1、外文文献原稿和译文原 稿Industrial and collaborative control systems a complementary symbiosisLooking at todays control system one can find a wide variety of implementations. From pure industrial to collaborative control system (CCS) tool kits to home grown systems and any variation in-between. Decisions on the
2、 type of implementation should be driven by technical arguments Reality shows that financial and sociological reasons form the complete picture. Any decision has its advantages and its drawbacks. Reliability, good documentation and support are arguments for industrial controls. Financial arguments d
3、rive decisions towards collaborative tools. Keeping the hands on the source code and being able to solve problems on your own and faster than industry are the argument for home grown solutions or open source solutions. The experience of many years of operations shows that which solution is the prima
4、ry one does not matter, there are always areas where at least part of the other implementations exist. As a result heterogeneous systems have to be maintained. The support for different protocols is essential. This paper describes our experience with industrial control systems, PLC controlled turn k
5、ey systems, the CCS tool kit EPICS and the operability between all of them.InroductionProcess controls in general started at DESY in the early 80th with the installation of the cryogenic control system for the accelerator HERA (Hadron-Elektron-Ring-Anlage). A new technology was necessary because the
6、 existing hardware was not capable to handle standard process controls signals like 4 to 20mA input and output signals and the software was not designed to run PID control loops at a stable repetition rate of 0.1 seconds. In addition sequence programs were necessary to implement startup and shutdown
7、 procedures for the complex cryogenic processes like cold boxes and compete compressor streets. Soon it was necessary to add interfaces to field buses and to add computing power to cryogenic controls. Since the installed D/3 system1 only provided an documented serial connection on a multibus board,
8、the decision was made to implement a DMA connection to VME and to emulate the multibus boards functionality. The necessary computing power for temperature conversions came from a Motorola MVME 167 CPU and the field bus adapter to the in house SEDAC field bus was running on an additional MVME 162. Th
9、e operating system was VxWorks and the application was the EPICS toolkit. Since this implementation was successful it was also implemented for the utility controls which were looking for a generic solution to supervise their distributed PLCs.A slection of process control systems at desyDCS (D/3) As
10、a result of a market survey the D/3 system from GSE was selected for the HERA cryogenic plant. The decision was fortunate because of the DCS character of the D/3. The possibility to expand the system on the display- and on the I/O side helped to solve the increasing control demands for HERA. The lim
11、iting factor for the size of the system is not the total number of I/O but the traffic on the communication network. This traffic is determined by the total amount of archived data not by the data configured in the alarm system. The technical background of this limitation is the fact that archived d
12、ata are polled from the display servers whereas the alarms are pushed to configured destinations like alarm-files, (printer) queues or displays. SCADA Systems with DCS Features (Cube) The fact that the D/3 system mentioned above had some hard coded limitations with respect to the Y2K problem was for
