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1、外文资料翻译Elevator System Based on PLCComposed by the order of relay control system is a realization of the first elevator control method. However, to enter the nineties, with the development of science and technology and the widespread application of computer technology, the safety of elevators, reliab
2、ility of the increasingly high demand on the relay control weaknesses are becoming evident. Elevator control system relays the failure rate high, greatly reduces the reliability and safety of elevators, and escalators stopped often to take with the staff about the inconvenience and fear. And the eve
3、nt rather than taking the lift or squat at the end of the lift will not only cause damage to mechanical components, but also personal accident may occur. Programmable Logic Controller (PLC) is the first order logic control in accordance with the needs of developed specifically for industrial environ
4、ment applications to operate the electronic digital computing device. Given its advantages, at present, the relay control the lift has been gradually replaced by PLC control. At the same time, AC variable frequency motor speed control technology, the way the lift drag speed has been a gradual transi
5、tion from DC to AC frequency converter. Thus, PLC control technology increases VVVF Elevator modern technology has become a hot industry.1. PLC elevator control advantages (1) used in elevator control PLC, with software for automatic control of lift operation, reliability greatly increased. (2) laye
6、r was removed and a majority of the relay, the control system structure is simple, to simplify the external circuit. (3) PLC can be a variety of complex control system, easy to add or change control functions. (4) PLC can be automated fault detection and alarm display to improve the operation of sec
7、urity and ease of maintenance. (5) for the group control the allocation and management, and improve the efficiency of elevator operation. (6) do not need to change the control scheme changes when the hardware connection. 2. VVVF elevator control characteristics With the power electronics, microelect
8、ronics and computer technology to control the rapid development of technology, communication technology VVVF also a very rapid rate. AC variable frequency motor speed control technology is the power to improve the process in order to improve product quality and improving the environment and promotin
9、g technological progress as a primary means. Frequency of its excellent performance and the speed brake from a smooth performance, high efficiency, high power factor and power-saving effect of a broad scope of application and many other advantages of being at home and abroad recognized as the most p
10、romising approach speed Exchange characteristics of VVVF Elevator (1) low energy consumption (2) low load circuit, the required emergency power supply device of small In the acceleration stage, the required start-up current of less than 2.5 times the rated current. Peak starting current and time is
11、short. Since the starting current is drastically reduced, so power consumption and power supply cable diameter can be reduced a lot. Required for emergency power supply devices are also relatively small size. (3) high reliability and long service life. (4) good comfort Elevator operation is best to
12、follow the speed curve of a given operation. Their characteristics can be adapted to human feelings, and to ensure that noise operation, smooth brake Ping layer and high precision (5) Stable noise-free (6) In the car, the engine room and adjacent areas to ensure that noise. Because their systems use
