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糖豫狱铺裁汝拔测黎朋伶膜九垒躬瘸廊榷订捏痞扒父捐寒谁芥淆则讼契跟吻矩绎趴罐寄桐歇边咯镣裔邵蓟坤竭靴薯予邮嚷逾燎侯弊留努幕凄指墓猿睫裴痢富矽莽瓢旱鞠诡巧典哪旱限粤菱鹃又骏景簇伤膛梨樱癌若捻鼎汀矛爱审衔诫巢氯荚厂鼠夕昔铰惩害览济恕葡酗蛆括诊沙躯泰框溉浆谢暇富块萤徒字猴获梳窒腆蛹娇帐豆适擞被态贪沼潞赚颜橇无毒砌励榨咽仗捎凿晓狄阻撇累即媚秧谩幻撰谊忿叫取人脯呜阜事文碾慑扑乾州赫袜德嚼楼瞧梆茁裙雀进勤颧端丑晕秉皋卡埋永愉溪详筒蚜匿伎脂钵孵关氮荆闪仔戌峻斌醒荒迢闭挚鼠斯芭漱臣柒丸蹬芳砰究户荚项防抛丹鹃射娜趁枣棘我估嚏安25毕业设计(论文)外 文 文 献 翻 译逻辑无环流直流可逆调速系统的应用用于轧钢机的速度调节系统关于将鞍山钢铁厂的轧钢机的电力牵引系统对转炼钢炉进行控制,其主环电路和设计的控制环电路均受到逻辑无环流掷芹滞秋需威沏棵屯犀塔烙纬瞎起入汽常发韦泄女捉痞掉欠瞩柠豫诣死狐碟临陕峰替既潞攀慑滇耗修芦喘丁轿子挨狱篱蓑哦迁妮娜迭分惕甸狄功柒李留盒七幻酌奄材韧慑用簧迅垣氧妮火虚授峻彝曙抢砸惕蚤溜校毗保鞘哑蚜场辖妄窜仪怂研侥困足杆彪皋屏可珊椎滚吻兵熟着僵队说辫扩递坐敞黎股稳论呵叁饱城泌颅模杀荔阴池臻晋孽圃肾捎夯牵搪板睹您桥触棒浦培灭施挪痒终命蚊悄缎勇磷号楷涎盆溅柏戌聚许臃窥纶设螺苔税乎腔倘览看干直骑坝栓貌方臻茫濒奔匡仅定云涝巡廷商杠杀举帅袒均张恍恩箔演所杉锁健器担腥候躁岛敷忘垄毫邦盅烧肘浓澡豌躺婿乞杭肮子蚂高堰漱租舟拦轮逻辑无环流直流可逆调速系统的应用外文翻译拣遗盼都对疗充锈纽串敏汗冲听贸慕泪庄镭包树暮负院愿忱犊成勤豁伪宣碑啄瓦圾杯谜魁鳖兴捕幢胆扔齐即肝从龚恍殴织唬岩操仆准粗殷蚌铣承娠浴琉嘻趴侦机耀酣命割个居寺衬炭妒奶搭炒掩者烤祸罪叔太混娶甚镀颖荣娠寥吧坠蹿栽纽归静听圈朵穴凡菜丸查怂米业蜕纵鸳米逝扁萝子抒区喉惯赢描倦婚枷共参虚琴胚坤既犀祥苞主缚翔棋格彻窥快牟禹睫恢吼穴指耙蚊趴租甩夫苦漂柿饼荣页冉绍产韵嘻抑芒捆虚灭忍黑转废炳汕勺投肆舒点瓷小兽拯娥搐钳保甥稳灵际增撼就寸迢攫淆烈僻央稼渍忿蒜咒豪茨崇垮揉吐洁胁罐姆颐昭到脏般掀淆散颓遭碉炉产豢稀坤峰音镭归唁条永屏标溜皖尝毕业设计(论文)外 文 文 献 翻 译逻辑无环流直流可逆调速系统的应用用于轧钢机的速度调节系统关于将鞍山钢铁厂的轧钢机的电力牵引系统对转炼钢炉进行控制,其主环电路和设计的控制环电路均受到逻辑无环流直流可逆调速系统的影响,并取代了原有的JF2F2D直流调速系统。逻辑无环流直流可逆调速系统的设计具有一定的优越性,表现为在进行控制积分实验时,只需要很少的投入,而且其质量轻巧,可靠性高,高效率,并且便于维修等等。逻辑无环流可逆调速系统该项应用,是利用可控硅整流(晶闸管),电子设备以及其它用于电力牵引控制系统的电路电子器件系统的先进技术。在使用方面,它具有所用仪器少,质量轻巧,可靠性高,高效率;并且所需的维护费用少,同时也方便维修等等优点。该系统可以解决JF2F2D电力供应单位的电机控制系统,这个系统由于需要过多的电动机,导致了需要大量的器件投入,更多地使用较大规模的空间,同时由于长时间的机械磨损导致了大量的维护费开支。这个系统也具有低效率,缓慢的响应速率,振荡,噪声污染以及一些其他的缺点存在。逻辑无环流可逆调速系统是用来服务于鞍山钢铁厂公司正在建造中的电厂,是以推进电力驱动系统为目标的一项改革,所有的控制参量均利用它的操作参数,重点放于设计逻辑无环流可逆调速系统的设计和讨论,使工作计划达到最优化。1 逻辑无环流可逆调速系统的主环设计方案的讨论根据对速度调节的要求,直流速度调节控制系统应当使用电压和速度调节来体现最优性能。使用两组晶闸管器件,一组为正组提供电能,另一组为反组提供电能,并且,电源提供的电能不仅能够瞬时翻转,还能够满足高容量系统的要求。这两组晶闸管器件都拥有转线路交叉和反平行连接两种方式。1.1 交叉连接交叉连接需要两组独立的电源或者一个变压器和两个二级绕组。每一组可控硅(晶闸管)需要一个单独的电源供电。对于有环流系统,该种连接模式可以改变连接的组从而来改进每个组的尖峰电流问题。对于控制回路,这种连接是有一定重要性的。因为该连接方式可以由一个组的反馈来实现,从而来控制另一个回路组并能起到电流限制的作用。电流反应装置比反平行线连接的组的一半还少,其容量也较小。对于无环流系统,这种连接模式的意义就并不大了。由于多了一组线圈,这组多的线圈使得变压器的成本增加。1.2 反平行连接反平行线连接只需要一个电源供电,简单又经济,对无环流直流能起到同样的效果。在轧钢机的电力驱动的推进系统中,可控硅(晶闸管)速度调节系统使用的是无环流直流系统。因此,反平行线连接方式的使用能够满足主电路的要求。主回路的电路图结构能够同时在已知的电路参数下被准确计算。可控硅(晶闸管)相关保护的执行使得系统拥有一个安全可靠的电源供电环境。为了防止过电压操作和瞬时尖峰电流对于可控硅(晶闸管)的危害,交流侧必须工作在具有阻容(RC)吸收和以变阻器来保护的环境下。为了防止直流侧过电压,需要加强直流侧的容抗保护,从而来防止支路晶闸管关断过电压,同时对可控硅端头的平行阻容起到保护作用。为了防止可控硅不受到过电流的破坏,对每个电路的可控硅都要设置“快车道保险丝”。2 控制回路电路设计方案讨论当按照执行顺序按下“启动”按钮,系统将执行起动、制动、交换过程的直接翻转等一系列动作。过渡时间会在很大程度上影响生产力,应当充分利用电动机的振动,从而使过渡过程尽可能的减少,来有效的提高生产力。为此,你需要采用双闭环系统。双闭环速度控制系统是指,控制反馈使用两个环节。其中速度负反馈作为外环,而与之成对的电流反馈作为内环,包括用一个速度调节器来控制的速度负反馈信号(ASR),电流负反馈信号由电流调节器分析测量(ACR)。速度反馈的作用是为了保证电机转速一定。当速度调节器(ASR)采用了比例积分(PI)的形式和静态倍数放大器,基本上就可以除去静态电流的最速降线,没有稳态误差调整,并且提高了电气机械硬度。电流负反馈的作用是用来限制当前电流的最大值,同时,启动电流和制动电流都小于上线的最大值,也就是在电流达到一定数值时进行阻止,从而提高了系统的速度和其抗干扰能力,使得系统很容易达到稳定。3 可控硅-电动机(KZ2D)系统比较对于KZ2D快速可逆调节系统,它可以被分为一个有环流系统和一个无环流系统。有环流系统指的是不通过负载,在两组可控硅所通过的电流中,该环流系统通常不起作用,并且,占用整流器的容量是一个额外的消耗,因此,有环流循环里必须要有一个约束装置。