13、cing us to look for an upgrade or a replacement of the existing system. As a result of a call for tender the company Orsi with their product Cube came into play 2. The project included a complete replacement of the installed functionality. This included the D/3 as well as the integration of the DESY
14、 field bus SEDAC and the temperature conversion in VME. The project started promising. But soon technical and organizational problems were pushing the schedule to its limits which were determined by the HERA shutdown scheduled at that time. The final acceptance test at the vendors site showed dramat
15、ic performance problems. Two factors could be identified as the cause of these problems. The first one was related to the under estimated CPU load of the 6th grade polynomial temperature conversion running at 1 Hz. The second one was the additional CPU load caused by the complex functionality of the
16、 existing D/3 system. Here it was underestimated that each digital and analog input and output channel had its own alarm limits in the D/3 system. In a SCADA like system as Cube the base functionality of a channel is to read the value and make it available to the system. Any additional functionality
17、 must be added. Last not least the load on the network for polling all the alarm limits typically for a SCADA system was also driving the network to its limits. Finally the contract with Orsi was cancelled and an upgrade of the D/3 system was the only possible solution. It was finally carried out in
18、 march 2003.In any case it should be mentioned that the Cube approach had the advantage of a homogeneous configuration environment (for the Cube front end controllers) compared with heterogeneous environments for pure SCADA systems.SCADA (PVSS-II)The H1 experiment at the HERA accelerator decided to
19、use PVSS-II for an upgrade of their slow control systems3. The existing systems were developed by several members of the H1 collaboration and were difficult to maintain. The decision to use PVSS as a replacement was driven by the results of an extensive survey carried out at CERN by the Joint Contro
20、ls Project 4. PVSS is a pure Supervisory And Data Acquisition System (SCADA). It provides a set of drivers for several field buses and generic socket libraries to implement communication over TCP/IP. The core element is the so called event manager. It collects the data (mostly by polling) from the I
21、/O devices and provides an event service to the attached management services like: control manager, database manager, user interface, API manager and the built in HTTP server. The PVSS scripting library allows to implement complex sequences as well as complex graphics. Compared with other SCADA syst
22、ems PVSS comes with one basic feature: it provides a true object oriented API to the devices data. One major disadvantage of SCADA systems is the fact that two databases, the one for the PLC and the one for the SCADA system must be maintained. Integrated environments try to overcome this restriction
23、. EPICS EPICS has emerged at DESY from a problem solver to a fully integrated control system. Starting from the data collector and number cruncher for the cryogenic control system, EPICS made its way to become the core application for the DESY utility group. In addition it is used wherever data is a
