Substation Intelligent Electronic Devices Research Articles

Cyberattack Defense With Cyber-Physical Alert and Control Logic in Industrial Controllers

Power system substations have intelligent electronic devices (IEDs) that collect data and control other devices. As the bridge between the physical and cyber parts of the power system, IEDs capture some key system behaviors. Since adversaries can modify the system’s behavior, physical and cyber data can be used to infer characteristics about the adversary. In this article, we present alert and control logic for hardware-based power system defense using the physical data and communication status in substation IEDs for <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">cyber threat detection</i> , <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">cyber-physical contingency detection and response</i> , and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">physical contingency identification and response</i> . The proposed alert and control logic routines are implemented in an industrial real-time automation controller using IEC 61131-3 in the resilient energy systems lab testbed. The goal is to help operators identify adversaries and protect the power grid in a cyber-physical environment. The effectiveness and accuracy of logic schemes are validated under different adversarial scenarios. Comparing the proposed schemes with an intrusion detection system, Snort, our results also suggest the benefits of using cyber and physical data to identify threats. The results also suggest the use of such hardware-based schemes with software algorithms in a next-generation cyber-physical energy management system, which can implement automatic control actions to protect power grids and its physical equipment against cyber threats.

Reliability Evaluation of Power Grids Considering Integrity Attacks Against Substation Protective IEDs

Secure operation of protective intelligent electronic devices (IEDs) has been recognized as a crucial issue for power grids. By gaining access to substation IEDs, intruders can severely disrupt the operation of protection systems. This paper develops an analytical reliability assessment framework for quantifying the impacts of the hypothesized integrity attacks against protection systems. Petri net models are used to simulate possible intrusion scenarios into substation networks. The cyber network model is constructed from firewall, intrusion prevention system (IPS), and password models, which are three types of defense mechanisms for protecting substation networks. In this paper, two main types of attacker actions on protective devices are recognized: 1) sending breaker opening commands through IED connections; and 2) changing IED settings. In this regard, a multistate Markov model is proposed for identifying possible consequences of cyber attacks on the protective devices. In addition, this model captures the essential remedial actions that are taken after a successful cyber attack against target equipment. Subsequently, an analytical approach based on the introduced Markov model is proposed for assessing power system reliability. The proposed framework is implemented on the modified IEEE reliability test system, and its effectiveness is demonstrated through extensive case studies.

IEC 61850 SCL Validation Using UML Model in Modern Digital Substation

The IEC 61850 standard stipulates the Substation Configuration Description Language (SCL) file as a means to define the substation equipment, IED function and also the communication mechanism for the substation area network. The SCL is an eXtensible Markup Language (XML) based file which helps to describe the configuration of the substation Intelligent Electronic Devices (IED) including their associated functions. The SCL file is also configured to contain all IED capabilities including data model which is structured into objects for easy descriptive modeling. The effective functioning of this SCL file relies on appropriate validation techniques which check the data model for errors due to non-conformity to the IEC 61850 standard. In this research, we extend the conventional SCL validation algorithm to develop a more advanced validator which can validate the standard data model using the Unified Modeling Language (UML). By using the Rule-based SCL validation tool, we implement validation test cases for a more comprehensive understanding of the various validation functionalities. It can be observed from the algorithm and the various implemented test cases that the proposed validation tool can improve SCL information validation and also help automation engineers to comprehend the IEC 61850 substation system architecture.

Implementation requirements for automated fault data analytics in power systems

Summary This paper addresses implementation requirements for a fully automated substation data integration and fault analysis for power system transmission lines. The approach is based on measurements from substation intelligent electronic device recordings. The proposed architecture provides a transparent approach to substation data management, analytics functions, as well as the visualization of the integrated data and analytics results. When combined with an efficient communication and data collection scheme, the solution bridges the gap between traditionally separated non-operational and operational data. The fault analytics results, traditionally obtained through off-line manual process, can now be used in an automated way to support on-line decisions when operating or restoring the power system. The solution is open for further expansions and interfacing to third-party systems. The paper illustrates implementation examples and provides initial in-house and field test results. Copyright © 2014 John Wiley & Sons, Ltd.

The Modeling and Verification of Peer-to-Peer Negotiating Multiagent Colored Petri Nets for Wide-Area Backup Protection

This paper focuses on the modeling and verification of a peer-to-peer wide-area backup protection (WABP) system. Agents located in a number of substation intelligent electronic devices (IEDs) negotiate on a peer, or equal, basis. The agent-based wide-area backup protection scheme is able to find power-line faults and protection misoperations. A wide-area communication network based on IP technology is used to transmit shared information among the agents. A novel agent-oriented peer-to-peer negotiating colored Petri net (AOPCPN) is proposed to implement the WABP system. The algorithms, design, and dynamic behavior of the WABP is evaluated in a simulated environment to demonstrate its benefits. The article begins by presenting the generic AOPCPN architecture and its formal definition. The AOPCPN model for the WABP multiagent system is evaluated according to one algorithm, which is detailed in this article. The WABP agent's autonomy, cooperation, parallel operation, and robustness are embodied in modules in order to ease the software engineering challenges in implementing and maintaining the agents. Three example scenarios illustrate the effectiveness of the Petri net model and its ability to dynamically respond to WABP misoperations and fault conditions.