study committee b1 insulated cables 2014 -...

Action Plan SC B1 2014-2017 Last version 1/41 PA/AG: 2015-07-15

CONSEIL INTERNATIONAL DES GRANDS RÉSEAUX ÉLECTRIQUES INTERNATIONAL COUNCIL ON LARGE ELECTRIC SYSTEMS

STUDY COMMITTEE B1

INSULATED CABLES

2014 - 2017 ACTION PLAN

JULY 2015


Table of Contents

1 FRAMEWORK .............................................................................................................................. 3

2 TECHNICAL PLAN ....................................................................................................................... 3

2.1 SC ADVISORY GROUPS .............................................................................................................. 3 2.2 SC WORKING GROUPS ............................................................................................................... 4 2.3 SC TASK FORCES .................................................................................................................... 10 2.4 INTERACTIONS WITH OTHER CIGRE COMMITTEES ..................................................................... 10 2.5 INTERACTIONS WITH OTHER ORGANIZATIONS ............................................................................. 11 2.6 SYMPOSIA AND COLLOQUIA ...................................................................................................... 11

3 ADMINISTRATIVE PLAN ........................................................................................................... 12

3.1 SC B1 MEETINGS .................................................................................................................... 12 3.2 RECORDS OF SC B1 MEETINGS ................................................................................................ 12 3.3 NEW SC B1 WGS AND TFS ...................................................................................................... 12 3.4 PROGRESS OF SC B1 WGS AND TFS ....................................................................................... 12 3.5 SC B1 PUBLICATIONS .............................................................................................................. 12 3.6 TUTORIALS............................................................................................................................... 13 3.7 SC B1 WEB SITE ..................................................................................................................... 13

APPENDIX I: ADVISORY GROUP, WORKING GROUP AND TASK FORCE FORMS (DEC 2013) .. 15


1 FRAMEWORK

The purpose of the three years Action Plan is to outline the main technical and administrative activities that SC B1 expects to carry out in the specified time frame of 2014 through 2017.

It takes into consideration the TC Action Plan as well as the SC B1 2008-2018 Strategic Plan, with which it is in line, as well as specific proposals put forward by Members during Study Committee meetings.

2 TECHNICAL PLAN

This part of the Action Plan summarizes the technical activities, which are currently in progress (N.B. new technical activities consistent with the SC B1 Strategic Plan may be initiated during the validity period of this Action Plan). The terms of reference of SC B1 AGs, WGs (all duly approved by TC Chairman) and

TFs can be found in Appendix I. A one page chart showing all the CIGRE WGs, JWGs, TFs and JTFs in which SC B1 is currently involved is also provided.

2.1 SC Advisory Groups

SC B1 has four installed Advisory Groups (AGs), to deal with strategically important work. They were disbanded in 2010 following a Technical Committee decision which considers that AGs are disbanded at the end of the term of office of the outgoing Chairman. They were re-installed by the incoming Chairman who modified the terms of reference of the TAG and installed the PAG.

- The SC B1 Strategic Advisory Group SAG under the Convenership of the Chairman is an AG with the task to analyse items of fundamental importance and to support the Chairman with preparing strategic decisions. The SAG typically meets once a year.

- The SC B1 Customer Advisory Group CAG is an AG with the task to ensure that the needs of the Target Groups are addressed within the work of SC B1. It will co-ordinate all activities in this field and work in close contact with the SC Chairman and the Strategic Advisory Group B1-SAG. The CAG will present its results and recommendations prior to any external action to the B1-SAG, for approval. The Convener of the CAG is also a member of the SAG.

- The SC B1 Tutorial and Publication Advisory Group TAG is an AG with the Scope to implement SC B1’s high ambitions for education, continuous training, tutorials and publications. The B1-TAG will be the working body within SC B1 to co-ordinate all activities in this field. It will work in close contact with the EPEE, the SC Chairman, the Strategic Advisory Group B1-SAG and the Customer Advisory Group B1-CAG. It will involve all SC B1 Members and Conveners as contacts. The Convener of the TAG is also a member of the SAG.


- The SC B1 Prospective Advisory Group PAG is an AG with the task to look the emerging techniques and technologies to help SC B1 to detect the early needs of the cable industry and to help SC B1 to launch the necessary WGs at the right time. The Convener of the PAG is also a member of the SAG.

2.2 SC Working Groups

SC B1 disbanded two WGs in 2015 after their work was published:

JWG B1/B3.33: Feasibility of a common, dry type interface for GIS and Power cables of 52 kV and above

WG B1.40: Offshore generation cable connections.

SC B1 disbanded also one WG in 2015 waiting for new ToR:

WG B1.39: On shore generation cable connections (to the grid)

At the end of June 2015, SC B1 has now 5 WGs finalizing their work and 12 WGs

and 1 JWG in progress: WG finalizing their work:

WG B1.28: On site Partial Discharges Assessment WG B1.28 was set up in 2008 with Nigel Hampton (US) as Convener and is due to present its final report in 2011. Due to availability problems, it was decided in accordance with Nigel Hampton to change the Convener to Mark Fenger (CA). The final report was circulated to SC B1 Members for final approval. The Technical Brochure will be published in 2015.

WG B1.34: Mechanical forces in large cross section cable systems

There are no special “bad” experiences with “large conductors”, but the trend is going to larger and larger cross sections. It was identified through SCB1 target groups that a technical guide can reduce risk of poor design and installation. The work will be limited to polymeric cables, but should study all types of sheaths and the different installation arrangements such as rigid, flexible, transition from ducts to rigid installations, installation in tunnels, and shafts …

WG B1.34 was set up in 2010 to study this specific topic with Johannes Kaumanns (DE) as Convener and the final report for publication is expected at the end of 2015.

WG B1.35: Cable rating Cable ratings are generally determined by using IEC standards such as IEC 60287 and IEC 60853, but these documents do not cover all situations. As examples, HVDC cables, deep burial, horizontal drilling, multiple circuits are currently not included in these standards though these situations are more and more faced. This work is made in close cooperation of IEC TC 20 WG 19. It will take into account the crossings between cables and other heat sources and the temporary ratings.


WG B1.35 was set up in 2010 to study this specific topic with Frank de Wild (NL) as Convener and the final report for publication is expected in August 2015.

• WG B1.42: Testing of Transition Joints Between HVDC Cables with

Lapped and Extruded Insulation up to 500 kV

Although the extruded HVDC cable technology is developing very fast, lapped HVDC cables will still be on the market for many years. There are projects that consider massimpregnated cables for the submarine part of the route and extruded cables for the land part of the route. There is a need to define test specifications for how to qualify transition joints between these two technologies. WG B1.44 was set up in 2012 to study this specific topic with Gunnar Evenset (NO) as Convener and the final report has been published in June 2015.

WG B1.43: Mechanical Testing of Submarine cables Update of mechanical tests for submarine cables is needed since submarine cable installations are growing for higher powers and new applications (wind farm connections, dynamic power cables and deeper sea installations, …). Based on a proposal prepared by WG B1.27, WG B1.43 was set up in 2012 to study this specific topic with Marc Jeroense (SE) as Convener. the final report has been published in June 2015.

JWG and WGs in progress

WG B1.36: Life cycle assessment and environmental impact of underground cable systems

Different High Voltage Cable types as well as their associated civil works and installation techniques do not impact the environment in the same way. In order to minimize such impact, it is important to develop the necessary tools that would enable the engineers and the decision makers to compare the Global Environmental Impact of different underground cable systems over their whole life cycle (including end of life and disposal). A few methods have been devised by electric utilities to assess the environmental impact of Underground High Voltage Systems over their life cycle. A Task Force named TF B1.36 was set up in 2009 to study this specific topic with Ray Awad (CA) as Convener and was due to present its considerations whether or not to install a full WG on this issue in 2010. As the proposal was not mature enough, the Chairman decided to extend the TF for one more year. WG B1.36 was finally set up in 2011 with Aude Laurens (FR) as Convener and the report for circulation among members is expected in 2015.

