毕业论文-路灯控制器的设计24981.doc

浙 江 * * 学 院 毕业设计（论文）题目：路灯控制器的设计姓 名 :系 别、 专 业 : 导 师 姓 名、职 称 : 完 成 时 间 : 目 录引言一 方案论证 1.1引入路灯控制器的原理1.2光敏电阻调光电路 1.3光敏电阻式光控开关二 电路原理图设计 三 路灯控制器的硬件设计3.1路灯控制器的设计3.2器件的选择3.3电路的分析四 画出电路原理图五 总结与体会 六 参考文献 摘 要本实验的路灯控制器是由光敏元件，放大器，继电器，受控灯和电源电路组成，运用到了模拟电子技术中的多级放大电路。主要用于安装在公共场所或道路两旁的路灯通常希望随日照光亮度的变化而自动开启和关断，既满足行人的需要，又能节电。一些芯片和元器件的功能及其应用，以达到将理论知识学以致用、融会贯通的目的。关键词：继电器；光敏元件；关照变化；控制 如图所示是一个采用双向晶闸管制作的光控路灯电路，且它也采用二线制接法，所以安装比较简便。白天，光敏电阻器rl因受自然光线照射，rl呈现低电阻，它与r1分压后，获得的电压低于双向触发二极管vdh的折转电压，故双向晶闸管vth阻断，电灯e不亮。当夜幕来临时，rl上分得电压逐渐升高，当高于vdh的折转电压。1 方案论证随着能源问题越来越引起人们的重视，节能已经成为生产应用中不可忽视的一方面，路灯控制器主要用于安装在公共场所或道路两旁的路灯通常希望随日照光亮度的变化而自动开启和关断，既满足行人的需要，更重要的是它能节电。了解常用路灯控制的各种方法，及各自的优缺点，通过相互的比较，确定设计方案，并对所用传感器进行选型，同时加以电路的设计与分析，完成设计任务。下面的两个小节分别对路灯控制器的原理，路灯控制器中用到的主要元件以及在电路中的作用分析。1.1引入路灯控制器的原理此路灯控制器主要由光敏元件，放大器，继电器，受控灯和电源电路组成。继电器是一种当输入量（电、磁、声、光、热）达到一定值时，输出量将发生跳跃式变化的自动控制器件。在这个电路中随着光照的变化，继电器会相应的吸合或者断开，即决定路灯工作与否。白天，光照强度强，光敏电阻r2呈现低阻状态，vt1基极电位降低，vt1和vt2处于截止状态，继电器k不吸合，灯l不亮。当夜幕降临时，光照强度弱光敏电阻r2阻值逐渐变大，vt1基极电阻上升，当上升到一定程度后，vt1导通，vt2随之导通，继电器k吸合，灯l点亮。1.2光敏电阻调光电路当周围光线变弱时引起光敏电阻的阻值增加，使加在电容上的电压上升，达到增大照明灯两端电压的目的。反之，若周围的光线变亮，则光敏电阻阻值下降，照明灯两端电压也同时下降，使灯光变暗，从而实现对灯光亮度的控制。 图1 光敏电阻调光路1.3光敏电阻式光控开关以光敏电阻为核心元件的带继电器控制输出的光控开关电路有许多形式，在本实验中我用了简单的继电器开关电路。其工作原理是：光照下降到设置值时由于光敏电阻阻值上升激发导通，激励电流使继电器工作，常开触点闭合，常闭触点段开，实现对外电路的控制。图2 光敏电阻式光控开关电路2 电路原理图设计如下图设计的路灯控制器电路原理图，使此路灯控制器白天，光敏电阻r2呈现低阻状态，vt1基极电位降低，vt1和vt2处于截止状态，继电器k不吸合，灯l不亮。当夜幕降临时，r2阻值逐渐变大，vt1基极电阻上升，当上升到一定程度后，vt1导通，vt2随之导通，继电器k吸合，灯l点亮。图3 电路原理图3 路灯控制器的硬件设计3.1路灯控制器的设计路灯控制器主要由光敏元件，放大器，继电器，受控灯和电源电路组成。白天，光照强度强，光敏电阻r2呈现低阻状态，vt1基极电位降低，vt1和vt2处于截止状态，继电器k不吸合，灯l不亮。当夜幕降临时，光照强度弱光敏电阻r2阻值逐渐变大，vt1基极电阻上升，当上升到一定程度后，vt1导通，vt2随之导通，继电器k吸合，灯l点亮。电路图如下：图4 路灯控制器设计电路在这里继电器是一个主要的元件，继电器是一种当输入量（电、磁、声、光、热）达到一定值时，输出量将发生跳跃式变化的自动控制器件。继电器的输入信号x从零连续增加达到衔铁开始吸合时的动作值xx,继电器的输出信号立刻从y=0跳跃到y=ym,即常开触点从断到通。一旦触点闭合，输入量x继续增大，输出信号y将不再起变化。当输入量x从某一大于xx值下降到xf,继电器开始释放，常开触点断开。我们把继电器的这种特性叫做继电特性，也叫继电器的输入输出特性。释放值xf与动作值xx的比值叫做反馈系数，即 kf= xf /xx 触点上输出的控制功率pc与线圈吸收的最小功率p0之比叫做继电器的控制系数，即kc=pc/p0。图5 继电器的输入输出特性3.2器件的选择3.2.1ic7812电子产品中常见到的三端稳压集成电路有正电压输出的78系列和负电压输出的79系列。故名思义，三端ic是指这种稳压用的集成电路只有三条引脚输出，分别是输入端、接地端和输出端。它的样子象是普通的三极管，to-220的标准封装，也有9013样子的to-92封装。 用78/79系列三端稳压ic来组成稳压电源所需的外围元件极少，电路内部还有过流、过热及调整管的保护电路，使用起来可靠、方便，而且价格便宜。次此实践我采用ic7812稳压芯片。值得注意的是：注意三端集成稳压电路的输入、输出和接地端绝不能接错，不然容易烧坏。一般三端集成稳压电路的最小输入、输出电压差约为2v，否则不能输出稳定的电压，一般应使电压差保持在4-5v，即经变压器变压，二极管整流，电容器滤波后的电压应比稳压值高一些。3.2.21n4002几乎在所有的电子电路中，都要用到半导体二极管，它在许多的电路中起着重要的作用，它是诞生最早的半导体器件之一，其应用也非常广泛。二极管种类有很多，我们设计所用的二极管组就是其中的整流二极管。二极管按照所用的半导体材料，可分为锗二极管（ge管）和硅二极管（si管）。根据其不同用途，可分为检波二极管、整流二极管、稳压二极管、开关二极管等。按照管芯结构，又可分为点接触型二极管、面接触型二极管及平面型二极管。在此综合实践中，我用的是整流二极管。1n4002是一种整流二极管，它是利用二极管单向导电性，可以把方向交替变化的交流电变换成单一方向的脉动直流电。发光二极管（led）是用半导体材料制作的正向偏置的pn结二极管。其发光机理是当在pn结两端注入正向电流时，注入的非平衡载流子（电子空穴对）在扩散过程中复合发光，这种发射过程主要对应光的自发发射过程。按光输出的位置不同，发光二极管可分为面发射型和边发射型。