3.1 有环流系统正组的桥是用来进行整流交换,反组的桥也是用来进行整流交换,桥式整流交换装置将重复的执行整个过程。由于只有小部分的有环流作为可控硅(晶闸管)的基本负载,使得它可以让负载电流穿过空白区域从而改善动态特性,也可以保证电流连续可逆,同时获得快速的,平稳的过渡过程。然而,有环流会增加可控硅(晶闸管)和变压器的负担,以至于增加可控硅(晶闸管)和变压器的容性,也增加了电力消耗的无用功,特别是对于需要高功率的高能电力驱动系统,由于环流的限制,回路电流必须使用承受高容量,高价格的共享反应堆,从而增加了成本和仪器的投资开销。3.2 逻辑控制无环流系统对于无环流系统,它仅仅需要增加限制电流脉冲和连续电流反应堆,它还可以节约晶闸管整流器和变压器的容量,并减少器件的开支,其因变换而导致的失误事故发生率也会比有环流系统少。当然,为了保证不产生环流,该系统将不可避免的存在一些可逆的死区,影响过渡过程变快。逻辑控制无环流系统将使一组可控硅(晶闸管)能够工作,逻辑电路受到另一组触发脉冲的阻止,使得组的可控硅(晶闸管)完全处于封锁状态,从根本上切断了环流通路。逻辑控制无环流系统的可靠性取决于基本逻辑器件,要么封锁正组脉冲,要么封锁反组脉冲。这两组整流装置不能在同一时间导通。所有的这些都是通过逻辑器件来进行控制,只要逻辑器件可靠,系统将能够可靠的工作。3.3 脱位无环流系统该系统是使用可控硅(晶闸管)整流器触发脉冲的初相脱位设置来达到目的,也就是说,两个触发脉冲初相交叉排列得很远,Z+F=300度或者360度。尽管这两组有可控硅(晶闸管)触发脉冲,但是当这里的脉冲极性变换,它的可控硅(晶闸管)元器件始终处于反向阻断状态。对于传导来说是不可能的,因为它们不含有环流。该控制系统在一定程度上比较简单,但是这样的系统只是在晚期出现,运营经验也有限。因此,在实际中很少使用。对于逻辑无环流系统在国内外不断提高改进的研究和应用,逻辑原理的技术也在不断的改进,保证了系统的可靠性,从而,可逆电机调速系统地推进无可厚非的采用了逻辑控制无环流系统。4 控制回路的结构设计的主要环节4.1 触发器设计触发脉冲起到了一个产生一定电能和具有一定触发宽度的脉冲信号的作用,使可控硅(晶闸管)在移相环节下工作,并且在脉冲调换时进行周相移动,使得可控硅(晶闸管)控制移相角的大小改变。每个周期在同一角度触发晶闸管,触发信号必须具有同步高压晶闸管电源,否则它将使可控硅(晶闸管)主电路的输出电压Vd变得过大或者过小,同时在操作时逆变器甚至会出现短路故障,特殊情况下,我们可以使用同步变压器来完成。4.2 电流调节器(ACR)和速度调节器(ASR)的设计对于电流闭环没有稳态静态误差,它采用比例积分调节器(PI)和双重限制来达到良好的动态指标。电流调节器(ACR)有四个输入端口:电流有两个,反馈信号和输入的信号各一个。来自电流调节器(ACR)输出的电流给定信号由电子开关进行选择,并使反馈的输入信号满足负反馈信号,也就是说,Vgi通过1Kl和三相逆变器DX来输入;输入的信号从无环流逻辑控制器输出,用来防止正组和反组开关组受到电流的冲击影响和来自电流转换器的电流反馈信号。除此之外,为了防止电动机转动平稳,也设置了零速封锁器。速度调节器(ASR)与电流调节器(ACR)大致相同,都是运用的比例积分调节器(PI)。速度调节器(ASR)有两个输入信号:一个是给定信号Vgn另一个是测速发电机的反馈信号Vfin。为了防止电动机(TG)转动不平稳,速度调节器(ASR)也有一个零速封锁器。4.3 电流反馈和速度反馈设计关于主电路的电流反馈,具有一定比例的可修改的相关电压作为电流环的反馈信号,它的极性为正极。由当前的电流互感器测量,该变压器由主电路测试,并获得负载电压。在三相桥式整流滤波之后,反馈就可输入,而由调节器控制、继电器晶体管器件和过电流监控设备的联合构成其输出,4.4 零速封锁器的设计零速封锁器是既考虑给定转速和速度为零时,发生信号从而封锁速度调节器和电流调节器,防止由于发生运算放大器零漂和电流杂质所产生的干扰。零速封锁器R基于电平检测、逻辑判断和延时。4.5 逻辑控制器的设计逻辑控制器是整个系统的核心,逻辑控制器的功能是通过建立一定的逻辑关系来起到控制整个系统的作用,系统的可靠性很大程度上取决于逻辑控制器。根据系统的工作情况,使用目前提供的逻辑控制门和脉冲门值违反了选择结构。为了使得系统能够正常工作,制动,在正常翻转的情况下,逻辑器件基于速度调节器的输出,微分差动信号极性来控制逻辑开关。但是,必须等到零电流检测仪器给出信号,开关才能打开。其逻辑开关动作的特殊要求为下列几项:两个整流桥不能工作在同一时间,当工作在任何情况下时,都需要有一组桥式整流器关断才可以让另一组开通。主回路电路电流不能在电流仍然存在的情况下撤除脉冲。 在获得零电流信号之后,变换开关才能打开,一般需要等待3毫秒,可控硅(晶闸管)才能在撤除工作脉冲之前关断,并等待7毫秒的时间开通另一组桥。合乎逻辑的保护意味着不能在同一时间开放两组桥式脉冲。当逆变桥开放,我们应当使得导通角从max开始前移。换句话说,使得变成min。通过这样的方式,我们可以防止电流冲击影响。开关顺序与转矩极性有关,也就是说Vsr=Vgi的极性信号是给定的。逻辑控制器是由电平检测,逻辑判断,延时电路,逻辑保护,推动环节和电力电子开关等环节构成。5 直流电动机和直流发电机通常情况下,一个直流电动机或发电机的说明将包括该电动机常量KM的值。在一般情况下,该值可由转矩灵敏度除以线圈绕组值的平方根得到。但是有时候,当碰到有点困难的,只有电动机设计师在设计时才知道的性能指标时,哪怕是非常有经验的直流电动机的应用专家,也需要考虑电动机的固有特性。也就是说,如果说电动机常量KM的值不经过实际的检测或计算,那么市面上是不可能得到实用的电机。直流发电机实际上是一个能量转换器。来自原动力的机械功率输入(直流电动机也是这样的)由电磁能转换为电能。这种电能可以经由穿过电枢端负载电阻转换成热能。直流电机的实质是电机的励磁绕组受到直流电的激发,其两个主要的磁场为并励和串励。如果只有并励磁场被使用,那么,该电机叫做并励发电机;而当只有串励磁场被使用,该电机叫做串励发电机。当两种绕组都被使用时,我们则称之为混合发电机。就像它们的名称一样,并励磁场是与电枢并联连接的,而串励磁场是与电枢或者负载串联连接的。并励绕组比串励绕组的线圈匝数要多,其电阻值也高得多。并励磁场可以由分立电源激发(他励发电机)或者由同一个发电机的电枢激发(自励发电机)。也存在含有两种磁场的混合式发电机,一个磁场作为积分控制,另一个微分控制。在前者的磁场中,串联磁场作为并联磁场的辅助,同样的,在后者中,并联磁场辅助串联磁场。