superconductors, while also working on integrating the new 2nd generation superconductors based on Y(RE)Ba 2 Cu 3 O X Ca 2

Transcription

1 HTS Triax Energy Cable Systems HTS Cables and Accessories A New Way To Energ ize

2 Ultera helping to create the breakthrough for HTS technology The potential of HTS technology is immense. It is not just that energy suppliers no longer lose unnecessary energy during transmission across their extensive networks. Motors, generators and transformers with HTS conductors are also much smaller, and achieve the same output at much lower energy consumption. For business the use of HTS technology will mean long-term savings worth billions. For people it is the future purely and simply. In order to assist the HTS technology to achieve its commercial break-through and transform it as quickly as possible into effective long-term solutions, nkt cables and America s biggest cable manufacturer Southwire Company established the Ultera joint venture in Just like nkt cables, Southwire is also an innovator and pioneer in the field of superconductor technology. If the actual length of the cooperation between the two companies is taken into account, Ultera now has ten years of practical experience in the daily provision of HTS cables for energy supply in Europe and North America. Together they represent the three most successful installations worldwide with HTS cables, thus opening the door wide to a new way to energize. HTS Triax Energy Cable Systems High-temperature superconductor technology (HTS) is the key technology for tomorrow s electricity market. Compared with copper conductors, HTS ceramic cables have a number of significant advantages. For example they can conduct electric current without resistance at app. 200 C below zero. Transmission capacity is five times higher than that of conduc-tors made of copper, while current loss is reduced to one tenth. The development of HTS cables is in-separably linked to the name nkt cables. However, nkt cables is not just one of the world s leading companies in the design, manufacture and marketing of low, medium and high-voltage cables and accessories. In addition, with its workforce of 3000 employees this European high-tech corporation has been making history in energy technology for more than 130 years now. No wonder then that nkt cables has also led the market in researching and producing superconductive cables from the very beginning. As early as 2001 the first superconductive cable was put into operation in a public power supply network in Copenhagen. At the time a total of 50,000 households and companies benefited. In future it will be millions. HTS Cables with BSCCO tapes, copper stabiliser, Cryoflex dielectric, semiflexible cryostat Product Scope HTS cables can be configured in several ways using the same materials and production processes. The most efficient and high-performing configuration for the medium-voltage (MV) up to 72 kv is the HTS Triax design. nkt cables also has experience in coaxial single-phase cables which are suitable for higher voltages. The HTS cable conductors can also be supplied with a conventional warm PE insulation. nkt cables continually develops the voltage rating and the performance within the product scope described in the following table. nkt cables offers cable conductors made from the 1st generation Bi 2 Sr 2 Ca 2 Cu 3 O X superconductors, while also working on integrating the new 2nd generation superconductors based on Y(RE)Ba 2 Cu 3 O X materials into these cable designs. Property/Um/kV NT NE LV PE-insulated, single phase X X D D Coaxial, single phase X X D D D Triax, three phase X X X X D D Specialty conductors X (X) D D 2 NT: No Thermal Load, NE: No EMF, LV: Low Voltage specialty conductors, X: available, D: under development

3 Construction Code HT B C CR S WM 2Y Codes HT: HTS triaxial cable design CR: Cryoflex electrical insulation Construction code: HT-BC-CRS(WM)2Y B: BSCCO-type HTS conductor laminated with a metal sheath C: Added copper stabiliser for over-current protection S: Copper wire or tape screen (WM): Corrugated wellmantel semiflexible thermal insulation 2Y: polyethylene outer sheath Construction code with rigid thermal insulation: HT-BC-CRS(RL)2Y Construction code with YBCO-type HTS conductor: HT-YC-CRS(WM)2Y Type HT-BC-CRS(WM)2Y 7.6/13.2 kv Dimensions/Ampacity, 3x ka Cable core Conductor, BSCCO laminated, hollow ID mm Copper stabiliser, cross section mm Cryoflex insulation mm Screen, copper tape, cross section mm Outer cable core diameter mm Weight, HTS cable core, 3 phases kg/m Permissible pulling force kn Bending radius during laying/at terminations (min) m 3/1.5 3/1.5 3/1.5 3/1.5 3/1.5 Thermal insulation Semi-right corrugated duct, ID/OD mm 60/110 60/110 8/13 8/13 8/13 PE outer sheath thickness mm Total OD Termination OD mm Permissible pulling force kn Bending radius during laying/at terminations (min) m 3/1.5 3/1.5 3/1.5 3/1.5 3/1.5 Heat leak, duct section W/m Heat leak, joints W/ea Electrical data Conductor DC resistance at P nom µohm/m <10 <10 <10 <10 <10 Conductor AC loss at P nom *(T operation 67 K to 79 K) W/m/ph AC loss power factor, n P=k*l n Capacitance, eqv. phase-to-ground µf/km Inductance, eqv. single phase mh/km Power rating (continuous load) at 13,2 kv 1 circuit/2 circuits MVA 29/57 6/91 57/11 69/137 78/155 *Conductor AC loss at P nom depends on operation temperature, K 3

