设备状态监测系统的DL/T860建模及智能化设计

状态监测是获取设备运行状态的技术手段,是检修与运维的重要信息来源。根据面向智能电网的设备状态监测系统智能化的建设及改造需求,给出了基于DL/T860标准通信规约的从变电子站到主站的全面设计方案,解决了IED的标准化、互操作性和互换性问题,实现了信息共享,为生产管理、状态检修、智能电网决策分析提供所需要的数据,为实用化的状态监测技术应用、选型积累经验。     

基于IEC 61850的变电站二次系统工程调试与质量控制

针对基于IEC 61850的变电站二次系统,通过分析其技术来源、技术作用以及应用目的,探讨了变电站智能电子设备（intelligent electronic device,IED）集成基础上的调试工作及其传承。根据二次系统与传统系统的技术特点、调试工作差异,讨论了二次系统组态调试和工程调试的目标及其区别与联系。根据变电站工程调试的内涵与目的,综合二次系统结构以及功能构成特点,建设性论述了二次系统的工程调试方法以及相应的质量控制策略,并注重了调试项目的过程完整性与整体质量控制。     

支持大规模智能电网的数据存储方法

针对大规模智能电网中的监测数据具有海量性、实时性、动态性等特点,提出一种以数据为中心的支持大规模智能电网的数据存储方法:海量动态数据的分层扩展存储机制。首先,采用扩展哈希编码方法动态增加存储节点,避免突发、频发事件数据的丢失,增强系统的可用性;然后,采用多阈值级别方法将数据分散到多个存储节点上,避免出现存储热点问题,实现负载均衡。实验结果表明,分层扩展存储机制能够最大限度地满足海量数据的存储需求,获得较好的负载均衡,并且使总能耗最低,有效地延长了网络的生命周期。     

IEC61850配置的工程应用探讨

随着数字化变电站的推广以及IEC61850标准的应用,61850的配置模型也在逐步的走向工程化实践.要能很好地应对大量的工程应用,首先是配置模型的标准理解尤为重要,其次就是如何跟实际结合好.从标准相关内容的理解,同时结合工程应用的实际出发,分析其合理的应用模式,探讨提出了变电站自动化系统工程实际中的IEC 61850配置方法、工具及其功能的描述,同时总结一些实际经验,与同行交流.     

基于IED的微网关联区域保护研究

为克服微网中保护整定困难、选择性不足等带来的问题,提出了基于智能电子设备的微网关联区域保护的方法。根据微网的5种区域划分思想,提出了区域属性的概念,并采用IED将微网5种区域划分得更为明确,制定了各种区域对应的故障判定原理及方法,利用分布式决策保护策略,确定了微网关联区域保护方案及IED保护流程,并通过PSCAD/EMTDC仿真结果验证了本保护的有效性。     

A comparative study of CrNx coatings Synthesized by dc and pulsed dc magnetron sputtering

Chromium nitride (CrN_x) coatings were prepared by reactively sputtering chromium metal target with various nitrogen flow rate percentages (f_N2) using a closed field unbalanced magnetron sputtering system operated in dc and middle frequency pulsed condition (100 kHz and 50% duty cycle). In this study, plasma examination proved that a large amount of ions with a wide range of ion energies (up to 65 eV and mainly from 10-30 eV region) was identified in the pulsed plasma compared to the low ion flux and energy (0-10 eV) in a dc discharged plasma. The results showed that the phase structure of CrN_x coatings was changed from nitrogen doped Cr(N) to pure β-Cr₂N, and to a mixture of β-Cr₂N and c-CrN and then to pure c-CrN phases with an increase in the f_N2 in both dc and pulsed conditions. However, the pulsed CrN_x coatings exhibit lower N concentrations than dc CrN_x coatings prepared under the same f_N2, which leads to the existing of β-Cr₂N phase within a wide range of f_N2 (30-50%). In comparison with the typical large columnar structure in the dc sputtered coatings, the pulsed CrN_x coatings exhibit dramatic microstructure improvements which benefited from the improved plasma density and ion bombardment from the pulsed plasma, where the super dense and nearly equi-axial structures were observed in a wide range of f_N2. The microstructure improvements contributed to the enhancements in the hardness and wear resistance of pulsed CrN_x coatings. In the pulsed CrN_x coatings, the hardness values were above 30 GPa when the f_N2 is in the range of 30-40%, which is related to the formation of the β-Cr₂N phase. With the formation of a mixture of β-Cr₂N and c-CrN phases in the coatings deposited with 40-50% f_N2, a low COF of 0.36 and wear rate of 1.66 × 10^− 6 mm³ N^− 1 m^− 1 can be achieved.     