我们最常用的led是 ingaasp/inp双异质结边发光二极管。3.2.3 发光二极管发光二极管的发光原理同样可以用pn结的能带结构来解释。制作半导体发光二极管的材料是重掺杂的，热平衡状态下的n区有很多迁移率很高的电子，p区有较多的迁移率较低的空穴。由于pn结阻挡层的限制，在常态下，二者不能发生自然复合。，而当给pn结加以正向电压时，沟区导带中的电子则可逃过pn结的势垒进入到p区一侧。于是在pn结附近稍偏于p区一边的地方，处于高能态的电子与空穴相遇时，便产生发光复合。这种发光复合所发出的光属于自发辐射，辐射光的波长决定于材料的禁带宽度eg。发光二极管具有可靠性较高，室温下连续工作时间长、光功率电流线性度好等显著优点，而且由于此项技术已经发展得比较成熟，所以其价格非常便宜。因此在一些简易的光纤传感器的设计中，如果led能够胜任，选用它作为光源即可大大降低整个传感器的成本。然而led的发光机理决定了它存在着很多的不足，如输出功率小、发射角大、谱线宽、响应速度低等。因此，在一些需要功率高、调制速率快、单色性好的光源的传感器设计中，就不得不以提高成本为代价，选用其它更高性能的光源。3.2.4光敏电阻由光敏电阻的工作原理是基于内光电效应。在半导体光敏材料两端装上电极引线，将其封装在带有透明窗的管壳里就构成光敏电阻如图所示。为了增加灵敏度，两电极常做成梳状。构成光敏电阻的材料有金属的硫化物、硒化物、碲化物等半导体。 半导体的导电能力取决于半导体导带内载流子数目的多少。当光敏电阻受到光照时，价带中的电子吸收光子能量后跃迁到导带，成为自由电子，同时产生空穴，电子空穴对的出现使电阻率变小。光照愈强，光生电子空穴对就越多，阻值就愈低。当光敏电阻两端加上电压后，流过光敏电阻的电流随光照增大而增大。入射光消失，电子-空穴对逐渐复合，电阻也逐渐恢复原值，电流也逐渐减小。3.3电路的分析。 利用光照强度为传感器，目前最为常用且性价比较高的就是光敏电阻，利用其光线较强时，电阻值较低，而光线较暗时则电阻较大的特点，利用电桥，可将光线信号转换成电信号，再通过电压比较器等方式，可以有效地完成控制需要。这类设计中，只要能将光线信号取出，整个设计也便完成了大半，至于控制部分的设计，可采用继电器输出，这样就算驱动较大的路灯负载，只需再加接触器便可完成。在本系统的设计中，如何提高系统在光线临界状态的稳定性，是设计的难点所在。由于光敏电阻的电阻值变化是连续的，因此在靠近临界点时，容易造成不稳定，在设计中若能用运放电路来完成处理，则可将运放接成电压比较器的方式，这样可以完成较为精确的起控；若采用分立元件来处理，可以采用稳压管来稳定工作点，只有当分压大于稳压管的击穿电压时，电路才能起控。声光控路灯控制器可以自动实现白天光线较暗和晚上遇到声响时，路灯自动点亮，从而实现人来灯亮，人走灯灭，既方便又实用。不仅节约了电能，而且能延长灯泡使用寿命。可广泛应用于楼梯，走廊，卫生间及生活小区等公共场所的照明控制。此控制器经济实用，即使一般的脚步声也能出灯泡发光照明好。四 画出电路原理图晶闸管路灯自动限压保护电路元器件列表元件名称元件参数r15.6kr22kr31.2kr40.1kr515kr62kr72kr81.5kr91.5kc1200uf 50vc20.47uf 63vrp16.8krp21k五.总结与体会 当今中国的老百姓越来越重视节约能源，这个电路就是为了节约更多的能源设计的。我国是一个资源大国，但最近这些年因为过度重视经济建设，在创造了许多财富的同时也消耗了很多能源。比如近些年来，每到夏天到来，就会有许多能源高峰期，政府也会采取一些相应措施限制人们用电。如果路灯控制器安装在公共场所或道路两旁的路灯通常希望随日照光亮度的变化而自动开启和关断，既满足行人的需要，又能节电。通过本次实验，使我明白了路灯控制器的工作原理。即当光照强度达到一定强度路灯控制器会相应的开启或关闭。达到了节能的目的，减少了不必要的浪费。在实际实践的过程中，我发现也有需要改进的地方，如：如何提高系统在光线临界状态的稳定性，是设计的难点所在。由于光敏电阻的电阻值变化是连续的，因此在靠近临界点时，容易造成不稳定，在设计中若能用运放电路来完成处理，则可将运放接成电压比较器的方式，这样可以完成较为精确的起控；若采用分立元件来处理，可以采用稳压管来稳定工作点，只有当分压大于稳压管的击穿电压时，电路才能起控。这样就解决了光照强度在靠近临界点是路灯控制器工作的。六.参考文献1电力电子变流技术 王廷才编 机械工业出版社2晶闸管变流技术应用图集 王文郁编 机械工业出版社3电力电子变流技术 曾芳编 西安电子科技大学出版社 4电类专业课程设计指导 张华编 机械工业出版 5电力电子技术应用电路 王文郁编 机械工业出版社ag an employment tribunal clai emloyment tribunals sort out disagreements between employers and employees. you may need to make a claim to an employment tribunal if: you dont agree with the disciplinary action your employer has taken against you your employer dismisses you and you think that you have been dismissed unfairly. for more informu, take advice from one of the organisations listed underfurther help. employment tribunals are less formal than some other courts, but it is still a legal process and you will need to give evidence under an oath or affirmation. most people find making a claim to an employment tribunal challenging. if you are thinking about making a claim to an employment tribunal, you should get help straight away