Trendsetting connections

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1 siemens.com/energy/power-transmission-solutions Trendsetting connections The world of power transmission solutions Answers for energy.

2 Power transmission solutions It takes new approaches and new technologies to meet the world s soaring demand for energy and to transmit power to where it is needed most. We answer this challenge with trendsetting technical expertise, groundbreaking solutions, and the extra portion of experience gained from decades of market leadership in many fields of power transmission technology. 2

3 Compelling solutions for any task The Siemens range of power transmission solutions comprises trendsetting, proven, and reliable solutions for AC and DC power transmission. They help bridge even the longest distances in a safe and secure manner, and they make electricity the sustainable, available, and efficient energy carrier of choice. Grid access One-stop turnkey AC and DC grid connection solutions from initial studies and financing support all the way to commissioning. HV cables The most economical alternative for underground AC power transmission. FACTS: SVC PLUS A new approach in reactive power compensation for better dynamic stability and improved power quality in AC power systems. FACTS: SC HVDC PLUS An innovative, spacesaving HVDC solution based on multilevel VSC technology. Series compensation increases the transmission capacity of an AC system without compromising its stability. AIS substations Turnkey high-voltage substations with air-insulated switchgear based on a wide range of high-voltage devices for flexible solutions. 3

4 Grid access solutions High-voltage DC transmission systems (HVDC) HVDC Classic UHV DC HVDC PLUS Flexible AC transmission systems (FACTS) Parallel compensation: Mechanically switched capacitors (MSC, MSCDN) Static VAr compensators (SVC) SVC PLUS (advanced STATCOM) Synchronous condensers (SCO) Series compensation: Fixed series capacitors (FSC) Thyristor-protected series capacitors (TPSC) Thyristor-controlled series capacitors (TCSC) Gas-insulated transmission lines (GIL) High-voltage cable systems High-voltage substation solutions Air-insulated switchgear (AIS) Gas-insulated switchgear (GIS) After-sales services (operation and maintenance) FACTS: Synchronous condensers Synchronous condenser solutions provide short-circuit power to improve the electrical stability of transmission networks. HVDC Solutions for low-loss long-distance DC power transmission and for grid interconnection. FACTS: SVC Static VAr compensation increases voltage stability and enables the control of reactive power. GIS substations Turnkey high-voltage substations with gas-insulated switchgear based on a wide range of switchgear modules to meet customer demands. GIL The perfect, extremely flexible choice whenever overhead AC lines are not an option. 4

5 The world is witnessing a rapid and profound transformation of the entire energy landscape. Above-average growth in demand for electrical energy prevails, as electric power has become the backbone of growth, prosperity, and progress. There is no doubt that electricity is the energy carrier that will blaze the trail into a more efficient, more diverse, and more sustainable energy system. However, there are new challenges to be mastered: Energy market conditions have changed fundamentally. Environmental aspects are considered more important than ever before. Growing urban centers are characterized by immense power consumption. At Siemens, we have envisaged this transition process at a very early stage. We have consequently embarked on the development of innovative technologies that help master the new challenges. This is why we already have a tradition of creating thought-leading solutions that make possible the efficient transmission of power to wherever it is needed. Today, our trendsetting transmission solutions pave the way for huge energy highways that reliably transmit energy from where it is sustainably generated to the centers of consumption over distances of hundreds or even thousands of kilo meters. They enable existing AC grids to operate at much higher utilization rates, while, at the same time, meeting higher demands on reliability and power quality. They help integrate the various renewable energy sources that have gained increasing importance. They support the emergence of highly performant international grid infrastructures spanning entire economic areas and even continents. The portfolio overview on the following pages illustrates how our solutions unlock the power of technology to meet the challenges the transformation of the energy system entails. 5

6 The world s first ultra-high-voltage direct current (UHV DC) transmission system connects the Yunnan and Guangdong provinces in China. The system operates on a voltage level of 800 kv and is a new milestone in bulk power transmission. Characterized by its particularly low transmission losses, it transmits 5 GW of power generated by hydropower plants over a distance of 1,418 kilometers from Chuxiong substation in Yunnan to the energy-hungry Pearl River delta in Guangdong province one of the most densely urbanized regions in the world and one of the main hubs of China s economic growth. Commercial operation of the first 800-kV pole started in December 2009, and the complete bipole has been in operation since June The system uses two series-connected 12-valve pulse groups per pole; one is rated 400 kv, the other is rated 800 kv and feeds the DC line. 6

