卷扬机外文翻译文献

卷扬机外文翻译文献
卷扬机外文翻译文献

卷扬机论文中英文资料外文翻译文献

英文原文

Control of Electric winch

For motor control, we know the best way is to use the style buttons to move the many simple manual console. And this console, in some applications may still be a good choice, as some complex control headache can also be used. This article describes in your design, build or purchase winch controller, you have the motor's basic electrical equipment and you will need to address the user interface command addressed.

First, the manual should be a manual control console type, so if you remove your finger buttons, hoist will stop. In addition, each control station equipped with an emergency need to brake, hoist the emergency brake to cut off all power, not just the control circuit. Think about it, if the hoist at the stop, it did not stop, you do need a way to cut off the fault line protection power. Set the table in the control of a key operated switch, is also a very good idea, especially in the line leading to the workstation can not control, you can use the switch.

(in the design of the console, even the simplest manual console, but also consider setting by specialized personnel to operate the safe operation of the keys.) Constant speed motor control

For a fixed speed winch actual control device is a three-phase starter. Turn the motor is reversed, by a simple switch controlled phase transformation sequence from ABC to CBA. These actions are completed by two three-pole contactor-style, and they are interlocked, so that they can not be simultaneously closed. NEC, required in addition to overload and short circuit protection devices. To protect the motor against overload due to mechanical effects caused by overheating in the heat

to be installed inside the starter overload delay device. When the heat overload delay device overheating, it has a long double off the metal motor power. In addition In addition, you can also select a thermistor can be installed in the motor winding way, it can be used to monitor motor temperature changes. For the short-circuit protection, we generally used by motor fuses to achieve.

A linear current independent contactors, the contactors are configured should be more than the current main circuit contactor, so as to achieve the purpose of redundancy. This sets the current contactor is controlled by the security circuit, such as: emergency brake and the more-way limits.

We can use the limit switches to achieve the above operation. When you reach the end of the normal travel limit position, the hoist will stop, and you can only move the winch in the opposite direction (ie, the direction away from the limit position.) There is also need for a more limited way just in case, due to electrical or mechanical problems, leaving the operation of hoist limit bit more than normal. If you run into more limiter, linear contactor will open, therefore, can not be driven winch will exceed this limit position. If this happens, you need to ask a professional technician to check the lead to meet the more specific reasons limiter. Then, you can use the starter toggle switch inside the elastic recovery process to deal with more problems, rather than tripping device or a hand-off the current contacts.

A necessary condition for speed

Of course, the simple fixed speed starter is replaced by variable speed drives. This makes things start to get interesting again! At a minimum, you need to add a speed control dial operation platform. Joystick is a better user interface, because it makes you move parts of a more intuitive control.

Unfortunately, you can not just from your local console to send commands to control the old variable speed drives, in addition, you can not want it in the initial stages, will be able to enhance the safe and reliable and decentralized facilities. Most of the variable speed drive can not achieve these requirements, because they are not designed to do upgrading work. Drivers need to be set to release the brake before the motor can generate torque, and when parking, that is, before the revocation of torque, the brake will be the first action.

For many years, DC motors and drives provide a number of common solutions, such as when they are in a variety of speeds with good torque characteristics. For most of the hoist of the large demand for DC motor is very expensive, and that the same type of AC motor than the much more expensive. Although the early AC drives are not very useful, as they have a very limited scope of application of the speed, but produced only a small low-speed torque. Now, with the DC drives the development of low cost and a large number of available AC motors has led to a

communication-driven revolution.

Variable speed AC drives in two series. Frequency converter has been widely known and, indeed, easy to use. These drives convert AC into DC, and then, and then convert it back to exchange, the exchange after the conversion is a different frequency. If the drive produced the exchange of 30Hz, 60Hz a normal motor will run at half speed. Theoretically, this is very good, but in practice, this will have a lot of problems. First of all, a typical linear motor 60Hz frequencies below 2Hz 3Hz area or there will be errors, and start cog (that urgent push, yank), or parking. This will limit your speed range lower than 20:1, almost not adapted to the operational phase of the fine adjustment. Second, many low-cost converter is not able to provide the rated torque at low speeds. Use of these drives, will result in the rapid move to upgrade the components or complete failure, precisely, when you try to upgrade a stable scientific instruments, you do not want to see this situation. Some new inverter is a closed-loop system (to get feedback from the motor to provide a more accurate speed control), and the motor will work quite well.

Another series of AC drives is the flow vector type drive. These components require installation of the spindle motor encoder, encoder makes use of these drives can accurately monitor the rotation of the motor armature. Processor accurately measured magnetic flux vector values that are required to make the armature at a given speed rotation. These drives allow infinite speed, so you actually can produce at zero speed to rated torque. These drives provide precise speed and position control, so these drives in high performance applications to be welcomed.

