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单相升压型APFC电路的研究_电气工程论文范文
电气工程论文 摘 要 近年来，电力电子装置在军事、工业、农业、生活及高新技术领域的应用日趋广泛，电力电子技术已成为工程技术领域的关键技术之一。然而电力电子产品的广泛应用，对电网造成了严重的谐波污染,功率因数校正技术（Power Factor Correction）是电力电子产品满足绿色环保要求的必需手段，是未来开关电源发展的关键技术之一。 本文对Boost型APFC电路的功率因数校正技术进行了分析和研究。首先，主要介绍了功率因数（PF）的基本概念和PFC的发展和国内外科研动态,并说明了本文研究的主要内容。其次简单地介绍了无源功率因数校正技术,详细地说明了有源功率因数校正技术的基本工作原理, APFC的主电路拓朴及其控制方式和PFC电路的性能比较。接着，进行BOOST拓扑分析,讲述了在CCM控制方式下工作模式,设计了Boost AFPC整体电路的结构框图。再接着，给出了给出了主电路参数的计算过程及结果,主要包括升压电感、输出电容和功率器件。然后就着，先介绍APFC控制常用的专用集成芯片UC3854的内部结构及其工作原理,再是给出了控制电路参数的计算过程及结果,包括乘法器的设置、振荡频率的确定、峰值电流限制、驱动电路的设计和反馈补偿网络的初步设计。最后,第六章为全文小结，总结了本文的研究内容,并提出了进一步工作的设想。 关键词 谐波,有源功率因数校正，Boost变换器，电感电流连续模式,UC3854 目 录 1 绪论…………………………………………………………...............1 1.1 功率因数校正(PFC)问题的提出...…………………………………………..1 1.2 功率因数（PF）的基本概念………………………………………………….2 1.3 PFC的发展和国内外科研动态………………………………………………..4 1.4 本文研究的主要内容…………………………………………………….......5 2 功率因数校正技术………………………………………………...........6 2.1 无源功率因数校正……………………………………………………............6 2.2 有源功率因数校正……………………………………………………………6 2.2.1有源功率因数校正的基本原理……………………………………………6 2.2.2 APFC的主电路拓扑……………………………………………………..7 2.2.3 APFC的控制方法………………………………………………………..8 2.3 PFC电路的性能比较…………………………………………………………10 3 Boost型 APFC电路结构………………………………………………...13 3.1 BOOST拓扑分析……………………………………………………………….13 3.2 在CCM控制方式下工作模式的分析……………………………………………14 3.3 CCM状态下的电流正弦化……………………………………………………...15 3.4 Boost AFPC整体电路的结构框图……………………………………………...16 4 250W APFC电路设计……………………………………………………..18 4.1 主电路设计 18 4.1.1 升压电感的设计……………………………………………………………..18 4.1.2 输出电容的选择……………………………………………………………..20 4.1.3 功率器件的选择……………………………………………………………..21 4.2 控制电路设计………………………………………………………..23 4.2.1 UC3854简介………………………………………………………………..23 4.2.2 乘法器的设置………………………………………………………………26 4.2.3 振荡频率的确定…………………………………………………………….28 4.2.4 峰值电流限制………………………………………………………………28 4.2.5 驱动电路的设计…………………………………………………………….29 4.2.6 反馈补偿网络的初步设计…………………………………………………...29 4.3 试验结果及分析………………………………………………………………...30 5 结论…………………………………………………………...................32 致谢…………………………………………………………………………33 参考文献…………………………………………………………………….34 附录A( 250W样机电路原理图)………………………………………………………36 Abstract In recent years, Power electronic devices are wildly used in the military, industry, agriculture, life and high-tech applications, and power electronics has become one of the key technologies in the field of engineering. But due to wide applications of the electronic products, serious harmonic waves are produced. Now power factor correction has become one of necessary means which can satisfy the requirements of environmental protection. It is one of the key technologies in the future development of switching. In this paper, Boost circuit for APFC had been analyzed in detail. First, the paper is the Introduction of this paper and mainly introduces the basic concept of PFC, the development of Power Factor, scientific research at home and abroad and the main content of this paper. Second, it briefly introduces the passive power factor correction, then it describes the fundamental principle of the APFC in detail, the control methods, the main circuit topology of APFC, and compares the performance of PFC circuit. Third, it analyzes BOOST topology, describes in the control work patterns of CCM, then designs the overall structure of the Boost AFPC circuit. Fourth, it presents the calculated process of the main circuit’s parameters and results, which mainly includes boost inductor, the output capacitor and power devices. Fifth, it explains the interior structure and working principles of the integrated chip-UC3854 which is commonly used in APFC control, then presents the calculated process of the controlled circuit’s parameters and results, which mainly includes the multiplier’s settings, the oscillation frequency identification, the peak current limit, the design of dynamic circuit and feedback the preliminary design of the compensation network. Finally, Chapter 6 summarizes the full text, sums up the contents of this paper, and puts forward the idea of further work. Key words Harmonic, Active Power Factor Correction（APFC）, Boost Converter, CCM, UC3854