7 UHV DC A new dimension of efficiency in DC power transmission The benefits of Siemens UHV DC solutions Ability to efficiently transmit bulk power over very long distances: up to 8 GW at a voltage of ±800 kv percent reduction in transmission losses and CO2 emissions with UHV DC compared to UHV AC Significantly smaller footprint and lower overhead line costs in comparison with UHV AC transmission UHV DC thyristor module equipped with 6-inch thyristors Demand for electric power keeps rising, but many existing AC transmission systems have already reached their capacity limits. At the same time, the share of renewable energy in the energy mix is growing. However, wind, solar, and hydropower is mostly generated far away from load centers. That s why there will be a need for bulk power transmission corridors that can efficiently handle long- distance power transmission in the gigawatt range. That s why innovative transmission technologies are required for point-to-point longdistance bulk power transmission. Siemens UHV DC technology takes high-voltage direct current (HVDC) power transmission to the next level. It makes long-distance power trans mission at a voltage level of ±800 kv technically as well as economically feasible for the first time ever. A single UHV DC system provides power capacities of up to 8 GW. Siemens UHV DC offers a key to increased performance and robustness of the trans- mission grid, to keeping pace with the steadily growing energy demand, and to a highly efficient way of carbon emissions reduction. The UHV DC converter consists of a number of thyristor modules equipped with new Siemens 6-inch thyristors, which are connected in 12-pulse groups. A major benefit of this layout is the relatively small size of the converter transformers. Furthermore, it increases the redundancy of the system, as each of the four converters of plus and minus pole can be bypassed and the assigned DC line can operate at a reduced voltage level of 400 kv. Thanks to thorough R&D efforts, Siemens is able to produce the entire range of components required for 800-kV DC power transmission and supply complete UHV DC systems from a single source. 4" 5" 6" High-performance Siemens thyristors 7

8 Photo Hawkeye Photography The first order for Siemens innovative HVDC PLUS tech nology was the Trans Bay Cable project, a submarine HVDC transmission link between San Francisco s city center and a Pacific Gas & Electric substation near Pittsburg, California. The system transmits 400-MW active power and ±170-MVAr reactive power as a STATCOM to increase the stability of the surrounding AC system. INELFE, the world s first VSC HVDC with two parallel systems transmitting 1,000 MW each, is under construction between Baixas, west of Perpignan in France, and Santa Llogaia, south-west of Figueras in Spain. It is an important component of the trans-european electricity network. The converter stations use HVDC PLUS voltagesourced converters in a modular multilevel converter arrangement with a transmission voltage of 320-kV DC. 8

9 HVDC PLUS Innovative multilevel technology for DC power transmission The benefits of Siemens HVDC PLUS systems Little space requirements thanks to compact, modular multilevel design Supply of passive networks and black-start capability Grid access for onshore and offshore power generation from renewable energy sources Converter tower Siemens HVDC PLUS, which is based on multilevel voltagesourced converter technology, ushers in the next generation of high-voltage direct current transmission technology. It is one of the most innovative technological answers Siemens has developed to master the energy challenge: an advanced, modular, and universally applicable solution for the transmission of up to 1,000 MW and above. HVDC PLUS is the preferred solution wherever space is at a premium. It is ideally suited for the onshore grid connection of power-consuming remote offshore platforms as well as power-generating offshore wind farms. It helps ensure and even improve the availability of electricity in densely populated megacities, and it improves the performance of the transmission grid with regard to system security. At the core of the system are self-commutated, voltagesourced converters (VSCs) in modular multilevel-converter (MMC) configuration. This makes possible a nearly ideal sinusoidal waveform on the AC side and smooth DC voltage without intensive high frequency and harmonic filtering. Moreover, the MMC topology allows for low switching frequencies, resulting in lower system losses, and its modular design ensures flexible converter station layout. The VSC offers independent control of active and reactive power, which makes HVDC PLUS fully suitable for AC voltage control, which is particularly helpful in connections with weak network conditions. Reactive power can be generated or consumed independently from active power transmission, and the system can also provide unbalance control to compensate large single-phase loads. Two-level Three-level Multilevel vac vac vac t t t 9

