CN110915107A

CN110915107A - Electrical machine having a conductor arrangement and an insulation for the conductor arrangement

Info

Publication number: CN110915107A
Application number: CN201780093761.8A
Authority: CN
Inventors: A.祖克斯; J.韦斯特伦德; J.曼特雷; S.察瓦拉斯; J.耶皮南; Z.科隆约夫斯基; P.坎尼南
Original assignee: ABB Schweiz AG
Current assignee: ABB Schweiz AG
Priority date: 2017-06-09
Filing date: 2017-06-09
Publication date: 2020-03-24
Also published as: WO2018224163A1; EP3635849A1

Abstract

An electrical machine (100) having a conductor arrangement (200) is proposed. The wound conductor arrangement comprises: an electrical conductor and an electrical insulation provided at least partially around the conductor. The electrical machine is adapted to apply a voltage up to the rated voltage Vmax to the conductor arrangement. The electrical insulation comprises a diamond containing insulating layer comprising diamond particles having a diameter of at least 1 μm in a direction substantially parallel to the conductor surface. The diamond containing insulating layer provides the highest dielectric strength and/or discharge resistance of the electrical insulation; and the diamond containing insulating layer has a thickness t in a range depending on Vmax_d。

Description

Electrical machine having a conductor arrangement and an insulation for the conductor arrangement

Technical Field

The present invention relates to the field of electric machines, and in particular to insulation for conductors of electric machines. The invention also relates to several insulating layers provided on and around the conductor.

Background

Electrical conductors for electrical machines, such as coils for electric motors or generators, are insulated for avoiding contact between the individual windings of the coils, but also for avoiding short circuits between the coils of the electrical machine and other electrically conductive components (e.g. the stator of the electric motor). For example, today main wall insulation (e.g. mica tape (tape) and impregnating resin) is used to insulate conductors at full potential from the stator core (core) at ground potential.

Currently, the so-called Vacuum Pressure Impregnation (VPI) technique is used and widely used by many machine manufacturers. In this process, a layer of mica tape is wound around the conductor. The layers of mica tape are impregnated with a thermosetting resin and subsequently heat cured to obtain a so-called main wall insulation — the final mica-resin composite. In the case of motors and small generators (< 15 kV), the complete stator with inserted mode-wound (form-wind) coils is fully impregnated throughout the VPI process. For large generators, insulated Roebel bars (Roebel bars) are manufactured and impregnated separately (single VPI).

The principle of using mica tape and resin impregnation has not changed for almost a century and is well established to produce main wall insulation over complex conductor shapes and overall dimensions, such as coils or Roebel bars for large electrical machines. The widespread use of robotics for coil shaping, insulating banding and consolidation (consolidation) has now improved the known processes in order to create finished stator coils and roebel bars. However, these insulation portions have poor heat conduction characteristics for the motor. In particular, mica tapes used in the windings of electrical machines are known to have good dielectric strength and partial discharge resistance, but poor thermal conductivity characteristics.

Since the losses in the form of heat that are generated are often a bottleneck in the design of the electrical machine, the low thermal conductivity of the insulation has a significant impact on the design constraints. For many materials suitable for electrical insulation, electrical insulators are also considered thermal insulators, assuming that thermal and electrical conductivity are closely related. This is due to the fact that: the free movement of electrons, which corresponds to electrical conductivity, is also considered to be a major factor in thermal conduction.

Disclosure of Invention

In view of the above, there is provided a motor according to claim 1 and the use of diamond particles according to claim 15 in an insulation layer of a motor. Further aspects, advantages and features of the present invention are apparent from the dependent claims, the description and the accompanying drawings.

According to an aspect of the invention, an electrical machine with a conductor arrangement is provided. The conductor arrangement comprises an electrical conductor and an electrical insulation provided at least partially around the conductor. The electrical machine is adapted to apply a voltage up to the rated voltage Vmax to the conductor arrangement. The electrical insulation comprises a diamond containing insulation layer comprising diamond particles having a diameter of at least 1 μm in a direction substantially parallel to the conductor surface. The diamond containing insulating layer provides the highest dielectric strength and/or discharge resistance of the electrical insulation. The diamond containing insulating layer has a thickness t according to the following formula_d

（1）

Wherein

In general, diamond can be both a good electrical insulator and a good thermal conductor. This effect is due to the fact that: diamond is capable of conducting heat (phonon) transfer) by lattice vibrations rather than by electrons. Thus, better thermal conductivity and higher dielectric strength than mica-based insulation can be provided by a conductor arrangement according to embodiments described herein. The use of diamond particles for the insulation of the conductor arrangement allows for a more compact motor design, higher voltages and thus higher efficiency and/or energy density. In addition, new thermal management methods for the electric machine are possible, thereby further enhancing performance.

The embodiments described herein allow for the utilization of extremely high thermal conductivity with thinner insulating layers than known insulating layers.