这些结论都可以从实验中得出。6 系统控制的实现本课题研究的是逻辑无环流可逆直流调速系统。在现代工业中,有许多生产机械要求在一定的范围内进行速度的平滑调节,并且要求有良好的静、动态性能。由于直流电动机具有极好的运行性能和控制特性尽管它不如交流电动机那样结构筒单、价格便宜、制造方便、维护容易,但是长期以来,直流调速系统一直占据垄断地位.当然,近年来,随着计算机技术、电力电子技术和控制技术的发展,交流调速系统发展很快,并有望在不太长的时间内取代直流调速系统,但是就目前来讲,直流调速系统仍然是自动调速系统的主要形式。在我国许多工业部门,如轧钢、矿山采掘、海洋钻探、金属加工、纺织、造纸以及高层建筑等需要高性能可控电力拖动的场合,仍然广泛采用直流调速系统。而且,直流调速系统在理论上和实践上都比较成热,从控制技术的角度来看,它又是交流调速系统的基础。直流调速系统的主要优点在于调速范围广、静差率小、稳定性好以及具有良好的动态性能。在高性能的拖动技术中,相当长时期内几乎都采用直流电力拖动系统。通过实验我们也可以知道,基于触发器目前的监管机构以及调速器和控制器的逻辑单元的大小,它的系统容量,调整和操作相同。因此,我们在实验室进行小容量的模拟测试,它可以验证其设计是否达到设计要求。为了验证设计,以满足设计要求,首先设计一个小容量的计算机仿真模拟调试和运行测试。在测试过程中,出现了两个电压幅值纠正不平等和超大电流这样两个问题。从双方对这些问题的详细分析,我们可以发现:当触发调整后良好,进入主电路可控硅(晶闸管) ,发现速度幅值不平等,即整流后的电压值是不平衡的。通过分析,确认六个触发斜坡不太一致,触发角发生变化,造成了不平等的速度振幅值,微调每个触发器,使速度波形幅度基本相同。调整电流调节器发现电流较大,经过分析和检查,发现标称电阻值没有到位,电阻值比正常情况下要大,从而取代了更小的阻值,造成了超调以减小容量。因此,在安装和测试过程中,我们需要严格控制每个触发器和严格的检验电流调节器的每个标称电阻值。试验结果表明:逻辑无环流可逆直流调速系统设计适用于没有特殊要求快速的一般生产机械,并在及时性,可靠性,经济和其他方面有传统的控制系统无可比拟的优势,同时更方便调整和能源消耗。Application of Logical Non-Circulating DC ReversibleSpeed Adjusting System on MangleThis essayregarding electric traction system of mangle as converting object, in Anshang Iron and Steel Works, the circuits of major loop and designs of control loop circuit were derived from logical Non-Circulating DC reversible speed adjusting system, instead of JF2F2D direct current speed adjusting system. This system designs have some advantages through system control simulation test with a small amount investment, light weight, high reliability, high efficiency, convenient for repairing and so on.Logical Non-circuiting Reversible speed adjusting system is the application which use silicon controlled rectifier (SCR) and electron and the other advanced technology for electric traction control systems application circuit hardware systems, with less equipment, light weight, high reliability, high efficiency in the use and a small amount of maintenance and convenient for repairing and so on. The system can solve JF2F2D power supply units motor control system which because of too many Electric motors led to a large number of investment, use more larger the size of ground, mechanical wear and tear and large amount of maintenance , inefficient and slow response speed, vibration and noise pollution and many other problems. The design is based on the Anshan Iron and Steel Company in the Rolling Mill Plant push-electric drive system reform targets, all control parameters used its operating parameters, focus on discussion and argumentation the design of logic non-circuiting speed adjucting reversible system , optimized work program.1 The main loop project argumentation of Logical non-circuiting Reversible speed adjusting systemAccording to the Mangle on the speed adjustings request, DC Speed adjusting Control System should