10 Photo A lok Choy, On-Off-Media.net The Gwynt y Môr 576-MW offshore wind farm lies 13 kilometers off the North Wales coast. It generates power with 160 Siemens 3.6-MW wind turbines, producing around 1,950 GWh of electricity per year enough to power one-third of all Welsh homes and saving around 1.7 million tons of CO2 each year. The array of Siemens wind turbine generators are connected to the two new offshore substation platforms via 33-kV cables in the seabed. Once onboard the platforms, the wind-generated power is transformed to high voltage (132 kv) for efficient transmission back to a new onshore substation at St Asaph in North Wales. The onshore substation is also built by Siemens and includes two sets of reactive power compensation equipment each containing a 50-MVAr SVC PLUS unit. 10

11 Grid access solutions Proven solutions for challenging environments The benefits of Siemens grid access solutions Proven track record and experience in offshore grid access projects Customized solutions based on proven technology and experience Turnkey delivery minimizing technical and financial risks OSP East of Gwynt y Môr wind farm Large-scale renewable energy sources, such as offshore wind farms, are posing new challenges for transmission systems and electricity networks. The share of renewable energy in the energy mix is expected to dramatically increase in the next decades, as countries strive to meet renewable energy and CO2 reduction targets and to ensure the security of power supply. This increase in renewable generation is matched by the demand for proven grid access solutions that are capable of reliably transferring power from large-scale renewable energy projects to the transmission system. Siemens AC and DC-based grid access solutions are suitable for the transmission of up to 1,000 MW and beyond. The approach is to provide turnkey grid access solutions, ensuring seamless project coordination and reducing interface risk for the customers. Siemens comprehensive range of solutions comprises early feasibility and network studies to ensure grid code compliance as well as design, manufacturing, construction, and commissioning of onshore and offshore substations. Offshore wind grid access projects are often remote from the centers of demand or even the established transmission infrastructure and located in harsh offshore environments; large-scale renewable energy projects require complex electrical solutions. With the scale and transmission distance of these projects ever-increasing, Siemens is able to draw on its position as a technology leader in high-voltage AC and DC power transmission to provide highly reliable and customized solutions based on proven Siemens technologies. Siemens experience in these projects is unparalleled, and Siemens specialists in several countries deliver highvoltage AC and DC grid access solutions across Europe and beyond. Outstanding experience, a comprehensive range of products, services, and solutions as well as proven technology make Siemens the supplier of choice when it comes to highly reliable grid access solutions. Onshore substation at St Asaph, North Wales 11

12 The 500-MW Greater Gabbard offshore wind farm in the Thames Estuary off the British coast has been in operation since 2010 and comprises 140 wind turbines. The wind farm delivers enough power for more than 500,000 British households. Three 45-kilometer-long cables bring the power onshore at Sizewell, Suffolk, where three containerized Siemens SVC PLUS converters connect the wind farm to the national transmission network. Siemens SVC PLUS provides voltage control and increases grid stability in the most flexible and innovative way: The highly successful system comes either containerized or installed inside a building. Today, numerous SVC PLUS systems all over the world help handle voltage fluctuations, increase system stability, and support the integration of renewable power into the grid. 12

