GCCIA Phase 1. Making interconnection in the Gulf a reality GRID



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GCCIA Phase 1 Making interconnection in the Gulf a reality GRID 1

Making interconnection in the Gulf a reality GCCIA Phase 1 Gulf Cooperation Council International Authority The GCCIA is an organisation formed in July 2001 in order to create an integrated and sustainable energy economy amongst the six Gulf States. The aim is the interconnection of power grids between member states so that resources can be shared. The six countries include Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates. The GCCIA mission: to act in the interests of the people of the GCC Countries to provide reliable, competitive and sustainable transmission services. Objectives 1 - Interconnect the member states electrical power networks by providing the necessary investments for power sharing to anticipate power generation loss in emergency situations; 2 - Reduce the spinning reserves of each member state; 3 - Improve the economic power system efficiency throughout the member states; 4 - Provide cost-effective power sharing capabilities amongst the member states and strengthen collective electrical supply reliability; 5 - Deal with the existing companies and authorities in charge of the electricity sector in the member states and elsewhere in order to coordinate their operations and strengthen the efficiency of operation with due regard to the circumstances relating to each state; 6 - Apply modern technological developments in the field of electricity. Phase I: The GCC North Grid Challenge Saudi Arabia runs its electricity transmission network at 380 kv, 60 Hz. The other five countries use 400 kv, 50 Hz. Based on the asynchronous nature of the states to be interconnected, the best solution was to add an HVDC interconnection. The Phase I system components linking the networks of Kuwait, Saudi Arabia, Bahrain and Qatar include: l A double-circuit 400 kv, 50 Hz line from Al Zour (Kuwait) to Doha South (Qatar) via Ghunan (Saudi Arabia) with an intermediate connection at Al Fadhili (Saudi Arabia) and associated substations. The Interconnection Project The GCC interconnection grid has been planned in three phases: Phase I Phase II Phase III The GCC North Grid System interconnects Kuwait, Saudi Arabia, Bahrain and Qatar. l A back-to-back HVDC interconnection to the Saudi Arabia 380 kv, 60 Hz system at Al Fadhili. l A double-circuit 400 kv interconnection comprising overhead lines and submarine link from Ghunan to Al-Jasra (Bahrain) and associated substations. The GCC South Grid System will interconnect the independent UAE and Oman systems. (GCCIA is not involved in the Phase II execution). Interconnecting the North and South GCC Grids, completing the shared energy connection between the six Gulf States. The control centre located at Ghunan is linked with each member country s national control centre and will ensure security, control interconnection access, perform frequency and interchange regulation, coordinate interconnection operation, and transaction recording and billing. 2

Making interconnection in the Gulf a reality GCCIA Phase 1 Alstom Grid s core business is energy Alstom Grid, with over one hundred years of experience, is one of the world leaders in high voltage transmission systems and equipment. Our engineers were some of the pioneers in direct current technology and have been innovators in the field for over 40 years. Our expert design engineers create the most optimised solutions for each network based on present needs and in anticipation of future growth. All energy solutions are based on a project-by-project assessment, whether it s for long distance power transmission, energy trading between independent networks or connection between asynchronous grid structures. World leader in energy management systems Linking state, regional or inter-country power grids and making them work together intelligently is one of the things Alstom Grid does best. Our eterraplatform product is the top selling energy management system in the world. It has been integrated with the MiCOM suite of protection relays to compose a state-of-the-art network management, ensuring a flawless power supply. hvdc innovation Continuous improvement is at the forefront of all Alstom Grid research and development projects. Driven by our global HVDC Competency Centre in Stafford, UK, our engineering teams around the world bring unparalleled experience to each project. Our innovation programs are taking our customers into the realm of Ultra High Voltage Direct Current, the new energy highways of the future. Our mission: to provide reliable, efficient and environmentally-friendly transmission solutions to improve network stability and make electricity available to people everywhere. Alstom Grid s fields of expertise From evaluation to operation: l Network feasibility studies l Design and engineering l Turnkey project management l Energy Management Systems l Market Management Systems l HVDC and FACTS schemes l Telecommunications l Substation power electronics based on thyristor valves of up to 150 mm, 8.5 kv thyristors l Installation, commissioning and testing l Training and maintenance 3

