Impact Assessment of Hypothesized Cyberattacks on Interconnected Bulk Power Systems

The first-ever Ukraine cyberattack on power grid has proven its devastation by hacking into their critical cyber assets. With administrative privileges accessing substation networks/local control centers, one intelligent way of coordinated cyberattacks is to execute a series of disruptive switching executions on multiple substations using compromised supervisory control and data acquisition (SCADA) systems. These actions can cause significant impacts to an interconnected power grid. Unlike the previous power blackouts, such high-impact initiating events can aggravate operating conditions, initiating instability that may lead to system-wide cascading failure. A systemic evaluation of "nightmare" scenarios is highly desirable for asset owners to manage and prioritize the maintenance and investment in protecting their cyberinfrastructure. This survey paper is a conceptual expansion of real-time monitoring, anomaly detection, impact analyses, and mitigation (RAIM) framework that emphasizes on the resulting impacts, both on steady-state and dynamic aspects of power system stability. Hypothetically, we associate the combinatorial analyses of steady state on substations/components outages and dynamics of the sequential switching orders as part of the permutation. The expanded framework includes (1) critical/noncritical combination verification, (2) cascade confirmation, and (3) combination re-evaluation. This paper ends with a discussion of the open issues for metrics and future design pertaining the impact quantification of cyber-related contingencies

EXTRACTION OF PICTORIAL ENERGY INFORMATION FROM CAMPUS UNMETERED BUILDINGS USING IMAGE PROCESSING TECHNIQUES

In recent years, advanced metering infrastructure (AMI) has been the main research focus due to the traditional power grid has been restricted to meet development requirements. There has been an ongoing effort to increase the number of AMI devices that provide real-time data readings to improve system observability. Deployed AMI across distribution secondary networks provides load and consumption information for individual households which can improve grid management. Significant upgrade costs associated with retrofitting existing meters with network-capable sensing can be made more economical by using image processing methods to extract usage information from images of the existing meters. This thesis presents a new solution that uses online data exchange of power consumption information to a cloud server without modifying the existing electromechanical analog meters. In this framework, application of a systematic approach to extract energy data from images replaces the manual reading process. One case study illustrates the digital imaging approach is compared to the averages determined by visual readings over a one-month period

Enabling sustainable power distribution networks by using smart grid communications

Smart grid modernization enables integration of computing, information and communications capabilities into the legacy electric power grid system, especially the low voltage distribution networks where various consumers are located. The evolutionary paradigm has initiated worldwide deployment of an enormous number of smart meters as well as renewable energy sources at end-user levels. The future distribution networks as part of advanced metering infrastructure (AMI) will involve decentralized power control operations under associated smart grid communications networks. This dissertation addresses three potential problems anticipated in the future distribution networks of smart grid: 1) local power congestion due to power surpluses produced by PV solar units in a neighborhood that demands disconnection/reconnection mechanisms to alleviate power overflow, 2) power balance associated with renewable energy utilization as well as data traffic across a multi-layered distribution network that requires decentralized designs to facilitate power control as well as communications, and 3) a breach of data integrity attributed to a typical false data injection attack in a smart metering network that calls for a hybrid intrusion detection system to detect anomalous/malicious activities. In the first problem, a model for the disconnection process via smart metering communications between smart meters and the utility control center is proposed. By modeling the power surplus congestion issue as a knapsack problem, greedy solutions for solving such problem are proposed. Simulation results and analysis show that computation time and data traffic under a disconnection stage in the network can be reduced. In the second problem, autonomous distribution networks are designed that take scalability into account by dividing the legacy distribution network into a set of subnetworks. A power-control method is proposed to tackle the power flow and power balance issues. Meanwhile, an overlay multi-tier communications infrastructure for the underlying power network is proposed to analyze the traffic of data information and control messages required for the associated power flow operations. Simulation results and analysis show that utilization of renewable energy production can be improved, and at the same time data traffic reduction under decentralized operations can be achieved as compared to legacy centralized management. In the third problem, an attack model is proposed that aims to minimize the number of compromised meters subject to the equality of an aggregated power load in order to bypass detection under the conventionally radial tree-like distribution network. A hybrid anomaly detection framework is developed, which incorporates the proposed grid sensor placement algorithm with the observability attribute. Simulation results and analysis show that the network observability as well as detection accuracy can be improved by utilizing grid-placed sensors. Conclusively, a number of future works have also been identified to furthering the associated problems and proposed solutions

