The Polytransformer. The Multivoltage Substation Power Transformer

Transcription

1 The Polytransformer The Multivoltage Substation Power Transformer

2 The need for a single transformer for different transmission systems. Change of electric power industry to a fully competitive and deregulated market has highlighted the importance of asset management. Large power transformers represent a significant asset within the utility delivery system. These are the most important and costly components and the critical nodes in electricity networks. ABB has developed a new product in the transformer world, The Polytransformer. This transformer is designed with multiple voltage ratings, on the HV, the LV and tertiary side, that allow it to work in substations at different voltages. Impedances and MVA ratings are chosen to cover most of the applications. Single phase and three phases units are available Its compactness and flexibility of use make the Polytransformer the ideal universal transformer for any transmission system. Multifunctional tools The Swiss Army knife Light and compact: You carry it in your pocket. Many tools and different applications Useful and convenient: You never know when you may need it. Swiss knife multiple use Swiss knife ready for pocket. Polytransformer multiple voltage. Shell type transformer during transport. The Polytransformer Compact Ready for shipment and installation in any substation. Multiple voltage ratings Useful and convenient: You never know when you may need it.

3 The polytransformer: Universal multi-voltage transformer. Main features of the universal network-link transformer are: Multiple voltage ratings on the high voltage Multiple voltage ratings of tertiary winding. and low voltage side. The polytransformer The tertiary has internal taps to provide several is designed with internal taps providing different voltage levels to match different substation needs. voltage combinations to allow connection of different systems (i.e. from kv to 0 kv, kv to kv, kv to kv, 0 kv Maximum power rating limited only by to kv and 0 kv to kv, combined with transportation restrictions.,, and kv in the tertiary). Depending on the connection, power rating of the transformer Compact design. Shell form design helps varies. An on-load tap changer regulation is also to accomplish compact shipping dimensions provided. The different voltage rating alternatives providing in addition mechanical robustness can be selected by changing connections to withstand transportation and hauling loads. internally when the unit is being prepared This way, the polytransformer can be easily for shipment to a different station. shipped to many different substations The Polytransformer may be specified either for three phases or single phase execution. Minimum installation dimensions to optimize substation space requirements. Minimizing total dimensions allows replacement of a wide range of existing transformers or installation in substations with limited space. Short circuit impedance of the Polytransformer is designed taking into consideration the impedances of existing transformers. Parallel connectivity with other units is achieved by setting the appropriate tap in the on-load tap changer. Customized Design: Your Polytransformer will be designed to be electrically and dimensionally compatible with the different transformers in your transmission system. The design will meet your specifications and applicable standards. Standardized external components to reduce the number of spare parts and to facilitate their availability Compact design: 0 MVA, 00 kv Polytransformer ready for shipment. Polytransformer during test Low voltage multiple taps within design process. Low voltage multiple taps after manufacturing. Polytransformer, a multivoltage transformer approach, is a comprehensive product, which may be used as an universal network-link transformer. This means: compact dimensions to be shipped to any substation within the scope and different voltage ratings to connect alternative transmission systems. All in one single product.

4 Advantages and Applications of the Polytransformer. Do you need a Polytransformer in your network? Based upon the described features, several applications are possible for the Polytransformers: In ABB we can help you answer this question. Our proposal consists of three well differentiated steps: Spare Transformer: The Polytransformer may replace a number of different transformers (multi-voltage, impedance compatibility, parallel connectivity), located in different substations, in a limited time (high transportability), without major adjustments (standard adapted to your needs) New substations: When you need to expand your system, the Polytransformer will fit it. It will be designed to match the requirements of your network. It can be installed permanently on-site or used as temporary replacement of other units. Your new system will be commissioned and running on time. And you will know it is always available. Valuable asset: You can also cover most of other utilities or industries requirements. The Polytransformer can be rented, leased or lent to others in case of emergency or temporary need. 0 MVA, 00 kv Polytransformer in service with 00 kv / 0 kv connection. Peaks of Load: The polytransformer can also be used to provide additional power in the network during seasonal or emergency consumption peak periods. This reduces the risk of black outs, and will prevent other installed units from being overloaded Reduce your inventory and maintenance cost: As the Polytransformer can take the place of different transformers, your total fleet of transformers will be reduced, with the subsequent reduction of inventory, investments and maintenance costs. The first step is a technical and economical study of your fleet of transformers to be carried out in a collaborative way between your personnel and ABB. Our team of experts in ABB will outline this study considering the electrical characteristics of your network, shipping limitations of railways and roads, size limitations in your substations, your standards related to equipment and control (type, location, etc.), logistics, timing available for disassembling, transportation and installation, etc. From this study, several scenarios will be analyzed, to maximize network coverage and minimize investments. Second: ABB will design and manufacture the polytransformer that fits to your needs. And third, your local ABB Service will provide all necessary support for disassembling former equipment, transportation, assembling, installation and commissioning, including voltage adjustment, oil treatment, tap changer control adjustment, etc., every time you need to move your Polytransformer. Polytransformer during design process. The result will be a polytransformer that fits anywhere in your network and will be ready to replace other critical transformer in a record time