WG B1.37: Guide operation of fluid filled cable systems The paper cables are very reliable and should continue their service as long as possible. The present risk is to see the cable suppliers leaving the field, without anybody able to repair the existing cable circuits. The Working Group will produce a brochure recommending guidelines on the best practices for the continued operation of self-contained fluid filled cable systems. The WG will


address the technical aspects on the continued operation of these cables such as: recommended maintenance, testing (routine and after repair), refurbishment and modifications for improved performance, operational availability and constraints, fault repairs, oil system capacity reviews, fluid monitoring and analysis, leak location techniques and a cable and accessories suppliers list. The scope will exclude pipe type cables. It will cover AC and DC land and submarine cables which have in principle the same problems. The voltage range is from EHV to distribution levels. WG B1.37 was set up in 2010 to study this specific topic with Colin Peacock (AU) as Convener. Due to availability problems the WG had to be re-launched after the 2011 SC B1 meeting. The final report is expected at the beginning of 2016.

WF B1.38: After laying tests on AC and DC cable systems with new techniques.

Extruded insulation is rapidly becoming the insulation of choice in both new and replacement transmission class cable circuits. While the cable and accessories are tested in the factory, the workmanship to install the accessories can only be tested after the installation has been completed and before the cable system is put into service. As DC testing, commonly used for FF cables, is not efficient for XLPE cables for AC transmission systems, attention has to be focussed on AC testing methods. The testing of DC cable systems will also be addressed to define which technology is the most appropriate. In the past, test equipment capable of testing long lengths of cables were not available so that a soak test at operating voltage for 24 hours was carried out by connecting the cable to the power system. In the last ten years different power sources have been developed that have the power rating to test long cable lengths. These include AC resonant power supplies, damped AC (DAC) and, more recently, very low frequency (VLF). In addition, there have been significant improvements in diagnostic tools such as off-line PD and dissipation factor measurement to assess the condition of a cable system. However, as there are presently only withstand test levels given in IEC 60840 and 62067 for AC resonant test voltages, there is a need to establish test voltage levels for other voltage sources and also establish suitable diagnostic tests. WG B1.38 was set up in 2011 to study this specific topic with Mark Fenger (CA) as Convener and the final report is expected in 2016.

WG B1.41: Long term performance of soil and backfill of cable systems Existing and up-rated cable systems are loaded increasingly higher. This can be driven particularly by real time rating systems and by re-conductored systems with new high stress dielectrics permitting larger conductor sizes within the same duct or pipe. In all cases the higher loads result in higher operating temperatures for the backfill even if the rated operating temperatures remain the same. The higher loads will increase the cable/duct to soil interface temperatures that will impact the external thermal environment of the backfill and native soil. Depending on the aged backfill and soil condition, this can severely limit the potential capability of the technological advances.


Many of the existing circuits have been in service for 40 or more years when engineered backfills were in their infancy. Limited knowledge is available of past backfill design and how it will change over time. Recent work showed that properties have changed, such as degree of compaction and stratification of backfill components. Reason for the changed physical backfill conditions could be road vibration, ground water movement or settling. WG B1.41 was set up in 2012 to study this specific topic with Walter Zenger (US) as Convener and the final report is expected in 2016.

WG B1.44: Guidelines for safe work on cable systems under induced voltages or currents

During several phases of a cable system life (installation/maintenance/testing/ upgrading/removal), it can be necessary to work under induced voltages or induced currents:

- During the pulling or the laying of a cable in the vicinity of an energized system:

- underground cable or overhead line - During the jointing operations in the installation process - When checking or maintaining link boxes - During the repair of the cable after fault - When removing the cable for disposal at the end of its life.

WG B1.44 was directly set up in 2012 to study this specific topic with Caroline Bradley (UK) as Convener and the final report is expected in 2016.

WG B1.45: Thermal monitoring of cable circuits and grid operators’ use of dynamic rating systems

Nowadays, due to a more variable situation and increasing loads in the power grids, a dynamic rating system and other measurement values aid the asset manager in making optimal decisions in planning investments in the High Voltage grid. Based on measurement a grid operator can on the one hand decide if a hotspot in network should be taken away to increase the capacity or if the hotspot should be managed with the dynamic rating system and on the other hand will know the load and overload possibilities in real time and for the coming hours. WG B1.45 was set up in 2013 to study this specific topic with Blandine Hennuy (BE) as Convener and the final report is expected in 2016.

WG B1.46: Conductor Connectors: Mechanical and Electrical Tests Current IEC 61238-1 standard applies to connectors for medium voltage cables. There is no IEC standard for connectors for HV cables. The procedures from IEC 61238-1 along with manufacturer and user specifications have been used to type test HV cable connectors. The thermal, mechanical and resistance stability tests specified in current standard are applicable to HV but some requirements are specific to high voltage applications. These include dimensional and functional requirements of connectors within HV cable accessories, typically larger cable sizes, versatility of the conductor constructions as well as different circuit load patterns, short circuit levels and mechanical stresses due to tensile and thrust loads.


The IEC WG16 of the TC20 commenced work on revision of current IEC61238-1 standard. During this work, some members of WG16, expressed interest that the scope of this standard is extended to high voltage cable application. The TF in charge of the revision believes this work needs to be done by a dedicated group of high voltage experts. At the Study Committee B1 meeting held in Paris on August 28 and 29 2012 it was agreed that a task force be established to consider if further guidance was needed on the testing of connectors for HV cable accessories. It was also decided during the meeting that the topics should be expended to cover mechanical loads, (not only thermal), to include all connectors (mechanical and other types) and to include termination and joints connectors. WG B1.46 was set up in 2013 to study this specific topic with Milan Uzelac (US) as Convener and the final report is expected in 2016.

WG B1.47: Implementation of Long AC HV & EHV Cable Systems The power transmission network has been developed during the last decades based on the use of overhead lines. EHV underground cables systems have been available since a long time, but their development has been limited by large capacitance and dielectric losses as well as relatively low current rating compared to OHL. However with the use of new materials and processing technology the situation has changed significantly, so that the constraints on maximum length and power transfer have been largely overcome. The difficulties in installing new overhead lines are making it essential to consider the use of longer underground cables links, as demonstrated by the increasing number of long underground projects. There are still however technical challenges to consider whilst planning new cable installations. The most sensitive topics are those concerning reliability, impact on the transmission grid and installation. Excellent work has been done by Cigre Working Group C4.502, “Power System Technical Performance Issues Related to the Application of Long HVAC Cables”. The WG proposes the following definition of long length of HVAC cables for this topic:- “A long length of insulated cable is one where the load due to the capacitive current (at power frequencies cables behave as capacitors therefore they generate reactive power) needs to be taken into account in the system design. Typically this would be 40 km for voltages less than 220 kV and 20 km for 220 kV or greater”. WG B1.47 was set up in 2013 to study this specific topic with Ken Barber (AU) as Convener and the final report is expected in 2016.

WG B1.48: Trenchless technologies for Underground Cables In October 2001 Technical Brochure 194 was published, describing “Construction, laying and installation techniques for extruded and self-contained fluid filled cable systems”. The Technical Brochure included a brief description of innovative techniques including horizontal drilling, pipe jacking and micro-tunneling. TB 194 describes the techniques, their limitations and the changes in cable design necessary to make use of each technique (for


example, the changes needed in order to match the ampacity of a shallow, direct buried installation). Although much of the information on trenchless cable installation in TB 194 is still valid, it is relatively brief and few practical examples are given. There is increasing pressure to underground transmission circuits and it is becoming more common for a length of underground cable to be introduced into an overhead line circuit. There is also increasing pressure to reduce the cost of undergrounding and reduce the disruption (e.g. to traffic flow) caused when underground circuits are installed. A number of significant technical changes to underground cable circuits have been seen since TB 194 was written; for example, extruded cable has almost completely superseded fluid filled cable for new installations, delivery lengths for land cable have increased and there is a trend towards larger conductor sizes. There has been a large increase in the use of cable in sensitive habitats (e.g. shore landings for AC cable from offshore wind farms and DC cable interconnectors). In some cases the landing sites of submarine cables have been contaminated by prior use. Trenchless technologies do not disturb such sensitive areas and have been used in these applications. In addition to changes in cable technology and attitudes to undergrounding, there have been technical advances in the methods used for trenchless installation since TB 194 was written. WG B1.48 was set up in 2013 to study this specific topic with Eugene Bergin (IE) as Convener and the final report is expected in 2017.

