Current distribution assembly with interface module for an electric conductor

Abstract

The invention relates to a current distribution assembly comprising an interface module and an electric conductor, extending along a longitudinal axis, connected to the interface module, wherein the interface module comprises an interface module base, the interface module base comprising a contact area, the contact area establishing 5 an electric connection between the interface module and the electric conductor, and wherein the electric connection is part of an electric current path from the interface module into a current conducting material of the electric conductor.

Description

CURRENT DISTRIBUTION ASSEMBUY WITH INTERFACE MODUEE FOR AN ELECTRIC CONDUCTORField of the invention

[0001] The present disclosure relates to electrical conductors and interface modules for connecting electrical conductors to electrical components, and more particularly to a current distribution assembly comprising an interface module and an electric conductor, and an electric system comprising an interface module connected to an electric conductor.Background of the invention

[0002] Power tubes are known in the art from GB424215. Here tubular conductors having a standard outer perimeter are disclosed. These conductors are terminated in cable shoes, which in context of the present invention could be referred to as interface modules.

[0003] Tubular conductors are also known from high voltage installations.Summary of the invention

[0004] The inventors of the present invention have found that a need of conductors and in particular for tubular conductors having different outer and inner perimeters exist. Thus, the inventors have found that an interface module suitable for adapting to various sizes are needed.

[0005] Therefore, the inventors have provided a current distribution assembly comprising an interface module and an electric conductor, extending along a longitudinal axis, connected to the interface module, wherein the interface module comprises an interface module base, the interface module base comprising a contact area, the contact area establishing an electric connection between the interface module and the electric conductor, and wherein the electric connection is part of an electriccurrent path from the interface module into a current conducting material of the electric conductor.

[0006] As used herein, the term 'current distribution assembly' refers to an assembly comprising at least an interface module and an electric conductor connected thereto, wherein the interface module and the electric conductor together form a current path for conducting electric current. The current distribution assembly may also be referred to as a conductor assembly.

[0007] Such interface module is advantageous in that it has the effect, that it can be releasably mounted to the electric conductor and can thus be removed again after connection without damaging the electric conductor. This is at least true when the contact area follows the outer perimeter of the electric conductor or the inner perimeter of the electric conductor (if the electric conductor is hollow). The connection between the interface module and the electric conductor may be provided by bolts and nuts as will be explained below. A releasable mounting is advantageous in relation to production and service.

[0008] Such interface module is advantageous in that it has the effect, that e.g. a welding seem can be provided on the contact area in case the cross-sectional area of the contact area is larger than the cross-sectional area of the electric conductor.

[0009] A system comprising an interface module and an electric conductor according to the present invention is advantageous in that the termination of the electric conductor can be a standard termination. The interface module is then providing the interface i.e. the specific electric connection needed between the electric conductor and the electric component it is to be connected to.

[0010] The electric conductor may in principle be any type of conductor such as any massive or hollow conductors having any geometry. With this said typically the geometry of an electric conductor is cylindrical or square. The electric conductor extends along a longitudinal axis, which may be understood as the axis along the length of the conductor in the direction of current flow.

[0011] An interface module connected to the end of or inside a tubular electric conductor (sometimes referred to as simply as connector) is advantageous in that it has the effect that no pressing tools are needed to mount the interface module on the hollow tubular conductor. Thereby there is no risk for deforming the tubular conductor when mounting the interface module leading to a uniform connection from an electric point of view i.e. a more uniform connection compared to known methods of connecting interface modules and tubular electric conductors.

[0012] Further, connecting contact area of the interface module to the end or inside a tubular conductor is advantageous in that it can be mounted to an insulated conductor without first spending time on removing the insulation with the associated risk of damaging the electrically conducting material.

[0013] Further, connecting a contact area of the interface module to the end or inside a tubular conductor is advantageous in no further space is required for mounting the two together. Further, the system including such connection can be made more compact.

[0014] The interface module is a standalone module that is designed and produced to be used to be connected to an electric conductor such as a tubular electric conductor. A tubular electric conductor has an inner diameter and outer diameter at the point of connection. Hence, the interface module is not just e.g. a hole in the conductor and not a standard cable shoe that is to be place around the outer perimeter of a conductor for then being connected by a pressing tool. Once connected to the conductor, the interface module facilitates connection to an electrical component such as a further conductor, a switch gear, power module, etc.

[0015] The current path through a conductor of the present invention is defined by a current conducting cross-sectional area defined between an inner perimeter and an outer perimeter. The inner and outer perimeter do not need to be completely spherical, oval or whatever design the conductor has. In case of a hollow elongated cylindrical design the inner and / or outer perimeter may not follow a perfect circle. Hence, recesses or protrusions may partially define one or both of the inner and outerperimeter. In case of recesses or protrusions on or in the inner or outer perimeter, then inner and outer perimeter are measured between two points thereon which have no such recesses or protrusions.

[0016] The current conducting cross-sectional area is preferably made of copper or of aluminium in that they provide the best trade-off between cost and internal resistivity to electric current.

[0017] In an embodiment, the contact area defines a conductor interface plane and wherein the longitudinal axis of the electric conductor is perpendicular to the conductor interface plane when the interface module is electrically connected to the electric conductor.

[0018] This embodiment may be advantageous in that a tubular conductor can be connected directly to a terminal of an electric component via one single interface module, which reduces the number of connections and thereby reduces electric losses. Furthermore, having the longitudinal axis of the electric conductor substantially perpendicular to the conductor interface plane may simplify the mechanical design and assembly process, as the interface module can be aligned in a straightforward manner with the end of the conductor. This perpendicular arrangement may also provide a more uniform distribution of contact pressure across the contact area, potentially improving the reliability and consistency of the electrical connection.

[0019] In some embodiments, the longitudinal axis of the electric conductor may be oriented at an angle close to 90 degrees relative to the conductor interface plane, such as angles between 85 and 95 degrees. Such arrangements may still provide the benefits of simplified mechanical design and uniform contact pressure distribution across the contact area.

[0020] In an embodiment, the current path in the electric conductor comprises one or more branches defined by one or more grooves, and wherein the one or more grooves are provided into the current conducting material of the electric conductor.

[0021] This embodiment may be advantageous in that the grooves define branches in the current path, allowing the total current to be divided into current fractions conducted by these branches. By controlling the design of the grooves, it is possible to control how the current is conducted through the conductor. This may result in a more uniform distribution of current density across the cross-sectional area of the conductor, thereby optimizing the usage of current conducting material. Furthermore, the grooves may help mitigate the effects of skin effect and proximity effect, which can cause uneven current distribution and increased losses in AC systems. The provision of grooves may also enable a reduction in the cross-sectional area of the conductor while maintaining the same current carrying capacity, or alternatively allow higher currents to be conducted with the same cross-sectional area.

[0022] In an embodiment, the contact area of the interface module has a diameter that is less than or equal to an outer diameter of the electric conductor.

[0023] This embodiment may be advantageous in that the contact area can be aligned with the end face of the electric conductor, facilitating a direct and efficient electrical connection. When the diameter of the contact area is equal to the outer diameter of the conductor, the full cross-sectional area of the conductor can be utilized for current transmission at the interface. When the diameter is less than the outer diameter, the contact area may be configured to fit inside the conductor, enabling connection to the inner perimeter of a tubular conductor. This flexibility in sizing allows the interface module to accommodate various conductor geometries and connection configurations.

[0024] In an embodiment, the interface module is mounted to the electric conductor by bolts and nuts or by welding’s.

[0025] This embodiment may be advantageous in that bolts provide a releasable connection, allowing the interface module to be removed and replaced without damaging the electric conductor, which is beneficial for production and service. Welding provides a permanent and robust connection with low electrical resistance at the joint. Other equivalent methods of mounting may be used as alternatives to bolts and welding’ s, such as push and click lock systems, twist and lock systems, or threadedconnections, providing flexibility in selecting the most appropriate mounting method for a given application.

[0026] In an embodiment, the interface module and the electric conductor are monolithic.

[0027] This embodiment may be possible if the assembly is produced by additive manufacturing. A monolithic construction may be advantageous in that it eliminates the electrical resistance that would otherwise occur at the interface between separate components, thereby reducing electrical losses and heat generation at the connection. Furthermore, a monolithic design may provide improved mechanical strength and structural integrity, as there are no joints or fasteners that could loosen over time. Additive manufacturing enables the production of complex geometries that may be difficult or impossible to achieve with traditional manufacturing methods, allowing for optimized current paths and material distribution within the assembly. Suitable additive manufacturing techniques may include, for example, selective laser melting (SLM), electron beam melting (EBM), direct metal laser sintering (DMLS), wire arc additive manufacturing (WAAM), or binder jetting. In some embodiments, the monolithic interface module and electric conductor assembly may be formed from electrically conductive materials such as copper, copper alloys (e.g., CuCrlZr), aluminium, aluminium alloys (e.g., AlSilOMg), or other suitable electrically conductive metals. Process parameters such as layer thickness, laser power, and scan speed may be selected based on the material and desired properties of the finished assembly. In some cases, post-processing steps such as heat treatment, surface finishing, or machining of contact surfaces may be applied to achieve desired electrical and mechanical properties.

