Load cell for transformer and method for manufacturing a load cell for a transformer

Abstract

A load cell (1) for measuring forces in a transformer, comprises a measuring portion (4) and a sensor (5) for measuring a deformation of the measuring portion (4), and comprising a load cell housing (2), wherein the measuring portion (4) and the sensor (5) is embedded in the load cell housing (2), wherein the load cell housing (2) comp rises at least one supporting structure (13) for limiting a force exerted on the deformable portion (4).

Description

[0001]P2024,0794 WO N / P230232WO01 September30,2025 -1 - DescriptionLoad cell for transformer and method for manufactur ing a loadcellfora transformerThe present disclosure relates to a load cell for atransformer. The transformer may be a power transfo rmer. Theload cell may be configured for measuring forces in an activepart of the transformer. The forces may be forces i n awinding, a core, or in another region of the active part suchasa clamping system.In transformers, winding axial forces may occur whe n highcurrent flows through the transformer windings. Due to theinteraction of magnetic fields generated by the cur rent,mechanical forces occur in the windings. Large dyna micwinding axial forces may appear particularly during shortcircuiting events.In addition to that, the transformer windings are c ommonlysecured in place by a winding clamping system, exer ting astaticclamping force on the windings.The static and dynamic forces exerted on the windin gs are animportant factor in the integrity of the transforme r. Bymonitoring these forces, mechanical stresses in thetransformer can be determined. In addition to that, thewinding clamping system can be adjusted to the meas uredforces. Furthermore, the theoretical calculation of the axialwinding forces can be improved by a comparison with themeasured forces, allowing predictions on the status of thetransformer. P2024,0794 WO N / P230232WO01 September30,2025 -2 -US 2015 / 235759 A1 discloses a high-voltage transfor mercomprising a sensor system with a sensor head compr isingBragg gratings and an optical fiber. The sensor sys tem servesto determine a temperature of two successive windin gs and acontact pressing force of the windings acting on th e sensorfrom a shift of the wavelength spectra of the Bragg gratings.Embodiments of the disclosure relate to an improved load cellfora transformer.According to a first aspect, a load cell for measur ing forcesin a transformercomprisesa measuring portion and a sensorfor measuring a deformation of the measuring portio n. Thesensor is attached to the measuring portion. The lo ad cellcomprises a load cell housing, wherein the measurin g portionand the sensor is embedded in the load cell housing . The loadcell housing comprises at least one supporting stru cture forlimiting a force exerted on the deformable portion.The load cell may be configured for measuring force s in anactive part of a transformer. The forces may be for ces in orgenerated by the windings and / or the core, for exam ple. Theforces may be also forces in or generated by a clam pingsystem ofthe windingsand / orthe core.The forces maybe axialforces,in particularalong a direction ofa windingaxis of the windings. As examples, the load cell ma y beconfigured for measuring axial forces within a wind ing orfor measuring axial forces within a clamping system or formeasuring axial forces between a winding and a clam pingsystem ofthe transformeractive part.The transformer may be a power transformer. The loa d cell maybe configured to be positioned in or near an active part of P2024,0794 WO N / P230232WO01 September30,2025 -3 -the transformer. The active part of the transformer may bepositioned in a tank filled by an insulating liquid such asan insulating oil. The axial winding forces may occ ur in theform ofdynamicforcesin case ofshort-circuiting orasstatic forces due to a clamping of transformer wind ings.The measuring portion may be configured to expand w hen theload celliscompressed.The compressive force may be appliedin an axial direction. The expansion of the measuri ng portionmay be perpendicularto the axialdirection.Itis alsopossible that the force acts at a slight angle to t he axialdirection, e.g. when the load cell is mounted sligh tlymisaligned to