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三菱IPM驱动板的设计和实现_电气工程论文范文
电气工程论文 摘 要 随着电力电子技术的发展，功率器件在不断地更替。从结型控制器件，如晶闸管、GTR、GTO，到场控器件，如功率MOSFET、IGBT、IGCT,他们的体积不断地缩小，功率不断地提高，电气特性越来越优化，使得基于它们生产出来的产品，外观和性能都得到了很大改善。IPM智能功率模块是一种新型功率开关器件，是以ＩＧＢＴ为基本功率开关元件构成三相逆变器的专用功能模块，它继承了GTR和MOSFET的优点，其最大特点是集功率变换、驱动保护电路于一体。提高了系统的可靠性，使用起来十分方便。本文设计是以三菱公司的IPM—PM50CLA120例，用PROTEL软件来设计它的驱动板的原理图和PCB图。然后再做出驱动板的实物。用该驱动板去驱动IPM—PM50CLA120，以使三相异步电机在IPM—PM50CLA120的驱动下运转。再输入SPWM信号，测试IPM的驱动驱动信号的波形和三相异步电机的电流波形。实验证明驱动板能较好地工作。 关键词：智能功率模块、驱动板 目 录 摘要…………………………………………………………………………….…………….…… I 1 前言……………………………………………………………………………………………. 2 2 智能功率模块…………………………………………………………………………………3 2.1 IPM的内部结构……………………………………………………………….………...4 2.2 IPM的性能特性……………………………………………………………………...….4 2.21 IPM的优点 … ………………………………………………………………...5 2.2.2 IPM的额定值和特性 ………………………………………………………...6 2.2.3 IPM 的安全工作区 ……………………………………………………………7 2.2.4 IPM的自保护功能 ………………………………………………………….10 2.3 IPM的发展和应用…………………………………………………………………….11 2.3.1 IPM的发展 ……………………………………………….…………………..12 2.3.2 IPM的应用 …………………………………………………………………...12 3 智能功率模块的驱动板设计………………………………………………………………13 3.1 IPM的驱动原理……………………………………………………………….……….14 3.2 用Protel设计IPM的驱动板…………………………………………………………....15 3.2.1 驱动板原理图的设计…………………………………………………………..17 3.2.2 驱动板PCB图的设计………………………………………………………….19 4 智能功率模块的驱动测试………………………………………………………………….20 4.1 驱动测试说明…………………………………………………………………………….20 4.2 输入信号PWM简介……………………………………………………………………..21 4.3 驱动测试的波形………………………………………………………………………….24 5 总结…………………………………………………………………………………………..25 致谢……………………………………………………………………………………………….26 Abstract With the development of power electronics, power devices continues to change. From the node control device, such as Thyristor, GTR, GTO, to the scene controller devices, such as power MOSFET, IGBT, IGCT, their size are reducing ,and power are continuing to increase, becoming more and more optimize electrical characteristics, making them based on production out of products, the appearance and performance have been greatly improved. Intelligent Power Module IPM is a new type of power switching devices, based on IGBT power switching components for the basic three-phase inverter constitutes a special function module, it inherits the advantages of GTR and the MOSFET, and its most prominent feature is a power transformation, drive protection integrated circuit. Improved the reliability of the system is very convenient to use. In this paper, the design is based on Mitsubishi IPM-PM50CLA120 cases PROTEL software used to design the driver board schematic and PCB Fig. Driver board and then make the kind. Use this board to drive plate IPM-PM50CLA120, to enable the three-phase asynchronous motor in the IPM-PM50CLA120 driven operation. Then input SPWM signal , test the drive signal waveform of IPM and three-phase asynchronous motor’s current waveform. Driver board can be proved to work well. Keywords：Intelligent power module、 the drive plate
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6kV变电所设计_电气工程论文范文_电气工程论文