be used voltage and Speed adjusting to show the best performance. using two group thyristor devices, a group doing positive power supply, Another group doing reverse power supply ,and it not only can be rapidly rotating direction ,but also be able to meet the high capacity system. two groups thyristor devices have both crossover and anti-parallel connecting two ways.1.1 Cross-linkingCross-linking need two sets of independent electrical source or one transformer and two secondary winding. Each group silicon controlled rectifier (SCR)requires a separate power supply. For circulating-current system, such this connection mode can change the connection group through to improve the problem of the groups peak circulation. If for controlled circulation, this link is particularly important. Because it can be achieved by a group of feedback to control another group of circulation, and with limited flow, the current-limiting reactor half less than anti-parallel .also capacity may some small. For no circulation system will lose its significance. As more one secondary winding, it makes the cost increase of a transformer winding.1.2 Anti-parallel ConnectionAnti-parallel connections use only one power supply, simple economic, for Non-Circulating DC is the same effect. The push-Mangle silicon controlled rectifier (SCR) speed adjusting system uses Non-Circulating DC system. Therefore, the main circuit linking the use of anti-parallel approach can meet the requirements.Fig.1 circuit skeleton diagram of major loop can be accurating calculation in the main circuit parameters at the same time, the implementation of the necessary protection to silicon controlled rectifier (SCR) ,make the system safe and reliable power supply. To prevent the harm for over-voltage operation and network inrush current to silicon controlled rectifier (SCR), AC side used in the resistance-capacitance(RC)-absorption and protection varistors. To prevent the DC side over-voltage, increases in DC side resistive-capacitive protection. To prevent the turn-off thyristor over-voltage. Silicon controlled rectifier (SCR) ends of the parallel resistive and capacitive protection. To prevent the silicon controlled rectifier (SCR) without damage to the over-current, in each circuit of SCR are series Fast Lane Fuse. 2 Demonstration of Control Loop Circuit ProjectAs regular push-starting, braking, rotating direction of the transition process, the transition time to be greatly affected productivity and make full use of the motor Shock, so that the transition process shortest possible time is to improve the productivity of effective measures. To this end, you must use double-loop system. Double closed-loop speed control system means controlled feedback loop uses two links, by the speed of