JWG B1/B3.49: Standard design of a common, dry type plug-in interface for GIS and power cables up to 145 kV Taking into account the market trend in some countries towards a commoditization of the High Voltage cables lower or equal to 145kV, the working group B1-B3.33 had concluded that there is room in these voltage levels for a standard design in parallel with the present designs. JWG B1/B3.49 was set up in 2013 to study this specific topic with Pierre Mirebeau (FR) as Convener and the final report is expected in 2017.

WG B1.50: SVL and bonding systems (design, testing, operation and monitoring)

The basic information needed to design a bonding system is included in several documents such as Electra 128-1990, TB 283-2005, and TB 347-2008. Some of these documents need to be updated. In addition it is noted that cable bonding components and related national regulations have changed in recent years. The WG plans to address related issues with sheath voltage limiters (SVLs) and bonding systems. WG B1.50 was set up in 2014 to study this specific topic with Tieban Zhao (US) as Convener and the final report is expected in 2017.

WG B1.51: Fire issues for cable installed in air

A significant concern is the fire safety of insulated cables installed in air, since it is often not practical for fire protection services to give a rapid response in case of fire. This subject has been raised in the Technical Brochure 403


“Cables Systems in multipurpose or shared structures”. Whilst it is possible to bury some of the more hazardous cables in the floor of the tunnel, provide protection barriers or install fire protection systems such as water sprays or other devices, these systems are all expensive. It was therefore important to establish if more suitable cable designs could provide an adequate level of fire protection without the need for separate protection systems. Quite often tunnels are “ventilated” with certain airflow, having an incremental effect on some of the typical fire behavior of cables, including fire propagation, development of smoke and to a lesser extend development of corrosive fumes Standardizing work was done by IEC, but in terms of fire behavior these standards, at present, are mainly applicable to low voltage cables. More recent developments of new designs and requirements of power cable systems in terms of flame retardant properties are not yet considered; for this reason it is difficult to apply the above mentioned standards to transmission and distribution. WG B1.51 was set up in 2014 to study this specific topic with Paolo Maioli (IT) as Convener and the final report is expected in 2017.

WG B1.52: Fault location on land and submarine links (AC and DC)

The increasing number of land and submarine cable assets globally has created a focus on cable fault location capabilities. All faults in cable systems are different and cable fault location depends to a great extent on applying the appropriate technique or combination of techniques. The methods for locating power cable faults require competent engineers and service providers. Guidance is therefore required for engineers on the correct application of the various techniques available.

WG B1.52 was set up in 2014 to study this specific topic with Robert Donaghy (IE) as Convener and the final report is expected in 2017.

2.3 SC Task Forces

SC B1 currently has one TF whose task is to define the terms of reference of potential new WGs. Their reports are due for the next meeting of SC B1 in September 2015 for decision for future work.

TF B1.54: Behavior of cable systems under large disturbances

(earthquake, storm, flood, fire, landslide, climate change) with Harry

Orton (CA) as Convener

2.4 Interactions with other CIGRE Committees

Relations with interfacing Study Committees SC B1 strives to have good cooperative spirit with the neighbouring SCs, and to set up JWGs whenever dealing with technical issues interfacing with cables, or other technical topics with mutual interest. The committees with the more traditional interfaces are B2, B3 and D1, but B4, C3, C4, C6 are also important partners. SAG members have to liaise and to disseminate the information and collect the needs of the other SCs or organization.


SC B2 S. Swingler SC C6 M. Marelli

SC B3 P. Argaut SC D1 W. Boone

SC B4 C. Jensen AORC K. Barber

SC C3 E. Bergin ICC W. Zenger

SC C4 J. Karlstrand IEC P. Mirebeau

Jicable A. Gille

Relations with AORC and other Regional Forum SC B1 strives to actively take part in AORC meetings. These are seen as alternatives for Asian and Pacific B1 members not being able to attend the meetings more far away. SC B1 have the same policy when other similar regional meetings are arranged.

2.5 Interactions with other Organizations

After due considerations, SC B1 is open to interact with any other organisation in the field of insulated cable when this is beneficial to both parties. In the future, this will be evaluated before any decision is drawn on similar interactions.

Interactions between CIGRE SC B1 and IEEE/PES Insulated Conductors

Committee ICC A permanent JTF SC B1/ICC is operational with Walter Zenger (US) as Convener. Moreover, a much appreciated Joint Discussion Group was launched by ICC and SC B1 regularly contributes. B1 will strive to maintain the good relation with ICC, to get a vital and natural link to the North American cable society.

Interactions between CIGRE SC B1 and IEC TC20 The relations between the two Committees are mainly informal, but are also very intensive. The Chairmen (or as appointed) are invited to the other’s annual meetings. Specific cooperation (on coming test standards) is desirable. In this prospect, a member of SAG (Pierre Mirebeau) is acting as liaison officer. In some cases, IEC TC 20 is asking for some work to help them in the elaboration of new or revised standards.

Relations between CIGRE SC B1 and CIRED SC B1 will analyse its field of activity with regard to issues which might be of common interest with CIRED and will communicate with CIRED about mutual information, coordination and possible cooperation whenever deemed appropriate. The TOR of WG approved by the TC Chairman mention if the work is relevant for MV or LV cable systems.

2.6 Symposia and Colloquia SC B1 plans to participate in joint Symposia and Colloquia wherever appropriate.

In 2015, SC B1 participated in Jicable 2015 (June 21-25 2015, Versailles, France)

and in a symposium entitled Development of Power Systems and international

integration of operation and markets (May 27-28 2015 Lund, Sweden) led by SC B4, C1 and C5. Other participations are already scheduled in 2015 and 2016.


3 ADMINISTRATIVE PLAN

This part of the Action Plan summarizes the main administrative actions envisaged by SC B1. Said actions are essentially aimed at securing a wider participation in the SC, increasing its operational efficiency and enhancing the visibility of its activities.

3.1 SC B1 Meetings

In uneven years, all Members are asked to prepare brief presentations of the main events, which had occurred during the past two years in their respective countries in the field of insulated power cable systems. In addition, Members shall identify the main target groups in their countries and consider means how to approach them for mapping their needs and degree of satisfaction with our work. SC Members shall function as interfaces to their local target groups.

3.2 Records of SC B1 Meetings The Decision List of SC Meetings is a very positive action oriented tool. It is issued immediately after the Meetings (within one week).

The Official Minutes of SC Meetings remain however important for record purposes. Their publication takes place no later than two months after the Meetings.

3.3 New SC B1 WGs and TFs The "starting transient" of new WGs and TFs will continuously be emphasized. Most technical activities of WG or TF shall start no later than three to four months after said WG or TF have been set up. Members, who indicated during SC B1 meetings that experts from their respective countries will participate in a new WG or TF, have been advised that the associated nomination must be finalized and communicated directly to the relevant Convener, with copies to the Chairman and Secretary, within a maximum of three months. This aspect will be followed up closely in the future, too. National members are asked to be attentive to the appointment of WG experts (competence, active participation, organization of meetings). No marketing will be tolerated. It is planned to ask that all members of WGs sign a paper in which they undertake not to make attempts for commercialisation.

3.4 Progress of SC B1 WGs and TFs Conveners are asked halfway between SC B1 Annual Meetings to provide a short formal update on the progress of their respective WGs and TFs (one page report to be sent to the Chairman and the Secretary by the end of February of each year). It was recently noticed that some WGs did not honour the deadline which was given in the ToRs. SC B1 will concentrate its efforts on producing their reports within the specified deadlines.

3.5 SC B1 Publications Efforts to eliminate delay with publications as experienced in previous years were successful. Conveners have been reminded that the final reports of their respective


WGs should be "publication ready" when they are submitted to the Chairman and to SC Members, respectively, for final approval. Good progress was achieved by small editorial teams, which, based on comments of SC members, prepared the final versions of the respective documents for publication in ELECTRA or as Technical Brochures: Four publications were made in 2015:

WG B1.11: Upgrading and uprating of existing cable systems (executive summary in Electra 279 and Technical Brochure 606),

JWG B1/B3.33: Feasibility of a common, dry type interface for GIS and Power cables of 52 kV and above (executive summary in Electra 279 and Technical Brochure 605),

WG B1.40: Offshore generation cable connections (executive summary in Electra 280 and Technical Brochure 610),

WG B1.42: Testing of Transition Joints Between HVDC Cables with Lapped and Extruded Insulation up to 500 kV (executive summary in Electra xxx and Technical Brochure 622).