13 FACTS parallel compensation Improved grid stability and power quality The benefits of Siemens parallel compensation Prevention of voltage collapses and blackouts Higher dynamic stability of AC transmission systems Improved power quality SVC in Devers, USA Parallel compensation Mechanically switched capacitors and reactors (MSC, MSR), which can also be equipped with a detuning network (MSCDN) to avoid system resonances, provide the simplest version of parallel compensation offsetting the network voltage. The fast and variable means of voltage control and network stabilization is the well-proven static VAr compen sator (SVC). This individually designed installation continuously controls and changes the voltage by switching and controlling reactive power elements. Siemens uses state-of-the-art light-triggered thyristors as the key power electronic element. Any operating range and mode can be accomplished by selecting an optimal configuration. The SVC control allows multiple ways of system monitoring and system voltage stabilization, including power oscillation damping. The SVC s major task is the support of the network during contingencies resulting in increased overall system stability. The SVC PLUS solution, a STATCOM (static synchronous compensator) provides similar functionalities, but features these in a space-saving and even more flexible manner. It is based on voltage-sourced-converter (VSC) technology with continuous control using high-performance transistors (IGBTs). The multilevel topology of converter modules results in a nearly sinusoidal voltage waveform which reduces the need for filtering harmonics to a minimum. Hence, significantly less space is required. Small standard configurations (±25, ±35, and ±50 MVAr) are available as containerized solutions, which also allows for easy relocation. Larger operating ranges are also possible with either multiple containers or open-rack configurations installed in a building. The underlying technology is also actively used outside the utility sector in traction power supply or industrial applications, such as flicker compensation. SVC PLUS converter arrangement 13

14 A large-scale transmission project was started in Brazil in 2010 to provide power for the center of the Amazon area: a 500-kV double-circuit overhead trans mission line with a total length of about 1,500 kilometers is being constructed to connect the cities of Tucuruí and Manaus, including a 340-km, 230-kV connection from the city of Jurupari to Macapá. The system is expected to be ready for commercial operation in Siemens engineered and delivered three static VAr compensators (SVC) and 18 fixed series capacitors (FSC). The FSCs, installed in parallel and in the range of 200 MVAr to 800 MVAr each, will reduce the reactance of the transmission lines to improve transmission capacity, minimize losses, and reduce voltage drop over the long distance. This will support and improve the stability of the electric network in the Amazon area. 14

15 FACTS series compensation Higher efficiency and investment deferral for AC grids The benefits of Siemens series compensation Increased power transfer capability of the grids Better use of existing AC transmission lines Efficient, modular, and cost-effective solution FSC Lugo, USA Series compensation Series compensation devices electrically shorten the transmission line by reducing the line impedance. The transmission angle is also reduced. This results in an increase in power transfer capability and allows the more efficient use of existing infra structures. The most common application is the FSC, which consists of the actual capacitor bank. The capacitors are protected against overcurrents and overvoltages by three different devices: arresters (metal oxide varistors, MOVs), triggered spark gaps, and finally a bypass switch. As the whole installation is on high-voltage potential, everything except the bypass switch is mounted on a platform. The thyristor-protected series capacitor (TPSC) replaces the MOVs by a thyristor valve allowing a quicker reinsertion of the bank after faults. The thyristor-controlled series capacitor (TCSC) provides additional features compared to an FSC. A thyristor- controlled reactor in parallel to the capacitor bank allows influencing the impedance smoothly. Power oscillation damping and load flow control, which all increase the system s stability, are the major advantages of this application. FSC Castanhal, Brazil 15

16 Siemens installed three 60-MVAr synchronous condensers at the Georgia Black Sea HVDC station in June This synchronous condenser solution will support the transmission network between Georgia and Turkey with the required short-circuit power in order to operate the newly installed HVDC back-to-back station. In Denmark, Siemens has delivered a 250-MVAr synchronous condenser solution that will start operation in summer 2013, providing the transmission system with a short-circuit power of more than 800 MVA in addition to reactive power control. The installation of this standalone synchronous condenser solution will enable the trans mission system operator Energinet.dk to operate the trans mission network without the need for a large thermal power plant. This makes the installation an economically and environmentally advantageous investment enabling the infeed of large amounts of renewable energy into the transmission network. 16