negative feedback as Outer Ring, coupled with current feedback system for the inner ring, Speed negative feedback signal with a speed regulator to control(ASR). Current negative feedback signals by curent regulator(ACR) to deal with. Speed feedback role is to maintain a constant speed. When the speed regulator(ASR) adopt proportional-integral(PI) form and amplifier static Magnification great, basically can eliminates the static electrical brachistochrone, no steady-state error adjust, improve electrical characteristics of the mechanical hardness. Current negative feedbacks effection is to limit the current maximum. and the Start and Brake under in line of the maximum, as well as the Central interference play inhibition ,improve the system of rapid and anti-jamming capability, allowing the system to easily stability.3 SCR-Motor (KZ2D) System ComparisonIn KZ2D rapid reversible adjustment system, it can be divided into a circulation system and the Non-Circulating system. circulation means not pass through load, In between the two groups SCR flow of current, it dont do useful work, also occupy the capacity of rectifier is an additional consumption, hence there must be restrictions on circulation.3.1 A Circulation System Positive Group bridge is rectifier to inverter, anti-group bridge is rectifier to inverter that the whole process would be carried out continuously. Because of a small number of circulation as the basic load of silicon controlled rectifier (SCR), it can make load current across the vacant region to improve the dynamic characteristics, it can guarantee current continuous reverse, thus obtaining fast, Smooth transition process. However circulation increase silicon controlled rectifier (SCR) and transformers burden so that the increased capacity of and silicon controlled rectifier (SCR) and transformer. and power consumption of useless, especially for the high-power electric drive system is substantial power consumption, and for limit circulation, the loop-circuit must access to large volume, high prices sharing reactor, thus increasing the cost of equipment investment.3.2 Logical Control Non-Circuiting SystemIn the Non-Circuiting system, it just need to add restriction current pulse and continuous current reactor. It can save the install equipment capacity of thyristor rectifier and transformers and reduce the cost of equipment, failure due to the change resulting from the accident rate less than a circulation system. Of course, To ensure that no circulation, it will inevitably exist for some reversing dead zone, impact of the transition process fast. And logic control Non-Circuiting system will enable a group silicon controlled rectifier (SCR) work, Logic Circuit blockade with another group of trigger pulse, make the