WG B1.43: Recommendations for mechanical testing of submarine cables (executive summary in Electra xxx and Technical Brochure 623).

Eight publications were due to be presented in 2014 / 2015: 2015

WG B1.28: On site Partial Discharges Assessment of HV and EHV cable systems

WG B1.34: Mechanical forces in large cross section cable systems

WG B1.35: Guide for cable rating calculations

WG B1.37: Guide operation of fluid filled cable systems In connection with the central office, SC B1 will carefully follow the publication process. This is of the highest importance for the earliest dissemination of information.

3.6 Tutorials Each WG closing should also prepare a tutorial. This has worked very well, and SC B1 now keeps quite an extensive library of prepared tutorials, available for all SC members to use when- and wherever appropriate.

3.7 SC B1 Web site

SC B1 created a Web site www.cigre-b1.org hosted by the Central Office in August 2000 and the Secretary was nominated as Web Master. A new design of SC B1 web site had been on line since June 15, 2005 and was regularly updated. This web site has become a very important tool in recent years. It is more and more visited and regularly updated.

http://www.cigre-b1.org/


At mid 2012, the web-site has been upgraded to a new one. All the content of the current SCB1 web site was moved successfully to the new one: http://b1.cigre.org Some new tools prepared by the CAG have been uploaded at mid-2013.

http://b1.cigre.org/


APPENDIX I: Advisory Group, Working Group and Task Force Forms (Dec 2014)

Strategic Advisory Group : P.Argaut (FR) WG B1.28

On site Partial Discharges Assessment Mark Fenger (CA) / 2008-2011

WG B1.35 Guide for cable rating calculations Frank de Wild (NL) / 2010-2013

WG B1.38 After laying tests on AC and DC cable

systems with new techniques Mark Fenger / 2012-2015

Chairman : Pierre Argaut (FR) Secretary : Alain Gille (BE)

CIGRE SC B1

WG B1.37 Guide operation of fluid filled cable systems

Colin Peacock (AU) / 2010-2013Pierre Mirebeau (FR) / 2009-2013

WG B1.36 Life cycle assessment and environmental

impact of underground cable systems Aude Laurens (FR) / 2011-2014

Tutorial and Publication Advisory Group:

W. Boone (NL)

WG B1.37 Guide operation of fluid filled cable systems

Colin Peacock (AU) / 2010-2013

WG B1.38 After laying tests on AC and DC cable

systems with new techniques Mark Fenger / 2012-2015

WG B1.41 Long term performance of soil and backfill of

cable systems Walter Zenger (US) / 2012-2015

WG B1.47 Implementation of Long AC HV & EHV Cable

Systems Milan Uzelac (US) / 2013-2016

WG B1.43 Mechanical Testing of Submarine Cables

Marc Jeroense (SE) / 2011-2014

Customer Advisory Group : E. Bergin (IE)

WG B1.34 Mechanical forces in large cross section

cable systems Johannes Kaumanns (DE) / 2010-2013

WG B1.42 Testing of Transition Joints Between HVDC

Cables with Lapped and Extruded Insulation up to 500 kV

Gunnar Evenset (NO) / 2012-2014

WG B1.44 Guidelines for safe work on cable systems

under induced voltages or currents Caroline Bradley (UK) / 2012-2015

WG B1.45 Thermal monitoring of cable circuits and grid

operators’ use of dynamic rating systems Blandine Hennuy (BE) / 2013-2016

WG B1.46 Conductor connectors: mechanical and

electrical test Milan Uzelac (US) / 2013-2016

Prospective Advisory Group: M.Marelli (IT)

WG B1.48 Trenchless technologies

Eugene Bergin (IE) / 2013-2016

JWG B1/B3.49 Standard design of a common, dry type plug-in interface for GIS and power cables up to

145 kV Pierre Mirebeau (FR) / 2013-2016

WG B1.50 SVL and bonding systems (design, testing,

operation and monitoring) Tiebin Zhao (US) / 2014-2017

WG B1.52 Fault location on land and submarine links

(AC and DC) Robert Donaghy (IE) / 2014-2017

WG B1.51 Fire issues for cable installed in air

Paolo Maioli (IT) / 2014-2017

TF B1.54 Behavior of cable systems under large

disturbances (earthquake, storm, flood, fire, landslide, climate change)

Harry Orton (CA) / 2014-2015

JTF SC B1/ICC Interactions CIGRE SC B1 & IEEE/PES

Walter Zenger (US) / Permanent


Study Committee No: B1

WORKING BODY FORM

Group No : WG B1.28 Name of Convener : Nigel Hampton (US)

TITLE of the Working Group :

On-site Partial Discharge Assessment of HV and EHV cable systems

Background:

Cable Systems undergo various steps in testing, specifically tests after installation. To provide additional information after installation, on-site pd measurements may be undertaken. Such measurements under field conditions may be complicated to perform, and complex to analyse, but can provide valuable data on the quality of the cable installation. There is a significant interest from the owners of using these techniques both for verifying the sound installation, but also for the purpose of diagnostic testing during the life of the cable system. The work of this WG, that has the strong support of IEC TC 20, will fill the need of widely accepted guidelines.

Terms of Reference:

The work should be limited to HV and EHV extruded AC cables, but addressing both commissioning and diagnostic testing,

The WG shall:

- collect experience with PD testing, with respect to methods/equipment and results

- evaluate the added value of the PD testing at site for commissioning and diagnostic testing

- evaluate the applied technology, taking into account what previous CIGRE and ICC WG’s have done so far

- recommend the protocol, to validate the on-site measurement results (calibration, sensitivity assessment)

- recommend guidelines for PD test procedures at site (voltage level, measuring time, measuring conditions

- identify widely acceptable requirements for commissioning and diagnostic testing

Deliverables:

An Executive Summary article for Electra

A full report to be published as a Technical Brochure

A Tutorial

Created: 2008 The full report shall be made available for final review at the B1 annual meeting in 2011.

WG members from: AU, BE, BR, CA, HR, DK, FR, DE, IT, JP, KR, NL, PO, ES, SE, CH, UK, US.

Other stakeholding SC’s: D1

Approval by TC Chairman : Klaus Fröhlich Date : 03/11/2008


Study Committee B1

WORKING BODY FORM

WG N° B1.34 Name of Convenor : Johannes KAUMANNS (Germany)

E-mail address: [email protected]

Technical Issues : 9 Strategic Directions : 1 & 2

Title of the Group: Mechanical forces in large cross section cable systems

Scope, deliverables and proposed time schedule of the Group :

Background :

There are no special “bad” experiences with “large conductors”, but the trend is going to larger and larger cross sections. It was identified through SC B1 target groups that a technical guide could reduce risk of poor design and installation.

Scope : HV and EHV extruded land cables for AC or DC application

Terms of reference :

The WG should:

Identify the forces that interact with the cable system

Address the interaction with all types of joints, including transition joints The internal design of the cable or the accessories is out of the scope. The work will be limited to cables with extruded insulation, but should study all types of sheaths and the different installation arrangements such as rigid, flexible, transition from ducts to rigid installations, installation in tunnels, shafts, bridges……. The WG should address: - short circuit forces , - forces derived from temperature - relevant aspects of installation design (clamping, offsets….)

The WG will recommend when necessary relevant calculations, tests or testing configurations

Deliverables :

The WG will deliver : - a technical report to be published as a technical brochure and an executive summary in

Electra

- a tutorial presenting the results

WG members from: Canada, Denmark, France, Germany(Conv), Japan, Italy, The Netherlands,

Spain, Sweden, Switzerland, United Kingdom, United States

Time Schedule : start : September 2010 Final report : 2013

Comments from Chairmen of SCs concerned :

Approval by Technical Committee Chairman : Klaus FRÖHLICH

Date : 14 August 2011

mailto:[email protected]


Study Committee No : B1

WORKING BODY FORM

Group No : WG B1.35 Name of Convener : F.H. De Wild (NL)

TITLE of the Working Group : Guide for rating calculations of HV cables

Background:. Cable ratings are generally determined by using IEC standards such as IEC 60287 and IEC 60853, but these documents do not cover all situations. As examples, HVDC cables, deep burial, horizontal drilling, multiple circuits are presently not included in these standards though these situations are more and more faced. Then, it is clear that in accordance with IEC TC 20, CIGRE SC B1 should address missing calculations and send the results to IEC for further consideration.

