Cyber-Physical Power System (CPPS): A Review on Modelling, Simulation, and Analysis with Cyber Security Applications

Cyber-Physical System (CPS) is a new kind of digital technology that increases its attention across academia, government, and industry sectors and covers a wide range of applications like agriculture, energy, medical, transportation, etc. The traditional power systems with physical equipment as a core element are more integrated with information and communication technology, which evolves into the Cyber-Physical Power System (CPPS). The CPPS consists of a physical system tightly integrated with cyber systems (control, computing, and communication functions) and allows the two-way flows of electricity and information for enabling smart grid technologies. Even though the digital technologies monitoring and controlling the electric power grid more efficiently and reliably, the power grid is vulnerable to cybersecurity risk and involves the complex interdependency between cyber and physical systems. Analyzing and resolving the problems in CPPS needs the modelling methods and systematic investigation of a complex interaction between cyber and physical systems. The conventional way of modelling, simulation, and analysis involves the separation of physical domain and cyber domain, which is not suitable for the modern CPPS. Therefore, an integrated framework needed to analyze the practical scenario of the unification of physical and cyber systems. A comprehensive review of different modelling, simulation, and analysis methods and different types of cyber-attacks, cybersecurity measures for modern CPPS is explored in this paper. A review of different types of cyber-attack detection and mitigation control schemes for the practical power system is presented in this paper. The status of the research in CPPS around the world and a new path for recommendations and research directions for the researchers working in the CPPS are finally presented.publishedVersio

Cyber-Physical Systems: A Model-Based Approach

In this concise yet comprehensive Open Access textbook, future inventors are introduced to the key concepts of Cyber-Physical Systems (CPS). Using modeling as a way to develop deeper understanding of the computational and physical components of these systems, one can express new designs in a way that facilitates their simulation, visualization, and analysis. Concepts are introduced in a cross-disciplinary way. Leveraging hybrid (continuous/discrete) systems as a unifying framework and Acumen as a modeling environment, the book bridges the conceptual gap in modeling skills needed for physical systems on the one hand and computational systems on the other. In doing so, the book gives the reader the modeling and design skills they need to build smart, IT-enabled products. Starting with a look at various examples and characteristics of Cyber-Physical Systems, the book progresses to explain how the area brings together several previously distinct ones such as Embedded Systems, Control Theory, and Mechatronics. Featuring a simulation-based project that focuses on a robotics problem (how to design a robot that can play ping-pong) as a useful example of a CPS domain, Cyber-Physical Systems: A Model-Based Approach demonstrates the intimate coupling between cyber and physical components, and how designing robots reveals several non-trivial control problems, significant embedded and real-time computation requirements, and a need to consider issues of communication and preconceptions

A framework for analyzing and testing cyber-physical interactions for smart grid applications

The reliable performance of the smart grid is a function of the configuration and cyber- physical nature of its constituting sub-systems. Therefore, the ability to capture the interactions between its cyber and physical domains is necessary to understand the effect that each one has on the other. As such, the work in this paper presents a co-simulation platform that formalizes the understanding of cyber information flow and the dynamic behavior of physical systems, and captures the interactions between them in smart grid applications. Power system simulation software packages, embedded microcontrollers, and a real communication infrastructure are combined together to provide a cohesive smart grid cyber-physical platform. A data-centric communication scheme, with automatic network discovery, was selected to provide an interoperability layer between multi-vendor devices and software packages, and to bridge different protocols. The effectiveness of the proposed framework was verified in three case studies: (1) hierarchical control of electric vehicles charging in microgrids, (2) International Electrotechnical Committee (IEC) 61850 protocol emulation for protection of active distribution networks, and (3) resiliency enhancement against fake data injection attacks. The results showed that the cosimulation platform provided a high-fidelity design, analysis, and testing environment for cyber information flow and their effect on the physical operation of the smart grid, as they were experimentally verified, down to the packet, over a real communication network

Cyber-Physical Systems: A Model-Based Approach

In this concise yet comprehensive Open Access textbook, future inventors are introduced to the key concepts of Cyber-Physical Systems (CPS). Using modeling as a way to develop deeper understanding of the computational and physical components of these systems, one can express new designs in a way that facilitates their simulation, visualization, and analysis. Concepts are introduced in a cross-disciplinary way. Leveraging hybrid (continuous/discrete) systems as a unifying framework and Acumen as a modeling environment, the book bridges the conceptual gap in modeling skills needed for physical systems on the one hand and computational systems on the other. In doing so, the book gives the reader the modeling and design skills they need to build smart, IT-enabled products. Starting with a look at various examples and characteristics of Cyber-Physical Systems, the book progresses to explain how the area brings together several previously distinct ones such as Embedded Systems, Control Theory, and Mechatronics. Featuring a simulation-based project that focuses on a robotics problem (how to design a robot that can play ping-pong) as a useful example of a CPS domain, Cyber-Physical Systems: A Model-Based Approach demonstrates the intimate coupling between cyber and physical components, and how designing robots reveals several non-trivial control problems, significant embedded and real-time computation requirements, and a need to consider issues of communication and preconceptions

Framework for Evaluating the Readiness of Cyber First Responders Responsible for Critical Infrastructure Protection

