Insulated cables

100 years of an idea

CIGRE celebrated in 2021 its Centennial Anniversary, since the first Session was held in Paris in 1921. Study Committee B1 is proudly finding its seeds in that event, with a discussion under the heading "construction of lines" and the sub heading "underground and submarine lines".
Six years later, in year 1927, it was founded a specific Study Committee dealing with Power Cables that was initially designed as SC 2, then evolved to SC 21 and finally changed to SC B1 with the name of “Insulated cables”.

In 1921 CIGRE discussed about “utilization limits of single and mufti core cables for AC and DC, determination of electric constants, after-laying tests”.
Over the years this developed in a more structured and wide coverage of related topics. After a century since then, the field of activities of SC B1 concerns the development and operation of all types of AC and DC insulated cable systems for land and submarine power distribution and transmission applications. The main focus of SC B1 remain on high voltage (HV) and extra high voltage (EHV) transmission applications, but with a remarkable attention to distribution and smart grids medium voltage (MV) cable system applications.
Within this field, the scope of work of SC B1 covers theory, design, applications, manufacture, installation, testing, operation, maintenance, end of life and diagnostic techniques of insulated cable systems.

A good structure is of essence to deal with this extensive scope. Study Committee B1 is maintaining a suitable organization to cover all associated aspects.

SC B1 has therefore a Chairman (Marco Marelli, IT), a Secretary (Matthieu Cabau, FR) and – at the end of 2021 – a composition of 24 Regular Members, 13 Observer Members and 6 Additional Members that are bringing additional competences to the traditional “power transmission” background of most of Members.

The structure of CIGRE SC B1, the long term plans, the continuous addition of new energetic people, are supporting the progress in the daily work together with the four pillars that help to address the work within the “Insulated Cables” community:

• Empowerment of individuals in their contribution to Working Bodies, where they represent their respective Countries.
• Efficiency and Quality, with tough targets on the time-to-market of the works of WGs.
• Team spirit, to enjoy the unique international network of people and to have fun while working.
• Communication and local presence, encouraging all people to be ambassadors of B1 in local and international events.

The technical work is done through Working Groups. Each year, new Working Groups are launched to address the need coming from stakeholders.
The new work items are normally decided during the Annual Study Committee Meeting. Following decision of the Study Committee the Terms of Reference (ToR) are most often prepared by Task Forces.
The proposals of New Work Items submitted to the Study Committee are prepared by the Customer Advisory Group (CAG) and formally established by the Strategic Advisory Group (SAG) of the Study Committee. Each Region of the world is represented in the CAG to gather the needs of the Regional Target Groups. Also the contribution of individuals is important to identify the needs of the Target Groups of the Study Committee, this can be done by sending ideas for new works to the SC through the national representative or via CAG at cigre.scb1.cag(@)gmail.com.
The work of Study Committee SC B1 is also kept tuned with IEC, IEEE, and other interest groups, as well as with Local and Regional CIGRE organizations.

The dissemination of outcome of SC B1 works is mostly done through a Tutorial and Publication Advisory Group (TAG) that was installed in SC B1 with the scope to implement CIGRE TC's suggestion, that "Study Committees have to deal with education, continuous training, tutorials and publications". The B1 TAG is the working body within SC B1 to coordinate all activities in this field.

What happened in 2021

Before to mention any of the activities performed, any thought about 2021 starts with the sad news that reached the Study Committee that lost one of its active members. Paolo Maioli (IT) passed away on March 31st, 2021, after his health worsened rapidly. His dedication to CIGRE that he supported as WG member, WG convener and lately as SC B1 Italian Member was the reflection of his passion for science and technologies. This was second to his Faith, to his integrity and to the friendship that he shared with all those who had the fortune to know him. His memory remains in our thoughts and prayers.

The most important event for Study Committee B1has been the active participation to the Virtual Centennial Session. The event has been for SC B1 an active and lively forum of international experts, successful even with the “virtual” format.

The prepared contributions and the subsequent discussions were based on the 47 papers prepared for the 2020 Session and the 15 questions of the 2021 Special Report. In addition there have been:

• Three contributions from a Next Generation Network representative giving a diverse and future-oriented viewpoint on the topics under discussion
• A contribution titled “Impact of Hydrogen developments on cable system” to help SC B1 to enlarge horizons and to prepare for future possible developments
• A presentation on History of SC B1 aimed to celebrate the 100th anniversary of CIGRE

As part of the Virtual Centennial Session program, one tutorial was presented by SC B1. The presentation investigated many aspects of installation of HV and EHV cables, both land and submarine. Traditionally tutorials are based on finished Technical Brochures, but this topic has a very high interest and the decision was then to base the presentation also on ongoing work thus including material from WGs B1.61 and B1.65 as well as B1.41 that already published TB 714.