电气工程论文 目 录 摘 要II AbstractIII 1 绪 论1 2 参考资料及其分析2 2．1 原始资料2 2.1.1厂区平面布置图2 2.1.2负荷资料3 2.1.3供电协议3 2.1.4供电系统技术数据3 2.1.5本厂负荷性质3 2.1.6本厂自然条件3 2．2 设计范围、内容及其步骤4 3 全厂负荷统计5 3．1 负荷计算5 3．2 无功功率补偿7 4 各子变电所变压器的型号进行初选9 5 拟定全厂配电系统草图11 6 短路电流计算12 6．1 计算短路电流的目的12 6．2 短路电流计算12 6.2.1计算方法12 6.2.2计算步骤12 7 高低压设备选择17 7．1 高压设备选择的原则17 7.1.1高压开关柜的选择原则17 7.1.2短路校验的原则17 7．2 各部分高压开关柜的型号选择17 7.2.1 6Kv侧开关柜的选择17 7.2.2 车间变电所出线开关柜的选择17 7.2.3 避雷装置开关柜的选择17 7．3变电所一次设备的选择与校验18 7.3.1 380V侧一次设备的选择与校验18 7.3.2 6kV侧一次设备的选择与校验19 8 高低压线路选择20 8.1 线路选择与校验的项目及条件20 8.2 高低压母线选择20 8.3 6kV高压出线线路的选择与校验20 8.3.1选择校验的方法20 8.3.2按发热条件选择6kV高压出线21 8.4 各车间用电设备导线选择21 9 继电保护设置23 9.1 车间变压器的继电保护装置23 9.2 6kV母线断路器的保护24 9.3 6kV出线各支路的保护24 9.4其它各线路保护整定计算24 10 防雷与接地设计25 10.1 变电所的防雷保护25 10.1.1 电力线路的防雷措施25 10.1.2 变配电所的防雷措施25 10.1.3 雷电侵入波的防护26 10.2 变电所公共接地装置的设计26 10.2.1 接地电阻的要求26 10.2.2 接地装置的设计27 11 绘制总变电所供电系统全图28 12 总 结29 致 谢30 参考文献31 摘 要 本次设计主要围绕着变电所的电气设计展开，结合原始资料，完成变电所设计的各个步骤，主要包括：全厂负荷统计；高压进线选择；选择车间变电所变压器台数及其容量；拟定全厂配电系统草图；短路电流计算；高、低压配电装置选择；高、低压出线选择；继电保护装置设置及其整定计算；防雷与接地设计；绘制总变电所供电系统全图。本着以人为本的宗旨，追求变电所的运行具有可靠性，安全性，灵活性，经济性。通过对课题的完成，在设计过程中增进对供电工程，电力系统课程的理解和掌握运用，达到在实践中完善自我，丰富知识，巩固专业的目的。 关键词 6kV变电所；电气设计；电气设备选择；继电保护 Abstract The design mainly starts with the electrical design of electrical substation , combining with raw data, then complete the steps of substation design, including: full factory load statistics; high pressure into the line of choice; choose the number and capacity of substation transformers ; drawn sketch the whole plant distribution system; short-circuit current calculation; high and low voltage distribution equipment selection; high and low outlet options; protection devices to set their calculation; lightning protection and grounding; draw total electricity substation system-wide plan. In people-oriented objectives, the operation of substation requires reliability, security, flexibility and economy. Through the completion of the subject, to enhance the power supply works, power systems understanding and mastering the application of course in the process of design, to the practice of self-development, a wealth of knowledge, the purpose of consolidating the profession. Keywords 6kVsubstation；Electrical Design；Electric Equipment Selection；Relaying protection
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假日宾馆10KV变电所扩容工程设计_电气工程论文
电气工程论文 目录 摘要 I Abstract II 1 前言1 1.1 工厂变配电所的设计1 1.1.1 用户供电系统1 1.1.2 工厂变配电所的设计原则1 1.2 课题来源及设计背景2 1.2.1课题来源2 1.2.2设计背景2 2 变电所负荷计算和无功补偿的计算3 2.1变电站的负荷计算3 2.1.1负荷统计3 2.1.2负荷计算3 2.2 无功补偿的目的和方案5 2.3 无功补偿的计算及设备选择5 3 变电所变压器台数和容量的选择8 3.1 变压器的选择原则8 3.2 变压器类型的选择8 3.3 变压器台数的选择8 3.4 变压器容量的选择9 4 主接线方案的确定11 4.1 主接线的基本要求11 4.1.1安全性11 4.1.2可靠性11 4.1.3灵活性11 4.1.4经济性11 4.2 主接线的方案与分析11 4.3 电气主接线的确定12 5 短路电流的计算14 5.1 短路电流及其计算14 5.2 高压电网三相短路计算14 5.3 低压电网三相短路计算16 6 变电所高压进线、一次设备和低压出线的选择20 6.1 用电单位总计算负荷20 6.2 高压进线的选择与校验20 6.2.1架空线的选择20 6.2.2电缆进线的选择20 6.3 变电所一次设备的选择21 6.3.1高压断路器的选择21 6.3.2高压隔离开关的选择22 6.3.3高压熔断器的选择23 6.3.4电流互感器的选择23 6.3.5电压互感器的选择25 6.3.6高压开关柜的选择26 6.4 低压出线的选择26 6.4.1低压母线桥的选择27 6.4.2低压母线的选择27 7 变电所继电保护的选择与整定28 7.1 继电保护的选择与整定28 7.1.1继电保护的选择要求28 7.1.2继电保护的装置选择与整定28 8 变电所防雷与接地方案的设计34 8.1 确定共用人工接地装置34 8.2 防雷保护的选择34 9 备用电源自动投入装置36 9.1 备用电源自动投入装置的作用与类型36 9.2 对备用电源自动投入装置的基本要求36 9.3 备用电源自动投入装置的选择36 结 束 语38 参 考 文 献39 致 谢40 附录1 变电所一次系统图41 附录2 变电所低压配电图42 附录3 变电所平面布置图43 摘 要 变电所是电力系统的一个重要组成部分，由电器设备及配电网络按一定的接线方式所构成，他从电力系统取得电能，通过其变换、分配、输送与保护等功能，然后将电能安全、可靠、经济的输送到每一个用电设备的转设场所。变电所涉及方面很多，需要考虑的问题多，分析变电所担负的任务及用户负荷等情况，选择所址，利用用户数据进行负荷计算，确定用户无功功率补偿装置。同时进行各种变压器的选择，从而确定变电站的接线方式，再进行短路电流计算，选择送配电网络及导线，进行短路电流计算。选择变电所高低压电气设备，为变电所平面及剖面图提供依据。