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101.
IEC 61850, an international standard for communication networks, is becoming prevalent in the cyber–physical system (CPS) environment, especially with regard to the electrical grid. Recently, since cyber threats in the CPS environment have increased, security matters for individual protocols used in this environment are being discussed at length. However, there have not been many studies on the types of new security vulnerabilities and the security requirements that are required in a heterogeneous protocol environment based on IEC 61850. In this paper, we examine the electrical grid in Korea, and discuss security vulnerabilities, security requirements, and security architectures in such an environment. 相似文献
102.
This paper presents a methodology for the testing of intelligent electronic devices (IEDs) in IEC 61850-based substation automation systems (SAS), without any service interruption to the end users, during the testing process. IEC 61850-based SAS provides opportunities for a new level of substation operation, enhancing operating efficiency, and protection reliability based on Ethernet-based communication networks. Due to these changes to the conventional substations, importance and dependency on IEDs is increasing rapidly. Frequency of faults occurring in the power systems is random in nature and is unpredictable. It is necessary to test and maintain the IEDs to ensure their proper operation at crucial times. This paper presents a novel methodology for testing the IEDs, without compromising the service reliability during the testing process. The proposed methodology exploits the inherit characteristics of IEC 61850 standard i.e. Network - based communication, interchangeability between multivendor IEDs, and engineering based on substation configuration language (SCL) files. The feasibility and robustness of the proposed method has been verified by performing several performance verification tests with different performance metrics. 相似文献
103.
《Measurement》2014
This paper proposes a new technique for estimating phasors during the transient phenomena in the electrical power systems. Unlike traditional Phasor Measurement Units (PMUs) that estimates phasors at process level, the proposed technique estimates phasors at bay level. The estimation technique relies on a robust recursive Kalman–Filtering, which is employed for computing the phasors based on the time-critical IEC 61850-9-2 Sampled Measured Values casted by the substation Merging Units (MUs). Many evolution tests of the proposed technique have been carried out for both stationary and transient phenomena in power systems to determine the accuracy of the measurements obtained at various conditions. The proposed estimator can produce phasors at bay level with reporting rate of 100 frames per second, which is encouraged in IEEE Std C37.118 and can satisfy higher accuracies than provided by the traditional Phasor Measurement Units, which are 0.01 degree and 0.01% for phase and magnitude, respectively. 相似文献
105.
IEC 61850信息模型一致性校验的核心问题是如何对模型信息的规则进行表达。通过对SCL Schema的分析后发现,Schema表达了SCL语言要素的基本语法结构,受限于Schema语言的特点,对不同语法层次上的信息间的约束表达较弱,无法用其来完整地表达IEC 61850模型规则。通过引入Schematron语言,分析其对SCL信息规则表达的规律,实现了IEC 61850模型信息的复杂约束条件的表达,提出将SCL Schema表达与Schematron语言的表达结合起来,对IEC 61850信息模型的规 相似文献
106.
为提高配网自动化资产管理水平,针对配网成套开关,研制出一种基于IEC 61850的状态监测系统。系统由就地传感器网络、状态监测IED(智能电子设备Intelligent Electronic Device,以下简称IED)、状态监测诊断系统组成,对配电成套开关设备的机械特性、热特性、绝缘特性进行监测、分析和诊断。状态监测系统遵循IEC 61850第二版状态监测逻辑节点建模,对内、对外通信采用IEC 61850标准通信服务,做到与配网自动化系统无缝结合,可与配电自动化终端(Distribution Terminal Unit,DTU)、配网自动化信息互动。实际工程应用效果表明,监测系统是有效和实用的,可对配网设备提出维护建议,极大减轻维护人员的负担,为配网馈线自动化、自愈功能提供一次设备状态信息,从而加快智能配电网建设。 相似文献
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