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CNC CIGRE SC COMMITTEE MEETINGSeptember 19, 2008

WinnipegSC – B1

Insulated Cables / Câbles IsolésRay Awad, Hydro Québec TransÉnergie

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• The field of activity of SC B1 concerns the development and operation of all types of AC and DC insulated cable systems for land and submarine power transmission (preferably HV and EHV cables and accessories).

• Within this field, the scope of work of the SC covers theory, design, applications, manufacture, installation, testing, operation, maintenance and diagnostic techniques of insulated cables.

SC – B1 Field of activity of the Study Committee

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• To facilitate and develop the exchange of engineering  knowledge and information between engineering personnel and technical specialist in the field of insulated cables;

• To add value to such knowledge and information exchanged by synthesising state-of-the-art and world practices;

• To make managers, decision-makers and regulators aware of the syntheses of SC B1's work in the field of insulated cables.

SC – B1 Mission of the Study Committee

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• To contribute effectively to the progress of insulated cable systems technology;

• To facilitate the integration of insulated cable systems in electric power networks and in the environment, covering the complete life cycle of cables;

• To maintain its leading position in the field of power cables by providing unbiased and neutral information on all essential cable aspects systems;

• To be recognised by the Electric Power Industry (EPI) as a leading and reliable partner with competence in all engineering issues related to insulated cable systems, i.e. technical, economical, ecological and social.

SC – B1 Goals of the Study Committee

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• The SC currently consists of  a Chairman, a Secretary, 24 Regular Members and 8 Observer Members.

 • The 24 countries represented by Regular Members are

Australia, Austria, Belgium, Brazil, Canada, Denmark, Finland, France, Germany, Ireland, Italy, Japan, Korea,  Norway, Poland, Portugal, Russia, South Africa, Spain, Sweden, Switzerland, The Netherlands, United Kingdom and United States whilst the 8 countries represented by Observer Members are China, Croatia, Egypt, India, Israel, Malaysia, Mexico, and Romania.

 • The 34 constituents of the SC come from Utilities (11),

Manufacturers (15) and Universities/Institutes (8).

SC – B1 Composition of the Study Committee 

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SAG will assist the chairman in the definition of the strategic direction of SC B1SAG will initiate the set up of new WGDuration: Permanent

Many Working Groups are expected to finish their work by the end of 2008 and presented their preliminary reports in Paris .

The term "Task Force" will not be used, only "Working Group".

SC – B1 Strategic Advisory Group (SAG)

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A common communication strategy of all SC CAG's should be establish through TC. CAG should consider if it is possible to improve the Paris session format.Duration: Permanent

SC – B1Customer Advisory Group (CAG) convener : E. Bergin (IR)

• Identification of Target Group

• Communication means with TGs

• Collection and mapping of TG’s needs

• Collection and evaluation of feed-back from TGs

• Deliverables:

report twice a year.

external actions approval SC Chairman and the SAG

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SC – B1 Tutorials Advisory Group (TAG) Convener : P. Argaut (FR)Duration: Permanent

Target Groups : Students and young engineers; Teachers / lecturers in education and training bodies; Engineers and managers in the electrical power sector (including civil works); Public;Examples of topics to be covered: Physics : ageing mechanisms, insulation materials; Components & Products: design, testing, cables, accessories; Power system impacts : technical and environmental impacts; System design:insulation coordination, thermal design; Construction and installation: innovative techniques; Maintenance; Asset Management; Environmental Impact Assessment.

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WG B1-06 (TB -303 issued in 2006)

convener : J. Becker (BE)Revision of Qualification Procedures for Underground HV Extruded Cable SystemsMain recommendations to IEC:• Prequalification Test (PQ) according to IEC 62067 mandatory for

manufacturers not yet qualified;• PQ tests mandatory if substantial changes of product, extrusion line or

higher stresses at accessories interfaces;• Requalification Test (RQ) in case of changes in accessories;• 180 heating cycle voltage test with min 24 hours per cycle (no need for

8760 hours);

• If failure during long term testing: possibility of repair and continue test (exclusion of faulted component);

• Impulse test after long term cycling voltage on whole cable loop preferred;• Prequalification test on HV cables if conductor stress higher than 8 kV/mm

or if insulation screen stress higher than 4 kV/mm (IEC 60840).

