Power Transformers - Tamini

Established in 1916 forthe production ofelectrical transformers,TAMINI has become aleading manufacturer of acomplete range of type and sizeof power transformers andautotransformers - designed tomeet the specific requirementsof electrical power utilitiesand large industries - as well asof any type and size ofindustrial transformers forseveral different applications.1

POWER TRANSFORMERS AND AUTOTRANSFORMERSQUALITY ASSURANCE,The construction, the treatment and the assembly ofmanufactured at the workshop in Legnano, whichQUALITY CONTROL AND SAFETYthe winding coils which can be considered to be thehas 400 tonnes lifting capacity and testing facilitiesQA procedures are carried out and certified accordingheart of any transformer, are carried out in therated for up to 765 kV.to ISO 9001-2000 Standards.TAMINI workshops by teams of skilled workersSmaller transformers up to 25 MVA and 150 kV areQC is performed at every step: engineering,guided by experienced foremen.built in another workshop located in Valdagno, nearproduction cycles, procurement, testing and siteG.O. silicon-steel laminations or complete magneticVicenza.installation.cores are procured already cut or fully assembled fromLast, but not least, in the Melegnano workshop areAll the factories of the TAMINI Group have their ownspecialised manufactures of such components.manufactured special industrial transformers, intesting facilities suitable for the routine, type andThe clamping structures, the tanks and relatedparticular electric-arc furnace transformers andspecial test in accordance with IEC or IEEE (ANSI)components, fittings, cooling parts and tap changersrectifier transformers.75 MVA - 154.5/138 kV Regulating Transformer for Switzerlandand other worldwide recognized Standards (ASA,are subcontracted to specialized and qualifiedCSA, BSS, SEV etc.).Short circuit withstand test, if required, can bemanufacturers and submitted to the TAMINI QualityControl.CUSTOMER AND FIELD ASSISTANCEThe importance of a satisfactory after-sales250 MVA - 400kW Autotransformer under testingperformed at the internationally recognized Italianassistance has always represented for TAMINI theLaboratories of CESI. In the course of the yearsAny other operation, considered as fundamental forbasic belief of its performance all over the world.Tamini has submitted several HV and MV powerthe reliability and performance of the transformers, isSupervision, erection and commissioning operationstransformers to short circuit test as requested by thecarried out in accordance with in-houseas well as any service necessary during warrantyutilities or other end users including the 400 kV-250manufacturing, assembling and control procedures.period and afterwards, are directed and co-ordinatedMVA autotransformer shown at page 2.Therefore the completion of cores, the treatmentby the central office located at the GroupThe companies of the TAMINI Group definitelyoperations, the realization of auxiliary circuits, theHeadquarters and are carried out by qualifiedcomply with the most updated internationalfitting of components and instruments, as well astechnicians operating locally or coming from the220 MVA Substation Transformer for Luxemburglegislation for safety and environmental protectionaimed at reducing the noise level and using oil withinternal and acceptance testing and final checkingare performed by the factory staff, specifically trainedGroup’s factories.Any intervention is guaranteed immediately afternon-polluting ingredients (PCB was banned byfor every one of these operations.having identified the problem for the requiredTamini in the ‘ 70s) or non-flammable oil for specificunderground applications.The manufacture of large and medium powerassistance.In the main areas of North America and UK local100 MVA - 230 kV/26.4 kV Power Transformer for Canadatransformers is mainly concentrated in the twoassistance for any prompt intervention is assured byDESIGN AND MANUFACTURINGfactories of Novara and Legnano, having together athe TAMINI subsidiaries, located in the US and inFACILITIES FOR POWER TRANSFORMERStotal area of 36000 sq.mt. (see “TAMINI GROUPEngland. All the transformers leaving the TAMINIA staff of more than 40 engineers and qualifiedPROFILE” for a detailed description of thesefactories have their own comprehensive Instructiontechnicians develop the engineering design and thefactories).Manuals for Erection, Service and MaintenanceR & D. They are co-ordinated and controlled byThe factory in Novara specializes in the manufacturewhich are available in Italian, English, French,Senior Engineers with extensive experience in theof transformers up to 100 MVA - 220 kV. LargerGerman, Spanish, Russian, Dutch and other210 MVAr - 400 kV Shunt Reactor for Italydiversified fields of activity of the TAMINI Group.transformers with 400 kV HV and over arelanguages as required.Installation of a Power Transformer7

DESIGN AND FEATURES OF POWER TRANSFORMERSMAGNETIC CIRCUITSTERMINAL OUTLETSThe core is composed of silicon magnetic steelHV and LV outlets are carried out through bushingssheets, insulated by inorganic “carlite” with highfor connection to the external lines.chemical resistance to hot oil.The bushings are of different types, accordingPressboard insulation is interposed betweento the specified design: they can be eitherpackages of sheets. The joints columns-yokesof the oil/air type or oil/oil, in case of connectionsare usually of the interleaved step-lap type.to cables in oil filled terminal boxes,The core columns are strongly fastened utilisingor also oil/SF6 for connection to SF6 filledonly highly resistant clamping tape; no through boltsbus-bar ducts.are used. The yokes are clamped by a strong steelHV bushings are usually of the condenser type withPhase Shifting Transformer (PST) 160 MVA - 230000/155000 kV165 MVAr - 400 kV Shunt Reactorstructure tightened by rods.oil impregnated paper or epoxy resin insulation,250 MVA - 400/155 kV Power Transformerwhile MV or LV bushings are of the solid type.WINDINGS AND CONNECTIONSUsually the bushings are fitted with externalThe windings are made of electrolytic copper,porcelain insulators, however for the oil/air bushingsinsulated with pure cellulose paper.for outdoor installation, they can also be equippedStronger insulation is used on the terminal outlets.with silicon fins.Oil circulation through the windings is granted byFor LV and MV bushings the external connectionshorizontal and vertical channels, according to thecan be achieved through multi-contact elbowtype of winding. The winding type is designedbushings.according the voltage value.For installation in polluted areas the bushingsUsually HV windingsare designed with extended creepage distance320 MVA - 230 and 400 kV GSU Transformer for Turbogas Power Plant 320 MVA - 230 kV Power Transformerare of interleaved continuous disk type, whileLV windings are of transposed cable helical type.and special surface treatment.Winding Press EquipmentRegulating and tertiary windings, when installed,are also of helical type.The internal connections from the windingsto the bushing terminals and to the tap-changersare made by solid conductors or copper plaitsstrongly insulated and clamped to wooden supports.Special care is paid to winding stabilization,which is achieved through a process sequenceof drying, in hot air oven, and tightening by tie-rod,550 MVA – 400 kV Step Up Transformer under TestingOne of two 553/338/215 MVA - 403/19/15.75 kV Step-up Transformers for a 800 MWcombined-cycle power plantFinal Setting of Active Parts after Vapour-phase Treatmentboth on the single winding columns and on thewhole of each phase windings.9