[0028] According to an embodiment of the invention, the contact area of the interface module has a first contact area distance between a first contact area point and a second contact area point, that is less than or equal to an outer conductor distance measured between a first conductor point and a second conductor point of the electric conductor.

[0029] According to an embodiment of the invention, the contact area of the interface module comprises a first contact area part and a second contact area part which together has a second contact area distance measured between a third conductor point and a fourth conductor point, that is less than an inner conductor distance measured between a third conductor point and a fourth conductor point.

[0030] The contact area points are defined on the (outer) perimeter of the contact area as the points between which the longest distance can be measured. Contact area points may be established independently of geometry of the conductor i.e. also on circular conductors.

[0031] Similarly, the conductor points defining the inner conductor distance are located on the inner perimeter of the conductor so that they define the longest distance between two points on the inner perimeter of the conductor. This is advantageous in that mounting of the interface module inside the conductor is facilitated.

[0032] Similarly, the conductor points defining the outer conductor distance are located on the outer perimeter of the conductor so that they define the longest distance between two points on the outer perimeter of the conductor. This is advantageous in that mounting of the interface module to the end of the conductor is facilitated.

[0033] In the situation where the conductor is a hollow elongated cylinder and the inner perimeter of a cross-sectional view of the conductor defines a circle, the inner conductor distance equals the diameter of the circle defined by the inner perimeter. In the same way, the first contact area distance equals the outer diameter of the contact area. This outer diameter may be defined by one or more contact area parts when these are connected.

[0034] According to an embodiment of the invention, the electrical conductor comprises inner fastening means.

[0035] According to an embodiment of the invention, the inner fastening means are threaded parts configured for receiving bolts.

[0036] Inner fastening means e.g. implemented as a threaded part such as a bolt or threat for receiving a bolt is advantageous in that it has the effect that the amount of material used for the connection of two conductor modules that is not used for current conduction is reduced. Inner fastening means may require that the conductor module has a hollow interior space for access to the bolts.

[0037] The connection of the interface module to the conductor may alternatively be made by push and click lock system, twist and lock systems, threaded parts in inner perimeter of the conductor and outer perimeter of a terminal rod facilitating screwing the two parts together, dowel, tongue and groove, the connection may be provided by heating and e.g. also with cold, etc.

[0038] Further it should be noted that the interface module and the conductor may be preassembled and thus received on site of use connected.

[0039] According to an embodiment of the invention, the electric conductor is a tubular electric conductor, and wherein the current conducting material is provided between an inner perimeter and an outer perimeter of the tubular electric conductor.

[0040] A tubular electrical conductor (also sometimes simply referred to as tubular conductor) should be understood as a conductor that has an inner and / or an outer perimeter with a hollow elongated design. The inner and outer perimeters may not need to be identical i.e. the outer shape / geometry may be different from the inner shape / geometry. Hence, the conductor may have a circular outer geometry and an oval inner geometry just to mention two different geometries of inner and outer perimeter. It should however be noted that the preferred embodiment of the conductor is in many applications a tubular design such as a hollow elongated cylinder.

[0041] According to an embodiment of the invention, the tubular electric conductor is a hollow elongated cylinder.

[0042] According to an embodiment of the invention, the contact area of the interface module has a diameter that is less than the inner diameter of the tubular electric conductor.

[0043] As the inner perimeter of the hollow elongated cylinder conductor defines a circle with an inner diameter, the contact area of the interface module also defines a circle with a diameter. This is to ensure optimal electric connection therebetween.

[0044] Connection of the contact area inside the conductor is advantageous in that it has the effect, that the area of contact between the interface module and the conductor can be increased for improved electric connection and mechanical stability / strength.

[0045] According to an embodiment of the invention, the contact area of the interface module comprises a terminal rod extending from the interface module base, wherein the interface module base defines an electric component plane.

[0046] A terminal rod is advantageous in that by such it is possible to adjust the length of the contact area between the inner perimeter of the conductor and the interface module. Thereby a primary current transmission area between the conductor and interface module can be established and adjusted.

[0047] Further, a terminal rod is advantageous in that by such it is possible to angle the surface of the interface module that is to be connected to an electric component and the contact area that is to be connected to the conductor relative to each other.

[0048] According to an embodiment of the invention, an angle is defined between a longitudinal center axis of the terminal rod and the electric component plane.

[0049] The angle between the center axis of the terminal rod and the electric component plane defined by the interface module base may be 90 degrees. In this situation, the center axis is perpendicular to the electric component plane, which means the center axis and the longitudinal axis of the conductor connected to the interface module are parallel to each other, i.e. the interface module does not provide any change of direction of the current path of the conductor. The angle may in principle have any angle, but in most cases, i.e. in most layouts of electric systems, a 90 degrees angle is preferred. Angles below 90 degrees such as down to 0 degrees may be used. A 0 degrees angle of the center axis of the terminal rod would mean the center axis isparallel to the electric component plane and thus would require a bend of the terminal rod before the center axis could be defined.

[0050] It should be noted that the electric component plane defined by the interface module base in principle can be found on both sides of the interface module base, just with different “Z-coordinate” in a Cartesian coordinate system.

[0051] According to an embodiment of the invention, the terminal rod has a length, measured from the interface module base, of at least 3cm

[0052] If not the conductor bend just before the part where it is mounted to the interface module, the terminal rod may in principle be as long as needed. The longer, the more contact areas between the conductor and the interface module. The length of the terminal rod may be relative to the outer diameter such that the length L is larger than the outer diameter divided by 3.

[0053] According to an embodiment of the invention, the terminal rod comprises an additional terminal rod part, wherein the additional terminal rod part is movable relative to the terminal rod.

[0054] When joint, the terminal rod and the additional terminal rod part may be referred to as a joint terminal rod.

[0055] According to an embodiment of the invention, the terminal rod and the additional terminal rod part has slope parts.

[0056] In some embodiments, the slope parts may comprise angled or tapered surfaces configured to engage with corresponding surfaces on the terminal rod or the additional terminal rod part. The slope surfaces may be oriented at an angle relative to the longitudinal axis of the terminal rod, such as an angle between 5 and 45 degrees, for example between 10 and 30 degrees. The slope surfaces may be planar, conical, or frustoconical in shape. In some cases, the slope parts may extend along a portion of the length of the terminal rod and / or the additional terminal rod part. When the terminal rod and the additional terminal rod part are forced together, for example by tightening a bolt and nut, the matching slope surfaces may slide relative to each other,thereby converting axial movement into radial expansion of the joint terminal rod. The angle and surface profile of the slope parts may be selected to provide a desired mechanical advantage and to control the rate of radial expansion relative to axial displacement.

[0057] The additional rod part being movable relative to the terminal rod is advantageous in that it makes the outer perimeter of the two rod parts flexible due to a sliding extension of the diameter of the joint terminal rod. Hence when forced together e.g. by a bolt and nut, the slope parts will force the outer perimeter of the joint terminal rod to increase. This leads to an increased diameter of the joint terminal rod. When expanded inside the conductor, this expansion will provide mechanical and electrical connection of the interface module and the conductor. Slope parts may also be referred to as a wedge part facilitating a wedge joint.

[0058] According to an embodiment of the invention, the slope part and / or the outer perimeter of the terminal rod and / or of the additional terminal rod part has a divergent surface matching a divergent surface of the inner perimeter of the tubular electric conductor.

[0059] A divergent surface is advantageous if it matches a divergent surface of the inner perimeter surface of the conductor. If matching divergent parts are provided, the connection between the two is optimized from an electric point of view.

[0060] According to an embodiment of the invention, the contact area further comprises an elevated contact area plane.

[0061] A planar contact surface provides a secondary current transmission area between the conductor and interface module which may be used for alignment before connection is established.

[0062] According to an embodiment of the invention, the terminal rod is hollow

[0063] Thereby it is possible to hide bolts used for connection. In addition, material usage is reduced, weight is reduced, and mounting is easy. Further, production can be optimized and it is dimensionally stabile in the moulding process.

[0064] According to an embodiment of the invention, the contact area defines a conductor interface plane at the end of the terminal rod.

[0065] As mentioned, a terminal rod may extend from the interface module base. This terminal rod may terminate in a contact area that is intended to be connected towards an end of the conductor i.e. not inside the conductor. This is advantageous in that tolerances of the terminal rod is higher than if the terminal rod should fit inside the conductor. Which is advantageous in production of the interface module.

