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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Intrusion Detection and Recovery of a Cyber-Power System

Zhu, Ruoxi 06 June 2024 (has links)
The advent of Information and Communications Technology (ICT) in power systems has revolutionized the monitoring, operation, and control mechanisms through advanced control and communication functions. However, this integration significantly elevates the vulnerability of modern power systems to cyber intrusions, posing severe risks to the integrity and reliability of the power grid. This dissertation presents the results of a comprehensive study into the detection of cyber intrusions and restoration of cyber-power systems post-attack with a focus on IEC 61850 based substations and recovery methodologies in the cyber-physical system framework. The first step of this study is to develop a novel Intrusion Detection System (IDS) specifically designed for deployment in automated substations. The proposed IDS effectively identifies falsified measurements within Manufacturing Messaging Specification (MMS) messages by verifying the consistency of electric circuit laws. This distributed approach helps avoid the transfer of contaminated measurements from substations to the control center, ensuring the integrity of SCADA systems. Utilizing a cyber-physical system testbed and the IEEE 39-bus test system, the IDS demonstrates high detection accuracy and validates its efficacy in real-time operational environments. Building upon the intrusion detection methodology, this dissertation advances into cyber system recovery strategies, which are designed to meet the challenges of restoring a power grid as a cyber-physical system following catastrophic cyberattacks. A novel restoration strategy is proposed, emphasizing the self-recovery of a substation automation system (SAS) within the substation through dynamic network reconfiguration and collaborative efforts among Intelligent Electronic Devices (IEDs). This strategy, validated through a cyber-power system testbed incorporating SDN technology and IEC 61850 protocol, highlights the critical role of cyber recovery in maintaining grid resilience. Further, this research extends its methodology to include a cyber-physical system restoration strategy that integrates an optimization-based multi-system restoration approach with cyber-power system simulation for constraint checking. This innovative strategy developed and validated using an Software Defined Networking (SDN) network for the IEEE 39-bus system, demonstrates the capability to efficiently restore the cyber-power system and maximize restoration capability following a large-scale cyberattack. Overall, this dissertation makes original contributions to the field of power system security by developing and validating effective mechanisms for the detection of and recovery from cyber intrusions in the cyber-power system. Here are the main contributions of this dissertation: 1) This work develops a distributed IDS, specifically designed for the substation automation environment, capable of pinpointing the targets of cyberattacks, including sophisticated attacks involving multiple substations. The effectiveness of this IDS in a real-time operational context is validated to demonstrate its efficiency and potential for widespread deployment. 2) A novel recovery strategy is proposed to restore the critical functions of substations following cyberattacks. This strategy emphasizes local recovery procedures that leverage the collaboration of devices within the substation network, circumventing the need for external control during the initial recovery phase. The implementation and validation of this method through a cyber-physical system testbed—specifically, within an IEC 61850 based Substation Automation System (SAS)—underscores its practicality and effectiveness in real-world scenarios. 3) The dissertation results in a new co-restoration strategy that integrates mixed integer linear programming to sequentially optimize the restoration of generators, power components, and communication nodes. This approach ensures optimal restoration decisions within a limited time horizon, enhancing the recovery capabilities of the cyber-power system. The application of an SDN based network simulator facilitates accurate modeling of cyber-power system interactions, including communication constraints and dynamic restoration scenarios. The strategy's adaptability is further improved by real-time assessment of the feasibility of the restoration sequence incorporating power flow and communication network constraints to ensure an effective recovery process. / Doctor of Philosophy / Electricity is a critical service that supports the society and economy. Today, electric power systems are becoming smarter, using advanced Information and Communications Technology to manage and distribute electricity more efficiently. This new technology creates a smart grid, a network that not only delivers power but also uses computers and other tools to remotely monitor electricity flows and address any issues that may arise. However, these smart systems with high connectivity utilizing information and communication systems can be vulnerable to cyberattacks, which could disrupt the electricity supply. To protect against these threats, this study is focused on creating systems that can detect when an abnormal condition is taking place in the cyber-power grid. These detection systems are designed to detect and identify signs of cyberattacks at key points in the power network, particularly at substations, which play a vital role in the delivery of electricity. Substations control the power grid operating conditions to make sure that electricity service is reliable and efficient for the consumers Just like traffic lights help manage the flow of vehicles, substations manage the flow of electricity to make sure electric energy is delivered to where it needed. Once a cyberattack is detected, the next step is to stop the attack and mitigate the impact it may have made to ensure that the power grid returns to normal operations as quickly as possible. This dissertation is concerned with the development and validation of analytical and computational methods to quickly identify the cyberattacks and prevent the disruptions to the electricity service. Also, the focus of this work is also on a coordinated recovery of both the cyber system ( digital controls and monitoring) and power system (physical infrastructure including transformers and transmission and distribution lines). This co-restoration approach is key to sustain the critical electricity service and ensures that the grid is resilient against the cyber threats. By developing strategies that address both the cyber and physical aspects, the proposed methodology aims to minimize downtime and reduce the impact of large-scale cyberattacks on the electrical infrastructure. The impact of the results of this dissertation is the enhancement of security and resilience of the electric energy supply in an era where the risks of cyber threats are increasingly significantly. Overall, by developing new methodologies to detect and respond to cyberattacks, the cyber-power system's capability to withstand and recover from cyberattacks is enhanced in the increasingly technology-dependent power grid environment.
62