First responders go through rigorous training and evaluation to ensure they are adequately prepared for an emergency. As an example, firefighters continually evaluate the readiness of their personnel using a defined set of criteria to measure performance for fire suppression and rescue procedures. From a cyber security standpoint, however, this same set of criteria and rigor is severely lacking for the professionals that must detect, respond to and recover from a cyber-based attack against the nation\u27s critical infrastructure. This research provides a framework for evaluating the readiness of cyber first responders responsible for critical infrastructure protection. The framework demonstrates the development of evaluation environment, criteria and scenarios that are modeled from NFPA 1410 standards concept that is used for assessing the readiness of firefighters. The utility of framework is exhibited during a military cyber training exercise and demonstrates the ability to evaluate the readiness of cyber first responders for industrial control systems when responding to the cyber-based attacks in the scenarios. Although successful, the results and analysis provide a context to develop a physical processes simulation tool, called Y-Box. The Y-Box creates more accessible, representational, realistic and evaluation-friendly environment to enhance the framework. The Y-Box demonstrates its application through the simulation of the first two stages in a wastewater treatment plant. Its performance test demonstrates its ability to interface with different types of signals from multiple programmable logic controllers with an acceptable range of error. The utility of simulation is extended with the development of potential attacks that can be used in a cyber exercise involving industrial control systems

Framework for Evaluating the Readiness of Cyber First Responders Responsible for Critical Infrastructure Protection

First responders go through rigorous training and evaluation to ensure they are adequately prepared for an emergency. As an example, firefighters continually evaluate the readiness of their personnel using a defined set of criteria to measure performance for fire suppression and rescue procedures. From a cyber security standpoint, however, this same set of criteria and rigor is severely lacking for the professionals that must detect, respond to and recover from a cyber-based attack against the nation\u27s critical infrastructure. This research provides a framework for evaluating the readiness of cyber first responders responsible for critical infrastructure protection. The framework demonstrates the development of evaluation environment, criteria and scenarios that are modeled from NFPA 1410 standards concept that is used for assessing the readiness of firefighters. The utility of framework is exhibited during a military cyber training exercise and demonstrates the ability to evaluate the readiness of cyber first responders for industrial control systems when responding to the cyber-based attacks in the scenarios. Although successful, the results and analysis provide a context to develop a physical processes simulation tool, called Y-Box. The Y-Box creates more accessible, representational, realistic and evaluation-friendly environment to enhance the framework. The Y-Box demonstrates its application through the simulation of the first two stages in a wastewater treatment plant. Its performance test demonstrates its ability to interface with different types of signals from multiple programmable logic controllers with an acceptable range of error. The utility of simulation is extended with the development of potential attacks that can be used in a cyber exercise involving industrial control systems

Time Management of Heterogeneous Distributed Simulation

Cyber-physical systems (CPS), by their very nature, mix continuous and discrete behavior and are modeled by heterogeneous components. Formal analysis cannot always handle such complex systems and simulation is a necessary step. In particular, distributed simulation is very useful for the validation of CPS for two main reasons: either the CPS itself is distributed (e.g., a fleet of UAVs) or the CPS is too complex and/or has too much models (e.g., an aircraft). We discuss in this paper the impact of distributing the simulation of a system: which are the rules that must be applied to guarantee a correct behavior between the different simulators? If a centralized simulation already exists (using Discrete Event simulation), which hypothesis must be made for the Distributed Discrete Event simulation? The co-simulation framework used and discussed in this work is Ptolemy-HLA. It allows a Ptolemy model to be distributed using the high-level architecture (HLA) standard

Design Space Exploration in Cyber-Physical Systems

Cyber physical systems (CPS) integrate a variety of engineering areas such as control, mechanical and computer engineering in a holistic design effort. While interdependencies between the different disciplines are key attributes of CPS design science, little is known about the impact of design decisions of the cyber part on the overall system qualities. To investigate these interdependencies, this paper proposes a simulation-based Design Space Exploration (DSE) framework that considers detailed cyber system parameters such as cache size, bus width, and voltage levels in addition to physical and control parameters of the CPS. We propose an exploration algorithm that surfs the parameter configurations in the cyber physical sub-systems, in order to approximate the Pareto-optimal design points with regards to the trade-os among the design objectives, such as energy consumption and control stability. We apply the proposed framework to a network control system for an inverted-pendulum application. The presented holistic evaluation of the identified Pareto-points reveals the presence of non-trivial trade-os, which are imposed by the control, physical, and detailed cyber parameters. For instance the identified energy and control optimal design points comprise configurations with a wide range of CPU speeds, sample times and cache configuration following non-trivial zig-zag patterns. The proposed framework could identify and manage those trade-os and, as a result, is an imperative rst step to automate the search for superior CSP configurations

Assessing and augmenting SCADA cyber security: a survey of techniques

SCADA systems monitor and control critical infrastructures of national importance such as power generation and distribution, water supply, transportation networks, and manufacturing facilities. The pervasiveness, miniaturisations and declining costs of internet connectivity have transformed these systems from strictly isolated to highly interconnected networks. The connectivity provides immense benefits such as reliability, scalability and remote connectivity, but at the same time exposes an otherwise isolated and secure system, to global cyber security threats. This inevitable transformation to highly connected systems thus necessitates effective security safeguards to be in place as any compromise or downtime of SCADA systems can have severe economic, safety and security ramifications. One way to ensure vital asset protection is to adopt a viewpoint similar to an attacker to determine weaknesses and loopholes in defences. Such mind sets help to identify and fix potential breaches before their exploitation. This paper surveys tools and techniques to uncover SCADA system vulnerabilities. A comprehensive review of the selected approaches is provided along with their applicability