24、vailable through VME boards or by means of Industry Pack (IP) modules. For those cryogenic systems which are not controlled by the D/3 system EPICS is used with its complete functionality. In total about 50 Input Output Controller (IOC) are operational processing about 25 thousand records. 1 EPICS a
25、s a SCADA System The utility group ( water, electrical power, compressed air, heating and air conditioning) is using a variety of PLCs spread out over the whole DESY site. EPICS is used to collect the data from these PLCs over Profibus (FMS and DP) and over Ethernet (Siemens H1 and TCP). The IOCs pr
26、ovide the interfaces to the buses and collect the data. The built in alarm checking of the EPICS records is used to store and forward alarm states to the alarm handler (alh) of the EPICS toolkit. In addition tools like the channel archiver and the graphic display (dm2k) are used. The default name re
27、solution (by UDP broadcast) and the directory server (name server) are used to connectclient and server applications over TCP. All of these are basically SCADA functions. The textual representation of all configuration files ( for the IOC, the graphic tool, the alarm handler and the archiver) provid
28、es a flexible configuration scheme. At DESY the utility group has developed a set of tools to create IOC databases and alarm configuration files from Oracle. This way the controls group provides the service to maintain the EPICS tools and the IOCs while the users can concentrate on the equipment bei
29、ng controlled. 2 EPICS as a DCS System Besides the basic components of a SCADA system EPICS also provides a full flavoured Input Output Controller (IOC). The IOC provides all of the function a DCS system requires, such as: a standard set of properties implemented in each record, built in alarm check
30、ing processed during the execution of each record; control records like PID etc.; configuration tools for the processing engine. The flexible naming scheme and the default display and alarm properties for each record ease the connection between the operator tools and the IOCs. The flexible data acqu
31、isition supports the poll mode as well as the publish subscribe mode. The latter reduces the traffic drastically. Conclusions Depending on the size and the requirements for a controls project the combination of commercial solutions and solutions based on a collaborative approach is possible in any r
32、ate between 0 and 100 percent. This applies for all levels from implementation to long term support. Special requirements on safety issues or a lack of manpower might turn the scale commercial. The necessity to interface special hardware, special timing requirements, the having the code in my hands
33、argument or the initial costs for commercial solutions will turn the scale collaborative. As long as collaborative approaches like EPICS stay up to date and run as stable and robust as commercial solutions, both will keep their position in the controls world in a complementary symbiosis.译 文工业控制系统和协同
34、控制系统当今的控制系统被广泛运用于许多领域。从单纯的工业控制系统到协同控制系统（CCS） ，控制系统不停变化，不断升级，现在则趋向于家庭控制系统，而它则是这两者的变种。被应用的控制系统的种类取决于技术要求。而且，实践表明，经济和社会因素也对此很重要。任何决定都有它的优缺点。工业控制要求可靠性，完整的文献记载和技术支持。经济因素使决定趋向于协同工具。能够亲自接触源码并可以更快速地解决问题是家庭控制系统的要求。多年的操作经验表明哪个解决方法是最主要的不重要，重要的是哪个可行。由于异类系统的存在，针对不同协议的支持也是至关重要的。本文介绍工业控制系统，PlC controlled turn key
35、系统，和 CCS 工具，以及它们之间的操作。引言80 年代早期，随着为 HERA(Hadron-Elektron-Ring-Anlage)加速器安装低温控制系统，德国电子同步加速器研究所普遍开始研究过程控制。这项新技术是必需的，因为但是现有的硬件没有能力来处理标准过程控制信号，如 4 至 20 毫安的电流输入和输出信号。而且软件无法在 0.1 秒的稳定重复率下运行 PID 控制回路。此外，在实现对复杂的低温冷藏系统的开闭过程中，频率项目显得尤为重要。有必要增加接口解决总线问题并增加运算能力，以便于低温控制。因为已安装的 D / 3 系统1 只提供了与多总线板串行连接，以实现 DMA 与 VME