13、 a high clock frequency. Always produce a true sine wave power supply current yet. Motor torque ripple does not appear. Therefore, to eliminate vibration and noise.3. Elevator control technology The so-called elevator control technology refers to the elevator drive system and electrical control syst
14、em of automatic control. 70 as the 20th century in Chinas elevator was marked by the exchange of two-speed elevator. Its speed is used to change the elevator traction motor of the very few, two or multilevel approach to the number of windings, very few of them as high-speed winding of the winding, a
15、 very few number of windings as the low-speed winding. Windings for high-speed elevator-speed start-up and running, low-speed windings for braking and the maintenance of elevators. The early 80s, VVVF inverter controlled variable lift system available. It uses AC motor drives, are able to reach the
16、level of DC motor, control the speed of the current has reached 6 m / sec. Its small size, light weight, high efficiency, energy saving, including the past almost all the advantages of the lift. Is the latest elevator drive system. Operation in vertical lift, there is also the starting point of the
17、terminus station. For more than three-story elevator buildings, the starting point of the terminal stations and stops between the had not, the starting point for these stations at the first floor of the terminal located at the highest floor. Starting point in the first floor of the station known as
18、base stations, known as the starting point at both ends of the terminal stations and stations at both ends of intermediate stops between stations. Outside the station has a call box, box set are used by staff for elevator call button or touch the call button, the general ends of the lift stations in
19、 the call box on the Settings button or touch of a button. Middle layer of the station set up the call box button or touch button 2. No drivers for the control of elevators, at various stations are set up calls me on a button or touch button. Elevator car and the internal settings (except for debris
20、 elevator) to manipulate me. Control box switch on the handle or set up stations and the corresponding layer of buttons or touch-button control box on the touch-control button or command button or touch the city button. Outside the command button or touch-button issue as the signal outside the comma
21、nd signal, within the command button or touch-button issue within the signal as a command signal. 80 In the mid-20th century, the touch button has been replaced by micro-button. As the elevator call box outside the base station, in addition to set up a call button or touch button, but also set a key
22、 switch in order to work the elevator clearance. Drivers or management staff to open the elevator to the base station can wriggle through a dedicated key to the key switch. Close the elevator in place to automatically cut off the elevator control power supply or power supply.4. PLC Control Elevator
23、Design With the continuous development of urban construction, the increasing high-rise buildings, elevators and life in the national economy has a broad application. Elevator high-rise buildings as a means of transport in the vertical run of daily life has been inextricably linked with people. In fa
24、ct the lift is based on external call control signals, as well as the laws of their own, such as running, and the call is random, the lift is actually a man-machine interactive control system, simple to use control or logic control order can not meet the control requirements, and therefore , elevato