Terms of Reference: - To collect experiences and information from different countries - To assess and interpret the results from the inquiries and to make conclusions and

recommendations on how to make a cable rating study - To set up a general framework to guide the user to calculate the current rating of a cable circuit in

any situation - To report potential difficulties and problems with the methods, as well as to report recent

developments in the methods

Scope: All AC and DC cables with emphasis on HV and EHV cables, when possible extended to MV as well The WG will also take into account : - the crossings between cables and other heat sources - the temporary ratings

Deliverables: The WG will deliver : - a technical report to be published as a technical brochure and an executive summary in

Electra - a tutorial presenting the results

Created: 2010, Duration 3 years

Convener e-mail: [email protected]

WG members from: Australia, Belgium, Brazil, Canada, Denmark, Finland, France, Germany, Italy, Japan, Korea, Netherlands, Norway, Poland, South Africa, Spain, Sweden, Switzerland, United Kingdom, United States

Other stakeholding SC’s: IEC TC 20 WG 19

Approval by TC Chairman : Klaus Fröhlich Date : 01/06/2011




WORKING BODY FORM

WG N° B1.36 Name of Convener : Aude Laurens (FRANCE)


Technical Issues: 7 Strategic Directions: 3 - Focus on the

environment and sustainability

The WG applies to distribution networks: Yes

Title of the Group: Life cycle assessment and environmental assessment of

underground HV cable systems


Background :

Different High Voltage Cable types as well as their associated civil works and installation techniques do not impact the environment in the same way. In order to minimize such impact, it is important to develop the necessary tools that would enable the engineers and the decision makers to compare the Global Environmental Impact (GEI) of different underground cable systems over their whole life cycle (including end of life and disposal). A few methods have been devised by electric utilities, particularly in Scandinavian countries and Japan, to assess the environmental impact of Underground High Voltage Systems over their life cycle.

Terms of reference : - To analyze methodology and existing tools and to ascertain their range of application for High Voltage Underground Cable Systems. - To develop methodologies as appropriate for Life Cycle Assessment of Underground High Voltage Cable Systems and possibly appropriate to MV Cable Systems. - To provide a picture of the interaction of an underground High Voltage cable systems with the environment. - To provide the engineers and the decision makers with information which identifies opportunities for reducing the global Environmental Impact of Underground High Voltage Systems. This working group will not cover environmental or biological effects of EMF associated with Underground HV and MV Cable systems.

Scope : High Voltage AC and DC underground Land Cable systems. Lapped and extruded dielectric insulation

Deliverables : - Electra article - Technical guide (containing technical data, discussion, and case studies) - Proposal for tool for assessment - Tutorial for presentation at CIGRE conferences and workshop - Draft of ToR for a future WG or JWG covering other technologies (GIL) or other voltage ranges(MV)

Time Schedule : start : March 2012 Final report : 2015

Comments from Chairmen of SCs concerned : C3 (appointment of an expert from C3), B2( possible overlap with JWG C3/B1/B2.13 to be limited), B3 (include GIL)

Approval by Technical Committee Chairman : Klaus Fröhlich Date : 10/06/2012



WORKING BODY FORM

WG N° B1.37 Name of Convenor : Colin PEACOCK (AU)


Technical Issues : 9 Strategic Directions : 2

Title of the Group: Guide for the operation of fluid filled cable systems


Background :

The paper cables are very reliable and should continue their service as long as possible. The present risk is to see the cable suppliers leaving the field, without anybody able to repair the existing cable circuits.

Scope : The scope will exclude pipe type cables. It will cover AC and DC land and submarine cables

which have in principle the same problems. The voltage range is from EHV to distribution levels.

Terms of reference :

To establish the appropriate terminology

To collect information and experience on the operation of fluid filled cable systems, using a questionnaire developed by the WG. The WG should consider refurbishment strategies for the continued operation of self contained fluid filled cable systems.

To collate, summarise and review the information

To produce a working group report as a brochure recommending guidelines on the best practices for the continued operation of self contained fluid filled cable systems. The WG will address the technical aspects on the continued operation of these cables such as: recommended maintenance, testing (routine and after repair), refurbishment and modifications for improved performance, operational availability and constraints, fault repairs, oil system capacity reviews, fluid monitoring and analysis, leak location techniques and a cable and accessories suppliers list.

If time permits the following could also be studied: extension of service life, extension strategies including use of transition joints, cable cooling systems

Deliverables :

The WG will deliver : - a technical report to be published as a technical brochure and an executive summary in

Electra

- a tutorial presenting the results

WG members from: Australia, Belgium, Brazil, Canada, France, Ireland, Italy, Japan, Netherlands,

Norway, United Kingdom

Time Schedule : start : September 2011 Final report : 2014


Approval by Technical Committee Chairman : Klaus FRÖHLICH

Date : 14 August 2011




WORKING BODY FORM DRAFT

WG N° B1.38 Name of Convenor : Mark FENGER (Canada)


Technical Issues # (2):9 Strategic Directions # (3):1

The WG applies to distribution networks (4): Yes

Title of the Group: After laying tests on AC and DC cable systems with new technologies


Background : Extruded (XLPE) insulation is rapidly becoming the insulation of choice in both new

and replacement transmission class cable circuits. While the cable and accessories are tested in the factory, the workmanship to install the accessories can only be tested after the installation has been completed and before the cable system is put into service. As DC testing, commonly used for FF cables, is not efficient for XLPE cables for AC transmission systems, attention has to be focussed on AC testing methods. The testing of DC cable systems will also be addressed to define which technology is the most appropriate. In the past, test equipment capable of testing long lengths of cables were not available so that a soak test at operating voltage for 24 hours was carried out by connecting the cable to the power system. In the last ten years different power sources have been developed that have the power rating to test long cable lengths. These include AC resonant power supplies, damped AC (DAC) and, more recently, very low frequency (VLF). In addition, there have been significant improvements in diagnostic tools such as off-line PD and dissipation factor measurement to assess the condition of a cable system. However, as there are presently only withstand test levels given in IEC 60840 and 62067 for AC resonant test voltages, there is a need to establish test voltage levels for other voltage sources and also establish suitable diagnostic tests.

Scope :

The WG will examine the present status, including limitations, of available voltage sources capable of testing HV and EHV, AC and DC, land and submarine transmission cable systems. The WG will also investigate the practical implications, risks and test burden related to the different test methods. The WG will examine the technical considerations involved to establish test parameters for AC and DC cable systems such as voltage levels, test durations (number of shots for damped AC) and frequency ranges for the different voltage sources and recommend what work needs to be done to establish these parameters if the technical background is not available. If the technical data are available, test parameters will be discussed and recommended for use. The merits of different diagnostic tests will also be addressed. The final report will be passed to IEC for further consideration regarding standardization. Great care will be taken to the work of D1.48 "Properties of insulating materials under VLF voltages"

Deliverables : The WG will prepare a TB that will include:

(a) Results of a survey of present test practices in different countries for both AC and DC, land and submarine transmission cable systems

(b) Results of a survey of test equipment presently available or under development (c) A review of technical considerations to establish acceptance test conditions for both AC and

DC transmission systems (d) Recommended test conditions based on technical considerations

The WG will also prepare a paper for Jicable 2015 and a Tutorial

Time Schedule : start : July 2012 Final report : 2015

Comments from Chairmen of SCs concerned : SC D1

Approval by Technical Committee Chairman :

Date :



WORKING BODY FORM

WG* N° B1.41 Name of Convenor : Walter Zenger (US)


Technical Issues # (2): 9 Strategic Directions # (3): 2

The WG applies to distribution networks: Yes, Transmission and Distribution

Title of the Group: Long term performance of soil and backfill of cable systems


Background :

Existing and up-rated cable systems are loaded increasingly higher. This can be driven particularly by real time rating systems and by re-conductored systems with new high stress dielectrics permitting larger conductor sizes within the same duct or pipe. In all cases the higher loads result in higher operating temperatures for the backfill even if the rated operating temperatures remain the same. The higher loads will increase the cable / duct to soil interface temperatures that will impact the external thermal environment of the backfill and native soil. Depending on the aged backfill and soil condition, this can severely limit the potential capability of the technological advances. Many of the existing circuits have been in service for 40 or more years when engineered backfills were in their infancy. Limited knowledge is available of past backfill design and how it will change over time. Recent work showed that properties have changed, such as degree of compaction and stratification of backfill components. Reason for the changed physical backfill conditions could be road vibration, ground water movement or settling. Of particular interest is how high load conditions, change in physical properties and environmental changes will impact aged backfill and soil conditions. As part of this work a review of an improved soil thermal stability test method shall be considered. The existing Cigre critical temperature gradient test is difficult to conduct. A current US test does not offer information on cable operating with a controlled dry region around the cable. Collaboration with IEEE / ICC would be possible to develop a better critical temperature gradient test.