36、 的连接并用其模拟多总线板的功能。温度转换器的计算功能来自一个摩托罗拉 MVME 167 CPU 和总线适配器，以及一个 MVME 162 CPU。其操作系统是 VxWorks，而应用程序是EPICS。由于对它的应用相当成功，其还被运用于正在寻找一个通用的解决方案以监督他们的分布式 PLC 的公共事业管理。德国电子同步加速器研究所对过程管理系统的筛选集散控制系统（D/ 3）：市场调查表明：来自 GSE 的 D / 3 系统被 HERA 低温冷藏工厂选中。因为集散控制系统（D/ 3）的特性，所以这决定很不错。在展示端和 I / O 端扩展此系统的可能将有助于解决日益增加的 HERA 试验控制的要
37、求。制约系统的大小的因素不是 I / O 的总数，通信网络的畅通与否。而通信网络的畅通与否取决于不存档的数据总量，不取决于报警系统中配置的数据。拥有 DCS 特点（Cube）的 SCADA 系统：相对于 Y2K 问题促使我们寻找一个升级版或者代替版来代替现有的系统而言，以上提到的 D / 3 系统有一些硬编码的限制。由于急需给 Orsi 公司提供他们的产品，Cube 开始起作用了2。该项目包括安装功能的完全更换。这包括 D / 3，以及德国电子同步加速器研究所的集成总线 SEDAC 和 VME 的温度转换器。该项目很有前景。但是因为 HERA 试验原定时间是有限制的，所以技术问题和组织问题也迫
38、使计划提前。在供应商网站上的最后验收测试又出现了戏剧性的性能问题。有两个因素引起了这些问题。第一个跟低估在 1 赫兹运行的 6 级温度转换器的 CPU 负荷有关。第二个由现有 D / 3 系统复杂的功能造成的额外负荷引起的。每个数字和模拟输入和输出通道在 D / 3 系统里的自身报警限值也被低估了。所有的附加功能都必须添加进去。最后，所有网络负载的报警限值，尤其是 SCADA 系统，也促使网络生成了限制。最后，与 Orsi 公司的合同被取消了。升级的 D / 3 系统是唯一可能的解决办法。在 2003 年 3 月，此系统最后被付诸实践。现在，相比“纯粹”SCADA 系统的异质环境，Cube 有
39、同质配置环境的优势。SCADA（PVSS -）：在 HERA 加速器上的 H1 实验中，实验人员为升级他们的低速控制系统，决定使用 PVSS -。现有的系统是由 H1 合作组的几名成员开发的，而现在却难以维持了。在 CERN 由联合控制项目4进行的广泛调查促使他们做出使用 PVSS 作为代替品的决定。PVSS 是一个“纯粹”的监控和数据采集系统（SCADA 系统） 。其核心元素叫做事件管理器。它收集的数据主要是由 I/ O 设备提供。它还提供附加的管理服务，如：控制经理，数据库管理，用户界面，API 经理以及在建的 HTTP 服务器。该 PVSS 脚本库允许执行复杂的序列以及复杂的图形。相比其
40、他 SCADA 系统 PVSS带有一个基本特点：它提供了 API 给设备的数据。SCADA 系统的一个主要缺点是其中的两个数据库，一个为 PLCs 服务，另一个为 SCADA 系统服务，这两个数据库必须维持。集成环境将努力克服这个限制。EPICS：在德国电子同步加速器研究所，EPICS 从问题解决系统演化成了全集成控制系统。从成为低温控制系统的数据收集器和数量控制器，EPICS 成为了德国电子同步加速器研究所公用事业集团使用的核心系统。此外，通过 Industry Pack（IP）模块的手段，它还能运用于通过 VME 板卡的任何数据。 EPICS 通过其完整的功能，运用于没有由 D / 3 系
41、统控制的低温冷藏系统。所有大约 50 个输入输出控制器运作大约25000 业务处理记录。作为一个 SCADA 系统的 EPICS：该公共事业组（水，电，压缩空气，加热和调温）使用各种散布在整个德国电子同步加速器研究所网站上的 PLC。IOC 向客户提供接口并采集数据。此外，如通道归档和图形显示（dm2k） 会被使用。默认名决议和目录服务器（域名服务器）用于连接 在 TCP 客户端和服务器应用程序。所有这些都是基本的 SCADA 功能。所有的配置文件（图形工具，报警处理程序和归档）提供了一种灵活的配置方案。德国电子同步加速器研究所公用事业集团已制定了一套工具来创建 IOC 数据库和配置文件。这样
42、，控制组提供的服务保持 EPICS 工具，而用户可以精力集中在被控制的设备上了。作为一个 DCS 系统的 EPICS：作为 SCADA 系统的基本组成部分，EPICS 还提供完整的输入输出控制器（IOC） 。IOC 提供所有功能 DCS 系统要求，如：实施每个记录的标准的属性；执行每个记录时的报警检查过程；控制记录，如 PID。灵活的命名方案，默认的显示和每个记录的报警属性缓和了运作工具和 IOC 之间的连接。灵活的数据采集模式，支持调查模式以及发布订阅模式。后者大大降低了信息拥堵的情况。实施策略表现完各种可能的控制方法后，该是查看控制系统的完成情况了。从 I / O 级开始，他们必须决定是否
43、需要商业解决。特殊的 I / O 不总是需要定制解决方案。信号可以被转换成标准的信号，但是这并不适用于所有的信号。信号水平可能需要定制的发展，这必须纳入整体控制架构。信号不能被连接到标准 I / O 接口，也许有可能发展的 I / O 控制器的 允许实施现场总线接口，这能够整合商业控制系统。整合水平是不可能定制前端控制器，如 VME，开始发挥作用了。Turn Key 系统在工业中，有个明显的趋势就是产生了 Turn Key 系统。它允许对整个系统进行模块化设计。个别元件分包给几个公司进行本地测试。一旦交付施工现场，验收测试就已经过去了，第二个阶段，整合融入全球控制系统的子系统开始。虽然控制回路
44、的详细规格等，是现在子系统合同的一部分。客户必须明确多少信息子系统可以被使用。大多数 Turn Key 系统与 PLC 一起交付使用。瑞士光源（SLS）的建立过程已显示，这也是基于 I/ O 系统运行的 VME 运行 CCS 的，这样才可以成功启用6。基于系统的 PLC基于系统的 PLC 是 Turn Key 系统成果。下一个明显的方法看起来可能是除了商业 PLC，就是商业 SCADA 系统。优势就是明显和 PLC 一样：没有稳定的软编程器，仅有配置，支持和良好的文件系统。在德国电子同步加速器研究所，我们成功地建立了控制组和公共事业组之间的关系。尽管是 EPICS 编码，但其最大的优势就是能调
45、整双方的特殊要求。工业解决方案一旦工业开始支持协作控制系统，CCS 的解决方案和商业之间的差异将渐渐变小。在 KEK，公司签订合同为 KEK-B 升级提供程序员。这些程序员进行了书面驱动程序和应用程序代码的 EPICS 培训。因此，KEK-B 控制系统是工业用和民用升级软件的混合体。这是 CCS 实施中工业参与的另一个例子。成本自从个人电脑出现后， “一台个人电脑的总成本是多少？”这样的问题一直使人忙碌。所有的答案不尽相同的极端。现在的问题什么是一个控制系统的 TCO 可能作出类似的结果。如果你进入商业领域，你要支付的初始证照费用，而通常这是由供应商或分包商支付的，你付钱进行的软件支持，可能或
46、可能不会包括你更新证照的费用。如果你去寻求合作方式，你可能与公司签合同或完成一切。而“时间与金钱说”在工业中同样成立。你亲自完成可能更自由灵活，但是有点难度。你 可以依靠合作，以提供新的功能和版本，或者你可以为自己作出贡献。主要的区别就是要为控制系统计入长期成本。德国电子同步加速器研究所粗略估计，控制应用程序，如支持商业模式的 D / 3，和支持协作模式的 EPICS 几乎是相同的。在该软件支持和升级证照的费用，相当于 1.5 倍的 FTEs 。FTEs 是关于人力资源的内容，对于支持新的硬件和升级EPICS 是必要的。结论根据控制项目不同的规模和要求，整合的商业解决方案和基于协作应用程序的解决方案在百分之零到一百都可能。这适用于长远的技术支持。在安全问题上的特殊需要或人力资源的缺乏可能会扩大商机。接口专业硬件，掌控在手的谈判或商业解决方案的初始成本有可能促使大规模的合作。只要如 EPICS 的协作途径，保持最新并运行如商业方案一样稳定和强劲，它们就能在互补共生的控制世界中占有一席之地。