DESIGN AND FEATURES OF POWER TRANSFORMERSCOOLING SYSTEMSseparate banks, with or without cooling fans.TANK AND OIL EXPANSION TANKOil and winding temperature indicatorsThe transformers can be designed for any applicableThe cooling can also be achieved with oil forced-airThe tank and the oil expansion tank, or conservator,HV, MV, LV bushings, as above describedcooling system following the requirements of theforced (OFAF) with oil to air coolers mountedare made of welded steel sheets andOver-pressure ventend users considering the site conditions whetheron the transformer side or in separate bank,reinforced structure, designed to support totalMarshalling box for signalling, controltheir installation is indoor or outdoor, in residentialand also with oil and water forced cooling (OFWF),vacuum. When the transformer is fitted withand protection circuitsor industrial areas and the size of the transformers.with vertical or horizontal oil to water coolersan on-load tap-changer, the conservator hasGrounding terminals or plateThe most used cooling systems for powermounted on the transformer side.two separate sections. The internal walls are paintedRating platetransformers are natural oil and air circulationwith a hot oil resistant coating while externallyLifting lugs for the complete transformer and for(ONAN) for the small-medium sizes, naturalTAP-CHANGERSthe tank is painted according to proceduresthe core & coil setoil-forced air (ONAN/ONAF) in one or two stages.The transformers can be equipped either withas per the internal QA prescription, dependingTranslation hooksThese systems are achieved by radiator banks,three-phase or single-phase motor driven on-loadon the site environmental conditions.Jacking padsmounted on the sides of the transformer tank, or intap-changers usually fitted on the HV side, and withThe anti-corrosion painting cycle of the tank,Bi-directional wheel and when required:conservator and external piping is always submittedLightning arresters, counters, supports and otherto the approval of the end users.surge protectionsOn specific request the conservator may featureCurrent Transformersan oil preservation system (salad bladder) or it canbe replaced by a nitrogen cushion.Other specific accessories upon client’s request.One of three Single-phase Step-down Transformers for a three-phase bank120/63/27MVA - 400/20/20 kV for Spain1600 kVA Special Transformer designed for Esplosive Enviroment 24/32/40 MVA Transformer for Lamar Utility Board, Colorado (USA)off-circuit tap-changers, usually hand operated,sometime motor driven.The on-load tap-changers are suitable for localand remote operation and are fitted with all theaccessories and with a marshalling cabinet mountedon the transformer side.They can feature a device for parallel operation.Vacuum-type on-load tap-changers are now usedmore and more.ACCESSORIESThe power transformers usually have the followingfittings and instruments subject to confirmation and inaccordance with the requirements of theend-users:Oil conservator as above described, completewith oil level gauges and air breathers for bothtransformer and on-load tap-changer sectionsBuchholz relay cooling systems as abovedescribedMotor-driven on-load tap-changer, completewith all necessary accessories and centralizedcontrol boxOff-circuit tap-changerCooling equipment, depending on cooling methodOil drain, filling, sampling and filtering valves50 MVA - 220/132 kV Mobile Transformer Typical Substation Transformer for German Market410 MVA - 400 kV Power Transformer116.4 (40) MVA, 230/63,23 ÷ 0/(10) kV Regulating Transformerfor Aluminium Smelter11

MILANOA1A51AUTOSTRADA DEL SOLESS415SP415S. DonatoMilaneseSS9LinatePAULLESES. GiulianoMilaneseSTRADA STATALE 415VIA CERCA VIA CERCASS415PaulloAll sales and administrativeactivities of the Tamini Groupare directed from the Group HeadquartersHeadquartersTAMINI Trasformatori s.r.l.Via Cesare Battisti 4320077 Melegnano MI - Italytel. +39.02.982051 fax +39.02.98230322www.tamini.itA50TANGENZIALE OVESTE35TANGENZIALE OVESTSS9VIA EMILIASP39Transformer Production FacilitiesTamini MelegnanoVia Emilia 3720077 Melegnano MIGps Coordinates:45° 21’ 40.70” N9° 19’ 46.40” EA1MELEGNANOTamini LegnanoVia P. Ovidio Nasone20025 Legnano MIVerbano TrasformatoriCorso Risorgimento 20928100 Novara NOV.T.D. TrasformatoriVia Gasdotto 636078 Valdagno MINorth American OperationsTamini Transformers USA2803 Butterfield Road, Suite 385, Oak Brook, IL 60523 USAtel. 630.368.9907fax 630.368.9910