Project Summary

Building the IntelliGrid Architecture

In daily use, the term ‘architecture’ refers to the overall plan, style, and vision for a structure. It also refers to the general study of the principles of building. It is vital that any network architecture be based on the requirements for the use of the final structure, in the same way that the architecture of a building must be tailored to the needs of its inhabitants and the environment in which it is located.

Following this definition, IntelliGrid Architecture is both a plan for the integrated power system infrastructure and a study of the requirements and principles required to make particular automation projects work. In basic terms, the IntelliGrid Architecture is a set of components and the rules to interconnect individual components. IntelliGrid Architecture endeavors to define reusable architectural components and a common set of interfaces, or ‘languages’ that can be used to execute energy enterprise and industry-wide applications. To meet future use requirements, IntelliGrid Architecture is based on the specific needs of the power industry in the same way a building’s architecture is tailored to the needs of its owners.

To develop IntelliGrid Architecture, a diverse team of industry experts was assembled with representation from utilities, vendors, consultants, researchers, and project managers. This team followed established steps of ‘good system architecture design’, specifically:

1.     Gathering requirements from stakeholders across the industry.

2.     Analyzing the requirements using modern methodologies and tools.

3.     Evaluating the state-of-the-art in communications technology.

4.     Designing the architecture by identifying common components and services.

5.     Capturing the architecture design and recommendations using web technology.

 

Three key steps of system architecture design remain to be executed:

§       Testing the principles of the architecture in prototypes and pilot projects.

§       Implementation and validation of the design in real-world, large-scale systems.

§       Integration of the lessons learned into further iterations of the process.

 

The Integrated Energy and Communication System Architecture – IntelliGrid Architecture – is a first step in enabling this vision. As the title suggests, IntelliGrid Architecture is intended to integrate two different systems: the physical energy delivery system, and the communications network of intelligent equipment that controls it.

As we look to the future of the power system, it will rely increasingly on this second infrastructure of information exchange. It must be developed in parallel to the power system infrastructure to effectively move the industry toward its identified and future goals. This second infrastructure will be comprised of advanced communications and networking technologies working with intelligent equipment and algorithms that can execute increasingly sophisticated operations functions.

As long as the two networks are dealt with separately by utilities and other power system organizations, the power industry will be plagued with ‘islands of integration’, in which the vision is realized only in selected areas and not on a scale large enough to ensure future visions of system operation.

 

1. Gathering Requirements – Past, Present and Future

When developing IntelliGrid Architecture, it was vital that the architecture be based on a clear understanding of the needs of the power system network in five or ten years, not only based on today’s requirements. If future needs are not considered, the resulting architecture would be obsolete by the time it was actually built. To this end, part of the requirements process involved interaction with more than 1,000 individuals during more than 100 engagements.

The information gathered during these engagements was captured in a ‘template’ format that formalized the type of information required from each stakeholder. The ideal goal would have been to capture both current and future communication system requirements from representatives in all functions and applications performed in the utility industry. This level of requirements gathering was, however, an enormous job and it was beyond the resources of the project to complete in time for the results to be useful.

Instead, the requirements gathering process did cover existing requirements lightly, but focused on the three primary growth areas that were determined by IntelliGrid Architecture team to most likely pose architectural challenges for the information infrastructure. These growth areas included:

§    Wide Area Measurement and Control – in particular, those requirements for developing a self-healing, self-optimizing grid that can predict emergencies, rather than just react to them, and that automates many reliability functions currently performed manually, or not at all

§       Advanced Distribution Automation – including the challenges raised by using Distributed Energy Resources, renewable energy sources, fault detection, fault location, sectionalization and automatic service restoration over large service territories and multiple organizational boundaries

§       Customer Interface – including the challenges of real-time pricing, demand response, automatic metering, integrating the communications network with building automation, and the requirements for integrating real-time data gathered from the power network with business policies to enable secure trading in a deregulated environment

2. Analyzing Areas of Concern

After the requirement gathering process was complete, common themes quickly became apparent as IntelliGrid Architecture program team analyzed stakeholder requirements. It was clear that the architecture must provide common strategies in several areas that underlie nearly all requirements information gathered. The common themes uncovered during the information gathering process include:

§    Basic Networking and Connectivity Infrastructure. In particular, how will the myriads of device and communications technologies connect? In general, IP-based networks presented an obvious solution to the project team because of their widespread use in general computing.  However, utility requirements for reliability, wireless access, changing configurations, and quality of service dictate special guidelines for using IP, and for using other technologies in particular environments.