Making interconnection in the Gulf a reality GCCIA Phase 1 Solving the Interconnection Challenge The Alstom Grid HVDC solution: Bringing state-of-the-art transmission to the Gulf Alstom Grid s H400 Thyristor valve is the heart of GCCIA s HVDC installation. These greater power density valves use series-connected, fully protected thyristors, each with an 8.5 kv rating and 125 mm diameter. The thyristors are controlled by Alstom Grid s industry-leading Series V digital control and protection system, offering fully-redundant operation, including monitoring and alarm capabilities. The challenges presented by the interconnection of the GCC networks were ideally suited to the application of an HVDC scheme. Direct current (DC) connection and transmission is used when alternating current (AC) transmission is not economical due to the distance, or impossible due to asynchronous frequencies. Because Saudi Arabia s network operates at 60 Hz and its Gulf neighbors are at 50 Hz, asynchronous AC interconnection was impossible. The only solution was to introduce HVDC into the grid. The Alstom Grid solution involved the creation of a 1,800 MW HVDC back-to-back link configured as three separate 600 MW substations. All three substations were built at the same location and constructed simultaneously. Each substation can operate autonomously or in a coordinated manner. This 3-pole HVDC converter interconnection substation is located next to Saudi Electric Company s existing Al Fadhili 380 kv AC substation. One of the main functions of HVDC is to constantly look for the occurrence of a power generation loss in the interconnected networks. When a loss of generation is detected, the HVDC link injects power into the system and, through the use of frequency control, restores the system to normal conditions. CUSTOMER BENEFITS l By linking the asynchronous networks in the Gulf region, generation requirements are reduced in each system thanks to the ability to share spinning reserves. l The exchange of energy between member states will reduce costs for each country. l HVDC offers greater control; transmitted power can be dialed up and even modulated in response to inter-area power oscillations. l Increased system reliability, especially under emergency conditions. l HVDC functions as a fault firewall. Faults can not propagate in an HVDC network or in an AC network with HVDC interconnections. 4

Making interconnection in the Gulf a reality GCCIA Phase 1 The Alstom Grid Automation solution: End-to-end innovation Alstom Grid supplied the integrated energy management, control and protection system for the entire GCCIA network. This system included the construction of the building which hosts the load dispatch and control centre and the interconnection to the national utilities in each country. The Energy Management System is based on Alstom Grid s industry leading eterrasuite of products and applications including eterratransmission and eterrageneration. Alstom Grid was responsible for the creation of the control and protection systems for the entire GCCIA substations network. All the available communications features were implemented and proven to work in a 400 kv transmission substation. Alstom Grid provided MiCOM IEDs and PACiS substation automation solutions. The Alstom Grid configuration software, PACiS SCE, was the first commercially available IEC 61850 configuration tool. A telecommunication system was deployed connecting the GCCIA control centre to the substations and utilities national control centres, designed to carry time-critical security services such as protection signals through DIP5000 equipment and IP-oriented data communications. Based on its many years of experience, Alstom Grid took the leadership role in the GCCIA project team to ensure the project s success. Today, GCCIA has the most cost-effective transmission protection and control design in the Gulf area. environmental challenges The Gulf environment, which is very hot, dry and dusty, presented a specific challenge for Alstom Grid. The converter substation is located in the desert, yet the valve hall requires high air quality for the HVDC thyristor valves. The valve hall airconditioning is a closed circuit. Top-up air is heavily filtered before use and valve hall air pressure is maintained slightly positive to prevent the ingress of contaminants during the frequent sand storms. The cooling equipment is the largest ever constructed for an HVDC installation due to the +55 C ambient temperature and the absence of fresh water for cooling. Parallel cooling for the thyristor valves is necessary to maintain temperature limits. 5

Making interconnection in the Gulf a reality GCCIA Phase 1 Alstom Grid end-to-end Automation solution: Efficient, stable, fully redundant To effectively manage an interconnected network, a specific Energy Management System (EMS) is required, located in the Interconnection Control Centre (ICC), coordinating the seven dedicated GCCIA electrical substations and each GCCIA member country s control system. IraK Phase I Phase II Phase III A fully redundant and dedicated telecommunication system interconnects all the sites. KUWAIT Each substation is managed through digital control systems to which are associated the relevant protections: AI Zour l Monitor and control of energy flows, l Dynamic Reserve Power Sharing (spinning reserves), l Trading support, l Energy accounting data for accurate billing between member countries. Iran AI Fadhili Substation AI Fadhili HVDC Substation Ghunan S/S Ghunan Control Centre Bahrain KINGDOM OF SAUDI ARABIA Jasra Qatar Doha Salwa Alstom Grid s digital control and protection solution The substation automation solution chosen by GCCIA is based on the mature IEC 61850 ethernet PACiS & MiCOM IEDs. The requested high availability is ensured by a full redundancy at all substation levels including the gateways to the GCCIA SCADA centre and emergency centre and the local control HMI PACiS OI. All MiCOM bay computer C264 and Px40 protections (including the P740 distributed busbar protection) are directly connected on the IEC 61850 ethernet network and work independently of each other. Directly available in each substation, engineering workstation allows maintenance operators to adjust any parameters on-line and perform all postmortem analysis. Alstom Grid s Automation experts designed and engineered the system; the cubicle design, assembly, installation and commissioning has been carried out by Alstom Grid s Dubai-based team. Competent and efficient project execution, combined with a close cooperation with all GCCIA involved contractors, has ensured on-time energization of the different North Grid System substations. The PACiS & MiCOM solution ensures: l Fully secured electrical network protection and control, l Redundant hot-standby communication to the SCADA, l Accurate and permanent monitoring of all primary substation elements, l Detailed disturbance recording and analysis. 6