Drawings

The subject matter of the invention will be explained in more detail in the following text with reference to preferred exemplary embodiments which are illustrated in the attached drawings, in which:

fig. 1 is a schematic view of an electric machine having coils arranged as conductors;

fig. 2 and 3 show schematic front views of conductor arrangements according to embodiments described herein;

fig. 4 shows a schematic perspective view of a wound conductor arrangement according to embodiments described herein;

FIG. 5 is a schematic view of a conductor arrangement provided with an insulator according to embodiments described herein;

fig. 6 is a schematic partial and more detailed view of an electrical conductor arrangement provided with an insulator according to embodiments described herein;

fig. 7 to 10 show schematic views of a diamond containing insulating layer comprising a conductor arrangement according to embodiments described herein;

11 a-11 d show schematic top views on a belt according to embodiments described herein;

FIG. 12 shows a schematic view of a conductor arrangement with an insulator according to embodiments described herein;

FIG. 13 shows a schematic diagram of an electron discharge path according to embodiments described herein;

fig. 14 shows a schematic front view of a slot region with a conductor arrangement arranged in the slot region (slot region) according to embodiments described herein;

FIG. 15 shows a schematic cross-sectional view of a trough region according to embodiments described herein;

FIG. 16 shows a schematic front view of a trough area according to embodiments described herein; and

fig. 17 shows a flow diagram of a method of insulating a conductor according to embodiments described herein.

Detailed Description

According to embodiments described herein, there is provided an electrical machine comprising a conductor arrangement. For example, an electric machine according to embodiments described herein may be at least one of an electric motor, a generator, a transformer, and/or other electromagnetic devices such as an actuator and/or an electromagnet. Typically, the conductor arrangement may comprise a wound conductor, such as for example a coil of an electrical machine.

Fig. 1 shows an example of a wound coil arranged as a conductor in the basic structure of an electric motor. Electric motor 100 includes a stator 101 and a rotor 102. The stator 101 is exemplarily shown with a stator core 105, which stator core 105 is provided, for example, in a cylindrical shape, and which stator core 105 is provided with six wound conductors 106 or a plurality of turns, such as coils or windings, which are connected to a power source. The magnetic rotor 102 is adapted to rotate about an axis 104 directed in the plane of the drawing sheet. By providing a current in the winding 106, a magnetic field is induced. The magnetic rotor 102 rotates. The rotor 102 continuously rotates because the magnetic forces between the rotor 102 and each winding 106 repel and attract each other. In this way, rotational movement of the rotor 102 is achieved. It will be appreciated by those skilled in the art that the electrical machine as referred to herein is not limited to the design shown in fig. 1.

FIGS. 2, 3 and 4 show a guideA simplified example of an electrical conductor 201 of the bulk arrangement 200. The simplified drawing shows a conductor 201 having a rectangular cross section. The electrical conductor 201 is (at least partially) surrounded by an electrical insulation 203. The electrically insulating part comprises a total thickness t_tot。

Total thickness t of the electrically insulating part_totIs described according to the following equation (2):

（2）

wherein

。

The electrical insulation 203 comprises a diamond containing insulating layer 330. The diamond containing insulating layer 330 has a thickness t_d. Thickness t of diamond-containing insulating layer_dDescribed by the following equation (1):

（1）

wherein

。

Due to the excellent dielectric strength of the diamond layer, so that for t_dLower limit of thickness (where k is_d= 0.0005) is possible, allowing even very thin layers to still withstand a given dielectric voltage. Such a thin layer is preferably suitable for a rated voltage V of at least 0.1kV, preferably at least 1kV_max. For k_dIs 0.001, a more preferred lower limit is 0.005, and a particularly preferred lower limit is 0.015. A lower limit of 0.001 is particularly relevant in the case of applications where the diamond-containing layer is directly immersed, and a lower limit of 0.005 is particularly relevant in the case of applications where the diamond-containing layer is carried.

On the other hand, due to the excellent thermal conductivity of the diamond layer, even the upper thickness limit (where k is_d= 0.0555) still allowing for a reasonable thickness while allowing for excellent dielectric strength and still good cooling characteristics. For k_dIs 0.03, and for k_dA particularly preferred lower limit of (b) is 0.02.

Small thickness t of diamond containing insulating layer_dAnd the excellent insulating and thermally conductive properties of diamond also allow for a small overall thickness t of the electrically insulating portion_totAs described by equation (2) above.

The periphery of the electrical conductor 201 is surrounded by the electrical insulation 203, while the front side of the conductor is not covered by the electrical insulation 203. Fig. 2 shows a cross-section in the x-y-plane of the conductor shown in the perspective view in fig. 4. Fig. 3 shows that the electrically insulating part 203 of the electrical conductor 201 comprises two insulating

layers

330 and 202. Insulating layer 330 is a diamond containing insulating layer. The two insulating

layers

330 and 202 have different insulating properties, such as different conductivity values. The diamond containing insulating layer 330 provides the highest dielectric strength and/or discharge resistance. The electrical conductor has a longitudinal axis or z-direction. The insulating

layers

203, 202 are arranged in the longitudinal direction of the electrical conductor 201.

