An Investigation into the testing and commissioning requirements of IEC 61850 Station Bus Substations

The emergence of the new IEC 61850 standard generates a potential to deliver a safe, reliable and effective cost reduction in the way substations are designed and constructed. The IEC 61850 Station Bus systems architecture for a substation protection and automation system is based on a horizontal communication concept replicating what conventional copper wiring performed between Intelligent Electronic Devices (IED’s). The protection and control signals that are traditionally sent and received across a network of copper cables within the substation are now communicated over Ethernet based Local Area Networks (LAN) utilising Generic Object Oriented Substation Event (GOOSE) messages. Implementing a station bus system generates a substantial change to existing design and construction practices. With this significant change, it is critical to develop a methodology for testing and commissioning of protection systems using GOOSE messaging. Analysing current design standards and philosophies established a connection between current conventional practices and future practices using GOOSE messaging at a station bus level. A potential design of the GOOSE messaging protection functions was implemented using the new technology hardware and software. Identification of potential deviations from the design intent, examination of their possible causes and assessment of their consequences was achieved using a Hazard and Operability study (HAZOP). This assessment identified the parts of the intended design that required validating or verifying through the testing and commissioning process. The introduction of a test coverage matrix was developed to identify and optimise the relevant elements, settings, parameters, functions, systems and characteristics that will require validating or verifying through inspection, testing, measurement or simulations during the testing and commissioning process. Research conducted identified hardware and software that would be utilised to validate or verify the IEC 61850 system through inspection, testing, measurement or simulations. The Hazard and Operability study (HAZOP) has been identified as an effective, structured and systematic analysing process that will help identify what hardware, configurations, and functions that require testing and commissioning prior to placing a substation using IEC 61850 Station bus GOOSE messaging into service. This process enables power utilities to understand new challenges and develop testing and commissioning philosophies and quality assurance processes, while providing confidence that the IEC 61850 system will operate in a reliable, effective and secure manner

A test facility for assessing the performance of IEC61850 substation automation designs

Substation Automation Systems have undergone dramatic changes since the introduction of powerful micro-processing and digital communications devices over Ethernet based networks within the substation. Smart, multifunctional relays, known as Intelligent Electronic Devices, or IEDs, have replaced the traditional panels which contained multiple protection relays, control equipment, metering and status indicators. ActewAGL Distribution, a power utility company servicing Canberra, Australia, has recently decided to undertake a review of its substation automation systems throughout its electrical network. As a result, ActewAGL Distribution has decided to investigate the IEC 61850 – Communication Networks and Systems in Substations standard, by constructing a test facility to assess its performance and capability with the view of implementing the standard into its 132/11kV zone substations network in the near future. This report details the literature review, design, construction, and performance evaluation that was undertaken on the IEC 61850 substation automation designs developed with the use of the test facility. The major achievement of this research project has been the successful development and evaluation of a substation automation system that utilised the IEC 61850 standard incorporated with multiple vendor devices

The GOOSE Protocol

The majority of the electrical substations built today conform to the international standard IEC 61850 that uniformly defines the communication between the various intelligent electronic devices (IEDs) of the substation automation system. The success of the standard in substation automation has expanded its application to new areas, such as wind power, hydro power, and smart grids. For this thesis, the most intriguing use of the standard is its application to the communication between the control system of internal combustion engines and other equipment in a power plant. The main objective of this thesis is to gain early experience on the use of the Generic Object Oriented Substation Events (GOOSE) protocol, which is often considered the most prominent communication protocol of IEC 61850. In this thesis, the standard IEC 61850 is described, and its most fundamental concepts are illustrated by clear examples. An application based on open source software has been developed in the Linux-environment in conjunction with this thesis. The application enables two IEDs from different manufacturers to exchange GOOSE messages. The emphasis of the thesis is thus on the presentation of the GOOSE protocol and the developed application. The results show that the GOOSE protocol provides compatible interfaces for information exchange between IEDs provided by different manufacturers, and can be seen as a viable option as a future communication protocol. IEC 61850 will likely be put into service in engine power plants, in the near future. The schedule partially depends on the development of the markets and the requirements of the customers.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

On reliability and performance analyses of IEC 61850 for digital SAS

fi=vertaisarvioitu|en=peerReviewed

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

Consideration of the IEC 61850 protocol and implications for substation engineering.