Scope :

1. To review the literature (experience, history) on the subject 2. To establish the appropriate terminology and characterization parameters. 3. To review methods to measure the thermal, mechanical and chemical soil / backfill properties and stability. 4. To review methods to measure the aging and long-term stability of soil and backfill properties over system life 5. To review technical methods how to mitigate deterioration of soil and backfill conditions including moisture depletion by vegetation or other utilities 6. To evaluate the consequences, if no action is taken, such as loss of ampacity, including cost and overheating of the cable system. 7. To integrate the information in a practical users guide. 8. To apply to extruded, paper, and paper-laminate cable systems 9. To apply to HV AC and DC land cable systems including direct buried, direct buried ducts or pipe, duct bank / manhole systems, and Horizontal Directional Drill (HDD) installations


10. To apply to HV AC and DC submarine cable systems including ploughing, jetting, trenching and HDD installations 11. To apply to MV AC cable systems of high importance

Deliverables : Technical brochure with summary in Electra, Tutorial


Comments from Chairmen of SCs concerned : B3, B4, C1, C3, D1

Approval by Technical Committee Chairman : Mark Waldron

Date : 28/02/2013



WORKING BODY FORM

WG* N° B1.42 Name of Convenor : Gunnar Evenset (NORWAY)



The WG applies to distribution networks: No

Title of the Group: Testing of Transition Joints Between HVDC Cables with Lapped and Extruded Insulation up to 500 kV


Background :

Although the extruded HVDC cable technology is developing very fast, lapped HVDC cables will still be on the market for many years. There are projects that consider massimpregnated cables for the submarine part of the route and extruded cables for the land part of the route. There is a need to define test specifications for how to qualify transition joints between these two technologies.

Scope :

1. Review relevant test recommendations for testing of HVDC cables 2. Review relevant test recommendations for testing of transition joints for AC cables 3. Prepare a Technical Brochure on testing of transition joints between lapped and extruded HVDC cables 4. Prepare report for Electra 5. Prepare a tutorial

Deliverables : Technical brochure with summary in Electra and tutorial




Date : 28/02/2013



WORKING BODY FORM

WG* N° B1.43 Name of Convenor : Marc Jeroense (SWEDEN)




Title of the Group: Recommendations for mechanical testing of submarine cables


Background :

Update of mechanical tests for submarine cables is needed since submarine cable installations are growing for higher powers and new applications (wind farm connections, dynamic power cables and deeper sea installations etc).

The existing recommendation from 1997 (Electra 171) needs to be updated in the light of the experience gained during the last 15 years.

Scope :

1. Cover both impregnated paper cables and extruded cables (AC and DC) including a review of cable installation methods and cable protection for submarine cables

2. Examination of relevant IEC standards, CIGRE recommendations and standards from the offshore industry (e.g. umbilical testing)

3. Assess the risk for mechanical damage during installation and cable protection 4. Assess the risk for mechanical damage after installation (anchoring, drag-net fishing, pile

driving) 5. Calculation of tensile tests to be updated and a more detailed background to be described to

the selected factors (security factors and torsion as well as dynamic forces) 6. Propose test methods to cover:

a. Dynamic cable system installations b. Very deep sea installations (including extruded cables) c. Impact tests

7. Consider the heat cycling influence on the metallic sheath and evaluate possible test methods 8. Update/introduce mechanical tests for rigid joint 9. Consider tests with for free-spans, strumming 10. Consider tests for the cable interaction with e.g. J-tubes, bend restrictors etc.

The WG should not consider umbilicals in general but follow the development of umbilical power cables.

Deliverables : The Working Group should prepare a Technical Brochure, a summary in Electra and a tutorial.

Time Schedule : start : February 2012 Final report : 2015


Approval by Technical Committee Chairman : Klaus Fröhlich

Date :27/02/2012



WORKING BODY FORM

WG* N° B1.44 Name of Convenor : Caroline Bradley (UK)



The WG applies to distribution networks: Yes

Title of the Group: Guidelines for safe work on cable systems under induced voltages or currents


Background : During several phases of a cable system life (installation / maintenance / testing / upgrading / removal), it can be necessary to work under induced voltages or induced currents:

During the pulling or the laying of a cable in the vicinity of an energized system: underground cable or overhead line During the jointing operations in the installation process When checking or maintaining link boxes During the repair of the cable after fault When removing the cable for disposal at the end of its life.

As hazardous conditions could occur, it is important to provide Target Groups (utilities, manufacturers,…) with guidelines for safe work on cable systems. NB: After several years of active work, IEEE/PES/ICC is now close to publish such guide, limited to installations in ducts and manholes.

Scope :

All topics related to work under induced voltages or currents on land or submarine cables shall be addressed in a comprehensive guide which will include the appropriate terminology. The WG should address :

1. Extruded or lapped cable systems 2. HV but also MV and even LV AC when they are part of the connection scheme, 3. Permanent or fault conditions (Cable system stresses under grid fault) 4. Methods to calculate induced voltages and/or currents in various possible configurations (including EMF or Magnetic effect from cables installed in the vicinity) 5. Protecting equipments (gloves, earthing systems....) 6. Jointing, Terminating and work on Link Boxes.

Deliverables : Technical Brochure proposing safe working procedures with summary in Electra and a tutorial. A set of dedicated Tutorials. The result of the work will be sent to IEC TC 20 for possible further consideration.

Time Schedule : start : April 2013 Final report : 2015



Date : 03/04/2013



WORKING BODY FORM

WG* N° B1.45 Name of Convenor : Blandine HENNUY (Belgium)




Title of the Group: Thermal monitoring of cable circuits and grid operators’ use of

dynamic rating systems.


Background :

Nowadays, due to a more variable situation and increasing loads in the power grids, a dynamic rating system and other measurement values aid the asset manager in making optimal decisions in planning investments in the High Voltage grid. Based on measurement a grid operator can on the one hand decide if a hotspot in network should be taken away to increase the capacity or if the hotspot should be managed with the dynamic rating system and on the other hand will know the load and overload possibilities in real time and for the coming hours.

Scope

1) To review the literature (experience, history) on the subject 2) To establish the appropriate terminology and characterization parameters 3) To collect the present experience with thermal measurements on cable systems by

means of a questionnaire 4) To define the needs of the grid operator 5) To determine which data should be collected in order to assess the transmission

capacity of the link 6) To collect information about the technology 7) To examine the points of attention during installation 8) To describe the necessary maintenance operations and the time intervals between

those operations 9) The WG will take into account system complexity, effectiveness, ease of operation,

maintenance, history, experience of workers, practicality of retrofitting (if required) to existing circuits and cost.