Fig. 5 shows a conductor arrangement 200 comprising an insulation in the form of a strip 210, said strip 210 having a diamond containing insulating layer for electrically insulating the conductor. The example of fig. 5 shows a longitudinal conductor, a portion of which is drawn. The tape is wound around the conductor in a spiral manner in the winding direction W. The winding direction W substantially corresponds to the longitudinal z-direction of the conductor arrangement 200. Fig. 6 shows an enlarged portion of the conductor arrangement of fig. 5. Fig. 6 shows insulation in the form of tape 210 having overlapping

portions

214, 215 and 216, where the tape 210 used to form the insulation overlaps the previously wound tape portion.

The tape 210 in the example of fig. 5 and 6 includes a diamond containing insulating layer that helps to escape heat through the insulating layer and to help insulate the electrical conductors.

Fig. 7 shows a more detailed view of the structure of the electrically insulating part 203, said electrically insulating part 203 comprising a carrier 310 comprising a diamond containing insulating layer 330 and a tape. Thickness t_dThe height of the diamond-containing insulating layer 330 perpendicular to the conductor surface is depicted, while the thickness 302 is the height of the entire strip. In the example of a ribbon, the ribbon thickness 302 is similar to the total insulation thickness t of the electrical insulation 203_tot. Insulation containing diamondThe layer comprises diamond particles 320 provided as platelets 334 arranged on the carrier 310. The carrier 310 is a mesh or membrane. The carrier 310 can also comprise a carrier material such as a (non-woven) polyester mesh, a polyester film, a glass cloth, a non-woven glass cloth, a polyimide, or the like. Diamond plates (diamond plates) 334 are arranged in a continuous diamond plate layer parallel to the conductor surface in an at least partially staggered manner so as not to allow any direct straight discharge path through the diamond containing insulating layer.

Fig. 8 shows an example of a diamond containing insulating layer 330 provided by diamond powder 331. Although the example of fig. 8 is shown without carrier 320, the diamond-containing insulating layer 330 of fig. 8 may also be provided on carrier 320 (such as the carrier described above with respect to fig. 7), for example, for forming a tape.

Fig. 9 shows a further example for a diamond containing insulating layer 330, said diamond containing insulating layer 330 comprising diamond 333 provided in a carrier material 332. The diamond pieces 333 have different shapes and sizes.

Fig. 10 shows the diamond containing insulating layer 330 as an enclosed solid diamond surface 340. The enclosed solid diamond surface 340 is provided without a carrier and is applied directly onto an electrical conductor (not shown), for example by direct immersion.

Fig. 11a to 11d show schematic plan views on a belt 210 comprising a first region and a second region arranged as stripes. In the example of fig. 11a, two of the bars comprise mica and one bar comprises diamond particles. A diamond containing strip (diamond containing strip) 335 is arranged between two mica containing strips (mica containing strips) 350. The strips extend parallel to the longitudinal direction of the strip (z-direction). Fig. 11b and 11d show similar tapes with 3 or 5 of the mica-containing strips 350 and 2 or 4 diamond-containing strips 335, respectively. Fig. 11d shows another arrangement with a discontinuous diamond containing strip 335. The diamond containing strips 335 allow for both thermal conduction and electrical insulation.

Fig. 12 shows a schematic view of a conductor arrangement 200 comprising insulation in the form of a strip with an overlap region. The belt 210 comprises three strips of material as in fig. 11 a. In this example, the two mica-containing strips 350 overlap, while the diamond-containing strip 335 is a single layer. As in fig. 5, the winding direction W of the strip is in the longitudinal direction of the conductor arrangement (z-direction). A single layer of a diamond containing insulating layer provides excellent thermal conductivity for the entire insulating arrangement along and across the conductor (surface).

Fig. 13 shows a schematic of the electron discharge path through the diamond containing insulating layer 330, in which diamond particles 320, which may be provided as diamond platelets 334, are arranged in parallel. Although the diamond containing insulating layer 330 is thin, the discharge path is relatively longer than other robust insulating layers. Thus, the tape as shown in FIG. 7 contains desirable thermal conductivity and insulation properties.

Fig. 14 shows a schematic front view of a slot region 401 of a magnetic core of an electrical machine, wherein an electrical conductor 201 comprises an electrically insulating portion 203 arranged in the slot region 401. Insulation 203 separates conductor 201 from magnetic core 402. The insulating part 203 has a thickness t_tot. For example, the magnetic core 402 can be the stator core 105 of fig. 1, and the electrical conductor can be part of the coil 106 of fig. 1. However, the conductor can also be a conductor bar. The magnetic core 402 is ferromagnetic and electrically conductive. Thus, the insulation of the conductor 201 may be desirable to prevent any turn-to-turn failure. By providing a layer having a very low thickness t_totThe insulating portion 203 containing a diamond insulating layer of (a) can increase the amount of active conductor material, resulting in higher applicable voltage while ensuring excellent thermal conductivity and electrical insulation.