(Based on PLC controllers provide system status and control options. This screen shows the operator full access to the nine-story elevator enhance the control panel.) PLC-based systems

Is the full name of a PLC programmable logic controller. First of all, PLC controller developed to replace the fifties and sixties-based industrial control system

relay, they work in harsh industrial indoor environments. These are modular systems that have a large variety of I / O modules. The modular system can easily achieve the semi-custom hardware configuration assembled, and the resulting configuration is also very reasonable price. These modules include: position control module, the counter, A / D and D / A converter, and a variety of physical state or physical contact with closed output module. Large number of different types of I / O components and PLC module property makes it an effective way to assemble custom and semi custom control system.

The biggest shortcoming of PLC systems is the lack of the real number of display to tell you what is being done and the PLC on the PLC program to help you.

T he first is professional entertainment for the large-scale PLC system is one of the original in Las Vegas, MGM (now Bailey Company) of the riding and carriage system. Many manufacturers offer a standard PLC-based semi-automated acoustic systems and a host of signs, set the location of the command line interpreter, and the upgrading of the control system is also available. Using standard modules to set user-defined system configuration capability is based on the PLC controller of the greatest advantage.

High-end controller

For complex transmission, the controller became complex, more than speed, time and location control. They include complex instructions to write and record the movement contour, and the processing can immediately run the ability to multi-point instructions.

Many large opera house is toward the direction of point lift system, where each one is equipped with a rope to enhance independent winches, rope equivalent to those of each dimmer circuit. When more than one hoist is used to enhance the individual part, the hoist must be fully synchronous, or the load to shift, so will lead to a separate winch becomes the risk of overload. Control system must be able to be selected to keep pace winch, or a hoist winch is not able to maintain synchronization with the other, can provide the same high-speed parking capacity. For a typical speed of 240 ft / min and a winch to maintain the rate of error of between 1 / 8 points of equipment, you only have less than three microseconds of time to identify problems and try to correct the error The hoist speed, make sure you fail, you start all the winch stop the group. This will require a large amount of computation, fast I / O interface, and easy to use to write software.

For large rope control system has two very different solutions. The first is to use a separate console, the problem in general terms, this console should be installed in the appropriate location of the operator perspective. However, this not only from one angle to another angle, but still can not get an instruction to another instruction

from the control. These difficulties have been partially resolved. Installed in different locations through the use of video cameras, and these cameras connected to the three-dimensional display graphics, these graphics enables the operator to observe from the perspective of any of the three coordinates in the expected direction of rope movement. These operators can make from a console for him at the actual angle, or closed circuit camera practical perspective, to observe the movement of the rope on the screen. For the complex interrelated moving parts, makes the implementation of the above observation Failure to control and find out easier.

Another solution to the problem is a distributed system that uses multiple light console. This will allow the different operators in the same way the different aspects of control gear, we have improved the manual control device. A vivid example is the flower in a vegetable market in central London, the Royal Opera House, the program uses the above, where the control console 240 with ten motors. Each console has five playback device, and has been open, so that each motor has been assigned to a single console. An operator and a console can control all the devices, however, often may be running a console platform screen upgrade, another console is a console on the transmission device, and the third console is used to the necessary background in the background image down.

(edge-type portable console allows the operator many advantages from the start to control the movement of the machine, and provide three-dimensional image display.)

Conclusion

A huge change in the rope control system, a workstation has been developed from a push-button to complex multi-user computerized control system. When the control system to buy rope, you can always find to meet your needs. Control system performance is the most important security and reliability. These are the true value of the property, and you can expect the price to buy a suitable way of security. With a certain product manufacturers to work, he will make you know how to install it. And he will make contact with you and the users, those users have with similar requests.

中文译文

电动卷扬机的控制

对于电动机的控制,我们所知道的最好的方式就是使用由许多点动式按钮组成的简单的手工操作台。而这种操作台在某些应用方面可能仍然是个不错的选择,如一些令人头痛的复杂的控制也可以用。这篇文章讲述了,在你设计、组建或是购买卷扬机控制器之前,你必须对电动机的基本电气设备和你将需要寻址的用户接口命令进行编址。

首先,手动控制台应该是手动控制型的,因此,如果你把你的手指移开按钮,卷扬机就会停车。另外,每个控制工作站都需要配备紧急制动闸,紧急制动闸可以切断卷扬机的所有电源,而不仅仅是控制电路的。仔细想想看,如果卷扬机在该停车时,它却没有停下来,你就确实需要一种故障保障的方法去切断线路的电源。在控制工作台上设置一个关键操作开关,也是一个非常好的主意,特别是在通向工作站的线路不能控制时,就可以用那个开关来控制。