10) The following assets will be managed: EHV, HV and MV cable systems, Underground and submarine cable systems and HVDC cable systems

11) The following points are considered as out of the scope: Integration with a temperature monitoring system of overhead lines, Systems that do not involve temperature measurements, Type, sample and routine tests of the systems and Thermal model of the cable system

Deliverables : Report to be published in Electra, Technical Brochure and tutorial

Time Schedule : start : 2014 Final report : 2016



Date : 24/04/2014



WORKING BODY FORM

WG* N° B1.46 Name of Convenor : Milan Uzelac (United States)




Title of the Group: Conductor Connectors: Mechanical and Electrical Tests


Background :

Current IEC 61238-1 standard applies to connectors for medium voltage cables. There is no IEC standard for connectors for HV cables. The procedures from IEC 61238-1 along with manufacturer and user specifications have been used to type test HV cable connectors. The thermal, mechanical and resistance stability tests specified in current standard are applicable to HV but some requirements are specific to high voltage applications. These include dimensional and functional requirements of connectors within HV cable accessories, typically larger cable sizes, versatility of the conductor constructions as well as different circuit load patterns, short circuit levels and mechanical stresses due to tensile and thrust loads. The IEC WG16 of the TC20 commenced work on revision of current IEC61238-1 standard. During this work, some members of WG16, expressed interest that the scope of this standard is extended to high voltage cable application. The TF in charge of the revision believes this work needs to be done by a dedicated group of high voltage experts. At the Study Committee B1 meeting held in Paris on August 28 and 29 2012 it was agreed that a task force be established to consider if further guidance was needed on the testing of connectors for HV cable accessories. It was also decided during the meeting that the topics should be expended to cover mechanical loads, (not only thermal), to include all connectors (mechanical and other types) and to include termination and joints connectors.

Scope :

1 To review

The range and types of connectors currently available.

Existing international standards and the extent to which they cover the testing of

connectors.

Any work been done by CIGRE, CIRED, JICABLE…

Extent of service experience so far for different connector types.

Customer needs.

2 To analyse

Operation on high loaded systems where conductors are approaching or temporarily

exceeding maximum conductor operating temperature.

Thermo-mechanical performance of connectors under cycling loads.

Performance of connectors in short circuit conditions, taking into account thermal

and dynamic forces and actual network ratings.

Performance of connectors installed in cable joints and terminations

3 To propose thermal and mechanical test regimes for connectors for HV and EHV cables


with special attention be given to connectors for large size cables.

Type, routine and sample tests including mechanical, cycling and resistance stability

tests.

Consider practicality of the short circuit test for large-size conductors and test loop

arrangement.

WG should be free to consider mechanical tests (e.g. tensile, thrust forces…) in

order to evaluate mechanical strength of connection and physical properties of

connector itself.

WG should be free to consider separate or integral test sequences combining

mechanical, cycling, short-circuit and resistance stability (assessment) acting on the

same samples.

Extent of connector type test experience so far (for different connector types).

Evaluate necessity of performing type tests on connectors that already successfully

passed qualification tests per IEC 60840.

WG should consider range of type test approval

4 The WG should consider the tests that reflect mutual impact between connectors, cable

conductors and accessories.

5 The conductor connectors for HV and EHV applications are to be considered. The WG

will make recommendation to include or not connectors for MV applications.

Deliverables : Report to be published in Electra or Technical Brochure with summary in Electra. Tutorial

Time Schedule : start : January 2014 Final report : 2017


Approval by Technical Committee Chairman : M. Waldron

Date : 24/04/2014



WORKING BODY FORM

WG B1.47 Name of Convenor : Ken Barber (Australia)


Technical Issues 9 Strategic Directions 1

The WG applies to distribution networks (4): No

Title of the Group: Implementation of Long AC HV & EHV Cable Systems


Background :

The power transmission network has been developed during the last decades based on the use of overhead lines. EHV underground cables systems have been available since a long time, but their development has been limited by large capacitance and dielectric losses as well as relatively low current rating compared to OHL. However with the use of new materials and processing technology the situation has changed significantly, so that the constraints on maximum length and power transfer have been largely overcome. The difficulties in installing new overhead lines are making it essential to consider the use of longer underground cables links, as demonstrated by the increasing number of long underground projects. There are still however technical challenges to consider whilst planning new cable installations. The most sensitive topics are those concerning reliability, impact on the transmission grid and installation. Excellent work has been done by Cigre Working Group C4.502, “Power System Technical Performance Issues Related to the Application of Long HVAC Cables”. We propose the following definition of long length of HVAC cables for this topic:-

“A long length of insulated cable is one where the load due to the capacitive current (at power frequencies cables behave as capacitors therefore they generate reactive power) needs to be taken into account in the system design. Typically this would be 40 km for voltages less than 220 kV and 20 km for 220 kV or greater”.

Given the different scope of work, this definition is slightly different to that of WG C4.502.

Scope : The aim of the new WG is to create a Technical Brochure which covers the practical issues relating to system design, installation and monitoring of long HVAC cables. A particular focus will be made on:

1. Current state development (SCFF cable vs. XLPE cable, Surge arrestors, Reactive compensation)

2. Challenges for implementation (Matching power rating by hybrid circuits, controlling EMF)

3. System design (Amount of reactive compensation, Losses, Sheath bonding for long length)

4. Installation (Construction, Horizontal directional Drilling, Right of Way) 5. Monitoring (Temperature monitoring, control of route condition)

6. Maintenance (Fault location, access to route information)


7. Practical experience (Table of significant projects)

Deliverables : Technical brochure with summary in Electra and Tutorial

Time Schedule : March 2014 : Final report August 2016



Date : 24/04/2014



WORKING BODY FORM

WG* N° B1.48 Name of Convenor : Eugene Bergin (IRELAND)




Title of the Group: Trenchless technologies for Underground Cables


Background :

In October 2001 Technical Brochure 194 was published, describing “Construction, laying and installation techniques for extruded and self-contained fluid filled cable systems”. The Technical Brochure included a brief description of innovative techniques including horizontal drilling, pipe jacking and micro-tunnelling. TB 194 describes the techniques, their limitations and the changes in cable design necessary to make use of each technique (for example, the changes needed in order to match the ampacity of a shallow, direct buried installation). Although much of the information on trenchless cable installation in TB 194 is still valid, it is relatively brief and few practical examples are given. There is increasing pressure to underground transmission circuits and it is becoming more common for a length of underground cable to be introduced into an overhead line circuit. There is also increasing pressure to reduce the cost of undergrounding and reduce the disruption (e.g. to traffic flow) caused when underground circuits are installed. A number of significant technical changes to underground cable circuits have been seen since TB 194 was written; for example, extruded cable has almost completely superseded fluid filled cable for new installations, delivery lengths for land cable have increased and there is a trend towards larger conductor sizes. There has been a large increase in the use of cable in sensitive habitats (e.g. shore landings for AC cable from offshore wind farms and DC cable interconnectors). In some cases the landing sites of submarine cables have been contaminated by prior use. Trenchless technologies do not disturb such sensitive areas and have been used in these applications. In addition to changes in cable technology and attitudes to undergrounding, there have been technical advances in the methods used for trenchless installation since TB 194 was written.

Scope :

1. To review the range of trenchless technologies currently available for cable installation ( HDD, pipe jacking and micro tunnels, …) 2. To review the technical constraints (thermal, mechanical, civil, geotechnical and environmental) relating to the trenchless installation of HV cable systems.


3. To provide examples of where trenchless techniques have been used in the installation of HV cable systems, highlighting the benefits and adverse experiences in each case. 4. The full cable tunnels should be excluded because they have their specific issues like fire, smoke, access, sharing with other services, etc. to be addessed and this topic has already been dealt in the TB 403 “Cable Systems in Multi-purpose or Shared Structures” by WG B1.08.

Deliverables : Technical Brochure with summary in Electra, tutorial




Date : 30/06/2014



WORKING BODY FORM

JWG* N° B1-B3.49 Name of Convenor : Pierre Mirebeau (France)SC B1


Technical Issues #: 10 Strategic Directions #: 1

The WG applies to distribution networks (4): No

Title of the Group: Standard design of a common, dry type plug-in interface for GIS

and power cables up to 145 kV


Background: Taking into account the market trend in some countries towards a commoditisation of the High Voltage cables lower or equal to 145kV, the working group B1-B3.33 had concluded that there is room in these voltage levels for a standard design in parallel with the present designs.

Scope :

The goal of the JWG is to recommend a functional design of an insulator with a common interface.

1. Current is ≤ 1000A, short circuit ≤ 40kA 1 sec. Cross sections are ≤ 1000mm² Cu or 1600mm² Al

2. Technology has to be defined (inner or outer cone), with a detailed evaluation of technical advantages/disadvantages of the two technologies.