Fig. 15 shows a schematic top sectional view of a slot region 401 of a magnetic core of an electrical machine having a conductor arrangement 200 arranged therein. The slot region 401 includes a magnetic core 402 and a local heat spreader region 403. The conductor arrangement comprises a conductor 201 which is insulated with a tape 210 wound in the winding direction W. The winding direction W of the strip is in the longitudinal direction (z-direction) of the conductor. Tape 210 comprises a diamond containing insulating layer. The single winding 412 of the strip is arranged so as to allow direct heat flow towards the next local heat sink. Thus, the tape comprises a tape width 406, typically 20 mm to 35 mm, and a winding angle (winding angle) 407, typically 10 to 25 degrees, resulting therefrom. Heat escapes along the insulation, across the insulation and/or longitudinally with respect to the tape direction and/or with respect to the conductor surface through the diamond containing insulating layer of the tape.

Fig. 16 shows a schematic front sectional view of a conductor arrangement arranged in a slot region 401 of a magnetic core of an electrical machine, wherein the enhanced heat flow is indicated by black arrows. The conductor arrangement likewise has a conductor 201 and an insulation 203 comprising a diamond-containing insulating layer. Lateral side surfaces of the conductor arrangement are in contact with the magnetic core material, and bottom side surfaces of the conductor arrangement are in contact with slot wedges (slot edges) 405 at the open sides of the slots. In addition, a yoke air (yoke air) duct 408 is arranged in the yoke region 404 of the magnetic core and is in thermal contact with the top side surface of the conductor arrangement.

The magnetic core material, the slot wedge 405, and the yoke air duct 408 act as a heat sink, which allows the escape of heat away from the conductor 201. In this context, the slot wedge 405 and the yoke air duct 408 are the most efficient heat sinks. More generally, the conductor is thermally coupled to a plurality of heat sinks having different heat absorption rates.

The heat flow from the conductors to these heat sinks is shown by the thick arrows: as can be seen, heat not only flows across the insulating layer to the immediately adjacent core region, but most of the heat also flows along the insulating layer (parallel to the conductor surface) to the heat sink with the higher heat absorption rate, i.e., to the wedge 405 and yoke air duct 408.

Thus, heat escapes in a direction along the insulating layer and/or directly to the trench region 401. Heat escapes through the yoke air ducts 408 of the yoke region 404 and/or heat escapes through the magnetic core 402. The magnetic core 402 contains a heat sink (not shown) that allows the escape of heat away from the conductor 201. Heat escapes through the wedge region 405. Heat escapes in a direction along the insulation, across the insulation, and/or axially through the diamond containing insulating layer of the tape 210. New thermal management techniques and/or higher voltages can be used, which results in new machine performance levels. The heat flow in the machine can be designed more efficiently due to the changing conditions regarding the thermal properties of the diamond insulation.

Fig. 17 shows a flow chart 500 of an embodiment of a method. In step 501, an electrical conductor is provided, wherein the electrical conductor comprises a surface. Step 502 includes insulating the electrical conductor with one or more insulating layers and a diamond-containing insulating layer.

In general, it will be understood that embodiments of the invention are not limited to the embodiments shown in the drawings. Rather, the embodiments shown in the figures are examples only, such as examples of conductors. Further examples may include other conductor arrangements used in electrical machines for generating magnetic fields.

Definition of

In the following, definitions of general terms used throughout the literature are given.

It will be understood by a person skilled in the art that an electrical conductor as referred to herein may be understood as a conductor having any suitable shape, such as a cylinder on a substantially circular shape, a wound conductor comprising several windings, etc.

It will be appreciated by those skilled in the art that the conductive material as referred to herein may be electrically insulated in different ways. Thus, electrical insulation as referred to herein may be understood to include insulation of a single strand of conductor as well as insulation of the entire (wound) conductor (ground insulation). In addition, the terms "insulating" and/or "insulating layer" and the like as used herein refer to electrical insulation.

Mica is understood to be a silicate material, in particular a sheet silicate mineral. Mica can be described, for example, as a composite silicate with aluminum and an alkali metal. Some types of mica may contain iron, magnesium, lithium, fluorine, barium, manganese, and vanadium. It will be appreciated by those skilled in the art that mica is generally a material that can be used in different shapes and sizes, for example by splitting into flexible and transparent films. According to some embodiments, the mica may be a silicate material having a dielectric strength of about 110-120 MV/m (e.g., 118 MV/m). In addition, mica may be provided as flakes.

The term "substantially" as used herein means that there may be some deviation from the characteristic represented by "substantially". For example, the term "substantially parallel" refers to an arrangement of elements that may have some deviation from a perfectly parallel arrangement, such as a deviation from a parallel arrangement of up to about 15 °. The term "substantially no pores" (e.g., on a surface) as used below may include individual pores, which may be present, for example, due to manufacturing defects, etc.

The longitudinal direction of the electrical conductor may be understood as the axis of the electrical conductor extending in the direction of maximum extension of the electrical conductor. In the case where the wound conductor provides a coil such as having a ring shape or the like, the longitudinal direction may correspond to an axis extending in a circumferential (circumferential) direction of the wound conductor. In some embodiments, the y-direction may be a direction perpendicular to the longitudinal direction, such as the height of the electrical conductor. The x-direction may also be described as being perpendicular to the longitudinal direction, e.g. the width direction of the electrical conductor. If a wound conductor is referred to, both the x-direction and the y-direction can be described as the normal direction of the conductor surface. As used herein, the extension of the diamond particles in a direction substantially parallel to the conductor surface may be described as the extension of the diamond particles in any local plane and/or surface, such as an x-z plane or a y-z plane. The direction along the insulation may be understood as being parallel to the local plane defined by the insulation or the conductor surface. The direction across the insulation may be understood as being orthogonal to the local plane defined by the insulation or the conductor surface. The terms "axial" and "circumferential" may be understood to refer to a local spatial arrangement of conductor arrangements and are not understood to refer to a local spatial arrangement of an electrical machine.