from one of the organisations listed underfurther help. ation about dismissal and unfair dismissal, seedismissal. you can make a claim to an employment tribunal, even if you haventappealedagainst the disciplinary action your employer has taken against you. however, if you win your case, the tribunal may reduce any compensation awarded to you as a result of your failure to appeal. remember that in most cases you must make an application to an employment tribunal within three months of the date when the event you are complaining about happened. if your application is received after this time limit, the tribunal will not usually accept i. if you are worried about how the time limits apply to you if you are being represented by a solicitor at the tribunal, they may ask you to sign an agreement where you pay their fee out of your compensation if you win the case. this is known as adamages-based agreement. in england and wales, your solicitor cant charge you more than 35% of your compensation if you win the case.youre clear about the terms of the agreement. it might be best to get advice from an experienced adviser, for example, at a citizens advice bureau. to find your nearest cab, including those that give advice by e-mail, click onnearest cab.for more information about making a claim to an employment tribunal, seeemployment tribunals.the (lack of) air up there watch m cay man islands-based webb, the head of fifas anti-racism taskforce, is in london for the football associations 150th anniversary celebrations and will attend citys premier league match at chelsea on sunday.i am going to be at the match tomorrow and i have asked to meet ya ya toure, he told bbc sport.for me its about how he felt and i would like to speak to him first to find out what his experience was.uefa hasopened disciplinary proceedings against cskafor the racist behaviour of their fans duringcitys 2-1 win.michel platini, president of european footballs governing body, has also ordered an immediate investigation into the referees actions.cska said they were surprised and disappointed by toures complaint. in a statement the russian side added: we found no racist insults from fans of cska.age has reached the end of the beginning of a word. may be guilty in his seems to passing a lot of different life became the appearance of the same day; may be back in the past, to oneself the paranoid weird belief disillusionment, these days, my mind has been very messy, in my mind constantly. always feel oneself should go to do something, or write something. twenty years of life trajectory deeply shallow, suddenly feel something, do it.一字开头的年龄已经到了尾声。或许是愧疚于自己似乎把转瞬即逝的很多个不同的日子过成了同一天的样子；或许是追溯过去，对自己那些近乎偏执的怪异信念的醒悟，这些天以来，思绪一直很凌乱，在脑海中不断纠缠。