17 FACTS synchronous condensers Bringing grids in line with new requirements The benefits of Siemens synchronous condensers Provision of short-circuit power and inertia Steady-stage and dynamic voltage control Reactive power control of dynamic loads Synchronous generator Synchronous condenser solutions are being reintroduced worldwide to support today s transmission system requirements. The addition of renewables-based power generation to the energy mix, phase-out of conventional power plants, new HVDC systems, and the extension of power supply systems to remote areas influence the stability of transmission networks. Hence, the installation of synchronous condenser solutions has become necessary to provide sufficient short-circuit power, reactive power, and inertia to the transmission systems. The Siemens synchronous condenser solution comprises a synchronous generator connected to the high-voltage transmission network via a step-up transformer. The synchronous generator is started up and braked with a frequency-controlled electric motor (pony motor) or a starting frequency converter. When the generator has reached operating synchronous speed depending on the system frequency, it is automatically synchronized with the transmission network, and the machine is operated as a motor providing reactive and short-circuit power to the transmission network. The generator is equipped with either a brushless exciter or with a conventional static exciter with brushes. The two solutions have different characteristics with respect to dynamic behaviors, and are selected according to the project requirements. Contrary to power-electronics-based static VAr compensators (SVCs), a synchronous condenser features the major advantages of injecting large amounts of short-circuit power and providing inertia due to its rotating mass. Siemens offers tailor-made turnkey synchronous condenser solutions to address the customers needs based on proven, reliable in-house equipment, extensive know-how on transmission system requirements, and project execution experience. Siemens supplies a broad range of generators up to 1,300 MVA on full speed. The generators are based on air, hydrogen, and water-cooled techniques depending on customer requirements. Synchronous condenser building of the HVDC Black Sea Transmission Network, Georgia 17

18 In the past, high-voltage substations used to be industriallooking eyesores that were usually banished from urban centers. Today, Siemens state-of-the-art substation technology, engineering, and design makes it possible to integrate such substations into urban settings in a architecturally and stylistically compatible manner. West Bay Super 1 substation in Doha, Qatar, for instance, reflects the scale of the city s greenfield development projects, as well as the local utility s commitment to have these substations complement the surrounding cityscape. Despite the enormous power requirements of the substation, turnkey contractor Siemens was able to control the building and plot size by installing ultra-compact gas-insulated switchgear (GIS). Siemens finished the building with design embellishments that reflect the contemporary feel of West Bay and make a striking architectural statement. 18

19 High-voltage substations turnkey solutions The key to successful projects The benefits of Siemens turnkey substation solutions One-stop approach comprising all technical, financial, and ecological aspects of the station s entire life cycle Customized solutions based on proven Siemens technologies, even for the most challenging demands Freedom from coordination efforts and minimized financial and technical risk Siemens turnkey high-voltage substations prove their extraordinary reliability every day in virtually all regions of the world Siemens has all it takes to create and operate turnkey substation solutions that efficiently support the reliable supply of electrical power on all voltage levels: from decades of practical experience as an EPC contractor from a vast number of projects all over the world to unparalleled expertise in all transmission processes and all the way to proven excellence in project management. A distinguished tradition of innovation in power engineering, customized financing solutions, and outstanding quality standards in all production facilities worldwide round out the picture. Turnkey solutions for high-voltage substations provide the strong performance of one of the world s leading engineering companies and one-stop supplier of power transmission products, solutions, and services. The scope of services comprises consulting, project man agement, system planning, engineering, commissioning, and comprehensive after-sales support. Centers of com pe - tence and branches all over the world create local value and ensure that Siemens experts are within close reach of every project. After-sales services and recycling Financing support and consulting Feasibility studies Overall project management Engineering and design Training Site facilities and civil works On-site installation and commissioning Production Transport Factory testing Procurement 19

20 FGC, a Russian power plant operator, intended to improve, expand, and secure the electrical power supply for the future. They decided to replace a 40-year-old air-insulated switchgear (AIS) by a modern and space-saving gas-insulated switchgear (GIS). The challenge for Siemens was to deliver nine bay sections 500 kv, 32 bay sections 220 kv, and six bay sections 110 kv within ten months. The AIS had to be gradually replaced by the modern GIS in the inner city of Moscow without interrupting the power supply during installation. In 2007, Siemens constructed the GIS on minimal space on the area of the former AIS, setting an example for reliable and flexible technology implementation. 20