本变电所的初步设计包括了：（1）总体方案的确定（2）负荷分析（3）短路电流的计算（4）配电系统设计与系统接线方案选择（5）继电保护的选择与整定（6）防雷与接地保护等内容。 关键词： 变电所；负荷；输电系统；配电系统 Abstract The substation is an importance part of the electric power system, it is consisted of the electric appliances equipments and the Transmission and the Distribution. It obtains the electric power from the electric power system, through its function of transformation and assign, transport and safety. Then transport the power to every place with safe, dependable, and economical. The region of factory effect many fields and should consider many problems.Analyse change to give or get an electric shock a mission for carrying and customers carries etc. circumstance, make good use of customer data proceed then carry calculation, ascertain the correct equipment of the customer. At the same time following the choice of every kind of transformer, then make sure the line method of the transformer substation, then calculate the short-circuit electric current, choosing to send together with the electric wire method and the style of the wire, then proceeding the calculation of short-circuit electric current. This first step of design included:(1) ascertain the total project (2) load analysis(3) the calculation of the short-circuit electric current (4) the design of an electric shock the system design to connect with system and the choice of line project (5) the choice and the settle of the protective facility (6) the contents to defend the thunder and protection of connect the earth. Keywords：substation；load；transmission system；power distribution system
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德清民乐小区供电系统设计_电气工程论文范文
电气工程论文 摘要 本设计说明书是以德清民乐小区的变配电所为主体进行设计的。通过对设计原始资料的分析，住宅小区负荷的计算短路计算，选择相应的主变压器台数和容量，从而确定其具体的供电系统。再对其初选的系统进行相应的短路计算和高低压设备的选择及校验，选择和校验高低压线路。结合课本的基础知识，根据我国变配电所的运行情况以及各种电气设备的标准，进行具体的电气设备，达到安全用电和节约能源的目的，另外得出该住宅小区供电系统的线路图。本设计严格遵循变电所电气部分的设计原则。 通过本次毕业设计，巩固了供电系统的设计，熟练运用四年以来学过的知识，锻炼并提高了独立分析和解决问题的能力，也培养了对大学四年所学知识的综合应用。 关键词：小区供电 配电系统 负荷计算 目 录 摘要………………………………………………….…………………………. . .………..…...Ⅱ Abstrcat……………………………………………….……………………………………..…..Ⅲ 1 前言……………………………………………….……………………………………….....1 1.1 本课题研究的目的及意义…………………….……………………………………………1 1.2 供电系统的现状与未来发展………………….…………………………………………....1 1.3 本文的设计依据……………………………….……………………………………….…...2 1.4 本文所做的主要工作………………………….……………………………………..……..2 2 民乐小区供电系统总体方案及要求………….………………………………..……...3 2.1 民乐小区工程概况…………………………….……………………………………………3 2.2 供配电要求概述……………………………….…………………………………………....3 2.3 主接线方案的确定…………………………….……………………………………….…...5 3 民乐小区负荷计算及变压器选择…………….………………………….……..……...9 3.1 负荷计算原始资料…………………………….……………………………………………9 3.2 小区供电负荷计算…………………………….…………………………………………..10 3.3 变压器的选择………………………………….…………………………………………..16 4 民乐小区短路计算………………………….……...…………………….…..……….….17 4.1 短路计算的目的及方法………………….………………………………………………..17 4.2 短路计算……………………………….………………………………………………......17 5 民乐小区一设备的选择与校验…….…………………..………………………....…..21 5.1 一次设备选择与校验的条件及项目………………….……………….………….….…...21 5.2 一次设备的选择与校验………………….……………….………………….……….…...22 6 民乐小区输电线路选型……………………………………..………….……………....25 7 民乐小区照明系统设计…………………………………………………………..….…28 7.1 照明设计的一般规定……………………………………………………………...…...…28 7.2 本设计的具体设计方案…………………………………………………………….…….29 8 民乐小区接地与防雷设计……………………………….………………………….…30 8.1 接地与防雷概述……………………………………………………………………..……30 8.2 接地与防雷设计方案...……………………………………….…………………………..32 9 总结…………………………………………………………………….…………..……....33 致谢……………………………………………………………………………….…....…….....34 参考文献………………………………………………………………………..….……..