总觉得自己似乎应该去做点什么，或者写点什么。二十年的人生轨迹深深浅浅，突然就感觉到有些事情，非做不可了。the end of our life, and can meet many things really do?而穷尽我们的一生，又能遇到多少事情是真正地非做不可？during my childhood, think lucky money and new clothes are necessary for new year, but as the advance of the age, will be more and more found that those things are optional; junior high school, thought to have a crush on just means that the real growth, but over the past three years later, his writing of alumni in peace, suddenly found that isnt really grow up, it seems is not so important; then in high school, think dont want to give vent to out your inner voice can be in the high school children of the feelings in a period, but was eventually infarction when graduation party in the throat, later again stood on the pitch he has sweat profusely, looked at his thrown a basketball hoops, suddenly found himself has already cant remember his appearance.童年时，觉得压岁钱和新衣服是过年必备，但是随着年龄的推进，会越来越发现，那些东西根本就可有可无；初中时，以为要有一场暗恋才意味着真正的成长，但三年过去后，自己心平气和的写同学录的时候，突然就发现是不是真正的成长了，好像并没有那么重要了；然后到了高中，觉得非要吐露出自己的心声才能为高中生涯里的懵懂情愫划上一个句点，但毕业晚会的时候最终还是被梗塞在了咽喉，后来再次站在他曾经挥汗如雨的球场，看着他投过篮球的球框时，突然间发现自己已经想不起他的容颜。originally, this world, can produce a chemical reaction to an event, in addition to resolutely, have to do, and time.原来，这个世界上，对某个事件能产生化学反应的，除了非做不可的坚决，还有，时间。a persons time, your ideas are always special to clear. want, want, line is clear, as if nothing could shake his. also once seemed to be determined to do something, but more often is he backed out at last. dislike his cowardice, finally found that there are a lot of love, there are a lot of miss, like shadow really have been doomed. those who do, just green years oneself give oneself an arm injection, or is a self-righteous spiritual.一个人的时候，自己的想法总是特别地清晰。想要的，不想要的，界限明确，好像没有什么可以撼动自己。也曾经好像已经下定了决心去做某件事，但更多的时候是最后又打起了退堂鼓。嫌恶过自己的怯懦，最终却发现有很多缘分，有很多错过，好像冥冥之中真的已经注定。那些曾经所谓的非做不可，只是青葱年华里自己给自己注射的一支强心剂，或者说，是自以为是的精神寄托罢了。at the moment, the sky is dark, the air is fresh factor after just rained. suddenly thought of blue plaid shirt; those were broken into various shapes of stationery; from the corner at the beginning of deep friendship; have declared the end of the encounter that havent start planning. those years, those days of do, finally, like youth, will end in our life.此刻，天空是阴暗的，空气里有着刚下过雨之后的清新因子。突然想到那件蓝格子衬衫；那些被折成各种各样形状的信纸；那段从街角深巷伊始的友谊；还有那场还没有开始就宣告了终结的邂逅计划那些年那些天的非做不可，终于和青春一样，都将在我们的人生中谢幕。