(在设计控制台时,即使是最简单的手工控制台,也要考虑设置由专门人员操作的安全操作按键。)

控制定速电动机

对于一台定速卷扬机的实际控制设备是一台三相起动器。电动机的转向被反向,是通过简单的开关控制相序从A-B-C变换到C-B-A。这些动作被完成,是通过两个三磁极式电流接触器,而且它们是互锁的,所以,它们不可能被同时关闭。NEC公司要求同时拥有过载和短路保护装置。为了保护电动机免受由于机械过载引起的过热的影响,在起动器内要安装热量过载延迟装置。当热量过载延迟装置过热时,它所拥有的双金属长条断开电动机的电源。除此外,还可以选择一台电热调节器可以用缠绕的方式安装在电动机上,它可以用于监控电动机的温度变化。

对于短路保护,我们一般是通过电动机常用的熔断器来实现的。

一台独立的线性电流接触器,被配置的电流接触器应该超过主回路的电流接触器,从而达到冗余的目的。这台电流接触器是由安全电路来控制的,如:紧急制动和越程极限。

我们可以使用限位开关来实现上述的操作。当你到达正常的行程极限位置末端时,卷扬机就会停车,并且你只能够向相反的方向移动卷扬机(即远离极限位置的方向)。这里也需要一个越程限制以防万一,由于电气的或者机械的问题,而使卷扬机的运行超过正常的极限位。如果你碰到越程限制器,线形电流接触器就会打开,因此,卷扬机将无法被驱动超过这个极限位置。如果上述情况发生,就需要请专业的技术人员来检查导致碰到越程限制器的具体原因。然后,你就能够用起动器内部的弹力恢复拨动开关来处理越程的问题,而不是使用跳闸器或是手工切断电流接触器。

变速的必要条件

当然,简单的定速起动器被变速驱动器所取代。这就使事情开始变得有趣起来了!至少,你需要在控制操作台上增加一个速度表盘。操纵杆是一个较好的操作接口,由于它使你对部件的移动有一个更直观的控制。

不幸的是,你不能仅仅从你的本地控制台去发命令控制老式的变速驱动器,此外,你不能希望它在初始阶段,就能安全而可靠的提升与下放设备。大多数的变速驱动器不能实现上述的要求,因为它们并不是设计用来做提升工作的。驱动器需要设置成在制动器松开之前,就能够在电动机上产生扭矩,并且,当停车时,即在扭矩撤销之前,制动器将先动作。

许多年来,直流电动机和驱动器提供了一些普遍的解决方案,如它们在各种速度时都具有良好的力矩特性。对于大多数的卷扬机所需求的大型直流电动机是很贵的,那要比同类型的交流电动机贵得多。虽然,早期的交流驱动器不是非常有用,如它们有一个非常有限速度适用范围,而且仅产生低速小扭矩。如今,随着直流驱动器的发展,低成本而且大量可用的交流电动机的出现,导致了一场交流驱动的革命。

变速交流驱动器有两个系列。变频转换器已经家喻户晓,而且的确很容易使用。这些驱动器将交流转换成直流,然后,再把它转换回交流,转换后的交流已经是不同频率的。如果驱动器产生30Hz的交流,一台正常的60Hz的电动机将以一半的速度运行。从理论上说,这非常好,但是,在实际中,这将会有很多的问题。首先,一台典型的60Hz的电动机在线性频率低于2Hz或是3Hz的区域会出现误差,并且,开始嵌齿(即急推,猛拉),或是停车。这将限制你的速度范围低于20:1,几乎不适应于运行阶段的细微调节。其次,许多低成本的转换器也不能够在低速时提供额定扭矩。使用这些驱动器,将导致急速移动,或是对于提升部件完全的失效,准确地说,当你试图去平稳的提升一台科学仪器时,你不愿看到这样的情况。一些新型的变极器是闭环系统(从电动机获得反馈,提供更加准确的速度控制),并且使电动机将会工作的相当好。

交流驱动器的另一个系列是流量矢量型驱动器。这些元器件要求在电动机的主轴上安装编码器,使用这些编码器会使驱动器可以准确地监控电机电枢的旋转。处理器测定了准确的磁性流量的矢量值,这些值要求使电枢在给定的速度下旋转。这些驱动器允许有无穷大的速度,因此,你实际能够在零速度时就产生额定扭矩。这些驱动器所提供的准确的速度和位置的控制,使这些驱动器在高性能应用方面受到欢迎。