Automatización de una Subestación Eléctrica utilizando el Protocolo IEC 61850 y el ICCP para el envio de Datos

Toscano Palacios, Marco Antonio January 2010 (has links)
This thesis report, focuses on the automation process of Electrical Substations, with the main objective of integration into SCADA systems for electrical equipment responsible for the operation within substations, these devices have different communication protocols, after concentration information substation SCADA system, the next step to realize is sending data to the regulatory body that is in a remote location away from the substation, this is achieved using communication protocols designed for this function. All this process requires an optimization for the response times to any event that may happen in the substations and with this an optimization in operation of generation, distribution and transformation of electrical energy
63

Unidade eletrônica microprocessada para tratamento de sinais de transformadores de instrumentação ópticos e convencionais para aplicações metrológicas in situ. / Microprocesse electronic unit for signal treatment from optical and conventional instrument transformersmfor on-site metrological applications.

Nagao Junior, Shigueru 27 January 2017 (has links)
As elevadas perdas existentes no setor elétrico tem causado preocupação nas empresas de distribuição, aliadas ainda a necessidade crescente de um desenvolvimento econômico sustentável. Neste cenário a calibração periódica dos instrumentos destinados a medição (entre eles os transformadores de instrumentos) tornam-se essenciais e tais procedimentos encontram-se previstos no novo modelo de operação do setor elétrico. Porém, as dificuldades logísticas e operacionais de transporte a laboratórios metrológicos credenciados dificultam a execução de tais serviços. As técnicas e métodos desenvolvidos nesse trabalho visam a implementação de uma unidade eletrônica capaz de aquisitar e processar dados provenientes de transformadores de instrumentos, de natureza indutiva (denominado de convencional) e ópticos, bem como seus subsistemas de apoio, como ferramentas de medição e calibração portátil, móvel, para execução dos serviços metrológicos in situ nos ambientes das subestações e cabines primárias. Estes serviços, apesar de estarem em estágio incipiente, são de extremo interesse para empresas de energia elétrica. Este projeto está baseado no estado da arte de componentes da eletrônica analógica e digital, onde destacam-se conversores analógico/digital (A/D), microprocessadores, osciladores, FPGA e técnicas computacionais para processamento digital de sinais. São apresentadas as formas de implementação tanto em hardware como em software para esta unidade eletrônica de forma a atender aos requisitos funcionais especificados e às normas do INMETRO e normas internacionais equivalentes para aplicações metrológicas. A validação é baseada em testes comparativos dos fasores na frequência fundamental dos sinais obtidos, analisando os valores de amplitude (para cálculo de erro de relação) e de fase ( para cálculo de erro de fase) entre transformadores ópticos e convencionais, sendo que estes últimos podem ser de referência ou não. / The high losses in the electricity sector have caused concern in distribution companies, together with the growing need for sustainable economic development. In this scenario the periodic calibration of instruments intended for measurement (including instrument transformers) become essential and such procedures are provided for in the new model of operation of the electric sector. However, the logistical and operational difficulties of transportation to accredited metrological laboratories make it difficult to perform such services. The techniques and methods developed in this work are aimed at the implementation of an electronic unit capable of acquiring and processing data from instrument transformers of an inductive (conventional) and optical nature, as well as its supporting subsystems, such as portable and mobile measuring and calibration tools for the execution of on-site metrological services in the substations and primary cabins. These services, although in an incipient stage, are of extreme interest to electric energy companies. This project is based on the state-of-the-art components of analog and digital electronics, including analog/digital (A/D) converters, microprocessors, oscillators, FPGA and computational techniques for digital signal processing. The forms of implementation in both hardware and software for this electronic unit are presented in order to meet the functional requirements specified and the standards of the Instituto Nacional de Metrologia (INMETRO) and equivalent international standards for metrological applications. The validation is based on comparative tests of the phasors at the fundamental frequency of the obtained signals, analyzing the amplitude (for ratio error calculation) and phase (for phase error calculation) between optical and conventional transformers, the last one can be reference or not.
64

Unidade eletrônica microprocessada para tratamento de sinais de transformadores de instrumentação ópticos e convencionais para aplicações metrológicas in situ. / Microprocesse electronic unit for signal treatment from optical and conventional instrument transformersmfor on-site metrological applications.