Master of Science in Electrical Engineering. University of KwaZulu-Natal, Durban, 2018.This dissertation presented a study on the future-proof IEC 61850 communication protocol and its implications for substation engineering. The advent of contemporary technologies has resulted in the decentralization of substation architecture. Over the last 15 years the IEC 61850 protocol has been contributing to the refurbishment and upgrade of conventional substations. As the aging infrastructure of these centres has been slowly replaced, the hybrid substation has begun to emerge. These substations have been known to contain tedious combinations of different proprietary protocols all attempting to operate within the same substation network. Therefore, the introduction of IEC 61850 to old substations can have an effect on automation, protection and communication within the substations local environment. In this dissertation a multi-protocol substation communication network and SCADA was established using DNP3, Modbus RTU and IEC 61850. A communication network was developed between a physical nexus of connected IEDs and end equipment. It was from this model that the operation of a typical substation automation system was analysed. This critical assessment focussed on the workings of the remotecontrol points as well as the response of end equipment under fault conditions such as breaker fail, overcurrent and earth fault. In addition to the operation of the multi-protocol model, individual inferences could be drawn from the implementation of the aforementioned protocols themselves. These deductions related to the significance of time stamped data, the reduction of cross-wired copper cables within substations, the obvious limitations of serial RS 485 Modbus RTU and the convenient benefits of ‘virtual’ networks. It was during the main research phase of this study that the principal benefits of the IEC 61850 standard were readily enforced and interpreted. Furthermore, special consideration was given to the implications of the GOOSE message class on substation protection. It was here that GOOSEbased breaker fail protection, arc-flash protection and blocking response were investigated. As a result of the implementation of these protection schemes it was determined that GOOSE messaging and by extension the IEC 61850 standard provides optimisation, economic benefits as well as revolutionary advancements in protection and automation to substations. The IEC 61850 substation standard is current, universal, promotes the interoperability between devices and is a leading contributor in the development of smart grids. Therefore, IEC 61850 is a standard of the present and of the future

A study of the applicability of software-defined networking in industrial networks

173 p.Las redes industriales interconectan sensores y actuadores para llevar a cabo funciones de monitorización, control y protección en diferentes entornos, tales como sistemas de transporte o sistemas de automatización industrial. Estos sistemas ciberfísicos generalmente están soportados por múltiples redes de datos, ya sean cableadas o inalámbricas, a las cuales demandan nuevas prestaciones, de forma que el control y gestión de tales redes deben estar acoplados a las condiciones del propio sistema industrial. De este modo, aparecen requisitos relacionados con la flexibilidad, mantenibilidad y adaptabilidad, al mismo tiempo que las restricciones de calidad de servicio no se vean afectadas. Sin embargo, las estrategias de control de red tradicionales generalmente no se adaptan eficientemente a entornos cada vez más dinámicos y heterogéneos.Tras definir un conjunto de requerimientos de red y analizar las limitaciones de las soluciones actuales, se deduce que un control provisto independientemente de los propios dispositivos de red añadiría flexibilidad a dichas redes. Por consiguiente, la presente tesis explora la aplicabilidad de las redes definidas por software (Software-Defined Networking, SDN) en sistemas de automatización industrial. Para llevar a cabo este enfoque, se ha tomado como caso de estudio las redes de automatización basadas en el estándar IEC 61850, el cual es ampliamente usado en el diseño de las redes de comunicaciones en sistemas de distribución de energía, tales como las subestaciones eléctricas. El estándar IEC 61850 define diferentes servicios y protocolos con altos requisitos en terminos de latencia y disponibilidad de la red, los cuales han de ser satisfechos mediante técnicas de ingeniería de tráfico. Como resultado, aprovechando la flexibilidad y programabilidad ofrecidas por las redes definidas por software, en esta tesis se propone una arquitectura de control basada en el protocolo OpenFlow que, incluyendo tecnologías de gestión y monitorización de red, permite establecer políticas de tráfico acorde a su prioridad y al estado de la red.Además, las subestaciones eléctricas son un ejemplo representativo de infraestructura crítica, que son aquellas en las que un fallo puede resultar en graves pérdidas económicas, daños físicos y materiales. De esta forma, tales sistemas deben ser extremadamente seguros y robustos, por lo que es conveniente la implementación de topologías redundantes que ofrezcan un tiempo de reacción ante fallos mínimo. Con tal objetivo, el estándar IEC 62439-3 define los protocolos Parallel Redundancy Protocol (PRP) y High-availability Seamless Redundancy (HSR), los cuales garantizan un tiempo de recuperación nulo en caso de fallo mediante la redundancia activa de datos en redes Ethernet. Sin embargo, la gestión de redes basadas en PRP y HSR es estática e inflexible, lo que, añadido a la reducción de ancho de banda debida la duplicación de datos, hace difícil un control eficiente de los recursos disponibles. En dicho sentido, esta tesis propone control de la redundancia basado en el paradigma SDN para un aprovechamiento eficiente de topologías malladas, al mismo tiempo que se garantiza la disponibilidad de las aplicaciones de control y monitorización. En particular, se discute cómo el protocolo OpenFlow permite a un controlador externo configurar múltiples caminos redundantes entre dispositivos con varias interfaces de red, así como en entornos inalámbricos. De esta forma, los servicios críticos pueden protegerse en situaciones de interferencia y movilidad.La evaluación de la idoneidad de las soluciones propuestas ha sido llevada a cabo, principalmente, mediante la emulación de diferentes topologías y tipos de tráfico. Igualmente, se ha estudiado analítica y experimentalmente cómo afecta a la latencia el poder reducir el número de saltos en las comunicaciones con respecto al uso de un árbol de expansión, así como balancear la carga en una red de nivel 2. Además, se ha realizado un análisis de la mejora de la eficiencia en el uso de los recursos de red y la robustez alcanzada con la combinación de los protocolos PRP y HSR con un control llevado a cabo mediante OpenFlow. Estos resultados muestran que el modelo SDN podría mejorar significativamente las prestaciones de una red industrial de misión crítica