The Annual Study Committee B1 Meeting was very dense and fruitful. Future works agreed in the SC meeting and to be approved by Technical Council Chair are very much aligned with the E2E vision of CIGRE, with the attention to sustainability, with the cooperation with IEC, with the support committed for a more reliable and modern transmission network.
Before closing the SC Meeting, nearly at the end of the Virtual Centennial Session, the Chairman thanked the Secretary, the Special Reporter, all people who supported the GDM (panelists, NGN rep, interaction managers, invited speakers), all SC Members, conveners, experts, ex-officers, and the Central Office for the preparation and the organization of these successful events.
Both the Group Discussion Meeting and the Annual SC B1 meeting concluded with the warm wish to meet safely and in person soon.

Celebrating people

Celebration of CIGRE Awards took place during the Virtual Centennial Session.

For Study Committee B1 this has been first of all the occasion to thank the people who significantly contributed to the success of previous year event. Indeed the “CIGRE Pioneer e-session Achievement Award” is a special award created to recognise the outstanding efforts of the SC members who contributed to the achievement of the 2020 e-session.
Awards for B1 “Insulated cables” have been granted to: Andre Cuppen (NZ), Jon Vail (GB), Russell Wheatland (AU), Frank de Wild (NL), Carla Damasceno (BR), Søren Mikkelsen (DK), Marc Jeroense (SE), Christian Jensen (DK), Pierre Mirebeau (FR).
The pandemic period has been supported with dedication and passion by many people and beside those who has been named, many others deserve a big “thanks” for their support.

Technical activities

As mentioned, the Study Committee Meeting that happened in conjunction with the 2021 Virtual Centennial Session was the occasion to launch new working groups and new activities according to defined procedures.

Based on suggestions collected in first half of 2021, the following WGs were therefore discussed and launched during the SC B1 meeting:

WG B1.82 - MVDC Cable System Requirements

The rapid development of distributed renewable energy resources (DERs), associated with the fast growth of DC power generation and DC loads, made Medium Voltage Direct Current (MVDC) grids to be considered. As such development occurs, it will be necessary to establish a common, trans-industry approach dedicated to ensuring MVDC cable technology offers the same performance, interoperability and reliability guarantees as experienced in other cable applications, without over-specifying requirements as if they were for HVDC use. The WG will explore experiences and applications, consider system requirements and existing standards, propose recommendations for design, operations and maintenance of MVDC cable systems.

WG B1.83 - Grounding aspects for HVDC land cable connections

The use of HVDC links has been increasing recently and especially long underground ones. However unlike for HVAC links, there is few literature and guidelines which specifies or recommends how to properly ground this kind of system. HVDC grounding is made to ensure safety aspects, cable system integrity, easier fault finding. These 3 aspects are taken into account when designing the grounding system of a HVDC land cable connection. The WG will study different current practices and will recommend the more suitable grounding designs.

WG B1.86 - Assessment, Prevention and Mitigation of Safety Risk in Cable Systems

Working group B1.71 evaluated all documents published by SC B1 (TB, Electra, Special Reports, etc.) and detected and understood the potential hazards and the related safety risks in cable systems. Also gaps in existing CIGRE documents were identified. Conclusions were reported in CIGRE Newsletter “Future Connections” in May 2021 and formed the bases for WG B1.86. The result of this work will include generic methods and best practices to avoid or to mitigate all identified safety risks during all lifetime phases for both underground and subsea cables. Content of the future technical brochure will not substitute the provisions specified by local administrations and authorities, and national/international health and safety guidelines and legislations.

WG B1.87 - Finite Element Analysis for Cable Rating Calculations

Technical Report IEC TR 62095 was written at a time when Finite Elements studies were undertaken only by a small group of experienced analysis engineers. Nowadays user-friendly software tools are widely available, and standard laptop computers can solve complicated models. It is now increasingly common to have rating studies being performed using FE, most notably in situations where IEC 60287 does not easily allow the problem to be solved. Number of users solving cable ratings via FE is much higher, and their specific experience is (on average) less than would have been the case 15 years ago. On this basis, the type of guidance needed is now different to that offered by IEC TR 62095. While much of the information contained there is still valid, there are many gaps which could be filled by new work from CIGRE.  The WG will develop guidance for ‘purchasers’ on how to correctly specify FE modelling for cable rating purposes, provide guidance to FE users on when FE is needed and the correct models to be used, provide worked examples.

Beside these four Working Groups, two other ones were decided but agreed to be postponed and launched during 2022. They are about:

• Cyclic and Emergency Current Rating Calculations, with the aim to support IEC and to give guidance for a possible update of IEC 60853
• Cable Systems Electrical Characteristics, with the aim to produce an updated version of the Technical Brochure 531

One important decision was taken on how to manage the future issues of documents on “Update of service experience of HV underground and submarine cable systems”. Publication of TB 815 followed the traditional cycle of 10 years between updates. Task Force TF B1.81 worked on how to produce statistics every 2 years and proposed to set an Advisory Group in 2022 to handle those statistics.

