DIGITAL CONTROL SYSTEMS FOR HIGH-VOLTAGE SUBSTATIONS - PART II

James Propst; Mike Dood

摘要

In order to make the best use of the available features within the protective relays and also to leverage the knowledge that the Western personnel already had with the relays, the control and monitoring functions are now performed by the relays and communications processors. This monitoring and control had previously been performed by less-reliable PLCs and RTUs. The microprocessor relays are now responsible for tripping and closing either via local or via remote operators, or via automation logic settings. The relays are also used wherever practical to bring back status and analog operational and maintenance data from substation apparatus.rnThis eliminated many discrete components such as switches and auxiliary relays, and the associated wiring. Fewer components dramatically increased the quality and reliability of the logic processes by moving them into highly reliable IEDs designed for use in mission-critical applications.rnThe need to replace all the damaged copper cable in the substation provided the opportunity to evaluate installing fiber. The analysis proved that fiber is an economical solution and provided all the many benefits of using fiber instead of discrete pairs of copper control conductors for each control and monitoring function. Innovative features in the specific products chosen also provide constant monitoring and immediate alarm and notification if the cables to the field I/O are damaged. This is not available via traditional copper cable methods.rnThe use of multifunctional microprocessor relays resulted in a large reduction in the amount of space required in the control house. This translates into a cost savings during installation, reduced maintenance cost and effort, and higher reliability, because the design uses fewer devices, components, and wires.rnThe new system provides much more measured and calculated information about the power system for use by operating, maintenance, and engineering personnel than was previously available. Western makes good use of these data in part due to the fact that it is easily accessed through a common userrninterface. In addition to the power system data, the microprocessor relays provide a wealth of self-test and real-time diagnostic information that makes it easy for operating and engineering personnel to troubleshoot system events. Using these data, Western personnel ensure that schemes and settings are correct.rnWhile the DCS system essentially paid for itself in direct savings, it also creates an infrastructure for new and emerging technologies such as RCM. The IEDs connected via fiber to Western's intranet have the capability to provide more information than they currently use. As the industry learns how to use this information, Western is poised to easily take advantage of new technology.rnFinally, the familiarity with computers and the proliferation of available software packages has made them a logical consideration for the substation. Until recently, applications had to be chosen carefully because both desktop and industrial computers exhibit very low MTBF, or mean time between failures. MTBF is a measure of the relative reliability of a device and is used to choose between devices during design and selection. Features such as redundant power supplies and easily exchanged hard drives make computers marginally more reliable but also obviously increase the required amount of maintenance. Western offset this low MTBF by installing redundant HMIs with redundant hard drives and redundant power supplies. The advent of a new class of more robust devices, rugged computers, will improve individual computer reliability and will eliminate the need for a redundant computer system.

机译：为了充分利用保护继电器中的可用功能，并利用西方人员已经具备的继电器知识，现在由继电器和通信处理器执行控制和监视功能。这种监视和控制以前是由不太可靠的PLC和RTU进行的。现在，微处理器继电器负责通过本地或远程操作员或通过自动化逻辑设置来跳闸和合闸。这些继电器还用于从变电站设备恢复状态以及模拟运行和维护数据的地方。这消除了许多分立组件，例如开关和辅助继电器以及相关的布线。更少的组件将其移入设计用于关键任务应用的高度可靠的IED中，从而显着提高了逻辑过程的质量和可靠性。替换变电站中所有损坏的铜缆的需求提供了评估安装光纤的机会。分析证明，光纤是一种经济的解决方案，并为每个控制和监视功能提供了使用光纤代替离散的成对铜控制导体的所有优点。如果连接到现场I / O的电缆损坏，则所选特定产品中的创新功能还可以提供持续的监视，即时警报和通知。这是通过传统的铜缆方法无法实现的。rn多功能微处理器继电器的使用大大减少了控制室所需的空间。由于设计使用较少的设备，组件和电线，因此可以节省安装过程中的成本，减少维护成本和工作量并提高可靠性。rn新系统提供了更多有关电源系统的经过测量和计算的信息，可通过操作来使用，维护和工程人员比以前更多。 Western充分利用了这些数据，部分原因是可以通过公共用户界面轻松访问这些数据。除了电力系统数据外，微处理器继电器还提供大量的自检和实时诊断信息，使操作和工程人员可以轻松地对系统事件进行故障排除。西方人员使用这些数据可以确保方案和设置正确。虽然DCS系统本质上是直接节省了成本，但它也为RCM等新兴技术创建了基础设施。通过光纤连接到Western的Intranet的IED具有提供比其当前使用的更多信息的能力。随着行业学习如何使用这些信息，西方公司已准备好轻松利用新技术。最后，对计算机的熟悉和可用软件包的增加已使它们成为变电站的逻辑考虑。直到最近，由于台式计算机和工业计算机的MTBF都非常低，或者平均故障间隔时间很短，因此必须仔细选择应用程序。 MTBF是衡量设备相对可靠性的一种指标，用于在设计和选择期间在设备之间进行选择。冗余电源和易于更换的硬盘驱动器等功能使计算机在某种程度上更可靠，但显然也增加了所需的维护量。 Western通过安装带有冗余硬盘驱动器和冗余电源的冗余HMI来弥补MTBF较低的问题。新型更强大的设备，坚固耐用的计算机的出现将提高单个计算机的可靠性，并消除对冗余计算机系统的需求。

DIGITAL CONTROL SYSTEMS FOR HIGH-VOLTAGE SUBSTATIONS - PART II

摘要

著录项

相似文献

相关主题

期刊订阅