Diamond particles may be understood as particles having a diameter of at least 1 μm. The diamond particles may be provided as diamond flakes and/or diamond powder. Embodiments described herein in terms of diamond sheets may be understood as embodiments that also function with other diamond particles (e.g., diamond powder). The diameter of the diamond particles may be understood as any diameter in a plane parallel to the (local) conductor surface.

A diamond-containing insulating layer comprising successively provided diamond particles may be understood as a layer in which: the diamond particles remain in contact with each other in this layer, in particular through the entire diamond containing insulating layer, for example through the entire thickness of the diamond containing insulating layer. Keeping in contact with each other does not necessarily mean that the diamond particles have to be in contact with other diamond particles over the whole surface, but a contact or even a point-like contact over a part of the surface may be sufficient. The diamond containing insulating layer as referred to herein may be provided in the form of a paper-like structure having one or more layers of successively provided diamond particles.

A discharge path as described herein may be understood as a path along an inter-grain region of the diamond-containing insulating layer that allows discharge.

The voltage Vmax as described herein may be understood as the rated (maximum) voltage of the motor. The motor is adapted to supply power to the conductor relative to a ground maximum voltage. Any suitable support voltage may be used without defining a maximum value.

Thickness t of diamond-containing insulating layer_dIs to be understood as any thickness, for example an average thickness substantially perpendicular to the surface of the conductor. Thus, the parameter k of the thickness_dCan be at k along the conductor surface_dMay be varied within the scope of the definition of (1).

Total thickness t of the electrically insulating part_totIs to be understood as any thickness, for example an average thickness substantially perpendicular to the surface of the conductor. Thus, the parameter k of the thickness_totCan be at k along the conductor surface_totMay be varied within the scope of the definition of (1). If a carrier is present, the carrier may be of total thickness t_totA part of (a).

General aspects and modifications

Next, the electrical machine and its conductor arrangement and individual aspects of its use are described in more detail. Wherein reference to the figures and their reference numerals are for illustration only. These aspects are not limited to any particular embodiment. Conversely, any aspect described herein can be combined with any other aspect(s) or embodiment described herein, unless otherwise specified.

According to embodiments described herein, an electrical machine comprising a conductor arrangement (typically a wound conductor arrangement) is described. The (wound) conductor arrangement comprises an electrical conductor having a longitudinal direction and comprising a conductor surface and an electrically conductive material, such as copper, iron, steel or the like. The conductor arrangement further comprises an insulation for insulating the electrical conductor, which electrical conductor comprises one or more insulation layers provided at least partially around the conductor. The one or more insulating layers typically comprise a diamond containing insulating layer comprising continuously provided diamond with diamond particles having a diameter of at least 1 μm in a direction substantially parallel to the (local) conductor surface. In addition, the diamond containing insulating layer provides the highest dielectric strength of the one or more insulating layers, and/or the diamond containing insulating layer provides the highest partial discharge resistance of the one or more layers.

Conductor/machine

The electrical conductor may be made of copper or the like. Typically, the conductive material of the conductor may include copper. According to some embodiments, the electrical conductor may have any suitable shape, such as a shape configured for application in an electrical machine. In some embodiments, the electrical conductor may be a wound conductor. The conductor may be a conductor coil or a conductor bar for a High Voltage (HV) rotating machine.

The conductor may be wound into a plurality of strands. The electrical insulation may be arranged for insulating the single strand (wound) conductor, so that the single wires of the coil may be understood as being isolated from each other. For example, the single strands or wires may be coated with an isolating material before being wound onto the wound conductor for the conductor arrangement. However, due to the application of the wound conductor in an electric machine, it may also be desirable to isolate the entire wound conductor from other (e.g., grounded) components of the electric machine, such as magnets, conductive materials, wires, and the like. In addition, the electrical insulation may be arranged for ground insulation of the conductor.

Embodiments described herein may also refer to an electrical machine, in particular an electrical motor, having a conductor arrangement according to any of the embodiments described herein. For example, an electrical machine as shown in fig. 1 may be equipped with a conductor arrangement according to embodiments described herein. For example, the wound conductor 106 or turns, such as a coil or winding, shown in fig. 1 may be at least partially surrounded by insulation including a diamond containing insulating layer according to embodiments described herein.