an axial direction of a transformer w inding. Inthis case, the main component of the force may be a long theaxialdirection ofthe load celland the expansion ofthemeasuring portion may be perpendicular to the axialdirection.The measuring portion may comprise a ceramic materi al. Othersuitable insulating materials may be used. The mate rials mayhave a low thermal expansion coefficient. The low t hermalexpansion coefficient serves to provide a measureme ntindependentfrom a temperature change.The sensor element may be a fiber optic sensor. A f iber opticsensor is particularly suitable for use in high-vol tagecomponents because of the signal transmission by li ghtinstead ofelectriccurrents.The load cell housing may be formed from an insulat ingmaterial. As an example, the insulating material ma y be apolymericmaterial.The insulating materialallows the load P2024,0794 WO N / P230232WO01 September30,2025 -4 -cell to be positioned near electrically active comp onents ofthe transformer.The load cell housing comprises an upper portion an d a lowerportion, wherein the measuring portion is positione d betweenthe upper portion and the lower portion. The measur ingportion expands when a compressive force is applied betweenthe upper portion and the lower portion. Each of th e upperportion and the lower portion may comprise a plate- shapedportion. The upper portion and the lower portion ma y beformed from a rigid material. The upper portion and the lowerportion may comprise plain outer surfaces. It is al sopossible that the outer surface of the upper portio n and / orthe lower portion is slightly curved. The axial for ces to bemeasured may act on the outer surfaces. The upper p ortion andthe lower portion ensure that the load is distribut ed evenlyin the load cell. The load cell may be a two-part h ousing,formed bythe upperportion and the lowerportion.The supporting structure may form the connection be tween theupper portion and the lower portion. The connection may beconstantly provided by the supporting structure, i. e., alsowhen no compressive force isapplied.The supporting structure may provide formation of a gapbetween areas of the upper portion and the lower po rtion. Thegap may be laterally adjacent to the supporting str ucture.The gap may separate areas of the upper portion and the lowerportion from each other.The supporting structure serves to adjust the force s actingon the measuring portion and / or the sensor when a c ompressionforce acts on the load cell housing. Thereby an exc essive P2024,0794 WO N / P230232WO01 September30,2025 -5 -force on the measuring portion and / or the sensor ca n beavoided. As an example, the structure, extension an d / ormaterial of the supporting structure may be adjuste d toarrive ata desired range offorce.The supporting structure may be integrally formed w ith thelower portion and / or or the upper portion. It is al sopossible that the supporting structure may be provi ded as oneor more separate parts and assembled with the lower portionand the upperportion.The supporting structure may surround the measuring portion.Asan example,the supporting structure mayhave a circular,oval or rectangular shape enclosing the measuring p ortion, inparticular may be formed as a circular ring or a re ctangularframe enclosing the measuring portion. A rectangula r shapeincludes a shape of a square. The supporting struct ure may becircumferentiallycontinuousorinterrupted.Itis alsopossible that the supporting structure is formed by aplurality of separate elements with gaps formed bet ween theelements. As an example, the supporting structure m ay beformed by a plurality of pillars. The supporting st ructuremay take up a defined amount of compressive force i n an areasurrounding the measuring portion.The measuring portion and the sensor may be provide d as partsof a sensing element assembled with the load cell h ousing.The sensing element may be shaped as a disc, for ex ample.It is also possible that the measuring portion is p rovided inthe shape of a pillar. As an example, the measuring portionmay be provided as a central pillar and the support ing P2024,0794 WO N / P230232WO01 September30,2025 -6 -structure may be provided as further pillars surrou nding thecentralpillar.According to a further aspect, a transformer compri ses a loadcell for