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1.
综述程控稳压稳流电源的发展状况,并介绍几种稳压稳流电源的基本原理及设计方法。在此基础上提出基于PIC16F84单片机及经典的线性反馈调整电路,提出一种可程控稳压稳流电源的设计方法,完成了原理图和PCB板的设计以及电路的调试与测试。经过测试表明,该系统具有可程控、输出电流大、输出电压范围广、电压电流稳定等特点,达到了设计预想要求。  相似文献   

2.
本文介绍利用Visual Basic 6.0设计PCS-05型程控直流恒流电源控制软件,以达到控制该电流源输出用户所需各种电流方波信号.  相似文献   

3.
基于单片机的高精度数字直流电流源设计   总被引:5,自引:3,他引:2  
本设计以单片机系统为核心,实现了直流电流源的程控电流输出。设计分电源,AD和DA转换,电流源输出,显示和控制模块。系统使用12位的AD和DA芯片,提高了输出电流的精度;输出模块引入PI控制器,有效控制了电路的非线性失真,输出电流无静差跟踪电流给定。实验结果表明:给定电流在20mA-2000mA内变化时,系统输出电流误差小于1mA,电流纹波小于0.2mA。  相似文献   

4.
飞机机载电源系统供电品质直接关系到飞机用电设备可靠工作和飞行安全,为此,2006年国际标准组织推出了新的机载电源标准ISO1540-2006;本文根据该标准要求,提出了一种机载电源的稳态和瞬态特性的测试的实用方法;建立了测量的数学模型;采用虚拟仪器技术,设计硬件测试平台,包括功率因数可调的大功率数字化程控负载和计算机数据采集系统;基于LabVIEW开发了测试软件;为满足暂态特性的测量要求和精度要求,采用了NI高速高精度数据采集卡,实现了较高的测量精度,综合测量误差小于0.5%,并在暂态测量中,考虑了负载接触器吸合时间;该测试系统可以用来检验恒频机载交流电源的特性是否符合国际标准要求,以保证飞行安全。  相似文献   

5.
透射电子显微镜透镜稳流电源的研究   总被引:1,自引:0,他引:1  
本文以物镜磁透镜稳流电源为例,介绍了透射电子显微镜透镜稳流电源的结构和工作原理.透镜稳流电源由前置高精度稳压电源模块、数模转换器、低漂移电压比较放大器、高精度恒温基准电压源、电流输出前置驱动、电流输出功率模块、基准电阻、输出电流检测模块等组成.通过检测基准电阻两端的电压并将其反馈到电压比较放大器形成对输出电流的闭环控制.达到对电流稳定度的要求.透镜稳流电源受计算机的控制,能接收稳流电流参数,并将电源的工作状态发送给计算机.实验结果表明该透镜稳流电源完全达到了设计指标,可以满足透射电子显微镜各级磁透镜的要求.  相似文献   

6.
设计了一款高精度、低纹波、稳定性高的程控直流电流源,它采用STM3 2 F103微控制芯片作为整机的控制核心,设计上位机软件来实现对硬件系统的调控。硬件系统由双闭环结构组成,内环是由PI控制器构成电压串联负反馈,提高了输出电流的稳定性。外环则是通过A/D采样电路将实际电流值送入主控芯片,再根据相应控制算法重新调整D/A的输出,提高了输出电流的精度。测试结果表明,电流源的输出电流稳定度高达0.003%,精度达0. 01%,最大输出电流高达25 A,适用于电力部门、计量院等对电源精度要求高的场合。  相似文献   

7.
在真空管的排气系统中,需要对真空管管体加热,并对其灯丝等设备提供一定的电压和电流.为了配合计算机控制的排气系统,需要采用程控电源仪提供所需的电压.本设计中的程控电源仪是一台实用化的电压调节智能仪表,它控制电机调节自耦变压器,通过反馈控制使其输出电压稳定在一个宽范围变化的电压值.它通过RS-485与串行通信电路与上位机连接,并且具有电流测量、报警输出等扩展功能.实际应用表明,该电源仪设计合理,工作可靠,性能稳定.  相似文献   

8.
以电磁感应发生系统为应用背景,设计实现一种可输出直流、交流电压的程控大功率数字电源。电源采用单相全桥主功率拓扑,以DSP作为控制核心,实现与上位机的交互和电源输出地灵活控制。直流输出采用电流闭环,交流输出采用电压前馈,以简单可靠的控制方式实现磁场电流的高精度控制。实际应用表明,该电源系统运行稳定,精度高,可操控性好。  相似文献   

9.
本文首先提出了强磁场电源电压参考源的设计要求即高稳定和可程控,然后在分析影响该电压参考源稳定度的关键因素的基础上选取了有效的数模转换芯片DAC1220和其基准电压源MAX6325,并给出了整个系统的硬件设计和各部分的软件设计,实验结果表明,数模转换输出能产生程序控制的按照设定斜率上升的电压曲线,并且在严格控制温度的条件下,设定值处能取得预期的8小时内良好的稳定性.  相似文献   

10.
基于PLC的机载电子设备ATE电源控制系统   总被引:1,自引:0,他引:1  
为了实现对某型机载电子设备ATE系统测试资源的有效管理,满足按照专业适配器分别自动程控上电的要求,采用了一种PLC和上位计算机组合控制模式,实现了PLC电源控制系统多路开关量TD按钮的单独控制和上位计算机的组态监控,并实现了两种控制模式的无痕迹切换;在此基础上,还设计实现了系统的电压、电流报警和系统内温湿度的空调控制;实践证明,实现的ATE电源控制系统,减少了资源的不合理使用,提高了资源的利用效率,提高了系统运行的可靠性。  相似文献   

11.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

12.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

15.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

16.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

17.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

18.
《计算机科学》2007,34(4):148-148
Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.  相似文献   

19.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

20.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

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