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WORK COMPLETED IN 2008 Collect statistics for the lengths of u/g and OHL; Analyse as function of voltage/power; Submarine and DC circuits excluded; Only include projects up to 2006; Describe significant underground cable projects (1996-

2006); Factors to be considered when comparing costs; Non-cost factors that must be taken into account.

WG B1-07

convener : S. Swingler (UK) Statistics on Underground Cable in Transmission Networks

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WORK COMPLETED 2008• SC B1 decided to launch a WG to investigate all aspects related to the co-

existence of cable transmission systems and other installations mainly in tunnels and bridges;

• The possibility of using existing structures like railway and motorway tunnels, subways, bridges, gas, water and sewage supplies etc. for the simultaneous installation of electrical power transmission systems is becoming more and more attractive with regard to construction cost, right of way etc. The questions behind this option are not only technical and economical but are also related to mutual impacts during construction, normal operation and hazards, environmental compatibility, safety risks and legal and administrative issues.

WG B1-08

convener : R. AWAD (CA)Cable systems in multipurpose or shared structures

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WORK COMPLETED 2007 Terms of reference:• To prepare proper definitions;• To list relevant cable and accessory types;• To review ageing mechanisms/defects /diagnostic methods for both paper

and extruded cable;• To prepare a questionnaire for utilities on present experience in end of life

strategies;• To develop a technical strategy for Remaining Life Estimation (RLE;)• To collect case histories;• To give guidelines for practical application of a general strategy for RLE.

WG B1-09

convener : W. Boone (NL) Remaining life of existing HV AC underground lines

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WORK COMPLETED 2008

Activities • Information and documents pertaining to previous studies on experience and

reliability have been obtained;• It has been decided that it will be necessary to prepare two questionnaires in order

to collect the data;• In order to facilitate and encourage replies, the questionnaire will be concise and

made as simple as possible. Questions will be focussed only on the information required to complete the task;

• Two task teams have been formed to develop draft questionnaires – one for Land cables and a separate task team for Submarine cables;

• Definition of terms used within the questionnaire are being developed;• The survey on land cable systems will cover the years 2000 to 2004 inclusive;• The submarine cable system survey will cover the period from 1991 to 2004.

WG B1-10 convener : B. Rosevear (UK) Update of service experience of HV underground and submarine cables

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WG B1-11 convener : F. Lesur (FR) Upgrading and up-rating of underground cable systems

WORK COMPLETED 2008Upgrading: Applying a solution that leads to improve the performance of a cable system. The performance refers to at least one of the function or property of the cable system:

transmitted power, service life, environmental impact, safety.Up-rating:Applying a solution that allows a cable system to be operated at a current level above its rated current:

reassessing the current rating (overload conditions, thermomechanical stresses, temperature monitoring, dynamic temperature rating, new calculation procedures, new design parameters);

decreasing losses (in metallic sheathes, in neighbour cables, in metallic structures or pipes);

increasing heat transfer (forced cooling, ventilated tunnels, special backfills, filling ducts, irrigating ground surface, hot spot mitigation).

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WG B1-21 convener : C. Jensen (DK) Third party damages on underground and submarine cables

WORK COMPLETED 2008

Defects caused by human activity• Consciously (dig-in, horizontal drilling);• Unconsciously (planting trees in the neighbourhood of cable links, changing

the profile of the land, installing new heat sources leading to possible overheating of installed HV cables);

• On short term basis (damage of insulation leading to breakdown);• On longer term basis (sheath damage leading to possible breakdown of the

insulation due to water treeing, overheating due to changed thermal environment leading to accelerated ageing and early breakdown).