(基于PLC的控制器提供有系统状态和控制选项。这个屏幕展示给操作者全面的访问卡内基霍尔德的九层电梯提升的控制面板。)

基于PLC的系统

一台PLC的全称是可编程序逻辑控制器。首先,PLC的控制器发展到取代了基于五六十年代的工业控制系统的继电器,它们工作在室内的恶劣的工业环境中。这些是模块化的系统,它们具有大量的各种各样的I/O模块。这些模块化的系统可以很容易的实现把半自定义的硬件配置组装起来,而这样得到的配置的价钱也很合理。这些模块包括:位置控制模块,计数器,A/D和D/A转换器,以及各种实体状态或是物理接触闭式输出模块。大量不同类型的I/O元器件和PLC的模块属性使得它成为一条有效的途径去组装自定义和半自定义的控制系统。

对于PLC系统的最大的不足就是缺少真实的大量的显示功能,从而告诉你PLC正在做什么和帮助你对PLC进行编程。

第一台被用于大型娱乐场所的专业的PLC系统之一,是在拉斯维加斯的原米高梅电影制片公司(现在的贝利公司)的搭车和四轮马车系统上。许多的制造商提供了标准的基于PLC的系统和半自动化声学的标志的主机,设定命令行解释器的位置,以及提升控制系统也是可用的。使用标准的模块去组构用户自定义系统的能力是基于PLC的控制器的最大的优势。

高端控制器

对于复杂的传动装置,控制器开始变得复杂,超过了速度,时间以及位置控制。它们包括写出复杂的指令,记录轮廓线的移动,以及处理可以立即运行的多点指令的能力。

许多大型的歌剧院正向着点提升系统的方向发展,在那里为每一条提升绳索配置有一台独立的卷扬机,那些绳索等同于每条电路的调光器。当多台卷扬机

被用来提升单个的部分时,这些卷扬机必须完全的同步,或是载荷能够转移,如此会导致一台单独的卷扬机变得有过载的危险。控制系统必须能够使被选的卷扬机保持同步,或是在一台卷扬机不能够保持与其他卷扬机同步时,能提供高速的同等的停车能力。对于一台典型的高速达240英尺/分钟和一台要保持卷扬机的彼此间的速度误差在1/8分之内的设备,你只有少于三微秒的时间去确认问题,并尝试纠正错误的卷扬机速度,在确定你失败后,你起动组中所有卷扬机的停车。这将需要大量计算,快速I/O接口,以及好用的写入软件。

对于大型的绳索控制系统有两种非常不同的解决方法。首先是,使用单独的控制台,对于一般的问题而言,这样的控制台应该安装在适合于操作者视角的位置。然而,这不仅不能够从一个角度到另一个角度观察,而且还不可以从一条指令到另一条指令的控制。这些困难已经被部分解决。通过使用安装在不同位置的视频摄像机,而且这些摄象机连接于三维屏幕图形,这些图形使得操作者可以从任意的视角去观察在三个坐标方向上的预期的绳索运动。这些可以使得操作者,从一个适合他在实际的操作台处的视角,或是实际的闭环电路照相机的视角,来观察在屏幕上的绳索的运动。对于有内部关联的部件的复杂的移动,上述的观察使得实现控制和查出故障原因变得更加简单。

另一个解决的方案就是分布式系统,这个系统使用了多个轻便的控制台。这将允许不同的操作者以同样的方式控制传动装置的不同方面,我们已经改进了手动控制装置。一个生动的例子,就是在伦敦中部一个蔬菜花卉市场的皇家歌剧院使用了上述的方案,在那里用十个控制台控制着240台电动机。每个控制台有五个录音重放装置,并且已经被开启,以便于每台电动机被指派给一个单独的控制台。一位操作者和一个控制台就能够控制所有的装置,但是,常常是一个控制台可能是运行台幕的提升,另一个控制台是控制台上的传动装置,以及第三个控制台被用来在后台将必要的背景画面放下。

(刃口式轻便的控制台允许多位操作者从最优点出发来控制机器的运动,并且提供三维图象的显示。)

结论

有巨大变化的绳索控制系统,已经从按钮式的工作站发展到复杂的多用户的计算机化的控制系统。当要购买绳索控制系统时,你总是可以找到满足你需要的。控制系统最重要的性能是安全性和可靠性。这些是有真实价值的性能,而且你会期望能以一个合适的价格买到这样的安全性。与某个确定的产品制造商共事,他会使你知道如何进行安装。而且,他将会让你和用户接触,那些用户有着与类似的要求。

旅游服务贸易外文翻译文献

旅游服务贸易外文翻译文献(文档含英文原文和中文翻译)

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