4 Type HC-BC-CRS(WM)2Y 21/36 kv Dimensions/Ampacity, 3x ka Cable core Conductor, BSCCO laminated, hollow ID mm Copper stabiliser, cross section mm Cryoflex insulation mm Screen, copper tape, cross section mm Outer cable core diameter mm Weight, HTS cable core, 3 phases kg/m Permissible pulling force kn Bending radius during laying/at terminations (min) m 3/1.5 3/1.5 3/1.5 3/1.5 3/1.5 Thermal insulation Semi-rigid corrugated duct, ID/OD mm 84/143 84/143 84/143 98/163 98/163 PE outer sheath thickness mm Total OD Termination OD mm Permissible pulling force kn Bending radius during laying/at terminations (min) m 3/1.5 3/1.5 3/1.5 4/2 4/2 Heat leak, duct section W/m Heat leak, joints W/ea Electrical data Conductor DC resistance at P nom µohm/m <10 <10 <10 <10 <10 Conductor AC loss at P nom *(T operation 67 K to 79 K) W/m/ph AC loss power factor, n P=k*l n Capacitance, eqv. phase-to-ground µf/km Inductance, eqv. single phase mh/km Power rating (continuous load) at 30 kv 1 circuit/2 circuits MVA 65/ / / / /354 *Conductor AC loss at P nom depends on operation temperature, K Type HT-BC-CRS(WM)2Y 42/72 kv HTS Triax Energy Cable Dimensions/Ampacity, 3x ka Cable Core Conductor, BSCCO laminated, hollow ID mm Copper stabiliser, cross section mm Cryoflex insulation mm 4,7 4,7 4,7 4,7 4,7 Screen, copper tape, cross section mm Outer cable core diameter mm Weight, HTS cable core, 3 phases kg/m Permissible pulling force kn Bending radius during laying/at termination (min) m 3/1,5 3/1,5 3/1,5 3/1,5 3/1,5 Thermal Insulation Semi-rigid corrugated duct, ID/OD mm 84/143 84/143 84/143 98/163 98/163 PE outer sheath thickness mm Total OD Termination OD mm Permissible pulling force kn Bending radius during laying/at termination (min) m 3/1,5 3/1,5 3/1,5 4/2 4/2 Heat leak, duct section W/m 1,5 1,5 1,5 1,7 1,7 Heat leak, joints W/ea Electrical Data Conductor DC resistance at P nom µohm/m <1 <1 <1 <1 <1 Conductor AC loss at P nom W/m/ph AC loss power factor, n P=k*l n Capacitance, eqv. phase-to-ground µf/km 1,6 1,7 2,0 2,2 2,2 Inductance, eqv. single phase mh/km 0,039 0,036 0,031 0,028 0,028 Power Rating (continuous load) at 50 kv 1 circuit/2 circuits MVA 108/ / / / /589

5 Accessories Contents Joints 5 Terminations 5 Cooling System 6 Monitoring System 7 High-current Switchgear 7 Product Scope nkt cables sells and installs the HTS Terminations and joints. We can also specify and source the cooling system as well as the monitoring system. Joints A 15 kv HTS Triax joint is 3 m long with an outer diameter of 31 cm. It contains the joints of all three phases and a common screen. 15 kv Triax Joint Terminations A 15 kv HTS Triax termination is 3.9 m long. The main body is installed at a height that gives the appropriate safety distance to the top bolts. The picture shows an outdoor version of the termination. nkt cables will convert this termionation to an indoor version on customer request. 15 kv Triax Terminations 5