measuring forces acting in the transformer . The loadcell may comprise any structural and functional fea tures ofthe load cell described in the foregoing. The trans former maycomprise atleastone winding wound around a core. The loadcell may be configured for measuring forces in an a ctive partof the transformer. The forces may be axial winding forces,for example. The load cell may be positioned near t he top orbottom of winding. As an example, the load cell may bepositioned between a clamping system and the windin g.According to a further aspect, a method for manufac turing aload cellisdisclosed.The load cellmaycomprise anystructural and functional characteristics of the lo ad celldescribed in the foregoing. The method comprises pr oviding anupper portion, a lower portion, a measuring portion and asensor, arranging the measuring portion and the sen sor on thelower portion or on the upper portion and assemblin g theupper portion with the lower portion. The supportin gstructure may be an integral part of the lower port ion and / orthe upper portion or may be assembled with the lowe r portionand / orthe upperportion.The present disclosure comprises several aspects an dembodiments. Every feature described with respect t o one ofthe aspects and embodiments is also disclosed herei n withrespectto the otheraspectsand embodiments,even iftherespective feature is not explicitly mentioned in t hiscontext. P2024,0794 WO N / P230232WO01 September30,2025 -7 -Further features, refinements and expediencies beco meapparent from the following description of the exem plaryembodimentsin connection with the figures.In the figures,elements of the same structure and / or functionality may bereferenced by the same reference signs. It is to beunderstood that the embodiments shown in the figure s areillustrative representations and are not necessaril y drawn toscale.Figure 1A shows an embodiment of a load cell in a p erspectivesectionalview,Figure 1B shows the load cell of Fig. 1A in a disas sembledview, Figures2A-2D show stepsin manufacturing the load cellof Fig.1A,Figure 3A shows a further embodiment of a load cell in ain a partiallydisassembled,perspective view,Figure 3B shows a lower portion of the load cell of Fig. 2A,Figure 3C shows an upper portion of the load cell o f Fig. 2A,Figures4A,4B and 4C show a furtherembodimentof a load cellin perspective view,a longitudinalsectional view and a crosssectionalview,Figure 5 shows an embodiment of a transformer compr ising aload cell. P2024,0794 WO N / P230232WO01 September30,2025 -8 -Figures 1A and 1B show an embodiment of a load cell 1 for atransformerin a perspective sectionalview and an explodedview, respectively. The load cell1 may be configure d formeasuring forces in an active part of the transform er. Thetransformer may be a large power transformer, for e xample.The transformer may be a three-phase transformer, w ith a corecomprising three limbs, wherein the windings for ea ch phaseare wound around one ofthe limbs.The load cell 1 comprises a load cell housing 2, in which asensing element 3 is positioned. The sensing elemen t 3comprises a deformable measuring portion 4 and a se nsor 5 formeasuring the deformation ofthe measuring portion 4.In theshown embodiment, the measuring portion 4 extends i n a planeperpendicular to a z-axis when compressive forces a ct on theload cell1 and,therebyon the sensing element3, along the z-axis.The sensor 5 may be a fiber optic sensor. A fiber o pticsensor is particularly suitable for use in high-vol tagecomponents because the signals are transmitted by l ight andnot be electric currents. The fiber optic sensor ma y be aninterferometric-based sensorsuch asa Fabry-Perotinterferometric sensor. Such an interferometric-bas ed sensormay comprise two dielectric mirrors and a cavity in -betweenthe mirrors, wherein light is reflected at both mir rors andan interferometric path length difference between t hereflected light is determined. When the measurement portionand, thereby, the sensor portion attached to the me asurementportion expands, the cavity length between the diel ectricmirrors increases. In particular, the sensor may us e WhiteLight Polarization Interferometry (WLPI) for detect ingchanges in the measuring portion 4. Such a sensor a llows P2024,0794 WO N / P230232WO01 September30,2025 -9 -temperature-independent measurements. It is also po ssible touse a Fiber Bragg Grating Sensor that uses the prin ciple ofBragg diffraction formeasuring a deformation.In the shown embodiment, the sensing element 3 is p rovided asa separate element and is assembled with the load c ellhousing 2 for forming the load cell 1. It is also p ossiblethat the measuring portion 3 is integrally formed w ith theload cell housing 2. The sensor 5 can be embedded i n the loadcellhousing 2. The load cellhousing 2 ismade from an insulating materialto ensure electrical insulation and enable position ing theload cell housing 2 in the active part of a transfo rmer. Asan example, the insulating material may be a polyme ricmaterial. Furthermore, the material may be suitable for oil-immersion.The sensing element 3 has the shape of a disc compr ising anupper part 6, a lower part 7 and a membrane part, w hich formsthe measuring portion 4. The upper part 6, the meas uringportion 4 and the lower part 7 are connected to eac h othercircumferentially.The upperpart6,the measuring portion 4and the lower part 7 have a distance from each othe r in acentral section. When the sensing element 3 is axia llycompressed, the centers of the upper part 6 and the lowerpart 7 move towards each other, causing an extensio n of themeasuring portion 4 in the x-y-plane, perpendicular to the z-axis. This extension is measured by the sensor 5. W hen theaxial force is removed or reduced to its original v alue, thesensing element 3 elastically returns to its origin al shape. P2024,0794 WO N / P230232WO01 September30,2025 -10 -The parts of the sensing element 3 may be electrica llyinsulating.Asan example,a ceramicmaterialsuch asalumina isused. The sensing element3 isembedded in the load cell housing 2.The load cell housing 2 protects the sensing elemen t 3 and,thereby the measuring portion 4 and the sensor 5 fr om beingdamaged byexcessive compression forces. The load cellhousing 2 hasan upperportion 8 and a lowerportion 9. The sensing element 3 is positioned betw een theupper portion 8 and the lower portion 9, in a reces s 10formed in the upper portion 8 and the lower portion 9. Boththe upper portion 8 and the lower portion 9 have th e shape ofa plate with plan outersurfaces11,12.The upper portion 8and the lower portion 9 are rigid to ensure that th e load isdistributed evenly in the load cell 1. As an exampl e, theload cell housing 2 ensures that the sensing elemen t 3experience forcesonlyalong the z-axisand notin adirection oblique to the z-axis. Thereby, a correctfunctioning and precise measurement in different bo undaryconditionsisensured.The load cell housing 2 comprises a supporting stru cture 13being positioned between the upper portion 8 and th e lowerportion 9 and forming the connection between the up perportion 8 and the lower portion 9. In the shown emb odiment,the supporting structure 13 is in the shape of a ri ng andforms a raised part of the lower portion 9. The upp er portion8 comprises a recess 14 for positioning the support ingstructure 13. The recess 14 has a smaller height th an thesupporting structure 13 such that the supporting st ructure 13 P2024,0794 WO N / P230232WO01 September30,2025 -11 -is not fully embedded in the recess 14 but merely m aintainedin itsposition. The supporting structure 13 isan integralportion ofthelower portion 9. It is also possible that the suppo rtingstructure 13 isa separate elementand attached to the lowerportion 9. Furthermore, it is also possible that th e upperportion 8 comprises the raised supporting structure 13 orthat both the upper portion 8 and the lower portion 9comprise a raised supporting structure 13.The supporting structure 13 may comprise the same m aterial ora different material than the upper portion 8 and t he lowerportion 9. The supporting structure 13 may comprise amaterial with a higher compressibility than the upp er portion8 and the lowerportion 9.The supporting structure 13 encircles the sensing e lement 3and is adjacent to the recess 10 for the sensing el ement 3.The supporting structure 13 does not extend to a la teral areaof the load cell housing 2. Thereby, a circumferent ial gap 15exists between the upper portion 8 and the lower po rtion 9.The gap 15 is unfilled. The gap 15 may be filled byinsulating liquid when