[0066] Further, if the conductor is not hollow, attaching the interface module with the conductor interface plane towards the end of the conductor and not over the outer perimeter of the conductor is advantageous.

[0067] According to an embodiment of the invention, an angle is defined between the conductor interface plane and the electric component plane, wherein the angle is between 0 and 90 degrees.

[0068] Providing an interface module with an angle between one side, i.e. an interface towards an electric component to which the conductor is to be connected, and another side, i.e. the interface to the conductor, is advantageous in that it has the effect that a bend of the conductor can be made with a very short bending radius. This is advantageous in that it has the effect, that the footprint a system comprising a conductor comprising two conductor parts connected with an interface module of the present invention can be reduced. Further, by connecting two interface modules all angles between 0 degrees and 360 degrees can be made.

[0069] The angle may at least provide bend of the terminal rod between parallel and perpendicular positioning of the conductor connected to the interface module and the plane of the interface module base / electric component plane.

[0070] According to an embodiment of the invention, a contour of the contact area at the end of the terminal rod is defined by outer perimeter of the current conducting material of the electric conductor.

[0071] To make the interface module fit conductors having different outer perimeters i.e. following an outer contour, it is advantageous that the contact area then matches the contour of the conductor to which it is to be connected. Matching may also be understood as being larger than the conductor contour facilitating room for a welding seam.

[0072] According to an embodiment of the invention, one or more terminals holes are provided in the contact area and are aligned with one or more threaded parts of the electric conductor, wherein the contact area and the electric conductor are configured for being connected via one or more bolts through the terminal holes into the threaded part.

[0073] Having threaded parts inside the conductor is advantageous in that it has the effect that it facilitates mounting of the interface module against a cross-sectional area of the conductor.

[0074] Aligning terminal holes and terminal thread is advantageous in that it has the effect, that the two parts can be connected by bolts mounted from the interface module into the conductor. In this way mounting is facilitated between an interface module and a long and / or bending conductor in that no access to the interior of the conductor is needed.

[0075] Further, connecting the contact area of the interface module and a contact area of the conductor can be connected via terminal holes is advantageous in that an interface module can be connected to a conductor that has a very short liner part at its end. In fact, the terminal thread may extend into the current conducting material between the inner and outer perimeter and thereby facilitate mounting of an interface module to a conductor having limit distance or no distance at all that is linear towards its end.

[0076] According to an embodiment of the invention, at least part of the cross-sectional area of the electrical conductor and at least part of the contact area at the end of the terminal rod comprises a divergent surface.

[0077] A divergent surface or portion is advantageous in that it has the effect, that the electric connection therebetween is improved.

[0078] According to an embodiment of the invention, the interface module is a terminal interface module

[0079] A terminal interface module should be understood as a termination of a conductor with means, typically holes or threaded parts, for connecting the conductor to an electric component.

[0080] According to an embodiment of the invention, the interface module is a conductor connection interface module

[0081] A conductor connection interface module should be understood as an interface between two conductors. Such conductor interface module is advantageous in that it can change direction of the path of the conductor, extend a first conductor in a direction by connecting it to a second conductor, etc.

[0082] It should be noted that two conductors connected via an interface module of the present invention may not need to have the same cross-sectional area and may not need to have the same current conducting cross-sectional area.

[0083] According to an embodiment of the invention, the interface module is a conductor split interface module.

[0084] A split interface module should be understood as an interface module which at one side is connected to one conductor or one electrical component while at the other side is connected to two conductors or electrical components.

[0085] To facilitate this, the one side which could be the side defining the conductor interface plane comprises two contact areas each configured for being connected to one conductor. The two contact areas may define two different conductor interface plans i.e. being connectable to non-parallel conductors. On another side of the interface module one electric component plane may be defined via which the two conductors can be connected to an electric component such as a busbar, switch, etc.

[0086] It should be noted that preferably, no matter the type of interface module, the interface module is releasably connected to the conductor, such releasable connection may be facilitated by bolts and nut / internal threaded parts.

[0087] According to an embodiment of the invention, the interface module comprises a poka yoke element.

[0088] A poka yoke element is advantageous in that it has the effect, that it facilitates that the interface module can only be mounted in one way i.e. the correct way. A poka yoke element may require a matching or opposite poka yoke element or structure on the interface that it has to be connected to. Also, a poka yoke element may facilitate a certain turn or twist of two interface modules relative to each other.

[0089] A poka yoke element may be implemented as an irregular part of a structure such as an irregularity of a divergent surface, a cut corner, interrupted recess or protrusion, etc. that has a matching element on the part to which the interface module with poka yoke element is to be connected.

[0090] According to an embodiment of the invention, the electric conductor comprises one or more helix grooves in its inner perimeter or in its outer perimeter.

[0091] According to an embodiment of the invention, the electric conductor comprises one or more helix protrusions on its inner perimeter or on its outer perimeter.

[0092] Helix protrusions are advantageous in that it assists in controlling the current path through the conductor and thereby impact on self-impedance and mutual impedance e.g. from neighbouring conductors. Helix grooves or protrusions may be implemented as stepwise helix or continuous helix.

[0093] According to an embodiment of the invention, the electric conductor is comprised by an electric cabinet.

[0094] The electric conductor is particularly advantageous for high-power electrical systems, e.g. from lOkW and up, such as 22kW, 50kW, HOkW, 150kW, 225kW,300kW, 350kW, 500kW, 800kW, 1MW, 2MW, 3MW, or even higher, such as e.g.5MW or 10MW systems, with voltages of e.g. 110V, 230V, 400V, 690V, 800V, 1000V, 1500V, 6kV or e.g. lOkV, and currents from e.g. 16A, 32A or 64A, to several hundreds, e.g. 100A, 200A or 500A, or even thousands, e.g. 1000A to 5000A.

[0095] One or more conductors may be used for local connections inside such a high-power electrical system, e.g. contained inside an electrical cabinet housing a power converter, inverter, transformer, generator, electric motor, breaker, high-power battery system, battery charger, or similar power systems, possibly including capacitors, reactors or inductors, power resistors, dump loads, etc. A system, component or conductor may be categorized as a high-power system, component or conductor if it is operating at currents in the range of 500- 1000 A or higher.

[0096] Non-limiting examples of such electrical installations / systems include energy facilities such as grid components such as substations with grid support, voltage regulation, power to x plants, etc., energy generating systems such as wind turbines, wind farms, solar plants, etc., electric installations in a private homes and industry, industrial machines, household appliances, etc. and means for transportation such as airplanes, heavy duty vehicles, light duty vehicles such as automobiles, trains, ships, etc.

[0097] According to an embodiment of the invention, the electric conductor has an outer perimeter of at least 4cm.

[0098] As used herein, the outer perimeter refers to the circumference of the conductor, i.e., the total length measured around the outer boundary of the conductor's cross-sectional area. No matter if the conductor has a circular, square or other geometry that has a massive center or non-massive center it is advantageous to have an outer perimeter that is at least 4cm to be able to conduct the high currents indicated above. In fact, the perimeter may be significantly higher such as above 20cm. A large perimeter is typically rectangular conductors but not limited to this geometry. Hence, any perimeter between 4cm and 30cm would not be considered unusual.

[0099] It should be noted that it is the cross-sectional area of the current conducting material that is decisive for the number of amps a given conductor can conduct. Hence, the distance between the inner and outer perimeter of e.g. a tubular conductor may be relative to the skin depth. Hence, if the skin depth is 10mm and the outer diameter of the conductor is 100mm, the cross-sectional area may be pi*(50A2-40A2)= 2874mmA2.

[0100] According to an embodiment of the invention, the one or more helix grooves is implemented as air gaps.

[0101] A current separating effect of the grooves can be obtained by various implementation hereof. One is by providing an air gap from the outer perimeter of the conductor that extends into the electric current conducting material towards the center of the conductor. Alternatively, from the inner perimeter and outwards. Such groove can be filled with a material that complies with specific requirements to electric isolation. Such air gap can go all the way through the current conducting material of a conductor.

[0102] One such material is air which is advantageous in that it fills the groove as the groove is provided. Further, air is advantageous in that it is a free and can fill even the tiniest groove.

[0103] According to an embodiment of the invention, the one or more grooves separates the outer perimeter of the electric current conductor into a plurality of conductor branches.

[0104] By separating the outer or inner perimeter, a conductor module is provided that facilitates separating the total current into current fractions conducted by these branches. These fractions may be equal fractions. Thereby, the current fractions’ way through the conductor can be controlled by design of the grooves and thereby indirectly of the branches. Note that similar effect may occur if branches are made from grooves into the inner perimeter.

[0105] It should be noted that when referred to “the same” and “equal fraction” in this document, 100% similarity is difficult to reach and thus this should be understoodas a referred to ±5%. Hence, if 4 branches are provided, these are designed to each conductor 25% of the total current. This is considered achieved if ±5% of these 25% is conducted in each of the branches.

