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Example of Using the IntelliGrid Architecture:

Protection Engineer Reviews and Modify Protection Settings

Among the many potential IntelliGrid Architecture uses, this section presents but one example, in some detail, to illustrate how one can obtain benefits from IntelliGrid Architecture.

Statement of the Problem – Protection Planning Engineer

A protection engineer wants to review fault recorder information and modify settings in a protection device in a substation. She currently uses a dial-up modem from her workstation (which is connected to a modem bank through the corporate network) to the substation to review the information, but then must physically travel (or send someone) to the substation to modify the settings. This system has been in place a number of years and has worked reasonably well. However, the engineer has been told that all dial-up modems must be eliminated due to security concerns. Also, as staffing has been reduced, traveling to the substation herself, or sending someone, must be minimized. What to do?

The protection engineer goes to the Power System Functions on IntelliGrid Architecture website (or the Use Cases narratives in Volume 2) and finds a function (Transmission Operations – Automated Control Baseline) that is similar to her situation. She does note some differences, however. First, the Automated Control function assumes that protection devices can be accessed through a ‘substation master’, but in her situation, each protection device must be accessed separately. She is also aware that most of the protection devices are not configured to allow remote updating of settings (for security reasons), while the function assumes remote updates can be made. While this function is therefore not a perfect solution for the engineer, it is a strong start.

Engineering the Solution – Project Engineer

The protection engineer goes to the project engineer for help in the next steps. She shows him the Automated Control function on his computer by linking to IntelliGrid Architecture website and quickly jumping to the appropriate page. She explains what she needs and now it is similar but still somewhat different from the description of the function.

The project engineer quickly scrolls down to the Steps section of the Automated Control function and starts reviewing the steps until he finds the step that is closest to the problem she has identified. Scanning over to the Environments column, he realizes that the closest IntelliGrid Architecture Environment to what she needs is the Critical Operations Intra-Substation Environment. He clicks on the link in the step.

Requirements

The Automated Control function’s requirements have identified the following as key requirements which links to the Critical Operations Intra-Substation Environment:

§ Configuration Requirements

– Provide point-to-point interactions between two entities

– Support peer to peer interactions

– Support interactions within a contained environment (e.g. substation or control center)

§ Quality of Service Requirements

– Provide high speed messaging of less than 1 second

– Support very high availability of information flows of 99.99+ (~1 hour)

– Support time synchronization of data for age and time-skew information

§ Security Requirements

– Provide Authorization Service for Access Control (resolving a policy-based access control decision to ensure authorized entities have appropriate access rights and authorized access is not denied)

– Provide Information Integrity Service (data has not been subject to unauthorized changes or these unauthorized changes are detected)

– Provide Audit Service (responsible for producing records, which track security relevant events)

– Provide Credential Renewal Service (notify users prior to expiration of their credentials)

– Provide Security Policy Service (concerned with the management of security policies)

– Provide Single Sign-On Service (relieve an entity having successfully completed the act of authentication once from the need to participate in re-authentications upon subsequent accesses to managed resources for some reasonable period of time)

– Provide Security Discovery (the ability to determine what security services are available for use)

§ Network and System Management Requirements

– Provide Network Management (management of media, transport, and communication nodes)

– Provide System Management (management of end devices and applications)

§ Data Management Requirements

– Support the management of large volumes of data flows

– Support keeping the data up-to-date

– Support extensive data validation procedures

– Support specific standardized or de facto object models of data

– Provide discovery service (discovering available services and their characteristics)

– Provide conversion and protocol mapping

IntelliGrid Architecture High Level Concepts

These requirements link to a number of recommended technologies, services, and best practices that are based on the IntelliGrid Architecture High Level Concepts. Therefore, the project engineer first reads through the IntelliGrid Architecture High Level Concepts by clicking on the different topics under ‘IntelliGrid Architecture Framework’. These topics include:

§ Abstract modeling

§ Security services, risk assessment, and policies

§ System and network management services

§ Data management issues

§ Integration and interoperability

The project engineer notes that they have been advocating object-oriented approaches for a few years, but has run into ‘legacy system’ issues and lack of management support that have prevented him from moving forward in that direction.

Platform Independent Model

The project engineer should understand how the high level concepts are realized in a technology independent way. While the exact technology used to implement the architecture may vary from vendor to vendor or over time, the Platform Independent Model provides continuity to ensure that a unified approach is maintained. Additionally, the Platform Independent Model provides for a level of interoperability that cannot be achieved via just the specification of high-level concepts and technology.

Recommended Technologies, Services, and Best Practices

Next, he examines the technologies identified as recommended and alternative solutions for the Critical Operations Intra-Substation Environment. These recommended technologies and alternative solutions include the following (in part).