positioned in a transformer. Thesupporting structure 13 can be also denoted as a sp acingstructure for providing a defined spacing between t he upperportion 8 and the lowerportion 9.When a compressive force is applied between the upp er portion8 and the lower portion 9 along the z-axis, the sup portingstructure 13 is pressed towards the upper portion 8 and takesup a defined amount of the compressive force. There by, thecompressive force acting on the sensing element 3 c an be P2024,0794 WO N / P230232WO01 September30,2025 -12 -calibrated by the extension and compressive charact eristicsof the supporting structure 13. The compressive for ce can becalibrated such that the force applied to the sensi ng element3, and thereby to the measuring portion 4, is suffi cient toallow a precise measuring while a destruction of th e sensingelement3 willbe prevented.The signals provided by the sensor 5 can be registe red by atransducer, transferring the optical signals to ele ctricalsignals. The transducer may be capable of measuring signalsofatleast1 kHz.A data processing algorithm can thentranslate the strain measurement data into forces a pplied onthe load cell1.Figures 2A-2D show steps in a method of manufacturi ng theload cellofFigs.1A and 1B.Fig. 2A shows the lower portion 9 provided as a sep aratepart. Fig. 2B shows the upper portion 8 provided as aseparate part.Fig.2C showsthe sensing element3 provided asa separate part. Fig.2D showsthe sensing element3 assembled with the lowerportion 9. The sensing element 3 is positioned in t hecircular recess 10 of the lower portion 9. After th at, theupper portion 8 is assembled with the lower portion 9.Figures 3A, 3B and 3C shows a further embodiment of a loadcell 1 in disassembled views. The embodiment is lik e theembodiment of Fig. 1A but differs in the shape of t he upperportion 8, the lower portion 9 and the supporting s tructure13. P2024,0794 WO N / P230232WO01 September30,2025 -13 -Fig. 3A shows a lower portion 8 with a sensing elem ent 5positioned in a central recess 10. The sensing elem ent 5 canbe configured as in the preceding embodiments. Fig. 3B showsthe lower portion 8 provided as a separate part bef oreassemblywith the sensing element5.Fig.3C shows the upperportion 8 as a separate part before assembly with t he lowerportion 9. The assembly of the parts corresponds to theassemblydisclosed in Figs.2A to 2D.In this embodiment, the upper portion 8 and the low er portion9 have a rectangular shape. The load cell housing 2 thus hasa shape of a rectangular plate. The recess 10 for p ositioningthe sensing element 3 has a rectangular circumferen ce.However,itisalso possible to provide a circular recessas in the foregoing embodiment.The supporting structure 10 circumferentially surro unds thesensing element 3. In contrast to the foregoing emb odiment,the supporting structure 10 is formed from a plural ity ofpillars. Furthermore, the supporting structure 10 i s arrangedin the shape of a rectangle, near the circumference of theload cellhousing 2.The upper portion 8 comprises a plurality of recess es forpartially accommodating the pillars. Also in this e mbodiment,the supporting structure 10 ensures that the load c ellhousing 2 is provided with a gap 15 between the upp er portion8 and the lower portion 9. In this case, a gap 15 i s locatedbetween the pillars of the supporting structure 10.Furthermore, the gap 15 extends also circumferentia lly at alateraledge ofthe lowerportion 8. P2024,0794 WO N / P230232WO01 September30,2025 -14 -Also in this embodiment, the compression force acti ng on thesensing element 15 can be adjusted by the supportin gstructure 13. As an example, the number of pillars, theextension of the pillars and the material of the pi llars canbe selected. Figures4A,4B and 4C show a furtherembodimentof a loadcell 1 in perspective view, a longitudinal sectiona l view anda cross sectional view, respectively. The cross-sec tionalview of Fig. 4C is at the position indicated with A —A in Fig.4B. Also in thisembodiment,the load cell1 comprises a load cellhousing 2 with an upperportion 8 and a lower portion 9.The upper portion 8 and the lower portion 9 have pl ain outersurfaces 11, 12 and are in the form of rigid plates . Theoutersurfaces11,12 maybe also slightlycurved.The load cell 1 has a supporting structure 