[0106] In an aspect, the invention relates to an electric system comprising an interface module connected to an electric conductor, the interface module comprises an interface module base, the interface module base comprising a contact area, the contact area being configured to establish an electric connection between the interface module and the electric conductor, wherein the electric connection is part of an electric current path from the interface module into a current conducting material of the electric conductor, and wherein the current path in the electric conductor comprises one or more branches defined by one or more grooves wherein the one or more grooves is provided into the current conducting material.

[0107] According to an embodiment of the invention, the invention relates to a system according to paragraph

[0106] , wherein the interface module and the electric conductor are defined by features of any one of the previous paragraphs

[0005] -

[0105] ,The drawingsFig. la and lb illustrates two embodiments of an interface module for connecting to a conductor,Fig. 2a-2d illustrates an interface module seen from two sides and a conductor for connecting to the interface module,Fig. 3a-3d illustrates an interface module seen from two sides and a conductor for connecting inside a conductor,Fig. 4a - 5b illustrates non-circular interface modules and conductors,Fig. 6a-6f illustrates various examples of interface modules and current distribution assemblies, andFig. 7 illustrates an example of a tubular conductor.Detailed description

[0108] Fig. la illustrates an interface module IM for connection to an tubular electric conductor PT (also referred to as a power tube). The interface module IM comprises an interface module base IMB. At the interface module base IM, a contact area CA is defined by the stipulated line. At least part of the contact area CA is configured for interfacing the conductor PT i.e. being the part of the interface module IM that is connected to the conductor PT. The illustrated contact area CA is designed to interface conductor having a diameter DIA. In this embodiment, the contact area CA is defined as part of the interface module base. Hence, a plane of the contact area and a plan of the interface module may be parallel and together be referred to as conductor interface plane CIP. The area of the contact area and the interface module base may in principle coincide as illustrated in fig. la.

[0109] The connection between the interface module and the conductor is in this embodiment implemented via four terminals holes TH provided in the contact area CA. Via these terminal holes TH the interface module and the conductor are connected by bolts and part of a current path is provided. The conductor may be provided with threaded parts for receiving the bolts or the terminal holes TH may be provided with threaded parts for receiving the bolts. The latter required that it is possible to access the interior of the conductor.

[0110] The illustrated interface module IM comprises electric conductor holes ECH. These are used to connect the conductor to an electric component once the interface module is connected to the conductor. It should be noted that the terminal holes and the electric conductor holes may be the same. In this situation the terminal holes TH may also simply be holes if the electrical component to which the conductor is to be connected comprises threaded parts for receiving bolts or it is possible to mount via a bolt from the electric component side.

[0111] As mentioned, the contact area CA of the interface module illustrated in fig. la is provided in a conductor interface plane CIP. Hence, the conductor interface planeCIP in this embodiment is defined at the side of the interface module base IMB where the conductor is connected while the other side of the interface module base IMB, where the electric component is connected, defines an electric component plane ECP. In the illustrated embodiment on fig. la, the conductor interface plane CIP is parallel to the electric conductor plane ECP.

[0112] It should be noted that the side of the interface module base defining the electric component plan ECP may, contrary to what is illustrated in fig. la, have a plane (flat) surface.

[0113] In fig. lb, the interface module of fig. la is provided with an elevated contact area ECA. In this way the conductor interface plane CIP, that is here raised from the interface module base IMB, may be referred to as an elevated conductor interface plane ECIP and configured for interfacing to the conductor and establishing a current path including both the interface module and the conductor. By raising the contact area and make the raised part hollow, it is possible to hide bolt heads inside the hollow part thereby hiding bolt heads inside the interface module IM between the electric component plane ECP and the elevated conductor interface plane ECIP.

[0114] In case the connection between interface module and the conductor is made via the end of the conductor i.e. that end being fixed to the contact area (elevated or not) it should be considered to optimize the electric interface e.g. via divergent portions on the contacting surfaces or by welding the two parts together to avoid a hot spot.

[0115] Alternative connections between interface module and conductor may be provided. One example hereof could be a tongue and groove joint and a furniture joint where e.g. the conductor comprises one or more dowels that fit holes in the interface module or vice versa. The dowels may comprise a threaded part perpendicular to the longitudinal axis of the dowel and a bolt may be provided through the interface module (or conductor) and into the dowel and in that way fastening the conductor to the interface module.

[0116] Fig. 2a illustrates an interface module IM according to the present invention seen from the conductor interface plane CIP. Fig. 2b illustrates the interface moduleof fig. 2a seen from the electric component plane ECP. Fig. 2c illustrates more details of the interface module of fig. 2a and fig. 2d illustrates a conductor PT to which the interface module IM is designed to be connected to.

[0117] The interface module IM of fig. 2a comprises, as the embodiment of fig. la, an interface module base IMB, conductor interface and electric component planes CIP, ECP and terminal and electric components holes TH, ECH. The only difference to the embodiment illustrated in fig. la is that the contact area CA in the embodiment illustrated in figures 2a, 2b and 2c is provided at a terminal rod TR. As illustrated, the contact area CA has a diameter DIA that is equal to or less than an outer diameter OD of the tubular electric conductor PT of Fig 2d.

[0118] A terminal rod TR is elevating and in this embodiment also angling the contact area CA. The elevation of the contact area CA is however not a parallel displacement of the contact areas as will be described below in relation to fig. 2c.

[0119] From fig. 2b it is possible to see that the terminal rod TR may be hollow. Being hollow allows for mounting of the interface module IM to the conductor PT from the inside of the terminal rod TR. In this way, the bolt heads are hided away and thus do not interfere with the electric component plane ECP. This allows for first mounting of the conductor PT to the interface module IM and then mount this assembly to an electric component

[0120] The electric component plane in this embodiment comprises a divergent surface i.e. a surface that is non-planar. A non-planar surface, when matched with a patter of the surface of the part that it is going to be connected to, is advantageous in that it optimizes the electric connection between the two parts. This is because by design of the matching divergent surfaces the force needed to connect the two can be reduced as well as the area of contact between the two surfaces is increased. Together this result in a reduced ohmic resistance and thereby reduced losses (heat generation). The required force is reduced because the forces acting between the two are component of the force from the bolt used to tighten the two together.

[0121] Fig. 2c illustrates the interface module IM of figures 2a and 2b in further details. Especially, fig. 2c illustrates the relationship between the plane defined by the contact area CA i.e. the conductor interface plane CIP and the electric contact plane ECP.

[0122] In this embodiment, the terminal rod TR has a center axis CAX. Thus, an angle Ax between this center axis CAX and the electric contact plane ECP defines the angle of the contact area CA at the end of the terminal rod TR. Hence if the angle Ax is 90 degrees, the conductor interface plane CIP of the contact area CA is parallel to the electric contact plane ECP and thus a conductor connected to an electric component via the interface module will continue from the electric conductor in a straight line.

[0123] Hence, the conductor interface plane CIP may be perpendicular to the center axis CAX and the the angle AX and the angle A between the conductor interface plane CIP and the electric contact plane ECP may be identical.

[0124] Terminals of many electric components are designed to be connected by a conductor leaving the electric component in a straight line or perpendicular. With the interface module of the present invention, such conductor may be connected to another conductor via two 45 degrees interface modules and thereby forming a 90 degrees bend of the connected conductors. Alternatively, an interface module may be designed with a customized angled terminal rod and thereby increasing the freedom in layout of the electric system e.g. in an electric cabinet.

[0125] The angle A between the contact area CA and thus the conductor interface plane CIP and the electrical component plane ECP may in principle have any value between 0 degree and 90 degrees both included. A 0 degrees angle will provide a parallel conductor interface plane CIP and electrical component plane ECP. A 90 degrees angle will provide a conductor interface plane CIP perpendicular to the electrical component plane ECP.

[0126] With interface modules having angles A of 15, 30 and 45 degrees most relevant bends of current paths in electric systems provided by conductors can beestablished. But it should be mentioned that the angle can be made system specific and thereby in principle any value between 0 and 180 degrees.

[0127] As the terminal rod TR extends from the interface module base IMB, it has a length. The length L of the terminal rod TR may be defined as the longest distance between where the terminal rod starts at the interface module base IMB and the contact area CA. This length L follows the outer perimeter of the terminal rod TR in a straight line between two points Pl (at the interface module base IMB where the terminal rod starts) and P2 (at the outer perimeter of the contact area CA). The length L of the terminal rod is defined as the shortest distance between the two points Pl and P2.

[0128] Fig. 2d illustrates a conductor PT connectable to an interface module according to an embodiment of the invention. The illustrated conductor PT has an outer perimeter OP defining an outer diameter OD of the conductor. This outer diameter is in the illustrated embodiment equal to the diameter DIA of the contact area CA at the end of the terminal rod TR of fig. 2c.

