Experience Gained and Recommendations for Implementation of Process Bus in Protection, Automation and Control Systems
(Reviewed by Alex Apostolov, USA)
CIGRE Technical Brochure 949 represents a comprehensive and timely assessment of the digital transformation of the electrical power substations worldwide. Published in December 2024 by Working Group B5.69, this 190-page document synthesizes extensive industry experience with IEC 61850 process bus technology, offering both utilities and suppliers invaluable guidance for navigating this fundamental shift in substation design.
The brochure excels in its systematic approach, organizing the material in twelve chapters and three appendices to address every part of the bus implementation process. Beginning with foundational concepts and terminology, it progresses through architectural considerations, economic evaluations and operational experience before concluding with practical recommendations. This logical structure makes the document valuable as both a reference guide and sequential reading material.
Working Group B5.69 reviewed nearly 200 publications and 60 projects covering from demonstration pilots to full-scale deployments across multiple continents. This breadth of coverage, supplemented by an industry survey conducted between September 2020 and January 2021, provides readers with genuinely representative insights rather than vendor-specific perspectives.
Particularly valuable are the detailed case studies examining projects like SP Energy Networks’ FITNESS initiative, Statnett’s Furuset R&D project, and TransGrid’s Avon substation. These real-world examples illustrate both successes and challenges, offering lessons learned that can accelerate adoption while avoiding common pitfalls. The documentation of China’s extensive deployment comprising over 5,000 digital substations provides unique insights into large-scale implementation strategies.
The technical depth is impressive without becoming inaccessible. The brochure carefully explains critical concepts like time synchronization using Precision Time Protocol (PTP), network redundancy through Parallel Redundancy Protocol (PRP) and High-availability Seamless Redundancy (HSR), and the integration of Low Power Instrument Transformers (LPIT). These explanations are supported by clear diagrams and architecture examples that bridge theory and practice.
Chapter 7’s economic evaluation stands out for its honest assessment of business cases.
Rather than promising universal savings, the document acknowledges that benefits vary significantly based on context, ranging from cost-neutral to 33% savings depending on baseline conditions and deployment strategies. This candor, combined with frameworks for evaluating total cost of ownership, helps organizations set realistic expectations and structure appropriate business cases.
The discussion of organizational change management and training requirements (Section 6.3.4) addresses often-overlooked human factors. The recognition that digital substations require fundamentally different skill sets combining traditional protection engineering with IT and telecommunications expertise is crucial for successful implementation.
The brochure’s recommendations (Chapter 11) distill complex experience into actionable guidance. Emphasis on top-down engineering approaches using System Configuration Language (SCL) files, implementation of standardized PACS solutions, and proper cyber security frameworks provide clear direction for utilities developing deployment strategies. The honest discussion of interoperability challenges and ongoing standardization needs sets appropriate expectations while highlighting areas requiring continued industry attention.
While cyber security receives coverage (Section 6.3.5), the rapidly evolving threat landscape means this area may require frequent supplementation. The brochure acknowledges this limitation appropriately, positioning cyber security as an ongoing concern rather than a solved problem.
CIGRE Technical Brochure 949 successfully achieves its stated objective: providing comprehensive guidance for implementing process bus technology in protection, automation, and control systems. Its balanced perspective – acknowledging both significant benefits and real challenges – distinguishes it from promotional literature while maintaining an appropriately optimistic outlook on the technology’s potential.
For utilities contemplating digital substation deployment, system integrators designing solutions, or equipment manufacturers developing compliant products, this document offers essential reading. The recommendation that “utilities should embrace this technology and take advantage of the associated benefits” is well-supported by evidence while remaining appropriately cautious about implementation complexity.
This brochure represents CIGRE at its best: facilitating knowledge transfer through rigorous, impartial technical documentation that advances the entire industry. It will undoubtedly serve as a foundational reference for years to come as the power industry continues its digital transformation journey.