21 High-voltage GIS substations Reliable, flexible, and outstandingly compact The benefits of Siemens gas-insulated switchgear High reliability, availability, gastightness, and high degree of safety Economic efficiency, long service life, little maintenance requirements, and low life cycle costs Compact design, good accessibility and ergonomics, high degree of adaptability to individual requirements Siemens GIS have proven their reliability in numerous indoor and outdoor installations Siemens supplies high-voltage GIS for rated voltages from 72.5 kv up to 800 kv. The comprehensive product range holds ideal solutions for all indoor and outdoor switching applications up to the highest performance rates. More than 28,000 GIS bays for voltage levels of up to 750 kv are currently in operation in substations all over the world. Siemens particularly focuses on sophisticated switchgear solutions for installation in challenging locations. Highvoltage substations equipped with Siemens GIS can be integrated in urban settings in a way that makes them virtually invisible and entirely compatible with densely populated districts. These substations are sometimes completely underground, such as in Anaheim, California, or they are incorporated in other structures, such as multi-story buildings and car parks and even historical buildings. Siemens GIS are also an essential part of grid access solutions for renewables an aspect that is increasingly gaining importance. One of the main challenges today is to bring high-voltage levels right into the centers of urban areas. This requires switchgear that feature a small footprint, the utmost reliability, and very low noise and electromagnetic emissions. Siemens GIS are ideally suited to meet these requirements. Thanks to their compact design, Siemens GIS need very little space. They consist of a small number of modules that are combined into many field arrangements, meet all space and capacity requirements, and need very little maintenance. Moreover, Siemens GIS excel through low losses, outstanding gastightness, and very low electro- magnetic field emissions. They are virtually main tenancefree systems with low life cycle costs and high levels of reliability and safety, which is an issue of particular concern in urban settings, where large numbers of people are in close proximity to the substation buildings. Offering the highest-possible degree of mobility and flexibility with mobile high-voltage switchgear mounted on trailers or within containers, Siemens portable power solutions are a proven one-stop option whenever it comes to providing switchgear in next to no time and for temporary purposes, as is the case in disaster areas, for instance. With more than 40 years of GIS manufacturing experience, the largest installed base of gas-insulated switchgear, and a long track record of superior turnkey supply, Siemens is able to provide one-stop GIS solutions that also comprise all secondary technology, procurement, installation and commissioning on-site, and operational training. What s more, Siemens is also able to offer outstanding service and support in all matters of high-voltage substation technology. A tight-knit global network of regional business units, technical experts, and experienced engineers makes products and technical expertise available at short notice around the globe. 21

22 In 2007, Siemens commissioned India s first 765-kV sub station at Seoni in Madhya Pradesh for the Power Grid Corporation of India Ltd. (PGCIL). Seoni substation is the point at which the Sipat power plant feeds power into India s western and northern supply networks. The scope of delivery comprised 14 air-insulated switching bays for a voltage level of 800 kv, six 500-MVA transformers, civil works, and protection and control equipment. The commissioning of the plant and the associated raising of the transmission voltage from 400 to 765 kv were celebrated as India s entry into a new age in power supply. In the meantime, Siemens commissioned a number of further 765-kV substation projects, thus continuing to be a leading player in the Indian transmission sector and enabling PGCIL to boost the power transmission infrastructure of India. 22

23 High-voltage AIS substations Engineered for all environmental conditions The benefits of Siemens air-insulated switchgear Robust, time-tested components and systems based on over 80 years of practical experience Easy implementation of virtually any application and substation layout thanks to modular design Outstanding degree of availability, reliability, and operational safety More than 80 years of experience are the basis for today s Siemens substations equipped with AIS Siemens substations with air-insulated switchgear (AIS) are renowned for highest reliability, economical operation, and low maintenance requirements. An integrated provider of high-voltage systems for more than 80 years, Siemens produces all relevant switchgear components for AIS up to 800 kv as well as power transformers and secondary technology, such as protection, monitoring, and control systems and devices. Siemens AIS substations meet even the most demanding challenges, because the Siemens experts always consider the electrical parameters as well as the environmental conditions to which a substation is exposed. The modular design of all Siemens AIS switchgear makes possible the easy implementation of a wide range of standard applications. Moreover, particular solutions, such as step-up systems at power stations, the connection of power from renewable sources, and large transformer substations in extra-high-voltage transmission systems, can be set up, as the Siemens product range includes conductors for rated currents of up to 8,000 A and short-circuit currents of up to 80 ka. Moreover, Siemens also supplies particularly space-saving compact and portable air-insulated switchgear solutions. Siemens comprehensive range of services includes all studies required in advance of the construction or modern ization of a high-voltage substation, the selection of high-voltage devices, and planning and design for all required fields of engineering. This ensures the proper consideration of static loads for steel and civil works and the protection of switchgear facilities and workforce. Proper lightning protection as well as the observance of possible seismic loads are also taken into account. Moreover, around-the-clock service for entire substations is available. AIS for the grid connection of an onshore wind farm on the island of Fehmarn, Germany 23