Protection of Microgrids: A Scalable and Topology Agnostic Scheme With Self-Healing Dynamic Reconfiguration

Momentum towards realizing the smart grid will continue to result in high penetration of renewable fed Distributed Energy Resources (DERs) in the Electric Power System (EPS). These DERs will most likely be Inverter Based Resources(IBRs) and will be an integral part of the distribution system in the near future. The drive towards resiliency with these IBRs will enable a modular topology where several microgrids are tied together, operating synchronously to form the future EPS at the distribution level. Since the microgrids can evolve from existing distribution feeders, they will be unbalanced in load, phases, and feeder impedances. A typical control strategy of a conventional inverter that follows the grid voltage and frequency while injecting positive-sequence current can lead to undesirable performance for the unbalanced systems, especially in the islanded mode of operation. So, the dissertation will first focus on the control aspect of IBRs in an unbalanced system. Acceptable operating conditions with stability against disturbances and faults are the primary focus. For the proper functioning of these microgrids, there is a need for grid-forming inverters that can enable acceptable performance and coexist with conventional grid-following inverters that supply only positive-sequence currents. In addition to the control objectives, limiting inverter output during faulted or overload conditions with a current limiter is essential. These control objectives can be implemented in both the synchronous reference frame ($dq$ coordinates) and the natural reference frame ($abc$ coordinates). Hence a comparison study is performed to understand the merit of each implementation related to this specific topology. As 100\% IBR-based microgrid becomes an integral part of the distribution system, the issues and challenges arising from its implementation should be addressed for successful operation. Designing reliable protection is one of the significant challenges for microgrids. Most microgrid protection schemes found in published literature suffer from a lack of generality. They work well for the assumed topology, including the type and placement of sources. Other generic protection schemes tend to be too complicated, expensive, or both. To overcome these drawbacks, a topology-agnostic, scalable, and cost-aware protection based on fundamental principles is developed that works in the presence of high penetration of inverter-based resources (IBRs). The protection system includes primary and backup. It also implements stable automatic reconfiguration of the healthy sections of the system after clearance of fault, thus increasing resilience by self-healing. The scheme is validated in PSCAD for primary and backup protection and reconfiguration on the IEEE 123-node feeder in grid-connected and islanded modes with 15 IBRs connected to the system. As the designed protection scheme requires communication between protective devices and the microgrid controller, the method must be validated in real-time with cyber-physical co-simulation for a successful demonstration. In this regard, a Hardware-In-the-Loop (HIL) platform between a simulated power system model using RTDS and physical protective devices is built. In the HIL platform, the primary protection of the scheme is programmed in SEL 421-7 relay, and backup protection is programmed in MATLAB on a generic computer acting as a microgrid controller. The IEC 61850 models are used to communicate between the SEL-421-7 relay and RTDS, whereas TCP/IP communication connects the microgrid controller to RTDS. The focus of the work is to demonstrate the co-simulation platform with communication links established using both protocols and validate the proposed scheme in real-time on the IEEE 123 node distribution feeder. The IEC 61850 and TCP/IP communications configuration are discussed as the interface requires proper hardware and software setup. The real-time performance indicates the Hardware In the Loop (HIL) framework as a competent testing environment for the developed protection scheme for microgrids. In summary, a scalable and topology agnostic protection scheme with self-healing dynamic reconfiguration is developed for microgrids. Clear guidelines for implementation of the proposed scheme on any microgrid topology are also described