13 forme d as aplurality of pillars, wherein gaps are provided bet ween thepillars. The pillars are arranged in the form of se veral rowsand columns. A gap 15 is provided between the pilla rs and,thus, also between the upper portion 8 and the lowe r portion9. In this embodiment, the gap 15 does not extend i n alateral edge region but the supporting structure 13 reachesthe lateral edge. The material of the load cell hou sing 2 maybe the same asin the foregoing embodiments.A measuring portion 4 is formed as a central pillar . Thecentral pillars can be of the same structure and ma terial ofthe pillars of the supporting structure 13 which en circle thecentral pillars. It is also possible that the centr al pillars P2024,0794 WO N / P230232WO01 September30,2025 -15 -has a different structure and / or a different materi al thanthe supporting structure 13.A sensor 5 is positioned at or near or inside the m easuringportion 4 for measuring the deformation during appl ication ofan axialcompressive force on the load cell1.The measuringportion 4 may comprise a recess for positioning the sensor 5.The sensor 5 may measure an extension of the measur ingportion 4 in a lateraldirection.The sensor 5 may be a fiber optic sensor with a con nector 16to a transducerand a data acquisition system.The connector16 may be a fiber optic connector. A similar connec tor 16 maybe presentalso in the otherembodiments.Also in this embodiment, the supporting structure 1 3determines the forces acting on the measuring porti on 4 andthe sensor5.The numberofpillars,the extension ofthepillars and the material of the pillars can be sele cted toachieve a desired compressive force. The supporting structure 13 maybe attached to the lowerportion 8 and the upper portion 9. It is also possi ble thatthe supporting structure 13 is integral with the lo werportion 8 and / orthe upperportion 9.In manufacturing the load cell 1, the upper portion 8, thelower portion 9 and the sensor 5 may be provided. A Centralpillar for forming the measuring portion 4 may be a ttached tothe lower portion 9. The sensor element 5 can be at tached tothe measuring portion 4 before attaching the measur ingportion 4 to the lower portion 9 or thereafter. The n, thefurtherpillarsofthe supporting structure 13 are attached P2024,0794 WO N / P230232WO01 September30,2025 -16 -to the lower portion 9. As the last step, the upper portion 8isattached to the supporting structure 13.In a further embodiment, a sensing element 3 as sho wn in Fig.2C can be located at the center of the load cell ho using 2instead ofthe pillar-shaped measuring portion.Figure 5 shows a transformer active part 100 compri sing aload cell 1 for measuring axial forces. The transfo rmer maybe a power transformer. The transformer active part 100 maybe positioned in a tank filled with an insulating l iquid. Thetransformer is a three-phase transformer, with a co re 101comprising three limbs and windings 102 wound aroun d each ofthe limbs.The load cell 1 may be positioned between a beam 10 3positioned above or below a winding 102 and the win ding 102.The beam 103 may be part of a clamping system for c lampingcomponentsofthe transformeractive part100 such asthewindings 102 and the core 101. The load cell 1 is c onfiguredto measure winding axial forces which may occur dyn amicallyduring short circuiting or static axial forces exer ted by theclamping system on the windings 102. Also other axi al forcessuch as core forces or clamping forces may be measu red by theload cell1.The load cell 1 may be also positioned at other pos itions.For example, the load cell 1 may be positioned with in one ofthe windings 102 or above the upper ones of the bea ms 103 orbelow the lower ones of the beams 103. It is also p ossiblethat a load cell 1 is provided for each of the phas es. P2024,0794 WO N / P230232WO01 September30,2025 -17 -Reference Signs1 load cell 2 load cellhousing 3 sensing element 4 measuring portion 5 sensor 6 upperpartofsensing element 7 lowerpartofsensing element 8 upperportion ofload cellhousing 9 lowerportion ofload cellhousing 10 recessforsensing element 11 outersurface upperportion 12 outersurface lowerportion 13 supporting structure 14 recessforsupporting structure 15 gap 16 connector 100 transformeractive part 101 core 102 winding 103 beam z axialdirection