§       Security and Access Control. Deregulation and other effects of the Digital Society are forcing utilities to rely on public networks provided by third parties, to communicate with competitors, cross organizational boundaries, and to expand their communication networks (both inward to their own organizations and outward to the customer). These requirements make the need for cyber-security ubiquitous in power system operations. Encryption and authentication technologies abound, but the focus of IntelliGrid Architecture security strategy is to tailor security solutions to particular problem domains, and link them together with shared security management services.

§       Data Management. The sheer volume and variety of data required to operate a power system within the Digital Society poses a staggering challenge when standardizing interfaces for reading, writing, publishing, and subscribing to data. In this area, the key strategy will be to identify standardized common object models that can serve as building blocks for common services and applications.

§       Network and System (Enterprise) Management. For an area that is relatively mature in commercial networks, the science of monitoring and controlling the communications network is surprisingly primitive, or even unknown, in power system automation. The key here will be to harmonize network monitoring technologies and network object models with the functional equivalents in the power industry and then integrating both with security management.

The analysis was also guided by the following engineering principles:

§       Business Needs of the power system industry, as captured in the power system operations functions, and categorized into IntelliGrid Architecture Environments

§       Strategic Vision based on high level concepts of distributed information

§       Tactical Approach based on technology independent techniques of common services, information models, and generic interfaces.

§       Standard Technologies and Best Practices that could be used in the power industry

§       Methodology for automation architects, power system planners, project engineers, information specialists, and other IntelliGrid Architecture users to zone in on the exact parts of the IntelliGrid Architecture that is directly relevant to them, and to quickly access IntelliGrid Architecture recommendations. 

IntelliGrid Architecture generalizes and extracts the architecturally significant requirements by cross-cutting energy industry requirements involving distributed information, and provides a technology-independent architecture for project engineers to use as they determine solutions for specific implementations.

3. Evaluating the State-of-the-Art

Equipped with requirements gathered from the industry and general strategies for approaching key problem areas, IntelliGrid Architecture team next considered which communications technologies and best practices it could use to build the architecture. For the purposes of developing the architecture, the term ‘technology’ had a very wide definition and could include a protocol, a database format, an object model, or a policy, among other things. Toward this purpose, the team ‘cast its net’ as widely as possible.  It evaluated technologies from:

 

§       Multiple organizations.  The team was committed to the creation of open systems, and preferred to use international standards whenever possible.  However, some of the best technologies available have been created by government bodies, industry consortia, and even private organizations.  Technologies from all of these bodies were considered. 

§       Multiple applications.  It was likely that technologies developed for one part of the power industry would be useful in other parts.  Therefore the team considered technologies from protection, control, monitoring, metering, consumer access, and all other parts of the power industry equally.

§       Multiple industries. For the architecture to be truly integrated, it needed to incorporate the best innovations not just from the power industry, but also from desktop computing, telephony, industrial automation, other utilities, business-to-business and of course the Internet community, among other industries.  These technologies were considered key to bringing the power industry into the digital society. 

§       Multiple disciplines.  Not just ‘hard’ technologies, but also best practices and procedural improvements were considered, where they related to communications.  This was vital in areas such as security management, which depend as much on the human factor as on electronics or software.

The team actually analyzed technologies twice: once prior to designing the architecture, to determine what ‘building blocks’ were available, and again after designing the architecture, to determine the list of technologies and best practices that the team would recommend for use in the design.  In both cases, technologies were grouped into the four ‘problem areas’ discussed earlier: basic networking, security, data management, and enterprise management.  Data management and basic networking were subsequently reorganized into utility-specific and non-utility technologies for ease of reference.

Each technology was evaluated for its strengths and weaknesses.  The team captured these in a brief paragraph for each technology, including web references where IntelliGrid Architecture users could find more information, and keywords for searching for particular technologies.

The team quickly realized that unlike some previous attempts to ‘unify’ utility communications, IntelliGrid Architecture could not recommend a single set of technologies for use everywhere in the industry.  Therefore, the team developed the concept of IntelliGrid Architecture environments.  Based on the stakeholder input, they identified over twenty different logical areas having common communications requirements, and made technology recommendations in each of these ‘environments’.  The team captured these technology recommendations in text and as a system of interlinked web pages.

4. Designing the Architecture

The design step brought together all that had come before: requirements gathering, strategy, and technology analysis. The resulting architecture is based on the following principles:

§       Using the science data modeling to capture and analyze requirements in ‘use cases’.

§       Using layered technologies to separate levels of abstraction and functionality.

§       Creating common information models and identifying common services and generic interfaces to create a technology-independent representation of the architecture.

§       Making use of self-description (plug-and-play) and ‘meta-data’ (descriptive information about data) to reduce configuration effort and error, and to facilitate automatic translation between technologies.