Shigueru Nagao Junior 27 January 2017 (has links)
As elevadas perdas existentes no setor elétrico tem causado preocupação nas empresas de distribuição, aliadas ainda a necessidade crescente de um desenvolvimento econômico sustentável. Neste cenário a calibração periódica dos instrumentos destinados a medição (entre eles os transformadores de instrumentos) tornam-se essenciais e tais procedimentos encontram-se previstos no novo modelo de operação do setor elétrico. Porém, as dificuldades logísticas e operacionais de transporte a laboratórios metrológicos credenciados dificultam a execução de tais serviços. As técnicas e métodos desenvolvidos nesse trabalho visam a implementação de uma unidade eletrônica capaz de aquisitar e processar dados provenientes de transformadores de instrumentos, de natureza indutiva (denominado de convencional) e ópticos, bem como seus subsistemas de apoio, como ferramentas de medição e calibração portátil, móvel, para execução dos serviços metrológicos in situ nos ambientes das subestações e cabines primárias. Estes serviços, apesar de estarem em estágio incipiente, são de extremo interesse para empresas de energia elétrica. Este projeto está baseado no estado da arte de componentes da eletrônica analógica e digital, onde destacam-se conversores analógico/digital (A/D), microprocessadores, osciladores, FPGA e técnicas computacionais para processamento digital de sinais. São apresentadas as formas de implementação tanto em hardware como em software para esta unidade eletrônica de forma a atender aos requisitos funcionais especificados e às normas do INMETRO e normas internacionais equivalentes para aplicações metrológicas. A validação é baseada em testes comparativos dos fasores na frequência fundamental dos sinais obtidos, analisando os valores de amplitude (para cálculo de erro de relação) e de fase ( para cálculo de erro de fase) entre transformadores ópticos e convencionais, sendo que estes últimos podem ser de referência ou não. / The high losses in the electricity sector have caused concern in distribution companies, together with the growing need for sustainable economic development. In this scenario the periodic calibration of instruments intended for measurement (including instrument transformers) become essential and such procedures are provided for in the new model of operation of the electric sector. However, the logistical and operational difficulties of transportation to accredited metrological laboratories make it difficult to perform such services. The techniques and methods developed in this work are aimed at the implementation of an electronic unit capable of acquiring and processing data from instrument transformers of an inductive (conventional) and optical nature, as well as its supporting subsystems, such as portable and mobile measuring and calibration tools for the execution of on-site metrological services in the substations and primary cabins. These services, although in an incipient stage, are of extreme interest to electric energy companies. This project is based on the state-of-the-art components of analog and digital electronics, including analog/digital (A/D) converters, microprocessors, oscillators, FPGA and computational techniques for digital signal processing. The forms of implementation in both hardware and software for this electronic unit are presented in order to meet the functional requirements specified and the standards of the Instituto Nacional de Metrologia (INMETRO) and equivalent international standards for metrological applications. The validation is based on comparative tests of the phasors at the fundamental frequency of the obtained signals, analyzing the amplitude (for ratio error calculation) and phase (for phase error calculation) between optical and conventional transformers, the last one can be reference or not.
65

Development of a laboratory facility and experiments to support learning IEC 61850 based substation automation

Wickremasuriya, Boosabaduge Achintha Hiruwan 08 January 2016 (has links)
IEC 61850 is rapidly becoming the internationally recognized standard for substation automation systems making it an indispensable element in power system protection and automation education. In order to facilitate teaching this very practical subject, a laboratory setup was developed to demonstrate IEC 61850 station bus inter Intelligent Electronic Device (IED) communication. In this setup, an electrical substation was implemented in a real time digital simulator (RTDS) and protection schemes were implemented in IEC 61850 station bus compliant IEDs from different vendors. Trip signals and breaker statuses were exchanged between RTDS and IEDs using GOOSE (Generic Object Oriented Substation Event) messages. Several protection applications including a novel backup bus protection scheme were developed based on the setup to demonstrate the use of GOOSE messages in time critical applications. The developed test setup along with the designed laboratory exercises will undoubtedly enhance teaching, training and research in this important field. / February 2016
66