Claims

P2024,0794 WO N / P230232WO01 September30,2025 -18 - Claims1. A load cell (1) for measuring forces in a transf ormer,comprising a measuring portion (4) and a sensor (5) formeasuring a deformation of the measuring portion (4 ), whereinthe sensor (5) is attached to the measuring portion (4),and comprising a load cellhousing (2),wherein the measuring portion (4) and the sensor (5 ) isembedded in the load cellhousing (2),wherein the load cell housing (2) comprises an uppe r portion(8)and a lowerportion (9),wherein the measuring portion(4) is positioned between the upper portion (8) and the lowerportion (9), wherein the measuring portion (4)isconfigured to expandwhen a compressive force is applied between the upp er portion(8)and the lowerportion (9),wherein the load cell housing (2) comprises at leas t onesupporting structure (13) for limiting a force exer ted on themeasuring portion (4), wherein the supporting struc ture (13)formsthe connection between the upperportion (8) and the lowerportion (9). 2.The load cell(1)ofclaim 1, wherein the sensor(5)isa fiberopticsensor. 3.The load cell(1)ofclaim 2, wherein the sensor(5)isan interferometric-based sensor.

4. The load cell (1) of any of the preceding claims ,wherein the measuring portion (4) and the sensor (3 ) areparts of a sensing element (3) assembled with the l oad cellhousing (2). 5.The load cell(1)ofclaim 4,P2024,0794 WO N / P230232WO01 September30,2025 -19 - wherein the sensing element(3)comprisesan upper part(6)and a lower part (7) configured to be pressed towar ds eachother by a force exerted on the load cell housing ( 2),wherein the measuring portion (4) is located betwee n theupperpart(6)and the lowerpart(7).

6. The load cell (1) of any of the preceding claims ,wherein the load cell housing (2) is formed from aninsulating material.

7. The load cell (1) of any of any of the preceding claims,wherein the measuring portion (4) comprises a ceram icmaterial.

8. The load cell (1) of any of the preceding claims ,wherein each of the upper portion (8) and lower por tion (9)comprisesa plate-shape.

9. The load cell (1) of any of the preceding claims ,wherein the supporting structure (13) provides form ation of agap (15) in areas between the upper portion (8) and the lowerportion (9).

10. The load cell (1) of any of the preceding claim s,wherein the supporting structure (13) is an integra l part ofthe upper portion (8) and / or the lower portion (9).

11. The load cell (1) of any of the preceding claim s,wherein the supporting structure (13) surrounds the measuringportion (4).

12. The load cell (1) of any of the preceding claim s,P2024,0794 WO N / P230232WO01 September30,2025 -20 -wherein the supporting structure (13) has a circula r, oval orrectangularshape.

13. The load cell (1) of any of the preceding claim s,wherein the supporting structure (13)isformed by a pluralityofpillars.

14. The load cell (1) of any of the preceding claim s,wherein the load cell housing (2) is a two-part hou sing,formed by the upper portion (8) and the lower porti on (9).

15. A transformer comprising the load cell (1) of a ny of thepreceding claims, wherein the transformer comprises at leastone winding (102) wound around a core (101), wherei n the loadcell (1) is configured for measuring forces in a tr ansformeractive part(100). 16.The transformerofclaim 15,wherein the load cell (1) is configured for measuri ng axialforces within a winding (102) or for measuring axia l forceswithin a clamping system or for measuring axial for cesbetween a winding (102) and a clamping system of th etransformeractive part(100). 17.A method formanufacturing a load cell(1)for a transformer,the load cell (1) comprising a deformable measuring portion(4) and a sensor (5) for measuring a deformation of themeasuring portion (4), and comprising a load cellhousing (2),wherein the measuring portion (4) and the sensor (5 ) isembedded in the load cellhousing (2),P2024,0794 WO N / P230232WO01 September30,2025 -21 -the load cell housing (2) comprising at least one s upportingstructure (10)forlimiting a force exerted on the deformable portion (4),the method comprising providing an upper portion (8 ) of theload cell housing (2), a lower portion (9) of the l oad cellhousing (2) and a sensing element (3) comprising th emeasuring portion (4) and the sensor (5) attached t o themeasuring portion (4),arranging the sensing element (3) on the lower port ion (9)and assembling the upper portion (8) with the lower portion(9) such that the measuring portion (4) is configur ed toexpand when a compressive force isapplied between the upperportion (8) and the lower portion (9) and such that thesupporting structure (13) forms the connection betw een theupper portion (8) and the lower portion (9).

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