Making interconnection in the Gulf a reality GCCIA Phase 1 Ghunan control centre - The brain of the GCCIA network Situated 60 km in the middle of the desert, the control centre manages not only the energy trading and distribution between all the new GCC interconnected networks, but it is also the central communications centre for all existing network management systems in the six member countries. Alstom Grid s telecommunications solution The telecommunication solution is based on a redundant transmission network: l A core optical network using Alstom Grid SDH STM-4 (622 Mbps upgradeable up to STM-16 2.5 Gbps) multiplexing equipment and optical amplifiers to cover long span links. The network is supervised through Alstom Grid NMS 5000 management platform and based on Alstom Grid MSE 5010 SDH equipment. l Back-up solution using digital power line carrier Alstom Grid Micom T390. All required operational information is conveyed through this network: l Teleprotection signaling between 400 kv GCCIA substations through Alstom Grid DIP 5000. l Data transmission using a robust, substation-grade data layer through the SDH optical system ensuring ethernet and IP services: - communications between ICC SCADA/EMS facilities and each of the interconnected National control centre EMS platform servers (Kuwait, Saudi Arabia, Bahrain and Qatar). - communication between the 400 kv substation DCS gateways and the ICC FEP servers. OMAN Al Wasset Al Ouhah Silaa United arab emirates OMAN Alstom Grid s Energy Management System Alstom Grid is the world leader in Energy Management Systems (EMS). The whole EMS suite of applications from our most recent eterraplatform product was deployed to coordinate the six member countries power systems. Network security is managed by eterratransmission and power management is managed by eterrageneration. The eterraplatform provides the following services to GCCIA: l Load forecasting, l Dynamic reserve monitoring, l Interchange monitoring, l Frequency regulation though a coordinated hierarchical AGC, l Control of the HVDC link between Saudi Arabia (60 Hz) and the other states operating at 50 Hz. 7

Alstom Gri HVDC converter transformers Twelve transformers were supplied in total for this project consisting of four HVDC converter transformers for each of the three poles. Each pole is comprised of the following ratings: an indepth look at the Al 1off 385.3 MVA, 380/97 kv, 60 Hz, Star/Star 1off 385.3 MVA, 380/97 kv, 60 Hz, Star/Delta 1off 380 MVA, 400/96 kv, 50 Hz, Star/Star 1off 380 MVA, 400/96 kv, 50 Hz, Star/Delta HVDC transformers have to satisfy all HVAC requirements including special considerations relating to both high currents and high voltages. HVDC schemes are less common than HVAC ones and hence the specific HVDC technology must be carefully maintained. The construction of HVDC converter transformers poses severe manufacturing challenges in terms of tight impedance control, AC and DC dielectric stresses and non-sinusoidal load current duty. Alstom Grid s global HVDC Power Transformer Excellence Centre in Stafford, UK, has all the necessary tools, resources, experience and expertise to manage projects of this type. HVDC control and protection Each converter pole has a duplicated Alstom Grid series V converter control and protection system to give the necessary power transfer control and provide protection to the converters and DC circuits. An overall duplicated series V master control with an integrated Human Machine Interface (HMI) allocates the required power to each of the poles and in addition interfaces to the GCCIA Interconnector Control Centre (ICC). Control can either be in economic power transfer to permit trading of power between regions or when necessary in Dynamic Reserve Power Sharing (DRPS) mode to allow very rapid support of a region suffering loss of power generation. Master control also controls the reactive power exchanged between the converter station and the AC systems by switching harmonic filters and by controlling the thyristor triggering angles. Conventional protection is provided for the converter transformers, harmonic filters, busbars and power cables. A transient fault recorder system is also provided. 380 kv 60 Hz Switchyard AI 8 Fadhili back-to-ba 3 x 60