State-of-the-art development platform for hydropower turbine governors

Näsström, Joakim January 2017 (has links)
Hydropower is a flexible energy source that is essential for balancing the electrical power system on all timescales, from seconds to years. In addition to intra-hour regulation, it provides frequency containment reserves (FCR-N,FCR-D) and frequency restoration reserves (mFRR, aFRR) to the grid. The turbine governor is a device responsible for controlling the power output and delivering frequency control to the system. The aim of this Master’s Thesis project is to develop a new hydropower turbine governor in MATLAB/Simulink, which contains all critical functionality from the existing governor and with the same performance. The new governor should as far as possible comply to the well-established communication standard IEC 61850. A working model of the turbine governor has been built in Simulink that supports normal operation with frequency control, start and stop, load rejection, operation mode as synchronous condenser and more. Validations of the model against data from Akkats powerplant shows that the model behaves as a real governor during normal operation. Validations of the start sequence showed deviations during sequence 3 and 4 which can be explained by usage of different PID parameters. Using IEC 61850 as a nomenclature and as a way of structuring functions in the governor has also been possible. Implementing the whole standard for communication, requires that the control system also is renewed according to IEC 61850. Certain functions, as sequencing has thus not been done according to the standard. MATLAB and Simulink provide tools for building, simulating and testing implementations of the turbine governor. The contributions this platform can provide are; ease of implementation, optimization and testing of control strategies. Simulink also provides a graphical interface, which reduce system complexity. An optimal implementation requires a hardware with support for Simulink to get a transparent platform. Ultimately, these benefits could result in better frequency quality at a lower cost, which is essential for successful and cost-effective integration of other renewable energy sources such as wind- and solar power.
67

Identifikace dostupnosti zařízení v technologických sítích / Identification of Device Availability in Technological Networks

Vodehnal, Stanislav January 2018 (has links)
This diploma thesis deals with the monitoring of network elements of technological networks and distribution systems. There are described reasons why and what kind of values we want to monitor. Three monitoring systems are then selected, described their properties and functions. Based on their merits, one system for deploying the test environment is selected. The practical part is the configuration of the selected system and its subsequent deployment to the network.
68

Testování zranitelností v průmyslových sítích / Vulnerabilities assessment for industrial protocols

Zahradník, Jiří January 2020 (has links)
Thesis deals with testing of selected vulnerabilities from the IEC 61850 standard and following design of mitigation measures for selected vulnerabilities. Author simulated vulnerabilities of the GOOSE protocol, NTP attack and attack ona MMS client. Those attacks were GOOSE stNum, GOOSE semantic, GOOSE test bit,GOOSE replay, GOOSE flood, NTP spoofing and MMS password capture. Attacks on protocols GOOSE and MMS were successful, attack on NTP was only partially successful since the device confirmed receiving spoofed time, however it did not change it’s inner clock. Author then designed possible mitigation measures. Tool for automatic testing of selected vulnerabilities, parser for the GOOSE protocol and lightweight multiplatform parser for configuration files were created as well.The outcome of this thesis allows the implementation of lager scale tool for penetration testing of industrial networks as well as it allows implementation of discussed mitigation measures.
69

Otestovaní komunikace po IEC61850 s využitím GOOSE mezi ABB a Siemens ochranou / Testing Communication via IEC 61850 and GOOSE between ABB and Siemens Protections

Vavreczky, Gábor January 2012 (has links)
The main objective of this thesis is to examine the possibility of cooperation of IEDs from ABB and Siemens in accordance with IEC61850. The aim is to create and test a workflow, after which protection relays from ABB and Siemens will communicate with each other via GOOSE messages. This paper provides a description of the international standard IEC61850, as a theoretical basis. Describes in detail the configuration of protection relays SIPROTEC 7SA610 according to IEC61850. Work provides a description of the configuration tools PCM600 and IET600 which are used for configuration of protection relays RELION® REF615 by ABB. In the final part of the work experiences that are written in collaboration used protection.
70

Automatizace rozvodny VN s využitím řídicího systému COM600 a standardu IEC61850 / Medium voltage substation automation using control system COM600 and standard IEC61850

Havelka, Tomáš January 2016 (has links)
This work deals with problematic of standard IEC61850, mainly with chapter IEC 61850-9-2 LE which is commonly known as Process bus communication. There are described advanced tools of the control system COM600 with detail description of their configuration in this work. It also deals with configuration of IEC 61850-9-2 LE with Relion family protection relays and its implementation to the control system COM600. The main aim of this work is focused on configuration of IEC 61850-9-2 standard with protection relays, configuration and detail description of COM600 advanced tools, description of Logic processor, further custom design and appliaction configuration global reset of Logic procesor in control system COM600.

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