[0129] The conductor PT is illustrated as a tubular conductor and has therefore also an inner perimeter IP defining an inner diameter ID. Traveling around the inner perimeter of the conductor, the inner perimeter defines a threaded parts TP for receiving bolts from the interface module. Finally, the conductor PT is illustrated with a groove G. A conductor with a groove will briefly be explained below.

[0130] Fig 3a illustrates an interface module IM that comprises a terminal rod TR on an elevated contact area ECA configured for being mounted to a conductor PT inside the conductor PT against its inner perimeter IP.

[0131] The interface module comprises an interface module base IMB comprising electric component holes ECH via which the interface module base can be connected to an electric component.

[0132] The terminal rod TR is extending from and in this embodiment also perpendicular to the interface module base IMB. In this embodiment, the contact area CA is partly defined on the outer perimeter of the terminal rod TR and partly as theconductor interface plane CIP of the elevated contact area ECA. Hence, the contact area in this interface module is partly perpendicular to the interface module base IMB and partly parallel to the interface module base IMB. When mounted, the conductor is thereby perpendicular to terminals of the electric component to which the interface module / conductor is connected to.

[0133] Together with an additional terminal rod part ATRP, the terminal rod TR has a diameter DIA. The additional terminal rod part ATRP and the terminal rod may be connected e.g. via a bolt BOL and nut (not illustrated) connection through a terminal hole TH in the terminal rod TR and in the additional terminal rod part ATRP. Once connected the diameter DIA may be increased as described below. The terminal holes may be larger than the diameter of the bolt to allow the additional terminal rod part to move (slide on the terminal rod) while the bolt is being tightened. It is noted that the sides of the terminal rod and additional terminal rod part have matching divergent surfaces. Further, the contact area CA i.e. the side of the terminal rod also has a divergent surface which matches a divergent inner perimeter surface of the conductor PT.

[0134] Fig. 3b illustrates the side of the interface module facing and configured for being in physical contact with the electrical component. It can be seen that as the contact area of the terminal rod, this side of the interface module is provided with a divergent surface for optimizing the electrical connection between the interface module and the electric component.

[0135] Further, fig. 3b illustrates that the terminal rod is hollow which is advantageous in that in this way, the bolt head can be in the hollow terminal rod once that is connected to the conductor. Thereby, it is no hindrance for connecting the interface module to an electric component.

[0136] Fig. 3c illustrates the interface module of fig. 3a in further details. It can be seen that the side of the interface module facing the bolt is defined as the electric component plane ECP. Further, a center axis CAX of the terminal rod is illustratedwhich is perpendicular to the electric component plane ECP i.e. angle AX is 90 degrees.

[0137] Also, it is noted that the terminal rod and the additional terminal rod part both have slope parts SP. Once the bolt / nut is tightened the slope parts SP will expand the total diameter DIA of the terminal rod and thus create a force against the inner perimeter of the conductor PT. By this force, the interface module is connected to the conductor PT without the need of threaded parts inside the conductor.

[0138] The slope part of the terminal rod is illustrated with divergent surface for optimizing the electric connection to the additional terminal rod part. Hence, the additional terminal rod part has a matching divergent surface. The divergent surfaces are also used to control the sliding of the two slope parts in a controlled manner.

[0139] The interface module of fig. 3c illustrates an elevated conductor interface plane ECIP. As the interface module is connected to the conductor inside the conductor the end of the conductor can be placed against the elevated conductor interface part. It should be noted that the terminal rod may extend directly from the interface module base which in that case would coincide with a conductor interface plane.

[0140] If desired, the divergent portion of the terminal rod may be designed to prevent contact between the end of the conductor and the elevated conductor interface plane. Further, the divergent portion may also be designed provide a predetermined angle between the interface module and the conductor.

[0141] The elevated conductor interface plane may be used to position the conductor correctly before and during tightening the interface module to the conductor. If this is desired, then the elevated conductor interface plane may fit inside the conductor i.e. having a diameter that is adapted to the inner diameter.

[0142] The length L of the terminal rod TR is measured as the distance from where the terminal rod starts at the interface module base and to its end as illustrated. It should however be noted that the additional terminal rod part may extend this length L if needed. The length of the two terminal rod parts together may be more than 3cm toensure sufficient mechanical and electrical connection between interface module and conductor. Also, with respect to the electric and at least the mechanic connection, the length of the two terminal rod parts is relevant. Hence, the longer the better mechanic stability. With respect to the electric connection, the area of contact (i.e. in this embodiment the divergent surfaces) should be sufficiently large to allow an area to be deformable by the force component from the bolt. Examples of sufficient total length of the the two terminal rods are between 2cm and 15cm, such as between 3cm and 10cm i.e. 4, 5, 6, 7, 8 or 9cm.

[0143] The conductor illustrated in fig. 3d comprises outer and inner perimeters OP, IP and it is noted that the inner perimeter IP is equipped with a divergent surface matching the divergent surface of the contact area of the terminal rod and additional terminal rod.

[0144] Further, it is noted that the conductor PT comprises a plurality of grooves G contrary to the conductor of fig. 2d that only comprises one groove G. More grooves facilitate sharing of current through the conductor in more branches and thus ensure better usage of current conducting material of the conductor. This is at least truth in AC systems where proximity effects occur.

[0145] It should be noted, that when a terminal rod is provided inside a conductor, the terminal rod may be the primary current conducting element of the interface module. The part of the interface module that is only in contact with the end of the conductor such as e.g. an elevated conductor interface plane may also conductor current but may be considered a secondary current conducting element. Hence, a primary current conducting connection element may have a diameter that is less (e.g. dynamic) than the inner diameter of the conductor and the secondary current conducting connection element may have a diameter equal to or larger than the outer diameter of the conductor.

[0146] The interface module IM illustrated in fig. 4a is somewhat similar to the interface module illustrated in fig. 2a-2c. Here at fig. 4a, the terminal rod of theinterface module is simply not circular. This is because the conductor to which it is to be connected is not circular exemplified in fig. 4b.

[0147] The terminal rod TR comprises a contact area at its end. The contact areas has a first contact area distance 1 CADIS measured between a first and a second contact area point 1CP, 2CP. To reduce material consumption, it is preferred that this distance 1 CADIS is equal to or less that an outer conductor distance OCDIS of the conductor PT. As illustrated in fig. 4b, the outer conductor distance OCDIS is measured between a first and a second conductor point 1COP, 2COP

[0148] The functionality and connectivity of the interface modules of fig. 2a and 4a are the same and will therefore not be repeated.

[0149] The interface module IM illustrated in fig. 5a is somewhat similar to the interface module illustrated in fig. 3a-3c. Here at fig. 5a, the terminal rod is joined by the terminal rod TR and an additional terminal rod part ATRP and is not circular. This is because the conductor to which it is to be connected is not circular exemplified in fig. 5b. A rectangular shaped conductor may be preferred over a circular e.g. is heat dissipation is of high importance in that the surface area for distribution of heat is larger.

[0150] The second contact area distance 2CADIS measured between the third and fourth contact points 3CP, 4CP is adjustable by connection of the terminal rod and additional terminal rod part ATRP. To be able to insert the joint terminal rod inside the conductor, the second contact area distance 2CADIS should be less than the inner conductor distance ICDIS which is measured between third and fourth conductor points COP3, COP4 as illustrated in fig. 5b. It should be noted that conductor points can also be defined on the outer perimeter of the circular conductors even though not illustrated.

[0151] The functionality and connectivity of the interface modules of fig. 3 a and 5 a are the same and will therefore not be repeated.

[0152] To facilitate optimal electric connection, the parts configured for engaging with each other i.e. parts of the interface module and conductor, may be provided with divergent portions / surfaces. Divergent portions should be understood as a non-planar structure or surface. The divergent portion of two interfacing parts should preferably match when connected. Matching divergent portions may e.g. be a sawtooth pattern with truncated tips just to mention one. In some embodiments, the sawtooth pattern may have a pitch in the range of 0.5mm to 5mm, such as 1mm to 3mm. The angle of the sawtooth teeth relative to the surface plane may be in the range of 30 to 60 degrees, for example approximately 45 degrees. The tips of the sawtooth pattern may be truncated by a distance of 0.1mm to 1mm, which may improve contact area and reduce stress concentrations. Alternative divergent surface profiles may be used, such as sinusoidal profiles, trapezoidal profiles, knurled patterns, or combinations thereof. In some cases, the divergent surface may comprise a series of concentric ridges or grooves, which may be particularly suitable for circular contact areas. The specific geometric parameters of the divergent surfaces may be selected based on application requirements such as the desired clamping force, required contact area, material properties of the interface module and conductor, and manufacturing considerations. When both interfacing parts are equipped with matching divergent portions, the clamping force provided when tightening the two plans of the two parts together is impacting one another via the plans of the sawtooth in a direction that is not parallel to the clamping force. In this way an improved electric connection therebetween is established due to the engagement between these divergent portions. The clamping force may be applied by tightening a bolt with a nut in the terminal holes TH.