25、r control system uses a random control logic. Elevator control is currently generally used in two ways, first, the use of computer as a signal control unit, the completion of the lift signal acquisition, operation and function of the set, to achieve the lift and set the automatic scheduling function
26、 to run the election, drag the control from inverter to complete; the second control mode with programmable logic controller (PLC) to replace the computer control signal sets the election. From the control and performance, these two types of methods and there is no significant difference. Most of th
27、e domestic manufacturers to choose the second approach, because the smaller scale of production, their design and manufacture of high cost of computer control devices; and PLC high reliability, convenient and flexible program design, anti-interference ability, stable and reliable operation of the ch
28、aracteristics of Therefore, the elevator control system is now widely used to realize programmable controller.5. Elevator control system characteristics Operation of the lift curve is above the start to run comfort indicators lift the key features, and comfort are directly related with the accelerat
29、ion, according to control theory, for a certain amount of change according to the law must be directly controlled, for elevator control system, according to the ideal acceleration curve acceleration feedback to be used, in accordance with the motor torque equation: M-MZ = M = J (dn / dt), can be see
30、n reflected in the rate of change of acceleration of the system of dynamic torque changes on the control system to control the acceleration of the dynamic torque M = M-MZ. Therefore, during this time to control the use of the principle of acceleration, when the start rate of increase in steady-state
31、 value above 90%, the acceleration control system by the switch to speed control, as in paragraph steady speed, speed control for the constant fluctuations in the smaller, little change in acceleration, speed and the use of closed-loop control can maintain a steady-state speed accuracy and precision
32、 for the braking section to create the conditions ping layer. Is rising at a rate in the system, and although the above-speed PI regulator used to control, but two of the PI parameters are different in order to improve the system dynamic response indicators. The brake in the system, that is, to redu
33、ce the speed of control necessary to ensure the comfort, but also strictly in accordance with the operation of the lift of the relationship between speed and distance control to ensure the accuracy of flat layers. To the speed in the system before 120r/min, in order to take into account both be take
34、n to control the acceleration of time-based and at the same time in each braking distance based on actual speed and speed deviations from the theory to fix the acceleration curve of a given method. For example, from a flat layer at the distance L, the speed should be reduced to Vm / s, while the act
35、ual high speed Vm / s, is illustrated by the increase in the braking torque is not enough here, therefore to calculate value determined by the speed-ag after it combined with a negative deviation of , even here the value given by the speed of amended - (ag + ) so that a given rate of deceleration an
36、d the actual increase of negative bias, which increases braking torque big, so fast down to the standard value, when the motor speed 120r/min down after the car at this time only a dozen or so cm layer anomaly, low speed lift, in order to prevent yet floor parking area on the phenomenon in order to
37、enable faster access to the lift to floor area ratio adjustment used in this paragraph and the use of optimal control of time in order to ensure accurate and timely access to elevator floor area, in order to achieve accurate and reliable level layer.PLC控制下的电梯系统 由继电器组成的顺序控制系统是最早的一种实现电梯控制的方法。但是，进入九十年代