……35 Abstract The design specification is based on folk music Deqing area for the variable distribution of the main design. Through the design analysis of raw data, the calculation of residential quarters load short-circuit calculation, select the appropriate and the number of main transformer capacity, in order to determine the specific power supply system. Primary system and then its corresponding short-circuit calculations and the choice of high and low voltage equipment check, selection and validation of high low-voltage lines. Combined with the basic knowledge of textbooks, according to our country by changing the operation of distribution and a variety of electrical equipment standards, electrical equipment specific to the security of electricity and energy savings, and come to the residential quarters of the line power supply system Fig. Strictly follow the design of electrical substation design principles. Graduated through the design, the consolidation of the power supply system design, training and increased the independent analysis and problem-solving skills, also trained by four years of university the comprehensive application of knowledge. Key word: Cell Power Supply，Distribution System，Load Calculation
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拉力测试系统软件设计_电气工程论文范文
电气工程论文 摘 要 随着科学技术的发展，对数据的准确度有越来越高的要求。以前的拉力测试主要是用人来测量。但是在测量当中经常会出现受力的不均衡，次数计算的错误等问题。这些导致数据的结果出现很大的误差，使产品质量出现很大的问题。目前国内相应的测试设备智能化、自动化程度不高，为此需要一体化智能型拉力测量试验仪。 论文讨论了拉力检测的原理，设计了拉力测试系统。设计出基于松下(Fp∑-c32)PLC，Proface触摸屏(GP37W2)，压力传感器，步进电机的拉力测试系统，只要把待测绳索装上测试台，就能自动进行拉力测试试验。系统可以根据不同要求，改动实验参数，从而达到不同的目的。本设计还采用了触摸屏作为人机界面，通过触摸屏的操作可进行参数设置，实现对各种功能的控制，同时还能通过触摸屏显示测试结果和对系统当前运行状态进行实时的监控。 关键词:拉力测试;PLC;步进电机;触摸屏 目 录 摘要……………………………………………………………………………….……………….. Ⅰ 1 前言…………………………………………………………………………………………... …1 1.1引言………………………………………………………………………………………. ...1 1.2拉力测试的现状和发展趋势……………………………………………………………. .. 1 2 总体设计方案…………………………………………………………………………………. 2 2.1 控制器…………………………………………………………………….…………... ….2 2.2 电动机的选择……………………………………………………………………........ ….2 2.3 传感器的选择 …………………………….…………………………………...……. …3 2.4 总体设计方案 ………………………………………………………………………. . ..4 3 PLC介绍…………………….………………………………………………………….... .. .. 5 3.1 PLC的发展概述…………………………………………………………….………..... .....5 3.2 PLC技术在步进电机控制中的发展状况…………………………………………...... .. ..5 3.3 FP∑-C32系列PLC…………………………………………………………………….. …6 3.4脉冲的控制…………………………………………………………………………….. … 8 3.5数据采样的实现……………………………………………………………………….. … 9 4软件设计……………………………………………………………………………………. …. 10 4.1 PLC编程介绍……………………………………………………………………….. …. 10 4.2 指令介绍…………………………………………………………………………….. ….10 4.3 PLC程序编写……………………………………………………………………….. ….. 16 4.4 触摸屏界面设计…………………………………………………………………….. …. 21 5 结束语…………………………………………………………………………………………… 28 致谢…………………………………………………………………………………………..... … ..29 参考文献……………………………………………………………………………… ..30 Abstract With the development of science and technology, the accuracy of the data to have higher requirements. The tension test is mainly used to choose and employ persons. But often appear in the measurement of the unbalanced force ，calculation error number and so on. These data results appear much error, make product quality problems appeared. At present domestic corresponding testing equipment, intelligent, automation degree is not high, therefore, it is necessary to measure tensile test instrument integrated intelligent. The paper discusses the principle, design tension test the tensile test system. Panasonic (Fp is designed based on PLC∑ - c32) screen (GP37W2), Proface pressure sensor, stepping motor tensile test system, as long as the rope on one measure, it can automatic tension test test. According to the different requirements, the system can alter experimental parameters, so as to achieve different purposes. This design is also used as a touch screen man-machine interface, through the operation parameters can be set to realize control, also can pass the screen test results of the system and the real-time monitoring. Keywords: tension tests;PLC;stepping motor ;touch screen
