Research on Reliability of Relaying Protection in Smart Substation

Research on reliability of relaying protection in smart substation not only has a positive effect on the rational configuration scheme of relaying protection in smart substation, but also can promote the stability and safety of the overall operation of power system. There are many reliability strategies for relaying protection in smart substation. In practice, the key points of relaying protection should be clarified. Based on the reality, the protection configuration should be strengthened;the voltage limited delay should be used for protection, and the protection configuration scheme of actual lines should be paid attention to, so as to improve the reliability of relaying protection in smart substation and promote the realization of stable and sustainable development of power system and smart substation.

Research on Testing Technologies of Network System in Smart Substations

The network structures of smart substations and the characteristics of industrial Ethernet switches are analyzed.The testing technologies of network systems based on smart substations are specifically elaborated.A viewpoint is proposed that special testing policy&method of smart substation networks should be followed,so that the results can reveal the real network data exchange performance of the whole station.This view ensures the safety and stability of smart substations and lays a foundation for future upgrades and expansions.

Modeling of IEEE1588 on OPNET and Analysis of Asymmetric Synchronizing Error in Smart Substation

The IEEE1588 network time synchronization, matched with smart substation information network transmission, is becoming the next generation advanced data synchronization of the smart substation. It is known that the inherent asymmetry error of the network synchronization approach in the smart substation is highlighted, which is concerned particularly. This paper models the synchronization process of the IEEE1588 based on the communication simulation software of OPNET Modeler. Firstly, it builds the models of master-slave clock, IEEE1588 protocol and network synchroniza- tion model, and analyzes the composition and influencing factors of the asymmetry error. Secondly, it quantitatively analyzes the influence of the synchronous asymmetric error of the IEEE1588 affected by the network status differences and the clock synchronization signal transmission path differences. Then its correction method is analyzed, in order to improve the IEEE1588 synchronization reliability and gives the solutions to its application in smart substation.

Dynamic Testing of an IEC 61850 Based 110 kV Smart Substation Solution

This paper presents the dynamic simulation and testing to verify the smart substation solutions designed for a brown field 110 kV retrofitting project. An IEC 61850 based aotomation design, transitioning the conventional substation into a smart substation, where existing current/voltage transformers remain in service, and smart Field Apparatus Interface Units (FAIUs) are utilised to bridge the conventional primary system to the IEC 61850 based secondary system. While outdoor switchgears and field instrument transformers are equipped with FAIUs, MV indoor switchgears are installed with IEDs mounted on the top. Direct point-to-point connections serve as process buses, and a single PRP/RSTP LAN is employed at station bus level. Extensive dynamic simulation and testing were conducted in the Smart Substation Technologies Lab, and test results show the smart substation performance meets and exceeds the substation reliability requirement.

A Smart Substation Field Secondary Device Testing Technique Based on Recurrence Principle

According to the demand of substation secondary device dynamic performance testing, a smart substation field testing technique based on recurrence principle is proposed in the paper, and the characteristics of smart substation secondary device digitization and information sharing are used by the technique. The principle of testing technique is as follow: the digital simulation model is constructed on the basis of the substation’s actual construction, then the simulating data highly similar to substation’s actual electric quantity transient process is generated, at last, the substation digital secondary device can be tested by using data “recurrence” technique. The testing technique is verified and applied by constructing testing system, the application results show that the technique can effectively perform field test on the dynamic performance of digital secondary device, and the technique has good engineering implementation and application value.

Auxiliary-Service Smart Monitoring Solutions: A Study in High-Power Substations in Colombia

The present study assesses the possibility of implementing an auxiliary-service smart monitoring solution at power substations. The solution is intended to improve substation indices in terms of accident rates and undesired events that result from initial incidents associated to failure of the Direct Current systems in charge of supporting the operation of protection elements. In recent years in Colombia, substation fires have been reported, and auxiliary services have been identified as a potential initial cause of these unfortunate events. In fact, in Bogotá (Capital city of Colombia), in the last decade, incidents occurred at four high-power substations, and the potential failure cause was associated to the operation of auxiliary services, according to the criteria of experts in the electrical sector. The present study illustrates how a monitoring system substantially improves the lifecycle of battery banks in a three-year period (8% lifecycle improvement together with an increase in reliability of the system by allowing more time for failure identification). The estimated financial benefits reach 2 million US dollars and stem from reducing the frequency of explosions at substations by 11%. The technology in question is assessed and recommended based on the results of various experiments, where various monitoring methods are tested, also considering the operation and maintenance costs that constitute an appropriate lifecycle evaluation.

Requirements and Proposed Solutions for Future Smart Distribution Substations

This paper proposes a novel solution for the secondary system of a primary distribution substation. First an evaluation is made of the changes that are to be expected for distribution substations in the future. Distributed generation, electric vehicles and other active resources will change the behavior of the distribution network in a manner that will have a great deal of implications for distribution substations. The question is how the role of the distribution substations will change when the visions of smart grids become reality. The proposed solution consists of bay level protection and control IEDs forming the backbone of the secondar？, system. The functionality is complemented with a substation level Station Computer, providing value added and advanced functionality. In addition required communication and time synchronization methods are presented. A life cycle cost evaluation is also performed on the proposed solution, and it is compared with the current dominant concept based exclusively on bay level devices.