§       Defining a number of utility-specific environments having common sets of requirements, as discussed in the previous section

§       Identifying missing or overlapping technologies as a tool for making technology recommendations in each of the identified environments.

IntelliGrid Architecture’s technology-independence can be summarized in Figure 2. It consists of a ‘backbone’ of common information models and services primarily based around the IEC 61850, IEC 61968 and IEC 61970 standards.

The common ‘nouns’ and ‘verbs’ of these exchange models are translated into a variety of different technologies for communicating in different environments. As discussed earlier, IntelliGrid Architecture provides a tailored list of recommended technologies for each of the ‘use case steps’ and ‘environments’ that were identified through the requirements gathering and analysis processes.

It is important to note that IntelliGrid Architecture ‘backbone’ is a logical structure, not a physical one.  Translation from one technology to another may take place at many different places in the network.  The translation function itself may be implemented on a variety of devices and using a variety of technologies. 

However, the core concept of IntelliGrid Architecture is that all devices within the network will eventually be able to communicate with each other.  The common information models and services make it possible to easily and economically convey information without loss of fidelity across ownership and functional boundaries.  Basing these information models and translators on self-description permits the network to quickly adapt to new technologies, applications, and devices.

5 . Capturing the results

IntelliGrid Architecture is delivered in four volumes and a system of several hundred web pages. The deliverable components of IntelliGrid Architecture answer the following questions:

§       The Value Story – What are the drivers/benefits of an IntelliGrid Architecture? What is the economic justification?

§       Requirements identification – What types of data must be exchanged in an integrated power system? What functions must be performed? What knowledge will be needed in the 5 to 10 year horizon to build the supporting infrastructure now?

§       Analysis of the requirements – What requirements do the messages exchanged within the power system have in common? Which requirements can be met by similar technologies? Which functions should be performed centrally and which should be distributed through the system?

§       Identification of future needs – Not all the requirements that were identified can be implemented today. What technical areas need to be developed now in order to facilitate the integration of the power system in the future?

§       Terminology and Tools – What tools exist for identifying, capturing and manipulating requirements? What language can we use to describe the power system of the future clearly enough to ensure interoperability?

§       Recommendations – What practices need to be adopted universally in order to make an integrated power system a reality? What specific technologies should organizations use in their networks? What steps do standards organizations, governments, and consortia need to take?

§       Model of future operations – How can we simulate the power system accurately enough to predict future needs?  How can we describe new power system applications in a way that identifies their communications needs?  IntelliGrid Architecture provides industry-standard diagrams that graphically show the interactions among the various ‘actors’ and ‘data items’ in the functional areas explored.

These concepts are described in much greater detail within the body of Volumes I and IV. The organizational structure of the volumes is shown in the following table:

 

Recommendations for the Future

The first volume contains IntelliGrid Architecture team’s recommendations for the future. These recommendations are divided into several categories:

§       Encouraging power system organizations to design networks using an architecture approach

§       Contributing to standards development organizations and consortia

§       Sponsoring pilot projects and field trials

§       Developing engineering tools and notation methods

§       Integrating IntelliGrid Architecture with other architectures

§       Encouraging the adoption of IntelliGrid Architecture concepts and recommendations

§       Initiating work to continue systems analysis of the utility industry in more detail

There are too many recommendations to capture in this project summary, but common themes can be identified as follows:

§       Harmonize the existing common services, information models, and interfaces, as well as create new standards where they are needed, so the power industry speaks a common communications language of ‘nouns’ and ‘verbs’ that can be translated into different technologies. This is a key requirement for the higher levels of system integration now emerging across the energy industry

§       Integrate security, systems, network management, and technical development (i.e. new technologies), which have too often been considered separate tasks.

§       Unify technologies between power system automation networks, corporate networks, and inter-business networks, again by linking them to common information models, services, and interfaces.

§       Remember that developing an industry-level architecture is a process – not an end point. Requirements and enabling technologies are constantly changing. Although the guiding principles should remain constant, individual solutions will change over time.

Next Steps

The five steps discussed in this summary have captured an initial set of the power system’s operational requirements and the proposed design for IntelliGrid Architecture. However, three key steps of system architecture design remain to be executed:

§       Testing the principles of the architecture in prototypes and pilot projects.

§       Implementing and validating the design in real-world, large-scale systems.

§       Feeding back the lessons learned back into another iteration of the process.

Designing IntelliGrid Architecture is just a start. IntelliGrid Architecture must now be built, proven, and continuously improved upon so that the vision of a power system integrated with its communication system can be realized.