§ Energy Industry-Specific Technologies

– ISO 9506 MMS–Manufacturing Messaging Specification - Configuration, Quality of Service,

– IEC61850–Substation Automation Communications - Configuration,

– IEC61850 Part 7-2–GSE (GOOSE and GSSE - Configuration, Quality of Service,

– IEC61850 Part 7-2–SMV (Sampled Measured Values) - Configuration,

– IEC61850 Part 7-2–Abstract Common Services Interface (ACSI) - Configuration, Quality of Service, Data Management

– IEC61850 Parts 7-3 and 7-4–Substation Object Modeling - Network Management, Data Management

– IEC61850 Part 6–Substation Configuration Language - Network Management, Data Management

– IEC61850 Power Quality Object Models - Data Management

§ Security Functionality

– FIPS 197 for Advanced Encryption Standard (AES) - Security,

– Role-Based Access Control - Security,

– FIPS 186 Digital Signatures Standard (DSS) - Security,

– Intrusion Detection Technologies - Security, Network Management,

– Intrusion Prevention Systems (IPS) - Security, Network Management,

– Service Level Agreements (SLA) - Security,

§ Network and System Management Functionality

– Simple Network Management Protocol (SNMP) - Network Management,

– IEC 62351-7 Objects for Network Management - Quality of Service, Network Management, Data Management

The project engineer has heard of AES but isn’t really sure what it is and where it stands in terms of being implemented by vendors. IEC61850 is just a number and he hasn’t a clue what it is. He is quite familiar with SNMP, but has never heard of it being used within a substation. This intrigues him, because he has been under increasing pressure from the IT department to implement Internet-based technologies. If it really pans out that SNMP could help him solve her problem, then he will have killed two birds with one stone.

Use of UML to Develop Specific Use Case

However, spurred by the IntelliGrid Architecture concept of using UML for abstract modeling of functions, and with the help of one of his IT colleagues, he reviews the UML diagrams of the Automated Control function by going to the detailed UML-based Use Case links on IntelliGrid Architecture website, and finding the detailed analysis of the Automated Control Use Case. He creates a similar one that reflects the situation in his utility and the specific needs of the protection engineer. He reviews this with the protection engineer who, after adding some more details, agrees that conceptually it meets her requirements. But the question of how has still not been resolved.

Use of Environments to Determine Solutions

The project engineer now delves into the technologies, services, and best practices that were associated with IntelliGrid Architecture Environment. Ultimately he decides to:

1. Recommend using VPNs between the corporate network and the substation router, along with very strict role-based access control, passwords, and a strongly worded and enforced security policy. This will allow protection engineers to have direct access to the substation equipment again, now that the modems have been taken out.

2. Recommend the time synchronization of all substation protection devices using GPS devices. However, other devices can be time synched using the SNTP protocol.

3. Recommend using IEC61850 for all new protection IEDs, but with dual ports so that the SCADA system can continue to receive its data from the protection IED via DNP. This approach will provide protection engineers with more information, more accurate timestamp information, and more easily maintained data management.

4. Recommend that all data, including IEC61850 objects and CIM-based objects, use XML schemas to represent their metadata. This approach would permit protection engineers to browse the XML-structured metadata objects, pick the information of interest, and have this data automatically included in their access list (if permitted under the security access control).

5. Recommend the implementation of data ‘brokers’ using the publish/subscribe service to update databases. These brokers will manage data across multiple networks, thus ensuring that key data is consistent across all databases. This data management system would include backup systems, automatic update of databases if they were off-line, roll-back of data if warranted, and other tools for managing data.

Architecting for the Future – Automation Architect

After the project engineer completes his tasks in supporting the protection engineer, he sets up a meeting with the CIO of his company. He shows her IntelliGrid Architecture website and the web pages describing IntelliGrid Architecture high level concepts. She acknowledges that she has heard about IntelliGrid Architecture project and that it was making architectural recommendations, but that she had not quite gotten around to checking it out. She agrees it is time for her and her staff to do so.

She clicks on the Executive Summary and the Project Summary to get a very quick overview of the project, and then jumps to the Recommendations. She sees there the recommendations to:

§ “Adopt the IntelliGrid Architecture as the strategic vision for your information infrastructure”

§ “Create systems architect positions”

§ “Think in architectures, not projects”

After reviewing these recommendations in more detail, and discussing the concepts and possibilities with her staff, she develops a position paper using many of the arguments discussed in IntelliGrid Architecture recommendations. She presents this to the other executives, shows them the Executive Summary from IntelliGrid Architecture website, and gets their overall concurrence, with the understanding that although IntelliGrid Architecture concepts are indeed the strategic vision, individual decisions will need to be made on actually implementing specific technologies, based on financial and technical situations.

The CIO agrees with these provisos, appoints an ‘Automation Architect’, and requests that he develop a more detailed plan for implementing IntelliGrid Architecture recommendations.