baumgartner the disappointing news: mission aborted. r plays an important role in this mission. starting at the ground, conditions have to be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. the balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our day-to-day weather lives. it will climb higher than the tip of mount everest (5.5 miles/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into the stratosphere. as he crosses the boundary layer (called the tropopause),e can expect a lot of turbulence. we often close ourselves off when traumatic events happen in our lives; instead of letting the world soften us, we let it drive us deeper into ourselves. we try to deflect the hurt and pain by pretending it doesnt exist, but although we can try this all we want, in the end, we cant hide from ourselves. we need to learn to open our hearts to the potentials of life and let the world soften us.生活发生不幸时，我们常常会关上心门；世界不仅没能慰藉我们，反倒使我们更加消沉。我们假装一切仿佛都不曾发生，以此试图忘却伤痛，可就算隐藏得再好，最终也还是骗不了自己。既然如此，何不尝试打开心门，拥抱生活中的各种可能，让世界感化我们呢？whenever we start to let our fears and seriousness get the best of us, we should take a step back and re-evaluate our behavior. the items listed below are six ways you can open your heart more fully and completely.当恐惧与焦虑来袭时，我们应该退后一步，重新反思自己的言行。下面六个方法有助于你更完满透彻地敞开心扉。whenever a painful situation arises in your life, try to embrace it instead of running away or trying to mask the hurt. when the sadness strikes, take a deep breath and lean into it. when we run away from sadness thats unfolding in our lives, it gets stronger and more real. we take an emotion thats fleeting and make it a solid event, instead of something that passes through us.当生活中出现痛苦的事情时，别再逃跑或隐藏痛苦，试着拥抱它吧；当悲伤来袭时，试着深呼吸，然后直面它。如果我们一味逃避生活中的悲伤，悲伤只会变得更强烈更真实悲伤原本只是稍纵即逝的情绪，我们却固执地耿耿于怀by utilizing our breath we soften our experiences. if we dam them up, our lives will stagnate, but when we keep them flowing, we allow more newness and greater experiences to blossom.深呼吸能减缓我们的感受。屏住呼吸，生活停滞；呼出呼吸，更多新奇与经历又将拉开序幕。2. embrace the uncomfortable we all know what that twinge of anxiety feels like. we know how fear feels in our bodies: the tension in our necks, the tightness in our stomachs, etc. we can practice leaning into these feelings of discomfort and let them show us where we need to go.我们都经历过焦灼的煎熬感，也都感受过恐惧造成的生理反应：脖子僵硬、胃酸翻腾。其实，我们有能力面对这些痛苦的感受，从中领悟到出路。the initial impulse is to run away to try and suppress these feelings by not acknowledging them. when we do this, we close ourselves off to the parts of our lives that we need to experience most. the next time you have this feeling of being truly uncomfortable, do yourself a favor and lean into the feeling. act in spite of the fear.我们的第一反应总是逃避以为否认不安情绪的存在就能万事大吉，可这也恰好妨碍了我们经历最需要的生活体验。下次感到不安时，不管有多害怕，也请试着勇敢面对吧。3. ask your heart what it wants倾听内心were often confused at the next step to take, making pros and cons lists until our eyes bleed and our brains are sore. instead of always taking this approach, what if we engaged a new part of ourselves that isnt usually involved in the decision making process?我们常对未来犹疑不定，反复考虑利弊直到身心俱疲。与其一味顾虑重重，不如从局外人的角度看待决策之事。from: /eng