According to embodiments, the rotor 102 shown in fig. 1 may also include a wound conductor having electrical insulation as described herein. As an example, the coil may be arranged in the rotor. Generally, the electric machine as referred to herein may be an electric machine for high voltage. For example, the electric machine and the conductor arrangement according to embodiments described herein may be adapted for rated voltages between 0.1kV and 100 kV. The rated voltage Vmax is in particular greater than about 1 kV. More particularly, the voltage rating Vmax is greater than about 15 kV, and even more particularly, the voltage rating Vmax is greater than about 30 kV. In some embodiments, an electrical machine and a conductor arrangement according to embodiments described herein may be adapted to an electrical machine, such as a motor or a generator, for supplying an AC current to the conductor arrangement, the AC current having a frequency of about 5 to 1 kHz.

The electric machine is not limited to an electric motor but may also be at least one of a generator, a transformer and/or other electromagnetic devices such as an actuator and/or an electromagnet. Typically, the conductor arrangement may comprise a wound conductor, such as for example a coil of an electrical machine.

Insulating part

The insulating portions 203 of the embodiments described herein provide a corresponding topology to limit migration of electrons through the insulating portions, such as through a continuous surface topology. In particular, the topology of the insulation does not have a short path through the holes of the insulation, which makes it difficult to cross-discharge. The topology was chosen for the purpose of limiting electron migration and forcing electrons on a zig-zag path (which is set forth in fig. 13) in the insulating portion. The higher dielectric strength of the insulation according to embodiments described herein enables the use of thinner insulation. The combined effect of reduced insulation thickness and higher thermal conductivity of the insulation comprising the diamond containing insulation layer may further result in a positive effect on the enhancement of the thermal conductivity of the insulation system. In some embodiments (which will be described in detail below), a thinner carrier material for the insulating material may be used due to the lower mass of the diamond containing insulating layer. The electrically insulating part may comprise more than one insulating layer and/or carrier. Total thickness t of the electrically insulating part_totCan be described according to the following equation (2):

（2）

wherein

；

Wherein k is_totIs 0.07 and/or k_totA preferred upper limit of (b) is 0.09. Total thickness t_totMay not be constant over the entire conductor surface, but may be at k_totWithin the given range. The total insulation thickness may include all insulation layers and/or carriers. The support may have a lower limit of thickness of 0.01 mm.

According to some embodiments, diamond particles may be included in the insulation. In general, diamond has a higher dielectric strength and a much higher thermal conductivity than materials used for insulation purposes in electrical machines (e.g., mica). This allows the diamond based insulation to be much thinner and more thermally conductive than the mica based insulation. A thinner insulation with higher thermal conductivity results in better thermal management and more room for other active materials like copper and iron. In some embodiments, the thermal conductivity of the electrically insulating portion is between 0.2W/mK and up to 2200W/mK. The electrically insulating portion may comprise more than one insulating layer.

The embodiments described herein may be used for new motor designs that utilize higher efficiencies and/or energy densities. The described embodiments lead to economic improvements due to better thermal conductivity and possibly higher dielectric stress than, for example, mica-based insulation. Due to the better dielectric strength (and thus smaller insulation thickness) and better thermal conductivity, a new motor concept is achieved. The embodiments described herein allow for utilizing new freed space for more copper or iron and/or allow for utilizing new thermal management opportunities to create new high efficiency (cooler operation) and/or high energy density (thermally subject to greater current) electric machines.

With high thermal conductivity with thinner insulation according to embodiments described herein, new thermal management techniques can be created, which can lead to unknown levels of machine performance. Due to the varying conditions regarding the thermal properties of the diamond insulation according to embodiments described herein, the heat flow design in the electrical machine can be done in a way not previously possible and in a more efficient way.

Belt

The insulating layer(s), in particular the diamond containing insulating layer(s), illustrated exemplarily and simplified in fig. 2 to 4, may be realized in different ways, which will be explained in detail below.

According to some embodiments, the diamond containing insulating layer 330 may be provided by tape 210. According to an embodiment, the tape may be wound around the electrical conductor. For example, the tape may include a carrier and diamond particles on the carrier. The diamond particles may be provided as diamond flakes.

Generally, the tape 210 providing the insulation comprises a carrier and diamond particles (as shown and explained in detail with respect to fig. 7) which may be provided as a diamond sheet. According to some embodiments, the diamond sheets are provided on a carrier, thereby forming a ribbon together. According to embodiments, the sheet may have a ratio of sheet thickness to sheet diameter of at least 1:10 and/or at most 1: 10000. The ratio of sheet thickness to sheet length may be 1:5, particularly 1:10, and even more particularly 1: 15. In some embodiments, the ratio of sheet thickness to sheet length is 1:10 or greater. The sheet length extends in a direction of the conductor surface, and the sheet thickness extends perpendicular to the sheet length and the conductor surface. The particles may be distributed non-uniformly and/or uniformly on the carrier or on the surface of the conductor.

The sheet length may be any extension of the sheet in the z-y plane or z-x plane (as illustrated in fig. 6), while the thickness of the sheet may be measured in the x-direction or y-direction (depending on the geometry of the conductor, but in any case perpendicular to the longitudinal axis of the conductor). In the case of wound conductors, the sheet length may be measured as one extension of the sheet in the circumferential direction, while the sheet thickness may be measured in the direction across the insulation. According to embodiments, the diamond particles may be provided as a sheet having a diameter of at least 10 μm and/or at most 1000 μm.