基于调度数据网的变电站智能设备远程维护系统

随着变电站综合自动化技术的应用与发展,大量无人值守的变电站陆续投入运行。对变电站内智能型装置(如RTU、测控单元)的有效维护是确保调度自动化系统正常发挥作用的基础。文章介绍了一种基于数据通信网的灵活实用的远程维护方案,利用调度自动化通信技术及SCADA技术,综合多种智能算法,实现设备故障的及时发现和诊断处理,为电网调度自动化系统的可靠运行提供技术保障。     

Evaluation of Y2O3 surface machinability using ultra-precision lapping process with IED

Prospects of Y₂O₃ have been more extended as a great promising and creditable material for optical, electronic and mechanical purposes. Y₂O₃ has been more observed as a fine ceramic which has great material properties: high light transparency, excellent thermal resistance and chemical inertness. But in terms of effective application of Y₂O₃, its hard and brittle nature needs to be overcome during the surface machining process. Therefore, the surface machining control of Y₂O₃ should be conducted carefully. The evaluation for stable and continuous machining should also be investigated in various industrial fields as there are only limited studies on the subject. The lapping process with in-process electrolytic dressing (IED) is widely used for surface machining of hard and brittle materials. In this study, Y₂O₃ surface machinability was evaluated by using the ultra-precision lapping process with IED method by changing three major variables: applied force, wheel speed and machining time. The most suitable value of Ra 92nm surface roughness was acquired with smooth surface quality from the following machining condition: 7kg of applied force, 60rpm of wheel speed and 30minutes of machining time. After the lapping process, the machining tendency and surface characteristics were analyzed with fracture toughness and Vickers hardness for the evaluation of Y₂O₃ surface machinability. This paper was recommended for publication in revised form by Associate Editor Dae-Eun Kim Eun-Sang Lee received B.S. and M.S. degrees in Mechanical Engineering from INHA University in 1985 and in 1987. After that time, he received a Ph.D. degree from Korea Advanced Institute of Science and Technology in 1998. Dr. Lee is currently a Professor at the School of Mechanical Engineering at INHA University in Incheon, Korea. His research fields are ultra-precision manufacturing, electro chemical micro machining and development of semiconductor wafer polishing system.     

基于CAN网采用滑动窗口技术传输信息

针对CAN网传输智能电子设备(IED)信息速度慢的现状,提出基于CAN网结构采用滑动窗口技术实现IED内部各通信插件之间信息交换的方法,将以太网TCP/IP协议中的"一问多答"、"断点续传"等先进技术应用到CAN网,可使IED大量的描述信息准确、快速交换,尤其是IED长时间故障录波后,可快速上传到分析终端进行故障诊断.对比试验发现,与传统的"停止一等待协议"相比,"滑动窗口协议"传输电网故障信息更加高效,同时"滑动窗口协议"配置灵活,通过改变窗口尺寸,即可兼容"停止一等待协议".     

基于IEC 61850标准中ACSI模型的实现

IEC 61850标准定义了抽象数据模型和服务模型,规定了对象和服务模型到制造报文规范（MMS）等特定协议的映射方法。文章以基于IEC 61850标准建立的智能电子设备数据结构为基础,提出了实现抽象通信服务接口的设计方法,实验证明,该方法能更好地实现IEC 61850标准与MMS体系的相互独立。