In addition to the described new Working Groups, during the web-meeting, Study Committee B1 decided to launch preparatory Task Forces to evaluate the need for future Working Groups on the following subjects:

• TF B1.88 : “Non-SF6 GIS terminations”
• TF B1.89 : “Guidance for conducting cable systems failure analysis”

These Task Forces will give their outcomes to the Study Committee Meeting in 2022 and – in case they will recommend launching working groups – they will propose respective Terms of Reference.

With the decisions taken during the SC B1 meeting and the subsequent approval from CIGRE Technical Council, by the end of 2021 SC B1 can count on 3 Advisory Groups, 18 Working Groups, 5 Joint Working Groups and 3 Task Forces. Also, B1 participates in several WGs or JWGs led by other SCs.

This massive work is possible thanks to the many people being involved. At end of 2021 383 different experts are working in SC B1 leading to 474 contributions in the various working bodies including SC membership. Among them, 78 are young WG Members (under 35, Next Generation Network), covering a total of 95 positions and marking a +25% compared to past year.

Spreading the knowledge

Year 2021 marked also a significant set of achievements on the dissemination of work done within the Study Committee.

Four Technical Brochures have been published as result of completed works and a fifth one was published early in 2022:

It is worth noting that they are covering topics that are of extreme interest and – from various perspectives – are supporting the sustainability of cable systems and their role in the energy transition.

Other important publications from SC B1 include:

• The article “Safety: a crucial issue to sustainability on insulated cable systems” reporting the work done by WG B1.71 and published in the newsletter “CIGRE Future Connections” in May 2021, and ELECTRA in June 2021.

The commitment of SC B1 to communication extended to tutorials and webinars. In six occasions experts who often were conveners or leading people of past Working Groups, delivered interesting presentations that were broadcasted and thus able to reach a global audience.

CIGRE Webinars, also available on e-cigre website:

Tutorial at CIGRE Virtual Centennial Session:

• “Installation of HV/EHV cable links” – Aug 27, 2021 (available in the package of the Session - SC B1 documents and videos on e-cigre)

Tutorial at CIGRE Symposium Ljubljana:

• “Implementation of Long AC HV and EHV cable systems” – Nov 21, 2021

Tutorial at Jicable HVDC 2021 Conference:

• “Two new recommendations for testing Extruded and lapped insulated HVDC & EHVDC cable systems at a rated voltage up to 800 kV” – Nov 8, 2021

Finally, since August 2021 the SC B1 new public website is fully live. It includes documents and information to know more about scope and activities of Study Committee and Working Bodies and how to interact with the SC.
This is an important step to better disseminate information on works done, but also on the organization and the planned activities.

Looking forward

After two years of meetings in electronic or virtual format, it is expected to return in 2022 to have the General Session in Paris. In presence.

The program for Study Committee B1 includes:

• A workshop on Monday 29th August in the afternoon, about “Extra-long transnational transmission lines” jointly organized by Study Committees B1, B2, B4, C1. The Workshop is intended to focus on the technical and power system challenges, solutions and problems as well as on future developments. Another aspect is to get an overview on progress initiatives related to global networks.
• A tutorial on Tuesday 30th August in the morning. This will be titled “A new era for submarine cables” and will touch on the work done by various CIGRE B1 working groups on the different applications and the different challenges of submarine cables. The subject is very much aligned with the evolution of the electrical network associated to the ongoing and upcoming energy transition, which includes more interconnectors, installation in deeper waters, use of dynamic cables for offshore floating wind generation.
• The Poster Session on Tuesday 30th August in the afternoon. This is a unique occasion to meet the authors papers accepted for the Session. The technical content and the quality of papers is expected to be excellent, both because the 2022 Session was long expected and many people targeted CIGRE to publish their achievements and because of the huge and excellent work performed by a team of senior reviewers.
• The Group Discussion Meeting taking place the full day on Wednesday 31st August, with live discussion about the topics described in the Preferential Subjects. This meeting will be guided by the questions coming from the Report prepared by a team of four Special Reporters, and it is expected to attract contributions about learnings from experiences, new and future functionalities and applications for cable systems, their contribution to sustainability.

The Annual SC B1 Meeting, happening in the same week, will again be the occasion for SC Members to review the work in progress and to start new activities in alignment with the objectives and the targets set in the Strategic Plan and shaped by CIGRE technical directions.

This year will be also a year of changes, with a significant number of members of the Study Committee that will be changed in the normal rotation happening every two year. The “thanks” to outgoing people and the “welcome” to incoming members are words that only partially reflect the gratitude for the work done by fantastic individual in representation and support of their countries, and the high expectation on the people who are this year joining the SC.
The same is valid for the chairperson, as Marco Marelli (IT) will reach the end of his term at the end of the 2022 Session and will be replaced by Geir Clasen (NO).

These changes will confirm and refresh the essence of the Study Committee B1 “Insulated Cables” that is about a technical community capable of balancing rootedness in history with a constant attention to the evolution of the electrical system, with the ability to renew itself in the structures and relationships to better serve evolving stakeholders.

Contact

• Contact of the Chair and/or the Secretary of the Study Committee