[0153] An electric component may be connected to a conductor via the interface module via different terminal design. The interface module design may be designed to be able to engage with the terminal design of the electric component. An example of a design that match and enable engagement is if the electric component holes ECH match holes in a terminal of the component. Further, if the interface module comprises a divergent portion, the component terminal should comprise matching divergent portions.

[0154] Terminals of a component to which the conductor is connected via the interface module may comprise holes through which bolts can pass and in this way, via threaded parts of the holes in the component terminal, connect the component terminals and the interface module.

[0155] Another type of component terminal and connection between interface module and electric component is illustrate in fig. 6a and 6b.

[0156] The interface module IM illustrated in fig. 6a could be similar to the one illustrated in previous figures. The illustrated interface module may provides a planer surface (or with divergent portions on its surface) that is adapted to interface a corresponding terminal on the electric component EC at an electric component plane ECP. In fig. 6a, the terminal of the electric component EC and of the interface module IM is connected via bolts in the electric conductor holes ECH. Thereby a current path is created from the electric component via the interface module into and through the electric conductor PT. It should be noted that at this figure there is no distinction between electric component EC and terminal thereof. Further, it is noted, that it is not possible to see if any terminal rod is provided inside the conductor PT or the conductor PT is simply connected to the interface module at the conductor interface plane CIP.

[0157] The interface module IM illustrated in fig. 6b could be similar to the one illustrated in fig. 6a. The electric component EC in fig. 6b may be a busbar or a transition piece between the conductors PT and a busbar. The terminals of the busbar may be implemented as terminal holes TH in the busbars. These holes TH are adapted to receive a bolt that is also going through holes in a terminal adaptor TA.

[0158] The busbar has a terminal plane also referred to as electric component plan ECP in the XY plane. The interface module IM has a terminal plan also referred to as the conductor interface plan CIP in the YZ plane. For the two terminal plans to meet, the terminal adapter TA is introduced therebetween. This terminal adapter TA is at one side designed so that terminal holes TH thereof are aligned with holes in the busbar and at another side designed so that terminal holes thereof are aligned with holes in the interface module. In this way the same interface module can be used in both endsof the conductor PT to connect the conductor to electric components EC having terminal planes.

[0159] Fig. 6b illustrates two conductors PT connected to the same electric conductor (here busbar). To allow this, a terminal adapter TA is used to facilitate the connection of two (or more) conductors PT to one electric component. As indicated, the upper conductor PT is connected directly to the terminal adapter TA i.e. without the use of an interface module. Hence, a terminal rod similar to the one described above of an interface module may be provided on the terminal adapter. The lower conductor may be connected to the terminal adapter with an interface module as described above.

[0160] Figures 6c-6f illustrates various types of conductors PT with interface modules IM. Fig. 6c illustrates two linear conductors PT connected via interface modules IM thereby forming a longer conductor. Fig. 6c illustrates how two linear conductors can be connected to extend the length of a conductor.

[0161] Fig. 6d illustrates a conductor PT comprising two conductors PT and three interface modules IM. It is noted that the two conductors have a different slope of the helix. This may be due to the difference in length and a requirement that the helix should have two turns. The interface modules may be used to connect the conductor PT to electric components. The leftmost interface module may be used to connect the modular conductor to a circuit breaker. The middle and right most interface module may be used to connect to two parallel conductors / busbars carrying the same phase current. Parallel conductors may be used either because the current is too large to be carried by on conductor or because the current should be conducted to different locations in an electric system. The interface modules may be similar to the above described.

[0162] Fig. 6e illustrates a conductor PT comprising two parallel conductors connected with an interface module IM.

[0163] Fig. 6f illustrated a conductor assembly (also referred to as a current distribution assembly) similar to the conductor assembly illustrated in fig. 6d. the difference to the assembly illustrated in fig. 6d is that the conductors PT are welded Wto the interface modules IM. Further, the conductors PT do not have any groves i.e. they are tubular conductors without groves.

[0164] It should be noted that the illustrated way of connecting conductors to electric components i.e. the design of the illustrated terminals of the electric components, terminal adapter and of the interface module is only examples for explanation. Hence, the terminals can be designed in various other ways such as with bolt part protruding from the terminal the electric components, interface modules such as cable shoe , etc. The interface module design is adapted to the design of the terminals of the electric component . In some cases, terminal adapters may be needed e.g. to be able to establish a connection or to be able to use standard terminal either of the conductor or at the electric component.

[0165] The termination of a conductor may in a simple form include holes, e.g. with a threaded part. A conductor with such threaded parts can via bolts be used to mount the conductor to an interface module. One example for explanation only could be that the electrical component to which the conductor is to be connected, comprises a terminal designed so that the interface module is allowed to be surrounded by the terminal or to surround the terminal of the electric components. In this way, a bolt through the terminal and into the conductor / interface module or vice versa can be used to mount the conductor / interface module to the electric component. As indicated, the conductor may be a tubular or massive conductor.

[0166] In case the conductor is massive, cylindrical or square, a not illustrated interface module, is able to at least partly surround the conductor, can be used to establish a terminal of the conductor. Two or more of the parts that surrounds the massive conductor may comprise holes for bolts that via nuts is able to, when tightened, clamp the interface module to the conductor and thereby ensure that the conductor and the interface module are connected both mechanically and electrically.

[0167] The above examples are only to exemplify that various ways of connecting an interface module to a conductor or to a terminal of an electric conductor exists. Hence, other not specified examples may be used, such examples may include threadedparts of one of the busbars and the interface module allowing screwing the two together, insert and turn / click systems, etc.

[0168] Depending on the method of manufacturing the conductor, at least part of the interface module can be made monolithic with the conductor.

[0169] The interface module and electric conductor according to the invention may be implemented (as a system) in an electric current distribution system which should be understood as a high-power system that is configured for conducting one or more phase currents over 100A. Thus, a distribution system may simply be a current path between two sets of terminals with conductors therebetween i.e. systems that only conduct current from one terminal to another. It may be a system that is able to break or cut the current by means of circuit breakers or switchgear. It may be a system that shapes voltage / current such as in a power converter or transforms voltage from one voltage potential to another, etc. In fact, the function or type of system is not important. Conductors with or without grooves may be used in such systems. Conductors with grooves are advantages in systems used to conduct high AC currents where proximity effect impacts the currents way through the conductor.

[0170] If the conducting material of the conductors is isolated or if the conductors are located in a safe space such as in a fenced area, the conductors can be several meters long. In such situation the electric system could be a utility grid substation, power-to-x system or the like. Conductors of the system may be provided under ground level e.g. in ducts.

[0171] It should be mentioned that a conductor may comprise a contact surface which is an area of the surface of the outer perimeter of the conductor that is configured for connection of additional conductors. Hence, a contact surface could simply be a flat area against which e.g. an interface module of another conductor can be electrically connected.

[0172] The contact surface may be located between ends of a conductor and may in principle be similar to an interface module. As mentioned in relation to the interfacemodule, a contact surface may also be angled to branch off a conductor in a predetermined direction.

[0173] The tubular electric conductor PT (also sometimes simply referred to as power tube or conductor) as exemplified e.g. in fig. 2d and 3d that is connectable to the interface module of the present invention, comprises a first end IE, a second end 2E and a middle section MS provided between the first end and the second end. The middle section is illustrated in fig. 7 where four groves G are illustrated also referred to as electromagnetic fields control elements. It should be remembered that the electromagnetic fields control element can be implemented in ways alternative to grooves, the description of fig. 7 uses the term groove. The electric conductor PT is a three-dimensional conductor illustrated as a power tube. The middle section extend between the two conductor ends. The grooves can extend all the way between the two conductor ends or the grooves can start and stop anywhere along the middle section. In this way the middle section may comprise one or more groove sections between the two conductor ends.

[0174] An electric conductor PT with one or more grooves G is advantageous in that it has the effect, that the current through such conductor is divided into each of the plurality of branches B formed by these grooves. Hence, by design of these grooves it is possible to design / control how the current is conducted / guided through the part of the middle segment having grooves. Controlling where in the conductor the current is actually conducted can be done this way due to the electromagnetic phenomenon referred to as skin effect, that causes current to seek towards the perimeter of the conductor. Thus, when first the current has entered a branch, the current will stay in this branch. Accordingly, to gain full control of the current, the grooves should go all the way through the current conducting material as illustrated in fig. 7.

[0175] Effect may be achieved by providing grooves that do not go all the way through the current conducting material as illustrated in fig. 7.