China’s Three Gorges Reservoir Area of Intelligent Substation Project Supervision Work Method Is Discussed in This Paper

The ecological environment promotes the construction of smart grids, while the smart substation is the key to the construction of smart grids. Based on the supervision of the Zigui 220 KV smart substation project in the Three Gorges Reservoir Region of China, this paper studies how to well create the supervision for the smart substation project construction. With the research focus of “four-control, two-management and one-coordination” in the supervision and according to the problems and experience in the project construction, some reasonable suggestions are put forward, and then the accumulated methods and experience by supervisors when they are engaged in the supervision for the smart substation project construction are summarized.

Research on Cyber-Physical Modeling for Smart Distribution Grid

Smart distribution network will achieve the optimal operation of the distribution network, provide high-quality and reliable power, guarantee the development of modern social economy. The deep integration of cyber system and power physical system is the key to smart distribution network. The emergence of cyber-physical system (CPS) provides a new way to solve this problem, the cyber-physical model for smart distribution grid becomes an urgent problem to be solved. In this paper, the content and method of cyber-physical model for smart distribution grid are analyzed by combining with the coupling of information flow and power flow of smart distribution network from the perspective of cyber-physical model. At last, taking 110 kV typical substation as an example, the coupling mechanism and function of power flow and information flow is studied.

Discussion on the rationality of the “test status” of the smart protection devices

Starting from the concept of“test status”of conventional substations,this paper analyzes the existing“test status”of smart substations,and points out that it is unreasonable,then suggests to modify it to“inspection status”.

基于DBSCAN的智能变电站交流采样异常实时识别算法

新一代智能变电站使用采集执行单元统一采样,后续设备都将依赖此装置数据,因此该装置采样环节产生的异常数据会影响变电站保护、测控等多个系统的正常运行。如何高效地识别这些异常数据是电力系统采样中至关重要的部分,也是智能变电站安全性和稳定性的基础。传统的异常数据检测方法主要设计用于处理低采样率场景下偶尔出现的异常采样点。随着智能变电站采样率的提高和电磁干扰问题的加剧,采样时连续多个采样点同时异常成为普遍现象。这使得原有识别算法准确率降低,而未被识别的异常数据可能会造成后续测控装置精度降低甚至保护装置误动。针对传统检测方法的不足,提出基于密度的噪声空间聚类(density-based spatial clustering of applications with noise,DBSCAN)算法的交流采样异常数据识别实时算法。该算法利用异常数据与正常数据的空间密度差异,有效区分出密度较低的异常采样点,从而实现智能变电站异常采样数据的识别。相比于传统方法,所提方法在采样异常数据识别上具有更准确的结果。

云调控与变电站设备监测技术融合应用研究

针对变电站设备仿真以及监测系统,结合云技术,展开了云调控与变电站设备监测技术融合应用研究,为智能变电站提供了能量管理和设备管理,实现了对系统有功、无功功率的实时监测,同时也能满足北京电力公司职业技能培训的要求。

基于GOOSE反馈机制的智能变电站过程层网络备用方法

智能变电站过程层光纤网络一旦发生故障,会使二次系统功能失效,故障修复效率低,可靠性降低。为此,提出一种基于GOOSE反馈机制的智能变电站过程层网络备用方法。文章根据二次系统对过程层网络的传输要求,对间隔抖动、丢帧率和光功率等指标建立相应的危害程度量化模型;建立了备用光纤光口单指标和综合指标启动判据;利用GOOSE反馈机制实现对主光纤光口的备用。仿真表明,所提方法可快速完成故障光纤光口的备用切换,提高了过程层网络的可靠性。

基于电子式电压互感器边界特性分析的35 kV配网输电线路单端暂态量保护方案及其整定

随着分布式电源广泛接入配电网,传统三段式电流保护方案的性能严重劣化。单端暂态量边界保护由于具备不依赖电源特性等突出优势,有望成为改善主动配电网保护配置性能的有效方案,但其需依附于线路边界强健的滤波作用。为此,该文研究发现,可利用智能变电站和智能开闭所中电子式电压互感器、金属氧化物避雷器与其余设备杂散电容共同作为线路边界,其优异的高频滤波作用能够为暂态量保护方案的设计奠定基础;其次,利用区内外故障时电压行波高频频带能量差异构造保护判据,并基于整定门槛与动作时序的合理配合形成单端暂态量阶段式保护方案;最后,基于PSCAD仿真平台验证所提方案的有效性、灵敏性与可靠性,其可与电流保护方案协同互济以强化主动配电网继电保护方案的动作性能。