Mikroverkkojen ja hajautettujen energiaratkaisujen suojaus IEC 61850 -standardiin perustuen

Microgrids are a potential part of the future smart distribution grid with capability of island operation, envisioned to support the goals of increased use of renewable and distributed energy resources, active consumer participation and improved quality of electricity supply in the future power systems. This thesis examines the implementation of protection systems for microgrids and distributed energy resources using the IEC 61850 standard series. IEC 61850 is one of the core smart grid standards originally developed for substation automation, but extended in its usage to many areas including distributed energy resources. The main objectives of this thesis are analysing the implementation of microgrid protection, usage of IEC 61850 in distribution applications, and applicability of Multipower test environment of VTT Technical Research Centre of Finland in researching these subjects. A literature review of microgrid protection issues and proposed protection schemes as well as an overview of the IEC 61850 standard series and its extensions are presented. An adaptive protection scheme is implemented in an example microgrid configuration of the Multipower environment using IEC 61850, and its correct operation verified during islanding and in the case of a communication network failure. Finally, recommendations are given on the future development and research topics of the Multipower environment, including integration of different distributed energy resource units from other VTT research areas such as fuel cells and electrical vehicles to the system, studying the usage of different networks for communication inside the environment and testing of harmonization between IEC 61850 and other smart grid standards

IoT-teknologian hyödyntäminen sähköverkko-omaisuuden hallinnassa

Objective of this thesis is to define and assess changes in energy sector, which will directly or indirectly affect distribution grid operation and management in Finland, and to determine measurable events or variables, which enable identification and monitoring of the recognized changes. Based on assessment of the upcoming changes, possibilities for utilizing IoT technologies in management and monitoring applications of the identified changes, are assessed. In the assessment of upcoming changes, total of eight subjects were covered and microgeneration, electric vehicles and heat pumps were identified to be the most probable changes to realistically penetrate Finnish energy sector within a time scope of approximately 10 years. However, none of the assessed, changes, were found to have significant and wide-scale effects in terms of performance of Finnish distribution networks. For utilization of IoT technologies in distribution networks one application for operational grid monitoring of power quality problems derived from residential photovoltaic generation, and three cases for IoT based asset health and condition monitoring were assessed. Furthermore, requirements and architecture for data storage and analysis platform of IoT based system were discussed. From the evaluated applications condition monitoring scheme of circuit breakers was determined to be the most promising alternative.Diplomityön tavoitteena on määritellä ja arvioida energiasektoriin vaikuttavien tulevien muutosten suoria tai epäsuoria vaikutuksia jakeluverkon toimintaan ja hallintaan. Havaittujen muutosten vaikutuksista on tarkoitus tunnistaa mitattavia ilmiöitä tai suureita, jotka mahdollistavat muutosten tunnistamisen sekä seurannan. Muutosanalyysiin pohjautuen tavoitteena on tunnistaa ja arvioida mahdollisuuksia IoT-teknologian hyödyntämiseksi havaittujen muutosten aiheuttamien ongelmakohtien tai mahdollisuuksien tunnistamisessa, seurannassa sekä hallinnassa. Energiasektoriin vaikuttavien muutosten analyysissä arvoitiin kokonaisuudessaan kahdeksaa eri aihealuetta ja lopputuloksena pientuotannon, sähköautojen sekä lämpöpumppujen todettiin olevan todennäköisimmät teknologiat, jotka yleistyvät merkittävissä määrin suomalaisessa sähköverkossa seuraavan kymmenen vuoden aikana. Minkään käsitellyn muutoskohdan ei kuitenkaan todettu aiheuttavan laajamittaisia ja merkittäviä ongelmia jakeluverkon toimintaan. IoT-teknologian hyödyntämiseen jakeluverkkotoiminnassa käsiteltiin yhtä verkon käyttöön ja sähkön laatuun liittyvää sovellusta, jonka avulla hajautetun pienaurinkotuotannon vaikutuksia pystytään seuraamaan, sekä lisäksi kolmeen eri verkkokomponenttiin kohdistuvaa jatkuvan kunnon seurannan sovellusta. Tämän lisäksi IoT-järjestelmän toteuttamiseksi vaadittavalle analyysi- ja tietojärjestelmäalustalle määriteltiin rakenteellisia ja toiminnallisia tarpeita. Työssä käsitellyistä IoT-sovelluksista lupaavimmaksi todettiin katkaisijoihin kohdistuva jatkuvan kunnonhallinnan sovellus