Terms of reference• To propose improvements to current methods, after examination and

comparison of present methods/practices;• To propose guidelines on how to effectively control/reduce third party damages

of cables.

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WG B1-22 (2006-2009) convener : K. Leeburn (ZA) Cable accessories workmanship

Trends identified:• More

– Stress, Installers, Systems, Speed; – Larger conductors, Length;– Monitoring (Thermal, pd), Prefab;

• Less– Technical focus (Commodity), Skills (Supervisors, MV migration);

• Change– Foil Sheaths, Dry terminations, Water block;– Enamel wires.

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WG B1-23 (2006-2009) convener : H.Orton (CA)Impact of EMF on current rating and cable systems

• Terms of reference• Define the correct terminology

• Review practical EMF management methods

• Review practical design and construction considerations

• Review the cost effectiveness of different methods

• Quantify cable ampacity de-rating aspects of the various field management methods

The WG will neither cover any environmental or biological effects of EMF, nor discuss any specific levels of EMF

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WG 24 (2006-2008) Convener: Marco Marelli (IT)Test procedures for HV transition joints

WORK COMPLETED 2008

• Terms of reference:• Review the range of transition joints (TJ) currently

available• Review the existing international standards on TJ

testing• Align voltage levels to those specified in the IEC

standards for extruded cable systems• Propose test regimes for TJ and their associated cables.

Type, routine, sample and after laying tests should be considered.

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WG 25 Convener: Pierre Maribeau (FR)Advanced Design of La minated Metallic Coverings

WORK COMPLETED 2008

• Terms of reference:• Review and update the test as on cables with extruded

insulation and laminated protective coverings

• Issue a guide to use for non experts explaining what could be the different cable designs

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JWG B3/B1.09 Convener: Hermann Koch (DE)Applications of long high capacity Gas Insulated Lines in structures

WORK COMPLETED 2007

• Terms of reference • Collect information on existing GIL installations in

structures

• Identify the issues that need to be considered when installing GIL in specific or shared structures

• Give information how to handle large scale projects and to define what "long GIL" means

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New Working Groups• B1.28 On site Partial Discharge Assessment

• B1.29 Guidelines for maintaining the integrity of XLPE transmission accessories

• B1.30 Cable systems electrical characteristics

• B1.31 Testing of superconducting cable systems (TF)

• B1.32 Recommendations for testing DC extruded cable systems for power transmission at rated voltages up to 500 kV

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SC – B1 Past MeetingsB1 and Symposium on System development and asset management under restructuring, Osaka, Japan, October 29th to November 4th, 2007

The SC B1 meeting took place in Paris, August 2008

Paris 2008 session, the preferential subjects were:

No. 1: State of the art of AC/DC/HTS HV Cables

No. 2: Replacement of HV CablesNo. 3: Underground and Submarine HV Cables,

environmental and economic considerations

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Future meetings of B1 SC

• CIGRE Canada, Toronto, 2009

• Boznan, Poland September 22-24, 2009

• Paris, France, end of August 23-28, 2010

• Shnaghai, China 2011

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Preferential subjects for the 2010 session

1. Technical challenges overcome in newly installed underground and submarine cable systems

Current state-of-the-art in the designof AC and DC, submarine and underground traditional cable systems.

Current state-of-the-art in cable system instllation techniques

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Preferential subjects for the 2010 session

2. Key factors in current and foreseen development

of cable systems

Envirmental impact Balancing investement costs (including costs of

right of ways) vs life time costs (including costs for operation and maintenance, social costs, losses, dismanteling etc.)

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Preferential subjects for the 2010 session

3. State-of-the-art and trends for cable system testing

Qualification, type testing, routine testing, sample and after installation.

Representation of installation and operational stresses in testing

Diagnostic testing of cable systems