38、，随着科学技术的发展和计算机技术的广泛应用，人们对电梯的安全性、可靠性的要求越来越高，继电器控制的弱点就越来越明显。 电梯继电器控制系统故障率高，大大降低了电梯的可靠性和安全性，经常造成停梯，给乘用人员带来不便和惊忧。且电梯一旦发生冲顶或蹲底，不但会造成电梯机械部件损坏，还可能出现人身事故。可编程序控制器(PLC)最早是根据顺序逻辑控制的需要而发展起来的，是专门为工业环境应用而设计的数字运算操作的电子装置。鉴于其种种优点，目前，电梯的继电器控制方式己逐渐被PLC控制所代替。同时，由于电机交流变频调速技术的发展，电梯的拖动方式己由原来直流调速逐渐过渡到了交流变频调速。因此，PLC控制技术加变频调
39、速技术己成为现代电梯行业的一个热点。1. PLC控制电梯的优点(1) 在电梯控制中采用了PLC，用软件实现对电梯运行的自动控制，可靠性大大提高。 (2) 去掉了选层器及大部分继电器，控制系统结构简单，外部线路简化。 (3) PLC可实现各种复杂的控制系统，方便地增加或改变控制功能。 (4) PLC可进行故障自动检测与报警显示，提高运行安全性，并便于检修。 (5) 用于群控调配和管理，并提高电梯运行效率。(6) 更改控制方案时不需改动硬件接线。2. 电梯变频调速控制的特点随着电力电子技术、微电子技术和计算机控制技术的飞速发展，交流变频调速技术的发展也十分迅速。电动机交流变频调速技术是当今节电、改
40、善工艺流程以提高产品质量和改善环境、推动技术进步的一种主要手段。变频调速以其优异的调速性能和起制动平稳性能、高效率、高功率因数和节电效果，广泛的适用范围及其它许多优点而被国内外公认为最有发展前途的调速方式。交流变频调速电梯的特点(1) 能源消耗低(2) 电路负载低，所需紧急供电装置小在加速阶段，所需起动电流小于2.5倍的额定电流。且起动电流峰值时间短。由于起动电流大幅度减小，故功耗和供电缆线直径可减小很多。所需的紧急供电装置的尺寸也比较小。(3) 可靠性高，使用寿命长。(4) 舒适感好电梯运行是跟随最佳给定的速度曲线运行的。其特性可适应人体感受，并保证运行噪声小，制动平稳。(5) 平层精度高(
41、6) 运行平稳无噪声在轿厢内，机房内及邻近区域确保噪声小。因为其系统中采用了高时钟频率。始终产生一个不失真的正弦波供电电流。电动机不会出现转距脉动。因此，消除了振动和噪声。3. 电梯控制技术所谓电梯控制技术是指电梯的传动系统及操纵系统的电气自动控制。作为我国20世纪70年代电梯的主要标志是交流双速电梯。其调速方法是采用改变电梯牵引电动机的极对数，两种或两种不同级对数的绕组，其中极数少的绕组称为高速绕组，极数多的绕组称为低速绕组。高速绕组用于电梯的起动及稳速运行，低速绕组用于制动及电梯的维修。80年代初，VVVF变频变压系统控制的电梯问世。它采用交流电动机驱动，却可以达到直流电动机的水平，目前控
42、制速度已达6米/秒。它的体积小，重量轻，效率高，节省能源等几乎包括了以往电梯的所有优点。是目前最新的电梯拖动系统。电梯在垂直运行过程中，有起点站也有终点站。对于三层楼以上的建筑物的电梯，起点站和终点站之间还没有停靠站，起点站设在一楼，终点站设在最高楼。设在一楼的起点站称为基站，起点站和终点站称为两端站，两端站之间称为中间站。各站厅外设有召唤箱，箱上设置有供乘用人员召唤电梯用的召唤按钮或触钮，一般电梯在两端站的召唤箱上各设置一只按钮或触钮。中间层站的召唤箱各设置两只按钮或触钮。对于无司机控制的电梯，在各层站的召唤箱上均设置一只按钮或触钮。而电梯的轿厢内部设置有（杂物电梯除外）操纵箱。操纵箱上设置
43、有手柄开关或与层站对应的按钮或触钮，操纵箱上的按钮或触钮城内指令按钮或触钮。外指令按钮或触钮发出的电信号称为外指令信号，内指令按钮或触钮发出的电信号成为内指令信号。20世纪80年代中期后，触钮已被微动按钮所取代。作为电梯基站的厅外召唤箱，除设置一只召唤按钮或触钮外，还设置一只钥匙开关，以便下班关电梯时。司机或管理人员把电梯开到基站后，可以通过专用钥匙扭动该钥匙开关。把电梯的厅门关闭妥当后，自动切断电梯控制电源或动力电源。4. PLC控制电梯的设计随着城市建设的不断发展，高层建筑不断增多，电梯在国民经济和生活中有着广泛的应用。电梯作为高层建筑中垂直运行的交通工具已与人们的日常生活密不可分。实际上
44、电梯是根据外部呼叫信号以及自身控制规律等运行的，而呼叫是随机的，电梯实际上是一个人机交互式的控制系统，单纯用顺序控制或逻辑控制是不能满足控制要求的，因此，电梯控制系统采用随机逻辑方式控制。目前电梯的控制普遍采用了两种方式，一是采用微机作为信号控制单元，完成电梯信号的采集、运行状态和功能的设定，实现电梯的自动调度和集选运行功能，拖动控制则由变频器来完成；第二种控制方式用可编程控制器（PLC）取代微机实现信号集选控制。从控制方式和性能上来说，这两种方法并没有太大的区别。国内厂家大多选择第二种方式，其原因在于生产规模较小，自己设计和制造微机控制装置成本较高；而PLC可靠性高，程序设计方便灵活，抗干扰
45、能力强、运行稳定可靠等特点，所以现在的电梯控制系统广泛采用可编程控制器来实现。5. 电梯控制系统特性在电梯运行曲线中的启动段是关系到电梯运行舒适感指标的主要环节，而舒适感又与加速度直接相关，根据控制理论，要使某个量按预定规律变化必须对其进行直接控制，对于电梯控制系统来说，要使加速度按理想曲线变化就必须采用加速度反馈，根据电动机的力矩方程式:MMZ=M=J（dn/dt），可见加速度的变化率反映了系统动态转距的变化，控制加速度就控制系统的动态转距M=MMZ。故在此段采用加速度的时间控制原则，当启动上升段速度达到稳态值的90%时，将系统由加速度控制切换到速度控制，因为在稳速段，速度为恒值控制波动较小
46、，加速度变化不大，且采用速度闭环控制可以使稳态速度保持一定的精度，为制动段的精确平层创造条件。在系统的速度上升段和稳速段虽都采用PI调节器控制，但两段的PI参数是不同的，以提高系统的动态响应指标。在系统的制动段，即要对减速度进行必要的控制，以保证舒适感，又要严格地按电梯运行的速度和距离的关系来控制，以保证平层的精度。在系统的转速降至120r/min之前，为了使两者得到兼顾，采取以加速度对时间控制为主，同时根据在每一制动距离上实际转速与理论转速的偏差来修正加速度给定曲线的方法。例如在距离平层点的某一距离L处，速度应降为Vm/s，而实际转速高为Vm/s，则说明所加的制动转距不够，因此计算出此处的给
47、定减速度值-ag后，使其再加上一个负偏差，即使此处的减速度给定值修正为-（ag+）使给定减速度与实际速度负偏差加大，从而加大了制动转距，使速度很快降到标准值，当电动机的转速降到120r/min以后，此时轿厢距平层只有十几厘米，电梯的运行速度很低，为防止未到平层区就停车的现象出现，以使电梯能较快地进入平层区，在此段采用比例调节，并采用时间优化控制，以保证电梯准确及时地进入平层区，以达到准确可靠平层。生命列车The Train Of Life 1. 不久以前，我读了一本书。书中把人生比作一次旅行。2. 人生一世，就好比是一次搭车旅行，要经历无数次上车、下车; 时常有事故发生; 有时是意外惊喜，有时
48、却是刻骨铭心的悲伤 3. 降生人世，我们就坐上了生命列车。我们以为我们最先见到的那两个人-我们的父母，会在人生旅途中一直陪伴着我们。 4. 很遗憾，事实并非如此。他们会在某个车站下车，留下我们，孤独无助。他们的爱、他们的情、他们不可替代的陪伴，再也无从寻找。 5. 尽管如此，还会有其他人上车。他们当中的一些人将对我们有着特殊的意义。 6. 他们之中有我们的兄弟姐妹, 有我们的亲朋好友。我们还将会体验千古不朽的爱情故事。7. 坐同一班车的人当中，有的轻松旅行。8. 有的却带着深深的悲哀 还有的,在列车上四处奔忙，随时准备帮助有需要的人 9. 很多人下车后，其他旅客对他们的回忆历久弥新 但是，也有
49、一些人，当他们离开座位时，却没有人察觉。10. 有时候，对你来说情深义重的旅伴却坐到了另一节车厢。你只得远离他，继续你的旅程。11. 当然，在旅途中，你也可以摇摇晃晃地穿过自己的车厢，去别的车厢找他 12. 可惜，你再也无法坐在他身旁，因为这个位置已经让别人给占了 .13. 没关系。旅途充满挑战、梦想、希望、离别 就是不能回头。因此，尽量使旅途愉快吧！14. 善待旅途上遇见的所有旅客，找出人们身上的闪光点。15. 永远记住，在某一段旅程中，有人会犹豫彷徨，因为我们自己也会犹豫彷徨。16. 我们要理解他人，因为我们需要他人的理解。17. 生命之谜就是：我们在什么地方下车？坐在身旁的伴侣在什么地方