6 Cooling System The following cooling solutions have been developed with Praxair Inc. The reliability of the cable cooling system is guaranteed through the following three features: Redundant cooling machines in a matrix of coolers Eight hours of backup in a cold storage tank Continuous 2/7 advanced surveillance by a cooler operations center The cooling power can be divided between one or several cooling stations. The emergency backup features are located in the terminal cooling stations. The line cooling stations are compact units of active coolers that can be placed at intermediate locations along the line. The distance between cooling stations depends on the available cross section for pumping the cooling fluid. Distances of 2-6 km are possible for compact systems. Closer spacing of the cooling stations improves the energy efficiency of the cable systems but requires supply- and servicepoints at several locations along the line. The matrix of coolers consists of N+1 or N+2 closed-cycle, low-maintenance cooling units. Cooling solutions can be developed together with major cryogenics system suppliers to fit individual user requirements. Terminal Cooling Station Line Cooling Station Line Cooling Station Terminal Cooling Station Terminal Cooling Station 6

7 Monitoring System The HTS Triax Energy Cable is monitored 2 h per day, 7 days a week by an advanced surveillance system. The surveillance system collects data on temperature, pressure and flow of the cooling medium, the temperatures of the terminations and joints load and the operastional status of the cooling machinery and back-up systems. These data are treated and analyzed automatically. The cable system operator is supplied with one of four simple status commands: 0 zero: The cable system is under service Do not energize 1 Green : The cable system is ready to operate 2 Yellow : Malfunction Manually disconnect w/o customer interruption 3 Red : Urgent malfunction Automatic disconnect with customer interruption The service provider can perform remote diagnostics through an advanced monitoring system with complete access to all system sensors. High-current Switchgear nkt cables can facilitate contacts to switchgear suppliers. The following are examples of commercially available switchgear products from various suppliers (2007). Examples A B C D E F G H Type Indoor Indoor Indoor Indoor Indoor Outdoor Outdoor Outdoor Model HVX VAH VAH VD HD PMI SPS2 PMI Ventilation passive passive active active passive passive passive passive Rated voltage kv * ** 15*** Rated current, max. A Short-circuit, max. ka 0/ /0 0/63 BIL kv making time ms breaking time ms *available in 12, 1.5, 36 and 0.5 kv models **available in 15, 25,38, 8and 78 kv models ***available in 121, 15 and 170 kv models 7

8 Installation and Protection Making it easy The HTS Triax Energy Cables are wellsuited for installation in high-density city areas where disturbances to traffic and infrastructure need to be kept to a minimum. nkt cables has developed an innovative new installation procedure, the HTS Two- Step Installation, where the cable core can be installed separately from the thermally insulating tube. This gives higher flexibility and quicker response to the requirements of each installation site, and above all, it reduces the number of cable joints. With nkt cables HTS Two-Step Installation approach, the cable joints can be spaced up to 2 km apart and there is only one joint per three-phase cable. Any open trenches can be re-closed even before the cable installation starts, and the access-holes need to stay open for only a minimum amount of time. HTS Two-Step Installation Prelude In the prelude to the installation procedure, the trench is excavated, PE ducts are installed, and concrete or other suitable protection is installed. The trench is then re-closed with rock, sand or soil. There are no special requirements on the thermal properties of the refill, since the HTS Triax Energy Cable does not release heat into the trench. In the case of a retrofit into an existing duct, the old cables are removed through access holes located at the old cable joints. The old cable is sent for recycling, while the duct is cleaned and lubricated. Step one In the first installation step, the thermally insulating tube (the Cryostat ) is provided in lengths of m. Shorter sections are joined together as they are pulled into the PE duct, for distances of m at a time (Fig.1). The cryostats are provided as flexible or rigid sections, depending on the curvature of the cable route. Spacings are left between successive cryostats. Step two The HTS Triax cable core is provided in lengths up to 2 km. It is inserted at one end of the trench, and pulled through several cryostat sections, with the help of cable pushers placed in the spacings between cryostat sections (Fig. 2). As soon as the cable is in place, the cryostat sections are joined together, and the access holes can be closed. Cable over-length is introduced through a patented procedure so that the thermal shrinkage can be accommodated. The work outside of the station areas is now complete and there are no further disturbances in the public space. Culmination The HTS Triax Energy Cable system is completed by terminating the cable in the station areas, and by connecting and starting the cooling system. Fig. 1 Fig. 2 8