In some embodiments, the strip has a thickness of less than 0.2 mm, particularly less than 0.1 mm, and even more particularly less than 0.02 mm. The thickness of the tape may be measured perpendicular to the longitudinal direction of the tape (z-direction).

In some embodiments and as shown in fig. 5, the tape is wound around the conductor in a spiral manner in the winding direction W. In general, the winding direction W may substantially correspond to the longitudinal z-direction of the conductor arrangement.

In some examples, each wrap of the spirally-wound film may include a portion that overlaps with a previous portion of the insulator or tape itself already present on or around the conductor. In some embodiments, the tape may be a multi-layer tape. Additionally or alternatively, the two or more films used to form the insulation may be helically wound on top of one another, for example by continuously winding the film on the conductor (and/or the insulator already present on the conductor) or by alternatively winding the film on the conductor and/or the insulator already present on the conductor.

According to an embodiment, the belt comprises a first zone and a second zone arranged as strips extending parallel to each other in the longitudinal direction of the belt (as illustrated in fig. 11a to 11 d). The first and second regions differ in diamond content and/or at least one of thermal conductivity and dielectric strength. The first region may include diamond particles and/or the second region may include substantially no diamond particles. For example, the second region may include a higher amount of mica particles and/or a lower amount of diamond particles than the first region. According to an embodiment, the tape may comprise more than 5% mica by volume (volume mica). For example, the tape may include more than 5% mica by volume, but less than 50% mica by volume.

According to an embodiment, the strip is wound around the conductor with a plurality of turns, in such a way that two subsequent turns at least partially overlap each other, in such a way that one of the first and second regions of the two subsequent turns overlap each other and/or in such a way that the other of the first and second regions does not overlap between the two subsequent turns. There may be substantially no overlap of the different regions of two subsequent turns. The overlap may be less than 80% of the strip width, preferably less than 50%.

For example, the tape may be divided into three strips (as illustrated in fig. 11 a), where two strips may comprise mica flakes and one strip may comprise diamond particles. The strip may be arranged on a carrier. According to embodiments described herein, the tape may be wound around the conductor, e.g. two similar strips overlapping each other. A pattern may be formed in which the mica strips and the diamond strips follow each other in sequence. According to embodiments described herein, the diamond particles may provide a substantially continuous thermal path across the insulation through the diamond containing layer and preferably through the electrical insulation. As can be appreciated by those skilled in the art, the tape may not be limited to the number of strips described in this embodiment. It is quite possible to include as many different contents of bars as desired. For example and in accordance with this embodiment, the two regions may be discontinuous (as illustrated in fig. 11 d). The two regions may also be arranged in a pattern in the longitudinal direction of the belt.

With embodiments comprising a tape comprising a diamond containing insulating layer, a winding insulation having a long lifetime and a high thermal conductivity can be provided. Thus, the tape insulation may comprise a carrier and diamond in the form of diamond particles, which may be provided as a sheet and/or diamond powder.

As mentioned above, embodiments with tape also allow for thinner and better thermal conduction insulation using known, easily applied tape insulation techniques. All of the benefits of diamond insulation may be provided in a rapidly achievable form for short to long term use. Diamond based winding insulation refers to the replacement of previously used materials by materials with better thermal conductivity and suitable dielectric strength.

The insulation 203 may comprise a diamond-containing insulating layer 330 and a carrier 310 and diamond particles 320 (as illustrated in fig. 5 and 6) which may be provided as diamond platelets on the carrier 310. In general, diamond sheet 320 forms a diamond containing insulating layer 330 of the insulation of the conductor arrangement according to embodiments described herein. According to some embodiments, the carrier 310 may be a mesh or a membrane. In some embodiments, the carrier 310 may comprise a material such as a (non-woven) polyester mesh, a polyester film, a glass cloth, a non-woven glass cloth, a polyimide, and the like.

The diamond particles 320, which may be provided as a diamond table, may have a greater extension in the z-direction substantially parallel to the conductor surface than in the y-direction corresponding to the thickness of the table substantially perpendicular to the conductor surface. As described above, the diamond containing insulating layer 330 of the insulating portion 203 does not provide a direct path for electrons to pass through the layer. For example, when it is desired to travel through an insulating layer, electrons will need to travel in a zig-zag fashion between sheets. The result is a much higher electrical resistance than the known insulation of electrical conductors. Providing diamond in the shape of a sheet as described in embodiments herein can substantially limit the flow of electrons through the insulator, for example similar to a diamond layer having a continuous surface with substantially no pores on the surface.

According to an embodiment, the diamond particles are arranged in a continuous layer of diamond particles parallel to the conductor surface in an at least partially staggered manner, such that no direct straight-line discharge path through the diamond containing insulating layer is allowed. The diamond particles may contact each other to form a macroscopically interconnected network extending along the surface of the conductor.

It will be understood by those skilled in the art that all embodiments described in terms of bands may also be combined without bands and/or other embodiments.

Insulation layer containing diamond

According to some embodiments, the diamond containing insulating layer surface may be a continuous closed diamond surface. For example, the diamond may be provided as a coating, which results in a continuous closed diamond surface. According to an embodiment, the diamond particles may protrude from the diamond containing insulating layer. Different embodiments for forming the diamond containing insulating layer will be explained in detail below.