24 In Germany, the expansion of Frankfurt Airport required existing 220-kV overhead transmission lines routed in close proximity to the new runway to be undergrounded for a distance of about one kilometer. The line operator Amprion con sidered two alternative solutions, conventional underground cables versus gas-insulated lines (GIL), and finally decided to install a GIL, which was directly buried, similar to a pipeline. One reason for the decision was the cutback of space consumption by 40 percent and the reduction of electromagnetic fields (EMF) by more than 90 percent compared to the power cable solution an appreciated benefit in the EMF-sensitive environment. The project is the first buried GIL in Germany and its two circuits provide a continuous transmission capacity of 1,800 MVA each. 24

25 GIL The next-generation transmission line The benefits of Siemens gas-insulated lines High economic efficiency thanks to very low losses, no need for phase angle compensation, and maintenance-free design High degree of safety and outstanding EMC properties Perfect complement to overhead lines thanks to high transmission capability GIL ensure minimal EMI at PALEXPO fairground in Geneva, Switzerland The space that is available for transmission systems is more restricted than ever before, and environmental requirements, such as EMC and fire protection, have gained in importance. Siemens second-generation GIL for high-power transmission are the best option when environmental or structural considerations rule out the use of overhead transmission lines. The outstanding features of a GIL system are its high transmission capacity, an EMC superior to any other transmission system, low losses, a high degree of safety, and flexible installation options. GIL can be laid aboveground, buried directly in the soil, or installed in tunnels. GIL consist of two concentric aluminum tubes. The inner conductor rests on cast resin insulators that center it within the outer enclosure a sturdy aluminum tube that provides a solid mechanical and electrotechnical containment for the system. To meet the latest environmental and technical aspects, GIL are filled with an insulating gas mixture of mainly nitrogen and only a small percentage of SF6. During service, the fully encapsulated design protects Siemens GIL against environmental influences. The use of high-quality materials make possible an absolutely maintenance-free product that requires only external inspection. Siemens has nearly forty years of experience of installing GIL in the most challenging surroundings. Thirty-five projects with an overall tube length of more than 90,000 meters are in operation all over the word, including installations within major cities such as Geneva as well as various vertical and inclined lines to cavern power plants in Europe, Asia, and Africa. GIL from Siemens invisibly transmit power into urban centers and bridge distances where overhead lines are unsuitable. GIL technical data Rated voltage Typical rated current (higher values on request) Rated short-circuit current Insulating gas Typical system length Impulse withstand voltage Capacitance 245 to 550 kv up to 4,500 A 63 ka/3 s N2 and SF6 mixture 100 m to 100 km 1,050 to 1,675 kv 55 nf/km Overload capacity up to 100% depending on design and requirements Typical outer diameter ~375 to 517 mm Weight per phase approx. 50 kg/m 25

26 Three 220-kV systems, kV connections, as well as 149-MV connections supply power to the steel plants in Salzgitter and Peine, Germany. Siemens was involved in determining the cable route, carried out implementation planning and construction site management, calculated the current carrying capacity and pulling force, and finally laid and installed the 220-kV and 110-kV cables during plant operation a total of 13 km of 220-kV cable, 46 km of 110-kV cable, and more than 100 km of MV cable. Siemens also accomplished the high-voltage connections on the converter platforms of the Borwin 2 and Helwin 1 wind farms from planning all the way to commissioning. The main task was the connection of two 600-MVA transformers and four shunt reactors to a 170-kV GIS on the low-voltage side and the connection of the transformers to a 362-kV GIS on the high-voltage side. More than one kilometer of different cables with diameters of 1,600 mm and 2,000 mm had to be arranged on minimum space. 26