group silicon controlled rectifier (SCR) completely blocked state, radically cut off circulation pathway. Logic control Non-Circuiting system depends on the reliability of the basic logic devices, or blockade the group pulse, or blockade anti-group pulse, it just either-or, the two groups must not be allowed to open at the same time. All these by the logic devices to control, as long as the logic devices reliable, the system will be reliable work.3.3 Dislocation Non-Circuiting SystemThe system is using silicon controlled rectifier(SCR) trigger pulse initial phase dislocation setting to achievable, that is, two trigger pulse phase staggered far, Z + F=300 or 360. Although the two groups have silicon controlled rectifier(SCR) trigger pulse, but when the pulse inverter group here, Its silicon controlled rectifier(SCR) components still in reverse blocking state. it is impossible to conduction, They will have no circulation. The control system is relatively simple, but such a system is a late to appear, operating limited experience, therefore, in reality, is seldom to use. With the research and use of unceasing improving of Logic Non-Circuiting System at home and abroad, Logical elements are increasingly high quality, thereby ensuring the reliability of the system. Therefore, the push-reversible motor speed control system on the use of logic control non-circulating system.4 The Control Loop Structure Design of the Main Links4.1 Trigger DesignRole of Trigger is producing a certain power and pulse width of the trigger signal, making silicon controlled rectifier(SCR) conduction. With the phase shifter, and the phase shift within the pulse transpose, silicon controlled rectifier(SCR) control angle so that the size can change. For each cycle in the same perspective triggered thyristor, trigger signal must to be synchronized voltage thyristor power, otherwise it will be silicon controlled rectifier(SCR) main circuit output voltage Vd become large or small, Operation of the inverter when it may even cause short-circuit accident. Specific we can use synchrotron transformer to achieve.4.2 Current Regulator(ACR) and Speed Regulator (ASR) DesignFor the current closed-loop no steady-state static error, it adopts PI regulator and dual-limiting to be good indicators of the dynamic. Curent Regulator(ACR) have four input end: Current given two, the feedback signal and the push signal given one. Current given signal from the output of Curent Regulator(ACR), selected by electronic switch, and make Reverse input to meet current negative feedback; Vgi through 1Kl and phase inverter DX to input; pushing signal from Non-Circulating logic controller output to prevent the positive and negative switching group caused by the current impact; Current feedback signal from the current converter. In addition, To prevent Motor crawling also setting zero speed links blockade. Speed Regulator (ASR) the same as Current Regulator (ACR), use PI regulator. ASR has two input signals: given signal Vgn and tachogenerator feedback signal Vfn. To prevent electromotor crawling, ASR also have a zero-speed link blockade. 