and introduce pitch - control method for wind power traction and electric power stability . simply aerodynamic characteristic of the turbine is analysised and permanent magnet synchnonous generator math model is established . to convert the variable frequency electricity into utility grid , back to back four - quadrant pwm - vsi is used and three typies of control strategy is presented to capture the maximum wind energy and transmit energy . then simulation is implemented to test the control strategy . in the following chapter a simple ac - dc - ac converter with a dc - dc boosting chopper is proposed to transmit the wind energy into electricity energy and two control strategy is presented 建立了永磁电机和变流器的数学模型,针对双pwm变频器的特点提出了三种控制策略对变流器进行控制,通过变流器交-直-交的变换,将发电机发出的变频变幅值交流电转化为可用的恒定频率的交流电,通过pwm调治能使其输出功率因数为一,并且该控制系统功率因数为可调,能在特殊情况下同电网交换一定的无功功率,并通过对变流器的控制实现了最大风能俘获的功能。最后采用matlab / simulink进行了仿真,取得了良好的仿真效果。在风力发电系统中,采用先进的最大功率俘获算法,能有效的从风中获得最大的能量。