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10KV变电站继电保护系统设计_电气工程论文范文
电气工程论文 摘 要 本次设计的主要任务是为某工厂10KV变电所继电保护总体设计。该系统为 10kV电源进线，经过主变压器降压成380V后输送到各车间变电所，供给各车间使用。经过对基础设计资料的分析后，发现各个车间设备大都是三级负荷，只有小部分为二级负荷，因此，经过计算，并查阅了很多相关资料，最后选择了一台 1000kVA的主变压器，主变压器到各车间采用单母线进线方式。各个车间的接线采用放射式的接线方式。根据计算电流，选好各个设备，并通过短路电流、电压损失等进行校验和整定，然后做好继电保护系统及其校验，最后确定设计，拟定供电系统图。 关键词：供配电、负荷计算、短路电流计算、继电保护 目 录 摘要……………………………………………………………………………. . .……………. Ⅰ Abstract……………………………………………………………………………..Ⅱ 1 前言…….……….………………………………………………………………….…….….…1 2 设计原始资料 ……………….……………….…………………… …………….….….… 4 2.1 主体设计依据 ……………… …… ………………………… …………….….….……4 2.2 本厂自然条件 ……….……… …… ………………………… …………….……….…4 2.3 供电协议 ………………………….….………………………… ………….…….…… 4 3 负荷计算和无功功率补偿 .….………………………………… … ………….….….…7 3.1 负荷计算 ….…….……….…………………………………… … ………….….…. .….7 3.2 无功功率补偿 … …………………………………………… … ……….….….…….…9 4 变压器选择………………………………………………………………….…….….….…10 4.1 变电所主变压器方案选择 ……………………………… … ………….…….….….… 10 4.2 变压器方案选择比较 …………………………………… … ………….…….….….… 10 5 短路电流计算.….…….…….…………….………….……….…….… ………….….….…11 5.1 绘制短路计算电路 ……………………………………… … ………….…….….….…11 5.2 计算k-1点的短路电路总阻抗及三相短路电流和短路容量……….……….….….… 12 5.3计算k-2点的短路电路总阻抗及三相短路电流和短路容量….…….……….….….… 12 5.4 10kV侧一次设备选择校验 ……………………………… … ………….…….….….…14 5.5 380V侧一次设备选择校验 ……………………………… … ………….…….….….… 15 5.6 高低压母线选择…………………………………………………………….….….….… 16 5.7 变电所进出线及与邻近单位联络线选择………………………………….….….….… 16 5.7.1 10kV高压进线和引入电缆选择…………………………………….….….….… 16 5.7.2 380V低压出线选择 ……………………………… … ………….….….….… …17 6 继电保护及整定计算….…….…….……………………………………………….….… 21 6.1 变电所二次回路方案选择与继电保护的整定 ….……………………….….….….… 21 6.2 变电所的保护装置………………………….………………………………….….….… 21 6.2.1主变压器的继电保护装置….….……….………………………………….…..… 21 6.2.2备用电源的高压联络线的继电保护装置 …………………………….….….…24 6.2.3断路器控制回路和信号装置选择 ………….………………………….….….… 24 6.2.4 变电所低压侧保护装置…………………….……….………………….….….…25 7 变电所的防雷保护与接地装置设计 .….……………………………………….….…32 7.1 变电所的防雷保护 ……………………………………….………………….….….…32 7.2 变电所公共接地装置设计…………………………….………………….…….….….…32 8 总结……………………………………………………………….….…………….….……. 33 致谢……….…….………….…….…………….………………………………. . .…………….34 参考文献 ….…….……………………………………………………………. . .…………….35 附录 总变电所供电系统全图……….…….…………………………. . .…………………36 Abstract The design of the main tasks is a electrical plant distribution system design’ current protection. The high voltage 10 kV line was into the mill of the substation. The power was supplied to the workshop, which was transformed to 10 kV through the main transformer and transformed it into 380V. After the basis for the design of the data analysis, found that all workshop equipment are three class load, only a small part of the two class load. Through calculating and looking up a lot of relevant information, finally, the main transformers of 1000 kVA was chose. The line of main transformer to workshop is the single-bus line. According to the computation electric current, chooses each equipment, check and setting calculation through the short-circuit current and the voltage loss .and completion the relay protection system and the setting calculation, finally finish the design, working out the power supply diagram. Keywords：power supply system、load calculation、short-circuit currents calculation method、current protection
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基于小波变换的电力电缆故障检测研究_电气工程论文