Parameter Identification of Micro-Grid Control System

Micro-grid provides an effective means of integrating distributed energy resource (DER) units into the power systems. A micro-grid is defined as an independent low- or medium-voltage distribution network comprising various DER units, power-electronic interfaces, controllable loads, and monitoring and protection devices. Following the development of the renewable energy, micro-grid has attracted much attention. This thesis emphasizes on the parameter identification of the control system of the micro-grid. The control system plays an important role in the stable operation of the micro-grid. The micro-grid has two operation modes, which are grid-connected operation mode and islanded operation mode. The transition between two operation modes of the micro-grid often occurs according to the condition of the entire grid. In order to make this process smooth, the control system is crucial, and the parameters of the control system is critical to the disturbance suppression during the process of transition. In the thesis, a method combining least square method with Newton-Raphson algorithm is proposed. In order to prove the utility of the method, the parameter identification of a typical control system and its several separated elements are simulated in MATLAB. This method can identify multiple parameters at the same time and have fast convergence

Security Monitoring of Distribution Automation Systems

Distribution automation systems represent the new generation of power distribution systems in response to the growing interest in smart grids along with the integration of information and communication technologies (ICT). Distribution automation systems leverage advanced ICTs to automate system operation for delivering electrical energy to consumers. With the use of ICT comes the need to protect distribution automation systems from cyberattacks that could impact the operation of such systems, mainly power availability. In this thesis, the main objective is to assess the security aspect of distribution automation systems. As such, we design and implement a security monitoring platform that allows assessing the dynamics of these systems. In this regard, a digital twin testbed is designed and implemented to simulate smart power distribution systems in near real-time. Moreover, a proposed security monitoring platform is designed and implemented on top of the previously mentioned digital twin testbed. The platform can help monitor the impacts of different occurring incidents and allows executing implemented cyberattacks against the modeled power systems. In addition, it employs AI techniques to detect these attacks. The specific contributions of this thesis are: (i) the design and implementation of a cosimulation testbed for distribution automation systems using open source software packages; (ii) the design and implementation of an AI-based security analytics framework for distribution automation systems; and (iii) the implementation of cyberattacks targeting distribution automation applications. Various machine and deep learning models are implemented to detect the attacks and different performance evaluation metrics are used to compare different models. The obtained results are competitive and they validate the usefulness of the models in detecting attacks. The co-simulation platform is able to simulate power distribution systems in near real-time, along with an emulation of the IEC 60870-5-104 communication protocol. Also, the platform is capable of simulating big distribution test cases, e.g., the IEEE 123-bus and the IEEE 8500-nodes systems. The proposed platform allows power utilities to assess the security of their power distribution systems without affecting power availability and quality

Multi-agent control and operation of electric power distribution systems

This dissertation presents operation and control strategies for electric power distribution systems containing distributed generators. First, models of microturbines and fuel cells are developed. These dynamic models are incorporated in a power system analysis package. Second, operation of these generators in a distribution system is addressed and load following schemes are designed. The penetration of distributed generators (DGs) into the power distribution system stability becomes an issue and so the control of those DGs becomes necessary. A decentralized control structure based on conventional controllers is designed for distributed generators using a new developed optimization technique called Guided Particle Swarm Optimization. However, the limitations of the conventional controllers do not satisfy the stability requirement of a power distribution system that has a high DG penetration level, which imposes the necessity of developing a new control structure able to overcome the limitations imposed by the fixed structure conventional controllers and limit the penetration of DGs in the overall transient stability of the distribution system. Third, a novel multi-agent based control architecture is proposed for transient stability enhancement for distribution systems with microturbines. The proposed control architecture is hierarchical with one supervisory global control agent and a distributed number of local control agents in the lower layer. Specifically, a central control center supervises and optimizes the overall process, while each microturbine is equipped with its own local control agent.;The control of naval shipboard electric power system is another application of distributed control with multi-agent based structure. In this proposal, the focus is to introduce the concept of multi-agent based control architecture to improve the stability of the shipboard power system during faulty conditions. The effectiveness of the proposed methods is illustrated using a 37-bus IEEE benchmark system and an all-electric naval ship