5 u u u u A shell form design for the Polytransformer. The optimal technical solution for the Polytransformer s special requirements is the Shell Form concept. There are several reasons supporting this selection: The flexibility of winding arrangement and The intrinsic flexibility of the shell form design the easy procedure to provide different tap to match existing impedances. Configuration connections inherent to a shell form transformer of shell form windings allows the designer to reach design, allows multi-voltage combinations for high, practically any level of short circuit impedance low and tertiary. without adding any complexity to the construction. In a close range of impedances, parallel The intrinsic mechanical robustness of shell form connectivity can be achieved by automatically withstands transportation and hauling loads. setting the appropriate tap in the on-load tap The Polytransformer is designed to be moved changer. and hauled to fit into different substations. A Real Case: 0 MVA, 00 kv three phase Polytransformer. A large utility had the need of some spare transformers to be used in case of emergency in some critical substations. Minimum objectives and requirements were: a three-phase spare unit with the maximum power rating which could be transported easily and quickly. This would permit keeping a spare transformer readily available for several substations. The utility provided ABB with the necessary information to reach an optimum design which would fit with the maximum number of installed units. A team of ABB experts reviewed this information and came back with a proposal that would meet these specifications, all in one single transformer. According to this proposal, four units have been ordered up to now with excellent results. At present some of these units are rented by the owner to other utilities. The compact dimensions of shell form. This aspect is critical in the case of the Polytransformer to comply with transportation restrictions. 00 kv 00 kv 00 kv W V U O W V U Shell Transformer winding arrangement., 0 0 The polytransformer was designed as a three phase, shell form autotransformer, multivoltage 00/0, 00/, 00/ kv, Max. power 0 MVA, with tertiary,,, kv, 0 Hz, Ynad connection, OFAF cooling and OLTC regulation at the neutral end (variable flux regulation) ( - ) ( - ) ( - ) ( + ) ( + ) ( + ) Connection diagram. A A A R - o + Test Room.

6 The Polytransformer was designed to be mechanically and electrically compatible with other three phases transformers installed in the 00kV transmission system (up to six different designs co-existing). Cooling equipment was designed with oil-air coolers to minimize the total space required for installation. All the accessories incorporated in this autotransformer are standard, compatible with accessories used in other transformers already installed in the network, thus helping maintenance operations and availability of spare parts. When the Polytransformer needs to work in parallel with other units having different regulating ranges, those have to be limited to work in the common part of the ranges. If the number of regulating positions is different, the transformer could be equipped with a programmable PLC. This PLC can be programmed to control the load tap changer and to select the optimum position in every case. It receives indication of the tap position of the transformer to parallel. With that information it selects the most suitable tap changer position at the controlled unit and an order is given to raise or lower the tap changer position accordingly. Overview from tertiary side (oil-air coolers in low voltage side). The polytransformer has been developed by ABB in the facility of Córdoba, Spain. Córdoba plant. Control cabinet with programmable PLC.

7 ABB Power Technology, S.A. ID/LAB 0000 Copyright 00 ABB Spain. All rights reserved. Designed by Global Drawing. Escritor Conde Zamora, s/n 00 Córdoba - Spain Tel.: + 0 / 0 Fax: + ABB Inc. Marketing 0 Semple Ave. St. Louis MO 0 -USA Tel.: + Fax: + We reserve the right to make technical changes or modify the contents of this document without prior notice. With regard to purchase orders, the agreed particulars shall prevail. ABB does not accept any responsibility whatsoever for potential errors or possible lack of information in this document. We reserve all rights in this document and in the subject matter and illustrations contained therein. Any reproduction - in whole or in parts - is forbidden without ABB s prior written consent. International patent pending.