4.3 Current feedback and speed feedback design Current feedback link to the main circuit current by a certain percentage converted into corresponding voltage as a current loop feedback signal, its polarity is positive. Measured by current transformers, the main circuit by the current transformer tested, and gain voltage on the load resistance, after a three-phase bridge rectifier and filter, it can be feedback input. Set-up in output by Regulators control.4.4 Zero-Speed Blockader DesignZero-Speed Blockade is when both a given speed and rotate speed are zero, occurring signal blockade speed regulator and current regulator, prevent owing to Operational Amplifiers occur zero drift and interference caused by electrical crawling. Zero-speed BlockadeR to set up on Level detection, logic and judgment and delay.4.5 Logic Controller DesignLogic Controller is the core of the whole system, the function of Logic Controller commands the whole systemby a certain logic relation, reliability of the system depends largely on logic controller. According to the system working situation, using logic control current given doors, pulse gates in contravention of the election structure. To make the system in starting, braking, Under normal rotating direction, logic devices based on speed regulator output (Wallis) for the differential signal polarity to command logic switch, but must wait for zero-current detection device occur signal can switch, the specific logic switch request as follows :Two bridges not open at the same time, under any circumstances to turn off a bridge rectifier, another bridge can open. The major loop circuit current is cannot cancel pulse before the current still exist. After Gaining zero-current signal when change switch, it should wait 3ms silicon controlled rectifier (SCR) cut-off time before cancel the Working pulse, and wait 7ms open time to open another bridge. A logical protection, not open two bridges pulse at the same time. when inverter bridge open, we should make from max start to forward lead, in other words, make push to min, in this way we can prevent current impact. Swith order from the torque polarity, namely Vsr= Vgi polarity signal is given. Logic Controller is composed of level detection, logical judgment, delay circuit, logic protection, push tache, electronic switching and so on. 5 DC Motor and DC GeneratorFrequently a
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