[0176] By this opportunity to design grooves and thereby control where in the conductor the current is actually conducted, it is possible to design a conductor withan equal distribution of current (also referred to as current density) across the cross-sectional area of the conductor. In this way, the amount of material of the conductor that is actually used for conducting current can be optimized. Such optimization may e.g. lead to a reduction of the cross-sectional area of the conductor and / or to choice of material that has a higher volumetric resistivity alternatively it allows to conduct higher current with the same current conducting cross-sectional area.

[0177] No matter type of conductor material, it is obviously preferred to utilize the conductor material best possible. It is known that current conducted through a cable / conductor is influenced by electromagnetic fields. This influence can be divided into impact from electromagnetic fields origin from the conductor (self-impedance) which in this document is referred to an internal impact and, impact from electromagnetic filed origin from a nearby conductor (mutual impedance) which in this document is referred to as an external impact.

[0178] The internal impact from the self-impedance results in a tendency of the current that is conducted, to be conducted towards the perimeter of the conductor. The electromagnetic phenomenon causing this tendency is referred to as skin effect. The extend to which this tendency is dominant i.e. how deep into the conductor, from the outer perimeter towards the center of the conductor, the current is conducted (referred to as skin depth), is depending on the resistivity of the conductor and the frequency of the current.

[0179] The skin depth is calculated by equation 1 :(. f~ Frequencye ™ x 10“

[0180] EQI: ’

[0181] The skin effect is a fact in AC systems and is undesired in that it may cause heating in the conductor and uneven current density across the cross-sectional area of the conductor, leading to conductor material not being used for conducting current.

[0182] The external impact from the mutual impedance occurs to a first conductor when that conductor is located next to a second conductor or other current conducting elements that is conducting a current (AC).

[0183] If both of the first and second conductors are conducting an AC current, the external impact results in a tendency of the current that is conducted in the second conductor, to be pushed away from the first conductor or dragged towards the first conductor and vice versa. Whether the current is pushed or dragged depends on the direction of the current in the first and or in the second conductor. The electromagnetic phenomenon causing this tendency is referred to as proximity effect. The extend to which this tendency is dominant i.e. how much the current is pushed or dragged is depending on the distance between the first and second conductors and the size of the current. The higher current and the closer distance the stronger proximity effect.

[0184] Summing up, when conducting an AC current in a conductor, the current will have a tendency to seek to the perimeter of the conductor leading to increased losses and unused material in the center of the conductor. Further, if the same conductor is located next to another current conducting element such as a conductor, the current in that conductor will have a tendency to displace the current towards one of the sides of the conductor.

[0185] To mitigate and / or control the impact of these electromagnetic fields coupling effects, one or more grooves are provided in the conductors modules. As mentioned, a groove may be provided into the perimeter of the conductor module, may be added to the outer perimeter as a protrusion. If the conductor has a hollow center part, the grooves or protrusions may be provided into / onto the inner perimeter or in combination with grooves provided into / onto the outer perimeter. The preferred implementation to date is as a groove.

[0186] A cross-sectional area of two neighboring prior art conductors conducting a current would be influenced by both the skin effect and the proximity effect. The current would be concentrated at the perimeter of the conductor and in one exampletowards the side of the nearby conductor. The current could also run in the side away from the nearby conductor depending on direction of current.

[0187] When the current conducted by the conductor as the one illustrated in fig. 7, is not influenced by the proximity effect, when the self-impedance (i.e. self-resi stance + self-inductance) and resistivity in the branches B is the same, an equal share of the total current Itot is conductor in the 4 branches. Assuming that all of the current was conductor in the branches (i.e. the conductor only comprises branches that are not electrically connected between the ends and go all the way through), each branch would conduct Itot / 4 current.

[0188] If a conductor was positioned nearby, the current would displace in the cross-sectional view, as described above due to the proximity effect. To avoid this, the conductors comprise grooves G. The grooves G spin around the perimeter of the conductor as illustrated in fig. 7 forming a helix groove, also referred to as a spiral or helix in this document, encircling the perimeter of the conductor. Optimally, with respect to proximity effect, each branch B would encircle the perimeter of the conductor once i.e., a 360 degrees encircling, twice i.e. 720 degrees encircling, etc.

[0189] It should be noted that one turn of the groove is sufficient to sufficiently eliminate the consequence of the proximity effect. In some designs of the conductor, one continuous groove of one turn is not possible and thus one or more than one turn may be provided by one or more groove parts. However, it should be noted that the longer groove, the longer current path and thus higher resistance to the current through the conductor. Accordingly, the number of turns of the helix should not be increased without considering this aspect.

[0190] The skin effect causes most of the current to be conducted in the branches (even in branches of a massive conductor). When the branches are turning in a helix around the perimeter of the conductor, the current in the branches on the opposite side of the conductor, with respect to the nearby conductor causing the proximity effect, cannot “flow out of the branch” and the proximity effect is thus eliminated. The reason why the helix around the perimeter works is because in this way all branchesexperience the same average fields from nearby conductor(s). Hence, induced voltages in all branches equal out, thereby eliminating the possibility of electromagnetic fields driving eddy currents in the branches.

[0191] In this way, contrary to the example of the prior art conductors, the material of the conductor on the opposite side of the nearby conductor, is also used for conducting current. Thereby, a conductor is provided, which when used in a current distribution system with more than one conductor, is optimized with respect to usage of conductor material.

[0192] The effect of the helix grooves i.e. the optimized material usage may have the effect that the cross-sectional area of the conductor can be reduced. Hence, compared to copper conductors without helix grooves, the current conducting cross-sectional area of a copper conductor with spiral grooves can be reduce with more than 50%. Simulations has shown that in large systems where five to six 10mm x 100mm copper conductors are used to conduct a phase current, a reduction of up to 70% of the copper material can be saved. If the frequency is higher e.g. in electric systems comprising reactors, semiconductor switches such as IGBT, the frequency is higher and thus the savings on material can be higher. In such systems the phase current conducted may be 1000 A to 6000 A.

[0193] As mentioned, the conductor illustrated in the figures of this document are tubular conductor i.e. a conductor where the center part is removed and thus the cross-sectional area is defined between an outer perimeter OP and an inner perimeter IP. As indicated, the grooves can be implemented in massive conductors or in other not mentioned types of conductors having the effect describe in this document.

[0194] The interior space defined by the inner perimeter of a tubular conductor can be used for guiding of a cooling fluid. Hence, if a flow of air is directed through the interior space, heat from the conductor can be removed.

[0195] The grooves are formed as continuous slope grooves or as stepwise grooves in the outer or inner perimeter of the conductor. The implementation of the groove is not important from an electric perspective. Most important is that the groove isprovided and both with respect to production and current conduction a groove with a continuous increasing / decreasing slope with not too many changes of directions is preferred. Continuous here should be understood as opposite to stepwise. Continuous grooves should be understood as the slope of the groove is continuous increasing or decreasing or the slope may be constant

[0196] The grooves may be defined by length and depth to have a predetermined resistance to electric current. The depth may be defined by the skin depth of the current or it may go all the way through the current conducting material. If the grooves go all the way through, they may be short at to increase stability and provide predetermined locations of connection. These predetermined locations may be found by simulation or calculations as where the current in a branch has 0 voltage crossing to avoid current to run from one branch to the other of the short branches.

[0197] The width of the groove may be as thin as possible to make, and in many applications a width of 1 millimeter or 2 millimeters may be sufficient. In some embodiments, the groove width may be selected based on the skin depth of the current in the conductor material; for example, the groove width may be less than or approximately equal to the skin depth to minimize material removal while still achieving effective current separation between branches. In some cases, the groove width may be in the range of 0.5% to 5% of the outer diameter of the conductor, such as 1% to 3% of the outer diameter. For higher current applications, wider grooves may be used to provide improved thermal dissipation and to accommodate manufacturing tolerances. In some embodiments, groove widths in the range of 0.5mm to 5mm may be used, with narrower grooves being suitable for smaller conductors and wider grooves being suitable for larger conductors or higher current capacities. The selection of groove width may also depend on manufacturing considerations, such as the capabilities of the extrusion, cutting or milling equipment used to form the grooves, and on mechanical considerations such as the structural integrity of the conductor branches.

[0198] Further, it should be noted that the more turns of a helix groove, the longer current path and thus higher resistance to the current through the conductor.Accordingly, the number of turns of the helix should not be increased without considering this aspect.

[0199] According to the above, the invention relates to an interface module IM for connection between an electric conductor PT and an electric component EC. Such interface module may be used in high power / high current systems where currents above 100A, such as above 500A, such as above 1000A are used. Examples of such systems include electric systems such as power converter, reactors, switchgear, power distribution systems, etc. Also power supply to e.g. electrolysis stacks that need high power to produce hydrogen may be supplied at least partly from a modular conductor of to the present invention. At least an AC part of such power supply would benefit from a conductor of the present invention.

[0200] The interface module may be used for terminating individual branches or groups of conductors or individual conductors in groups of two or more conductors. Allowing such branches / conductors to be connected to an electric component.