9 Thermal Monitoring and Damage Detection A smaller parallel duct is installed near the cryostat. Optical fibres are pulled into the duct and used for distributed temperature sensing. Any damage to, or degradation in the cryostat will show up as a temperature signal at the location of the damage. Optionally, some of the fibres can be used for communication. Fibres for thermal monitoring can be provided as external skid wires in the case of a retrofit into an existing duct where no parallel duct is available. To sum it up: Making use of nkt cables expertise and engineering assistance already in the design stage, is the first step for smooth realization of the project. Engeneering assistance nkt cables can provide advanced engineering services already in the early planning stage of a project. Our engineers can provide electrical data, thermal simulations and proposed cable-system layouts as a part of early system studies to evaluate the best cable solutions. Making use of nkt cables expertise and engineering assistance already in the design stage is the first step for a smooth realization of your project. Service Contracts Service contracts are offered where the task of maintaining the cable installations in good condition is transferred to the shoulders of nkt cables. With this offer it is ensured that skilled personnel takes care of the superconducting cables. Regular checks of the conditions and, if necessary, initiation of remedial action at an early stage guarantee the value of the assets. 9

10 Testing Testing of cables and accessories comprises routine and special tests performed in the factory as well as tests on site after completion of the installation. These tests are performed in compliance with customer requirements and various national and international standards like IEC, EN, VDE, NF, BS, NEN, AEIC and others. Type tests and long-term tests have been made on components and also for qualification of complete cable systems. Newly develop ed cables and accessories are subjected to tests in the field lasting several years and comprising electrical and thermal stressing far beyond of what can be expected during normal operation. Research & Development & Innovation We know how nkt cables laboratory researches in and develops environmentally sustainable plastic materials for cables and leads and also handles quality control of raw materials and finished goods. The HV laboratories perform electrical tests on the cables. nkt cables technicians are internationally recognized for their specialized knowledge in compound development. nkt cables was the first company in the world to introduce leadfree PVC cables in which the poisonous lead stabilizers had been replaced by the relatively harmless calcium and zinc stabilizers. The idea was so good that the Danish Minister for Environment and Energy prohibited marketing cables with leaded PVC after December 1, Research plays an important role in all parts of nkt cables. Recently, NKT Research, nkt cables sister company, carried out revolutionary research in materials technology. This research enabled nkt cables to begin the production of fibre optical cables as early as in 1980 and to put the world s first superconducting HV cable in a public network in A complete recycling concept for all recyclable cable types By virtue of 0 years of experience within cable recycling, we are the only European cable manufacturer with a complete recycling concept for all recyclable cable types. We recycle cable waste at our environmentally approved recycling plant in Stenlille. Our plant in Stenlille is among the first 100 Danish companies with DS/EN ISO 1001 certification. We take our environmental responsibility seriously, for which reason environmental considerations play an important role in all departments of our company, irrespective of it being a question of product development, production or working processes or removal of worn-out products. For us it is not only a question of considering the environment when recycling and recovering cable waste. Environmental considerations are also decisive in our selection of materials and suppliers as well as in the planning of production processes. In this way we minimize the environmental impact related to the product life cycle: production - use - removal. Of course we also assist our customers to act in the best interest of the environment. Please contact us to learn how you can best dispose of your cable waste. Quality from beginning to end Quality from beginning to end is an essential part of nkt cables manufacturing philosophy. This is ensured by a combination of certified quality control throughout the production process and the use of raw material from approved sub-suppliers only. This places nkt cables in a fine position in international competition and secures flexibility to adapt rapidly to changing market requirements. nkt cables is of course certified according to ISO

11 Quality Assurance and Environmental Responsibility 11

12 nkt cables GmbH Schanzenstraße 6 20 D Cologne (Germany) Phone +49 (0) Fax +49 (0) infoservice@nktcables.com Direct contact for your region: Central Europe Carsten Wolff Phone +49 (0) carsten.wolff@nktcables.com Representation offices Belgium: +32 / Netherlands: +31 / France: +33 / Scandinavia and UK Brian Scott Phone +45 / brian.t.scott@nktcables.dk nkt cables Spain S. L. Edifici Testa Alcalde Barnils escal B, 3º piso, local 3 Sant Cugat del Valles E Barcelona, Spain Phone: +34 / Fax: +34 / info.es@nktcables.com Representation office GB: +44 / International Hans Damm Jensen Phone +49 (0) hans.damm.jensen@nktcables.com Representation offices Moscow: +7 (495) UAE: nkt K.F.C. siebel 12