电气工程论文 目录 摘 要I AbstractII 目录III 1 绪论1 2 电力电缆故障分类4 2.1 电缆的组成结构4 2.2 形成电缆故障的原因分类4 2.2.1 机械损伤4 2.3 电力电缆故障分类6 2.3.1 按电缆的组成材料分类（物理属性）6 2.3.2 按电缆故障发生的原因分类8 2.3.3 按电缆的结构特性分类9 2.3.4 按电缆故障发生的部位分类9 2.3.5 按故障外表特性或人的直觉性分类10 2.3.6 按电缆损坏程度分类10 2.3.7 按电缆的耐压等级分类11 3 常见故障检测方法12 3.1 电缆故障点的粗测12 3.1.1 直流电桥法测量短路和接地故障12 3.1.2 脉冲反射法测量电缆故障16 3.2 电缆故障点的精测(定点)19 3.2.1 声测法19 4 小波分析理论24 4.1 小波变换的基本概念24 4.1.1 基本小波24 4.1.2 小波基函数25 4.1.3 连续小波变换25 4.1.4 离散小波变换26 4.2 常用小波函数26 4.2.1 Haar小波27 4.2.2 Daubechies(dbN)小波28 4.2.3 Coiflet(coifN)小波28 4.2.4 Symlets(symN)小波29 4.2.5 Mexican Hat(mexh)小波30 4.2.6 Meyer小波30 4.3 MATLAB算法30 4.4 小波变换模极大值与奇异性检测32 5 基于小波分析的电缆故障在线定位检测的设计与仿真35 5.1 基于小波的电缆故障在线定位系统描述35 5.1.1 小波分析在输电线路奇异点检测中的应用35 5.2 电缆故障在线定位系统仿真36 5.2.1 建立电缆故障系统模型36 5.2.2 电缆断路故障仿真模型37 5.2.3 断路故障的数据分析计算37 5.2.4 电缆短路故障仿真模型39 5.2.5 短路故障的数据分析计算40 6 总 结43 致 谢44 参考文献：45 摘 要 随着国民经济的快速发展，我国电力工业得到了迅猛发展。电网规模越来越庞大，城市配电网络结构日益复杂完善，电力电缆的应用日益增多，电力电缆故障也相应增多。而输电线路电压等级和输送容量的逐步提高使得输电线路故障对社会经济生活造成的影响和损失也越来越大。因此如何尽快探测故障点距离，尤其是如何快速准确地找出电缆故障点并尽快修复，对配电网运行维护人员来讲是一项颇为艰辛的任务。目前，线路保护己经进入微机保护时代，而小波变换作为新型的更有效的数学分析工具，己在电力系统中得到应用。 本文将采用小波变换快速算法对电力系统中故障信号进行分析、判断。仿真结果表明，这种算法能够准确及时判断故障，符合工程实时性的要求。和传统方法相比：利用了小波的带通滤波性质，减少了信号损失，简化了检测系统硬件电路。此方法实现容易，信号分析效果好。 关键词：小波分析、电力电缆、故障波形、检测波形 Abstract With the rapid development of the national economy, our national power industry also has been developing fast. The larger the size of the grid, the more complex and advanced the power distribution network, the larger the application of power cable, the more the power cable fault. The gradually improvement of the voltage classification of transmission line and the transmission capacity leads to greater influence and loss to the social and economic life caused by transmission line fault. Consequently, how to detect the point of fault as soon as possible, especially how to identify exactly and quickly repair the cable fault, is a rather difficult task for the operation maintenance personnel of power supply. At present, the railway protection is approaching into the microcomputer protection era, while wavelet transform, as the innovative and the most effective mathematical analysis tool, has been widely applied in the power system. This thesis is adopting the wavelet transform fast algorithm to analyze and judge the fault signal of power system. The emulation results show that this formula can judge and locate the fault precisely and timely, which conforms to the requirements of real-time project. Compare with traditional methods, this method uses the band-pass filter qualification of the wavelet, and decreases the signal loss, simplifies electrical circuit of detecting hardware system. This method is easy to accomplish and boasts a great effect of signal analysis. Keywords：wavelet analysis、 power cables、fault waveform、the waveform detection
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某工厂10KV变电所总体设计_电气工程论文范文
电气工程论文 目 录 摘要. . .. III AbstractIV 1 前言.1 1.1 课程的意义和目的..1 1.2电能的特点及工厂变电所的用.1 1.3 工厂供电的发展趋势.1 1.4工厂供电设计的要求. . ..2 2 原始资料.2 2.1 主体设计依据 2 2.2 本厂自然条件 .2 2.3 供电协议 . . . . . 3 3 负荷计算和无功补偿...4 3.1 负荷计算...4 3.2 无功功率补偿.6 4 变压器选择 . 7 4.1对于各车间变压器的初步选型 7 4.2 主变压器台数选择 . 8 5 拟定全厂配电系统草图 . 9 6 短路电流计算 . 6.1 绘制计算电路 10 6.2 确定基准值. 10 6.3 短路电路总电抗标幺值及三相短路电流和短路容量 10 6.3.1 k-1 点的短路电路总电抗标幺值及三相短路电流和短路容量 . 11 6.3.2 计算k-2 点的短路电路总电抗及三相短路电流和短路容量 . .12 6.4 低压侧短路电流 13 6.4.1 高压系统电抗 . . 13 6.4.2 变压器的阻抗 . 13 6.4.3 母线的阻抗 . ..13 7 选择 10KV 高压开关柜并做相关短路校验.14 8 高低压出线选择 15 8.1 对于10KV侧出线到配电箱的选择 .15 8.2 对到车间埋地电缆的选择 . 