Biblio

Modern day grid operation requires multiple interlinked applications and many automated processes at control center for monitoring and operation of grid. Information technology integrated with operational technology plays a critical role in grid operation. Computing resource requirements of these software applications varies widely and includes high processing applications, high Input/Output (I/O) sensitive applications and applications with low resource requirements. Present day grid operation control center uses various applications for load despatch schedule management, various real-time analytics & optimization applications, post despatch analysis and reporting applications etc. These applications are integrated with Operational Technology (OT) like Data acquisition system / Energy management system (SCADA/EMS), Wide Area Measurement System (WAMS) etc. This paper discusses various design considerations and implementation of converged infrastructure through virtualization technology by consolidation of servers and storages using multi-cluster approach to meet high availability requirement of the applications and achieve desired objectives of grid control center of north eastern region in India. The process involves weighing benefits of different architecture solution, grouping of application hosts, making multiple clusters with reliability and security considerations, and designing suitable infrastructure to meet all end objectives. Reliability, enhanced resource utilization, economic factors, storage and physical node selection, integration issues with OT systems and optimization of cost are the prime design considerations. Modalities adopted to minimize downtime of critical systems for grid operation during migration from the existing infrastructure and integration with OT systems of North Eastern Regional Load Despatch Center are also elaborated in this paper.

Quasi-Realistic cyber-physical system (QR-CPS) testbed architecture and operational environment are critical for testing and validating various cyber attack-defense algorithms for the wide-area resilient power systems. These QR-CPS testbed environments provide a realistic platform for conducting the Grid Exercise (GridEx), CPS security training, and attack-defense exercise at a broader scale for the cybersecurity of Energy Delivery Systems. The NERC has established a tabletop based GridEx platform for the North American power utilities to demonstrate how they would respond to and recover from cyber threats and incidents. The NERC-GridEx is a bi-annual activity with tabletop attack injects and incidence response management. There is a significant need to build a testbed-based hands-on GridEx for the utilities by leveraging the CPS testbeds, which imitates the pragmatic CPS grid environment. We propose a CPS testbed-based Quasi-Realistic Grid Exercise (QR-GridEx), which is a model after the NERC's tabletop GridEx. We have designed the CPS testbed-based QR-GridEx into two parts. Part-I focuses on the modeling of synthetic grid models for the utilities, including SCADA and WAMS communications, and attack-and-defense software systems; and the Part-II focuses on the incident response management and risk-based CPS grid investment strategies. This paper presents the Part-I of the CPS testbed-based QRGridEx, which includes modeling of the synthetic grid models in the real-time digital simulator, stealthy, and coordinated cyberattack vectors, and integration of intrusion/anomaly detection systems. We have used our existing HIL CPS security testbed to demonstrate the testbed-based QR-GridEx for a Texas-2000 bus US synthetic grid model and the IEEE-39 bus grid models. The experiments demonstrated significant results by 100% real-time performance with zero overruns for grid impact characteristics against stealthy and coordinated cyberattack vectors.

Cyber-event-triggered power grid blackout compels utility operators to intensify cyber-aware and physics-constrained recovery and restoration process. Recently, coordinated cyber attacks on the Ukrainian grid witnessed such a cyber-event-triggered power system blackout. Various cyber-physical system (CPS) testbeds have attempted with multitude designs to analyze such interdependent events and evaluate remedy measures. However, resource constraints and modular integration designs have been significant barriers while modeling large-scale grid models (scalability) and multi-grid isolated models (concurrency) under a single real-time execution environment for the hardware-in-the-loop (HIL) CPS security testbeds. This paper proposes a meticulous design and effective modeling for simulating large-scale grid models and multi-grid isolated models in a HIL realtime digital simulator environment integrated with industry-grade hardware and software systems. We have used our existing HIL CPS security testbed to demonstrate scalability by the realtime performance of a Texas-2000 bus US synthetic grid model and concurrency by the real-time performance of simultaneous ten IEEE-39 bus grid models and an IEEE-118 bus grid model. The experiments demonstrated significant results by 100% realtime performance with zero overruns, low latency while receiving and executing control signals from SEL Relays via IEC-61850 protocol and low latency while computing and transmitting grid data streams including stability measures via IEEE C37.118 synchrophasor data protocol to SEL Phasor Data Concentrators.

Development of an attack-resilient smart grid depends heavily on the availability of a representative environment, such as a Cyber Physical Security (CPS) testbed, to accelerate the transition of state-of-the-art research work to industry deployment by experimental testing and validation. There is an ongoing initiative to develop an interconnected federated testbed to build advanced computing systems and integrated data sharing networks. In this paper, we present a distributed simulation for power system using federated testbed in the context of Wide Area Monitoring System (WAMS) cyber-physical security. In particular, we have applied the transmission line modeling (TLM) technique to split a first order two-bus system into two subsystems: source and load subsystems, which are running in geographically dispersed simulators, while exchanging system variables over the internet. We have leveraged the resources available at Iowa State University's Power Cyber Laboratory (ISU PCL) and the US Army Research Laboratory (US ARL) to perform the distributed simulation, emulate substation and control center networks, and further implement a data integrity attack and physical disturbances targeting WAMS application. Our experimental results reveal the computed wide-area network latency; and model validation errors. Further, we also discuss the high-level conceptual architecture, inspired by NASPInet, necessary for developing the CPS testbed federation.

Security is one of the most important properties of electric power system (EPS). We consider the state estimation (SE) tool as a barrier to the corruption of data on current operating conditions of the EPS. An algorithm for a two-level SE on the basis of SCADA and WAMS measurements is effective in terms of detection of malicious attacks on energy system. The article suggests a methodology to identify cyberattacks on SCADA and WAMS.