[0201] Different methods of manufacturing an interface module for a conductor with grooves according to the present invention exists. The conductor may be manufactured by extrusion, alternative by laser or waterjet cutting and yet another alternative would be milling. Grooves may be applied to a tube or to a sheet material, which is then formed into a tube by e.g. rolling and / or welding. Additive manufacturing is of course a possibility however, it is not the preferred due to the length of the conductor.ListIM. Interface ModulePT. Conductor, Power TubeCA. Contact AreaCIP. Conductor Interface PlaneECP. Electric Component PlaneDIA. Diameter of contact areaTH. Terminal HolesECH. Electric Component HoleEC A. Elevated Contact AreaTR. Terminal RodATRP Additional Terminal Rod Part OP. Outer PerimeterOD. Outer DiameterIP. Inner PerimeterID. Inner DiameterTP. Threaded PartG. GroovesSP. Slope PartCAX. Center AxisTA. Terminal AdaptorEC. Electric ComponentIMB. Interface Module BaseBOL. BoltW. Welding1CP-4CP Conductor PointsCOP1-COP4 Conductor Points1 CADIS, 2CADIS DistancesOCDIS Outer Conductor Distance ECIP Elevated Conductor Interface Plane CL A Longitudinal axis of conductor CDA Current distribution assembly

Claims

Claims1. A current distribution assembly (CD A) comprising:an interface module (IM); andan electric conductor (PT), extending along a longitudinal axis (CLA), connected to the interface module (IM),wherein the interface module (IM) comprises an interface module base (IMB), the interface module base (IMB) comprising a contact area (CA), the contact area (CA) establishing an electric connection between the interface module (IM) and the electric conductor (PT), andwherein the electric connection is part of an electric current path from the interface module (IM) into a current conducting material of the electric conductor (PT).

2. A current distribution assembly according to claim 1, wherein the contact area (CA) defines a conductor interface plane (CIP) and wherein the longitudinal axis (CLA) of the electric conductor (PT) is perpendicular to the conductor interface plane (CIP) when the interface module (IM) is electrically connected to the electric conductor (PT).

3. A current distribution assembly according to any one of claims 1 or 2, wherein the current path in the electric conductor (PT) comprises one or more branches (B) defined by one or more grooves (G), and wherein the one or more grooves (G) are provided into the current conducting material of the electric conductor (PT).

4. A current distribution assembly according to any of the preceding claims, wherein the contact area (CA) of the interface module has a diameter (DIA) that is less than or equal to an outer diameter of the electric conductor (PT).

5. A current distribution assembly according to any of the preceding claims, wherein the interface module is mounted to the electric conductor (PT) by bolts and nuts or by welding’s.

6. A current distribution assembly according to any of claims 1 to 4, wherein the interface module (IM) and the electric conductor (PT) are monolithic.

7. A current distribution assembly according to any of the preceding claims, wherein the contact area (CA) of the interface module (IM) has a first contact area distance (1CADIS) between a first contact area point (1CP) and a second contact area point (2CP), that is less than or equal to an outer conductor distance (OCDIS) measured between a first conductor point (1COP) and a second conductor point (2COP) of the electric conductor (PT).

8. A current distribution assembly according to any of the preceding claims, wherein the contact area (CA) of the interface module (IM) has a second contact area distance (2CADIS) measured between a third contact area point (3CP) and a fourth contact area point (4CP), that is less than an inner conductor distance (ICDIS) measured between a third conductor point (COP3) and a fourth conductor point (COP4).

9. A current distribution assembly according to any of the preceding claims, wherein the electric conductor (PT) comprises inner fastening means.

10. A current distribution assembly according to claim 9, wherein the inner fastening means are threaded parts (TP) configured for receiving bolts (BOL).

11. A current distribution assembly according to any of the preceding claims, wherein the electric conductor (PT) is a tubular electric conductor, and wherein the current conducting material is provided between an inner perimeter (IP) and an outer perimeter (OP) of the tubular electric conductor (PT).

12. A current distribution assembly according to claim 11, wherein the tubular electric conductor (PT) is a hollow elongated cylinder.

13. A current distribution assembly according to any of claims 11 or 12, wherein the contact area (CA) of the interface module (IM) has a diameter (DIA) that is less than the inner diameter (ID) of the tubular electric conductor (PT).

14. A current distribution assembly according to any of the preceding claims, wherein the contact area (CA) of the interface module (IM) comprises a terminal rod (TR)extending from the interface module base (IMB), wherein the interface module base (IMB) defines an electric component plane (ECP).

15. A current distribution assembly according to claim 14, wherein an angle (Ax) is defined between a longitudinal center axis (CAX) of the terminal rod (TR) and the electric component plane (ECP).

16. A current distribution assembly according to any of claims 14 or 15, wherein the terminal rod (TR) has a length (L), measured from the interface module base (IMB), of at least 3 cm.

17. A current distribution assembly according to any of claims 14 to 16, wherein the terminal rod (TR) comprises an additional terminal rod part (ATRP), wherein the additional terminal rod part (ATRP) is movable relative to the terminal rod (TR).

18. A current distribution assembly according to claim 17, wherein the terminal rod (TR) and the additional terminal rod part (ATRP) has slope parts (SP).

19. A current distribution assembly according to claim 18, wherein the slope part (SP) and / or the outer perimeter of the terminal rod (TR) and / or of the additional terminal rod part (ATRP) has a divergent surface matching a divergent surface of the inner perimeter of the tubular electric conductor.

20. A current distribution assembly according to any of claims 14 to 19, wherein the contact area (CA) further comprises an elevated conductor interface plane (ECIP).

21. A current distribution assembly according to any of claims 14 to 20, wherein the terminal rod (TR) is hollow.

22. A current distribution assembly according to any of claims 14 to 21, wherein the contact area (CA) defines a conductor interface plane (CIP) at the end of the terminal rod (TR).

23. A current distribution assembly according to claim 22, wherein an angle (A) is defined between the conductor interface plane (CIP) and the electric component plane (ECP), wherein the angle (A) is between 0 and 90 degrees.

24. A current distribution assembly according to any of claims 14 to 23, wherein a contour of the contact area (CA) at the end of the terminal rod (TR) is defined by outer perimeter (OP) of the current conducting material of the electric conductor (PT).

25. A current distribution assembly according to any of the preceding claims, wherein one or more terminal holes (TH) are provided in the contact area (CA) and are aligned with one or more threaded parts (TP) of the electric conductor (PT), wherein the contact area (CA) and the electric conductor (PT) are configured for being connected via one or more bolts (BOL) through the terminal holes (TH) into the threaded part (TP).

26. A current distribution assembly according to any of claims 14 to 25, wherein at least part of the cross-sectional area of the electric conductor and at least part of the contact area (CA) at the end of the terminal rod (TR) comprises a divergent surface.

27. A current distribution assembly according to any of the preceding claims, wherein the interface module (IM) is a terminal interface module.

28. A current distribution assembly according to any of the preceding claims, wherein the interface module (IM) is a conductor connection interface module.

29. A current distribution assembly according to any of the preceding claims, wherein the interface module (IM) is a conductor split interface module.

30. A current distribution assembly according to any of the preceding claims, wherein the interface module (IM) comprises a poka yoke element.

31. A current distribution assembly according to any of claims 3 to 30, wherein the one or more grooves (G) are helix grooves in the inner perimeter (IP) or in the outer perimeter (OP) of the electric conductor (PT).

32. A current distribution assembly according to any of the preceding claims, wherein the electric conductor (PT) comprises one or more helix protrusions on its inner perimeter (IP) or on its outer perimeter (OP).

33. A current distribution assembly according to any of the preceding claims, wherein the electric conductor (PT) is comprised by an electric cabinet.

34. A current distribution assembly according to any of the preceding claims, wherein the electric conductor (PT) has an outer perimeter (OP) of at least 4cm.

35. A current distribution assembly according to claim 31, wherein the one or more helix grooves (G) is implemented as air gaps.

36. A current distribution assembly according to any of claims 3 to 35, wherein the one or more grooves (G) separates the outer perimeter (OP) of the electric current conductor (PT) into a plurality of conductor branches (B).

37. An electric system comprising an interface module (IM) connected to an electric conductor (PT), the interface module (IM) comprises an interface module base (IMB), the interface module base (IMB) comprising a contact area (CA), the contact area (CA) being configured to establish an electric connection between the interface module (IM) and the electric conductor (PT),wherein the electric connection is part of an electric current path from the interface module (IM) into a current conducting material of the electric conductor (PT), andwherein the current path in the electric conductor (PT) comprises one or more branches (B) defined by one or more grooves (G) wherein the one or more grooves (G) is provided into the current conducting material.

38. A system according to claim 37, wherein the interface module and the electric conductor are defined by features of any one of the previous claims 1-36.

Images