3. The number of sizes has to be defined; the short circuit current can be altered for the smallest sizes. Dimensions of insulator components have to be defined (current connection, electric design and properties, mechanical design and properties). The type and dimension of the main current connection have to be defined

4. Consideration to be given to the consequence of a termination failure, the upgrading of the cable link for higher current loads and installation constraints, with a special focus on the basement dimensions.

5. The design has to meet the requirements of IEC 62271-209 and IEC 60840 and there is a need to define the initial and cross qualification processes

6. The stress cone design and material, the lubricant and the design of the compression device should be left to the discretion of the accessory manufacturer within the limits of the standardised insulator properties.

Cigre TB 303 and the work of WG B1.44 and WG B1.46 should be taken into account.

Deliverables : Report to be published in Electra or technical brochure with summary in Electra, tutorial


Comments from Chairmen of SCs concerned : B3 (+Nomination of experts)


Date : 30/06/2014


CIGRE Study Committee B1

PROPOSAL FOR THE CREATION OF A NEW WORKING GROUP (1)

WG* N° B1.50 Name of Convener : Tiebin ZHAO (United States)



The WG applies to distribution networks (4): Yes / No

Title of the Group: Sheath Voltage Limiters and Bonding Systems (Design, Testing,

Operation and Monitoring)


Background :

The basic information needed to design a bonding system is included in several documents such as Electra 128-1990, TB 283-2005, and TB 347-2008. Some of these documents need to be updated. In addition it is noted that cable bonding components and related national regulations have changed in recent years. The WG plans to address related issues with sheath voltage limiters (SVLs) and bonding systems.

Scope :

1. Basic information

Provide an overview of the functions of the bonding systems.

Review existing documents and other engineering information related to bonding systems.

Review service experience depending on bonding schematics, standing voltage and withstand levels.

2. Bonding system design

Consider different bonding designs: single point, multiple point (solid), cross-bonding, and point out different challenges regarding screen protection of cable systems, including joints, terminations and link boxes.

Provide basic knowledge (voltages, current rating, and energy absorption) for selection and implementation of bonding leads, link boxes and SVLs depending on cable system parameters and bonding designs.

Provide recommendations for screen insulation coordination.

Provide guidance on cable system models for overvoltage calculation using computer software. May work with liaison members nominated by SC C4 if such interests arise from C4 side on modeling aspects of this task.

3. Testing of bonding system

Provide guidance on testing of bonding system components.

Provide guidance on testing of bonding systems after installation. 4. Maintenance

Provide recommendations on maintenance of bonding systems including SVLs.

Provide testing criteria while considering interference with implemented monitoring systems.

Consider monitoring of bonding systems

Deliverables : Technical brochure (that will supersede the existing documents) with


summary in Electra, tutorial and recommendations to IEC




Date : 06/02/2015

(1) Joint Working Group (JWG) - (2) See attached table 1 – (3) See attached table 2 (4) Delete as appropriate




WG* N° B1.51 Name of Convenor : Paolo MAIOLI (Italy)


Technical Issues # (2): 9 Strategic Directions # (3): 2, 3


Title of the Group: Fire issues for insulated cables installed in air


Background :

A significant concern is the fire safety of insulated cables installed in air, since it is often not practical for fire protection services to give a rapid response in case of fire. This subject has been raised in the Technical Brochure 403 “Cables Systems in multipurpose or shared structures”. Whilst it is possible to bury some of the more hazardous cables in the floor of the tunnel, provide protection barriers or install fire protection systems such as water sprays or other devices, these systems are all expensive. It was therefore important to establish if more suitable cable designs could provide an adequate level of fire protection without the need for separate protection systems. Quite often tunnels are “ventilated” with certain airflow, having an incremental effect on some of the typical fire behavior of cables, including fire propagation, development of smoke and to a lesser extend development of corrosive fumes Standardizing work was done by IEC, but in terms of fire behavior these standards, at present, are mainly applicable to low voltage cables. More recent developments of new designs and requirements of power cable systems in terms of flame retardant properties are not yet considered; for this reason it is difficult to apply the above mentioned standards to transmission and distribution.

Scope :

1. To review:

All existing international and national standard, any work done by CIGRE, CIRED, IEC, IEEE.

Extent of service experience, customer needs; so far for different connector types.

Papers presented at Conferences (e.g. Jicable).

Customer needs. 2. To analyze:

Type of Installation: single purpose (tunnel, substations) or multi-purpose (bridges, shared tunnels and other shared civil works)

Ancillary components like fire monitoring, sprinkler protection, barriers, and other control measures could be the object of a list of general rules/suggestions and civil works (improvements, arrangements) as well.

In addition, the effect of certain mitigation measures on the performances of cable (i.e.: current rating) should be considered.

As a final contribution, the WG could provide for a ranking of cables types/design in relation to fire risk.

3. To propose:

Suitable cable designs


Additional methods

Development Tests, Type Tests including Fire Tests. 4. To consider the whole range of cables from MV to EHV, mainly with extruded insulation, excluding joints; 5. To prepare only general rules for joints installation.





Date : 06/02/2015





WG* N° B1.52 Name of Convenor : Robert DONAGHY (Ireland)




Title of the Group: Fault Location on Land and Submarine Links (AC & DC)


Background :

The increasing number of land and submarine cable assets globally has created a focus on cable fault location capabilities. All faults in cable systems are different and cable fault location depends to a great extent on applying the appropriate technique or combination of techniques. The methods for locating power cable faults require competent engineers and service providers. Guidance is therefore required for engineers on the correct application of the various techniques available.

Scope :

1. To cover fault location on the following installed cable types: MV/HV/EHV; AC/DC; land and submarine cable systems; single core, 3-core and pipe type cables. 2. To focus on main insulation & sheath faults 3. To provide overview of existing fault location techniques and underlying principles 4. For land and submarine cable systems, to provide guidance and strategies for effective fault location for a variety of installation types including but not limited to:

Direct buried cable systems

Ducted land cable systems

Cables between GIS bays

Cables installed in horizontal directional drills and tunnels

Cables at large burial depths

Cable systems with different bonding types

Very long cables

… 5. To examine the different methods of pre-location and pinpointing from an accuracy and suitability viewpoint 6. To prepare a flowchart to assist in selecting appropriate methods according to fault type and cable type 7. To examine design factors (cable design and installation method) affecting fault location capability 8. To examine safety considerations 9. To examine marine vessel and support requirements for finding submarine cable faults 10. To collect case studies of fault location experiences 11. To examine training requirements for fault location personnel 12. To examine assess applicability of on-line methods to support fault location 13. To review new and innovative fault location techniques & future developments 14. The WG should not cover:

Leak location in fluid filled cables


Gas leak location on gas compression cables

Diagnostic testing

Defects in cathodic protection systems





Date : 06/02/2015



Table 1: Technical Issues of the TC project “Network of the Future” (cf. Electra 256 June 2011)

1 Active Distribution Networks resulting in bidirectional flows within distribution level and to the upstream network.

2 The application of advanced metering and resulting massive need for exchange of information.

3 The growth in the application of HVDC and power electronics at all voltage levels and its impact on power quality, system control, and system security, and standardisation.

4 The need for the development and massive installation of energy storage systems, and the impact this can have on the power system development and operation.

5 New concepts for system operation and control to take account of active customer interactions and different generation types.

6 New concepts for protection to respond to the developing grid and different characteristics of generation.

7 New concepts in planning to take into account increasing environmental constraints, and new technology solutions for active and reactive power flow control.

8 New tools for system technical performance assessment, because of new Customer, Generator and Network characteristics.

9 Increase of right of way capacity and use of overhead, underground and subsea infrastructure, and its consequence on the technical performance and reliability of the network.

10 An increasing need for keeping Stakeholders aware of the technical and commercial consequences and keeping them engaged during the development of the network of the future.

Table 2: Strategic directions of the TC (cf. Electra 249 April 2010)

1 The electrical power system of the future

2 Making the best use of the existing system

3 Focus on the environment and sustainability

4 Preparation of material readable for non technical audience

study committee b1 insulated cables 2014 -...

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