基于连接状态定位的智能变电站二次系统故障定位方法

变电站二次回路及系统运行状态因设备自身及物理连接等原因具有一定的不确定性,二次系统故障定位难度较大。提出一种基于连接状态定位的智能变电站二次系统故障定位方法。首先将二次系统设备拓扑连接关系抽象为矩阵描述,二次系统设备节点状态量作为相应矩阵元素;然后通过矩阵算法对二次系统连接状态进行定位,确定与故障有关的矩阵元素;在连接状态定位后利用模糊径向基神经网络将故障相关矩阵元素与故障集中各故障情况对应,进行故障搜索定位。故障算例结果表明,所提出的二次系统故障定位方法具有较高的准确率。

基于自编码器与时域卷积神经网络算法的配电网线损分析

复杂的配电网环境中存在线损计算精确性、实时性不足的问题,因此提出基于循环神经网络自编码器改进的TCN-BiGRU配电网线损预测方法。选用擅长处理时间序列的TCN神经网络模型作为主干特征提取网络,在TCN中融入BiGRU单元以有效解决梯度消失问题。在此基础上,结合循环神经网络自编码器对线损异常值进行无监督分类并标记,通过softmax损失函数预测线损率异常原因,并制定相应降损措施,同时利用改进后的TCN-BiGRU算法对线损进行预测及成因分析。实验结果表明,与传统的配电网线损预测方法相比,该线损预测方法的均方根误差相较于传统的EMD-LSTM与PSO-CNN算法分别降低了0.03699和0.00402,在线损成因分析方面的准确率相较于ResNet50与DBN-DNN算法分别提高了1.500%和5.841%,为分布式电源接入后配电网节能降损、实现电网双碳目标提供了科学的参考依据。

智能变电站二次装置一键式隔离系统研究

由于通信机制虚拟化及网络化,智能变电站二次回路检修时难以对二次回路进行经济有效隔离。文中建立了智能变电站二次装置一键式隔离系统,并给出系统需要的软件和硬件配置方案。首先介绍了研究理论方法,利用无提取的可扩展标记语言解析方法对智能变电站IEC 61850 SCD配置文件进行快速解耦和分析计算,并把站内检修与改扩建过程中的隔离范围问题转化为图信号处理方法中的事件扩散问题,并通过图信号处理技术实现复杂数据处理算法可视化展示。然后给出了SV链路、GOOSE输出链路、GOOSE接收链路和软压板之间的对应规则,明确检修时隔离的范围。最后,对装置隔离的安全措施序列可视化生成,能够直观地显示二次回路的隔离情况,协助现场人员进行检修工作。

基于改进Bi-LSTM的虚回路自动校验方法研究

针对智能变电站中虚回路人工校验效率低下、依赖于变电站配置描述(Substation configuration description,SCD)文件中虚端子定义不规范等问题,提出一种基于改进双向长短时记忆网络(Bi-directional long short-term memory,Bi-LSTM)的虚回路自动校验方法。首先,利用Word2vec模型对虚端子描述文本进行向量化编码,解决了虚端子描述文本的非结构化问题,使其能够在后续处理中被有效识别和分析。然后,引入了注意力机制与Bi-LSTM网络相结合的方式,以更全面地提取虚端子描述文本的语义特征。通过对比非标准虚端子与标准虚端子之间的相似度,实现了非标准虚端子的智能匹配,并建立了一个标准虚端子库作为基础数据支持。接着,利用经过验证的SCD文件与标准虚端子库,构建了虚回路模板库,该模板库能够有效存储并管理各类智能变电站设备的虚回路信息。最终,基于虚回路模板库实现了虚回路的自动校验,显著提升了虚回路校验过程的效率和准确性。试验结果表明,所提方法不仅提升了智能变电站虚回路校验的自适应性和精确度,还能够有效降低人工校验的工作量,显著提高智能变电站的自动化运行水平。该研究为未来智能变电站的虚回路校验和管理提供了重要的技术参考。

智能变电站线路保护光纤纵差调试研究

光纤纵差保护是保护输电线路设备平稳运行的主要手段,智能变电站光纤纵差保护存在多种功能方式。通过对智能变电站线路保护中的光纤纵差保护各项功能调试方法进行探究与梳理,针对光纤纵差保护中工频变化量差动、稳态I段和II段相差动、零序电流差动以及CT断线时的差动保护等提出了详实、易操作的调试方案,满足了站内作业人员对于智能变电站线路保护装置中光纤纵差保护的调试需求,缩短了智能变电站线路保护的调试时间。

基于威胁情报语义规则抽取的智能变电站告警分析方法

威胁情报作为一种弥补攻防信息不对称的安全技术,能够帮助安防人员发现威胁行为,并采取相应的预防措施。近年来,威胁情报研究受到业界广泛关注,然而现有的研究对威胁情报的利用率较低,为此,提出了一种基于威胁情报语义规则抽取的智能变电站告警分析方法。首先,通过构建语义规则模型生成语义规则图,对攻击技术手段进行描述;其次,面向ATT&CK攻击技术文本构建语义规则抽取框架,对攻击技术文本进行知识抽取,从中得到语义规则。该方法在解决智能变电站告警信息冗余繁杂问题的同时,提升了威胁情报的利用率,实现了对高层级威胁情报的自动化分析与处理。