15 8.2.1 到 NO1 车间变压器埋地电缆的选择 15 8.2.2 到 NO2 车间变压器埋地电缆的选择 16 8.2.3 对于化工厂架空线的选型 .16 9 确定继电保护设置.17 9.1 继电保护设置的选择.17 9.2 整定动作电流 . . ..18 9.3 检查灵敏度 . 19 10 变电所的防雷保护与接地装置的设计..19 10.1 直击雷防护 . . 19 10.2 电侵入波的防护 . 19 10.3 变电所公共接地装置的设计 . 20 11 总结21 致谢22 参考文献23 附录 总变电所供电系统全图…24 摘 要 本次设计的主要任务是为某工厂10KV变电所总体设计。该系统为 10kV电源进线，经过主变压器降压 10kV 输送到各车间变电所，车间变电所再降压成 380V，供给各车间使用。经过对基础设计资料的分析后，发现各个车间设备大都是三级负荷，只有小部分为二级负荷，且与邻近的化工厂有联络线，因此，经过计算，并查到了很多相关资料，最后选择了两台 2000kV.A的主变压器，主变压器到各车间采用单母线进线方式。各个车间的接线采用放射式的接线方式。根据计算电流，选好各个设备，并通过短路电流、电压损失等进行校验和整定，最后确定设计完成，画好系统大图。 关键词：供电系统、负荷计算、短路校验、继电保护 Abstract The design of the main tasks is a electrical plant distribution system design. The high voltage 10 kV line was into the mill of the substation. The power was supplied to the workshop, which was transformed to 10 kV through the main transformer and transmitted to the workshop substation, then workshop substation transformed it into 380V. After the basis for the design of the data analysis, found that all workshop equipment are three class load, only a small part of the two class load, and with the nearby chemical plants have a contact line. Through calculating and looking up a lot of relevant information, finally, the main transformers of 5000 kVA was chose. The line of main transformer to workshop is the single-bus line. Various workshops wiring used radiation-Connection. According to calculate current., selected the right equipment ,then checked and drawn up through short-circuit current and voltage loss . Finally the final design was completed and a great map was drawn. Keywords： the power supply design、load calculation、check short-circuit、current protection
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测力传感器放大器设计_电气工程论文范文
电气工程论文 目 录 摘 要I AbstractII 1 绪论1 1.1 研究背景及意义1 1.2 本设计的要求和安排2 2 传感器3 2.1传感器分类3 2.2传感器的静态特性4 2.3传感器的动态特性4 2.4传感器的线性度4 2.5传感器的灵敏度5 3运算放大器6 3.1运算放大器的发展概况6 3.2 运算放大器发展的特点6 3.3 运算放大器发展的几个主要方向7 3.4 运算放大器的特点7 3.5 运算放大器的结构11 3.6 运算放大器的应用23 4MOS管的基本特性26 4.1 MOSFET的结构26 4.2 MOSFET的工作状态27 4.3 MOS管的小信号模型28 4.4 MOS管的噪声及对精度的影响31 5 测力传感器放大器设计33 5.1 稳压电源设计33 5.2 放大电路设计35 5.3电路板安装与调试 38 6 结论41 致谢42 参考文献43 摘 要 运算放大器广泛应用于各种模拟电路、数模混合电路中，而由于各自所用的目标电路不同，侧重的指标也有所差别。对国内外相关的研究动态进行了仔细的调研，分析了运算放大器的一些性能指标，仔细比较了各种实现电路的优缺点。在文献综述的基础上，设计了一种运用集成运放组成的放大电路，实现对测力传感器等的微弱电压信号的放大。并要求放大器的放大倍数可调，以实现对比较大的范围的被测信号的测量。测量放大器的前级采用差分放大，然后经过双端信号到单端信号的转换，并经比例放大器进行放大，从而实现对放大倍数的控制。 结果表明，所设计的测力传感器放大器基本满足指标要求。测试后的电路已应用于测力传感器放大电路中。 关键词：传感器、运算放大器、集成电路、高增益 Abstract Operational amplifier is widely used in all kinds of analog and mixed-signal circuit. There are many differences of focused performance because it is applied for differential circuit. According to the most recent research of relative field,the specification of the operational amplifier are discussed. All kinds of structure of low-votage op-amp were compared and analyzed. On the base of the structure of other papers, a circuit was designed, which primarily through the use of integrated operational amplifier circuit to enlarge the composition of measurement of the sensors weak voltage signal amplification, requiring a higher common mode rejection capability. So differential input is the measurement of the pre-amplifier, and then after a two-terminal signal to the single-ended signal conversion,and ultimated by the ratio of the amplifer amplification. The results demonstrate that the sensor amplifier satisfies the parameters set beforehand. After slight modification, this circuit has been successfully applied to capacitor accelemeter. Keywords：sensors、operational amplifier、integrated circuit、high gain