27 High-voltage cable systems Customized solutions for the power systems lifelines The benefits of Siemens high-voltage cable systems Long-standing experience in complex cable-laying projects and in collaboration with international contractors, project management, and documentation Technically and economically optimized, non-proprietary solutions Short reaction times for fault clearance Installation on-site High-voltage cable systems are the lifelines of power transmission systems. Today, increasingly limited availability of space and other external factors restricting the transmission capacity of cable systems call for solutions of increasing tech nical sophistication: the need to ensure reliable power supply of megacities, the soaring energy demand in emerging regions, the increasing share of renewable energy in the energy mix. Siemens provides the full range of one-stop services for high-voltage cable systems up to 550 kv as well as vendor-neutral advice and support for entire systems and accessories. These services comprise all steps from engineering all the way to commissioning and final testing on a turnkey basis. 150 years of technical experience in cable laying from initial calculations all the way to cable termination and project commissioning, as well an excellent overview of the entire market, help select the right technologies and high-grade materials for any individual requirement in accordance with national and international regulations and guidelines. Assistance in system retrofits, conversions, and extensions, as well as in the dismantling and recycling of old installations rounds out the range of available services. HV cables technical data Rated voltage Types of cables 60 to 550 kv XLPE, oil-filled Typical rated current (higher values on request) Rated short-circuit current Insulation material Typical system length Impulse withstand voltage Outer diameter Weight per phase up to 2,500 A 208 ka/3 s XLPE 20 m to 100 km 325 to 1,675 kv 60 to 150 mm 3 to 40 kg/m 27

28 The Australian interconnector Basslink is an HVDC transmission system that links the power grids of the states of Tasmania and Victoria. Siemens supports the operator of the interconnector with a customized services package that includes necessary upgrades and spares supply over the life cycle of the system, as well as a 24/7 expert support line. In case of system outages or urgent customer queries, senior experts are available to react immediately and propose appropriate recovery measures. Remote access functionality 28 of the control and monitoring system makes possible immediate status analysis and enables Siemens to efficiently guide the customer s staff on-site in clearing the fault. Basslink has a world-record-breaking availability of over 98 per cent including scheduled outages. This underscores the quality of the system, the qualification of the operations team, and the quality of the support services that Siemens provides. The proximity and cooperation between user and supplier is essential for an asset which is supposed to operate efficiently, safe, and secure for more than 30 years.

29 After-sales services The secret of better availability and reliability The benefits of Siemens after-sales services Customized service packages Maximal facility availability Fast return on investment Siemens services ensure expert maintenance throughout the entire life cycle of transmission equipment Siemens is an established service provider for offshore and onshore AC substations as well as for HVDC systems. Driven by the understanding that creating value for the customers and managing risks is vital, the company provides a full range of valuable and reliable operation and maintenance services, such as comprehensive lifetime asset management services, remote diagnostics, and 24/7 expert hotline. These services, proven in various projects, such as Basslink, the interconnector between the Australian mainland and Tasmania, the Moyle Interconnector between Ireland and Scotland, and Neptune and Trans Bay Cable in the USA, help ensure first-class performance for a sustainable and secure power supply with DC long-distance transmission. Keeping up with high standards of health, safety, and environmental protection is the number one priority at Siemens. The company s effective business management systems are certified according to international standards. They provide a structured approach for the identification of hazards and risks. Adequate operational processes and procedures help identify, control, and eliminate such hazards. Siemens delivers comprehensive lifetime asset services for equipment and structures and provides proven systems for asset management and traceability. These services ensure the highest possible degree of availability and reliability throughout the entire life cycle of an asset. Trans Bay Cable HVDC PLUS system, USA 29

30 Published by and copyright 2013: Siemens AG Energy Sector Freyeslebenstrasse Erlangen, Germany Siemens AG Energy Sector Power Transmission Division Transmission Solutions Freyeslebenstrasse Erlangen, Germany For more information, please contact our Customer Support Center. Phone: Fax: (Charges depending on provider) support.energy@siemens.com Order No. E50001-G610-A131-X-4A00 Printed in Germany Dispo c4bs No fb 5064 WÜ WS 0213X.X Printed on elementary chlorine-free bleached paper. All rights reserved. Trademarks mentioned in this document are the property of Siemens AG, its affiliates, or their respective owners. Subject to change without prior notice. The information in this document contains general descriptions of the technical options available, which may not apply in all cases. The required technical options should therefore be specified in the contract.