d Systems: Switchyard Fadhili HVDC substation HVDC converters consume reactive power and also generate harmonic currents. The AC systems have only limited capacity to deliver or receive reactive power and limited tolerance to harmonic currents. Harmonic filters are provided with all HVDC schemes to approximately balance the reactive power consumed by the converters as they are capacitive at fundamental frequency and they reduce the harmonic distortion to acceptable limits. For the GCCIA project, these filters are switched automatically using Alstom Grid dead-tank circuit breakers, disconnectors and earth switches. As the converters generate high frequency conducted harmonics, PLC filters were added to block these harmonic currents from interfering with power line carrier communication in the AC networks. The switchyard is connected to the nearby GIS substations by underground 400 kv class XPLE cable. Valve hall At the heart of the converter substation are Alstom Grid H400 series valves using 8.5 kv, 125 mm thyristors. The very high ambient temperature (up to 55 C) on this project posed a significant challenge. Because the temperature of the valves active part (the silicon in the thyristors) needs to be limited to 90 C, the water-cooling plant required higher coolant flow rates than a standard HVDC link. The cooling pipe arrangement within the valve was changed to a parallel arrangement to increase the total flow rate into the converter. This required the largest water-cooling plant ever built for an HVDC installation. 400 kv 50 Hz Switchyard ck converter facility 0 MW HVDC converters need to be installed in a controlled environment with low levels of dust (converters have a tendency to act as an electrostatic precipitator and to accumulate dust on insulating surfaces). For this reason, the valves are installed in a purpose-built Valve Hall with controlled temperature, humidity and dust levels and with a slight over-pressure to minimize dust ingress. These factors were particularly important on this project which, because of its desert location, is prone to high levels of external dust. The valve hall contains not only the valves but all equipment exposed to DC voltages. The only equipment located outside is AC equipment which is much less vulnerable to dust accumulation. 9

Making interconnection in the Gulf a reality GCCIA Phase 1 Facts & Figures 3,800,000 hours of erection, testing and commissioning with no injuries. 9 00 Construction and installation crew members. 6 0 Testing and commissioning engineers and experts. 9,500 Tons / 26,000 m3 of equipment expedited from Alstom Grid or supplier production sites around the globe. 10 To attain high quality turnkey project delivery objectives within 36 months, Alstom Grid has created dedicated project teams: A utomation project management team was based in Al Khobar (Saudi Arabia) close to GCCIA and managed remote teams in Kuwait, Bahrain, Qatar and Dubai composed of Alstom Grid locally based technical experts and engineers. The team was supported by Automation Centres of Excellence in France (Massy, Energy Management Solutions and telecommunication solutions and Lattes, protection and control solutions) where dedicated teams of senior experts were also present on site to secure seamless project roll-out and the successive energization and go-live interconnection phases. 3 HVDC dedicated project management teams were created in France, in the UK and in Saudi Arabia under supervision of the project direction mainly based in Paris. Project direction was successively in the UK in the design stage and in Saudi Arabia in the site testing stage.

Bringing global technologies to the Middle East Charleroi, USA Air-insulated switchgear Massy, Lattes & St. Priest, France Automation equipment and software Fabregues, France Control shelters Macon, France Medium voltage switchgear Stafford & Lincoln, UK Power transformers, H400 Thyristor valve units Venice, Italy Disconnectors Dubai, United Arab Emirates, Automation protection Chennai, Noida India Automation protection equipment GCCIA Dubai 11

Alstom Grid Worldwide Contact Centre www.grid.alstom.com/contactcentre Tel: +44 (0) 1785 250 070 www.grid.alstom.com GRID Systems-L5-GCCIA-1839-V4-EN - Brochure Reference - Alstom, the Alstom logo and any alternative version thereof are trademarks and service marks of Alstom. The other names mentioned, registered or not, are the property of their respective companies. The technical and other data contained in this document are provided for information only. Neither Alstom, its officers nor employees accept responsibility for or should be taken as making any representation or warranty (whether express or implied) as to the accuracy or completeness of such data or the achievements of any projected performance criteria where these are indicated. No liability is accepted for any reliance placed upon the information contained in this brochure. Alstom reserves the right to revise or change these data at any time without further notice. Printed on paper made with pure ECF (Elemental Chlorine Free) ecological cellulose produced from trees grown in production forests under responsible management, and selected recycled three-layer fibres.