The diamond containing insulating layer may be applied by any of tape, vapor deposition, sputtering, extrusion, placing of a separate diamond mass, and the like. The diamond particles may be directly immersed in the conductor.

It will be appreciated by those skilled in the art that the diamond particles provided as diamond powder are provided continuously in the carrier material.

According to some embodiments described herein, the diamond particles are provided as diamond powder 331 having a diameter as defined herein of at least 1 μm. In particular, the size of the diamond powder may be measured as the diameter of the diamond particles in any direction in a plane parallel to the conductor. According to some embodiments, the size of the diamond particles is measured as a diameter in any one of the x-direction, y-direction or z-direction of the conductor arrangement. In some embodiments, the size of the diamond particles of the diamond powder may be measured substantially parallel to the surface of the conductor.

According to one embodiment, the diamond mass has a dimension of typically about 0.5 mm to about 10 cm, more typically between about 1 mm and about 5cm, and even more typically between about 5mm and about 5 cm. The dimension of the diamond mass may be measured as the diameter of the diamond mass in any of the x-direction, y-direction or z-direction. The carrier material 332 in which the diamond mass is provided may be the same carrier material as described with respect to fig. 8. According to some embodiments, the block may be compressed using diamond powder, particularly as slot insulation for wound conductors. For example, compressed diamond powder blocks are available in various shapes and can be applied as a solid diamond powder block layer as a groove insulator.

It will be appreciated by those skilled in the art that not only diamond blocks may be used as slot insulation, but that all of the embodiments described herein may be used for slot insulation in an electrical machine.

According to some embodiments, the diamond containing insulating layer may also be provided in the form of a diamond coating. For example, the diamond coating may be formed on the electrical conductor by vapor deposition (such as chemical vapor deposition or physical vapor deposition), sputtering techniques, and the like. Using a coating process for providing a diamond containing insulating layer may allow for the formation of both inter-turn and slot insulation applied by chemical vapor deposition techniques. The fully diamond covered windings can be cooled by direct cooling methods to improve, for example, machine performance.

According to embodiments, the closed surface may be realized by a coating process or the like as described above. The diamond containing insulating layer 330 may be formed by direct immersion of a diamond layer on the conductor material or on top of the inter-turn insulation of the conductor. The diamond coating may be considered as diamond particles of at least 1 μm in diameter according to embodiments described herein. According to embodiments which can be combined with any other embodiment described herein, the diamond-containing layer further comprises "diamond-like" carbon structures.

The advantages of the embodiments described above refer to thinner and better thermal conductivity insulation with great potential for life benefits. Not only the benefits in view of the high dielectric strength and thermal conductivity of diamond can be used, but also the potential "permanent" winding insulation from the point of view of the lifetime of the machine. Now, the winding insulation life generally determines the life of the machine in practice. The conductor winding provided with the diamond containing insulating layer can have a strong mechanical protection, which can extend the actual life of the electrical machine to an extreme time extension.

Typically, the diamond containing insulating layer of the insulation of the conductor arrangement according to embodiments described herein may be provided directly on the surface of the conductor. In some embodiments, the diamond containing insulating layer of the insulation may be provided on top of a layer on the conductor, for example on top of the winding insulation of the conductor. For example, the layer between the diamond containing insulating layer and the conductor may be an intermediate layer. The intermediate layer may have a value of electrical conductivity between the value of the conductor and the value of the insulating layer comprising diamond. In some embodiments, the intermediate layer comprises a mixture of diamond powder, a retaining matrix, and/or a metal component, wherein the diamond content of the intermediate layer is less than the diamond content of the diamond containing insulating layer. The diamond content of the intermediate layer may be as low as 0% by volume. The intermediate layer may also include diamond powder. The intermediate layer may be electrically conductive, in particular semiconductive, to improve thermal conductivity. According to an embodiment, the thermal expansion coefficient of the intermediate layer may be between the thermal expansion coefficient of the conductor material and the thermal expansion coefficient of diamond.

In some embodiments, which may be combined with other embodiments described herein, the diamond-containing insulating layer has a diamond content greater than 50% by volume of the diamond-containing insulating layer, and particularly greater than 80% by volume of the diamond-containing insulating layer. In case of a diamond content of more than 65% by volume (e.g. by one of the above discussed embodiments of tape, powder, diamond mass or coating), the main insulation of the electrical conductor may be substantially provided by the diamond containing insulating layer. Typically, the mica content in the diamond containing insulation is between 5% by volume and 50% by volume, in particular more than 10%. The insulating effect of the insulating layer, in particular the insulating layer comprising diamond, is provided for the most part by the diamond in the insulating layer comprising diamond. In particular, it can be said that the partial discharge resistant portion (partial discharge resistant part) of the insulating portion is provided by the diamond-containing insulating layer. The diamond containing insulating layer may have a dielectric strength of 18 MV/m to 2200 MV/m. Preferably, the dielectric strength may have a lower limit of 100MV/m and/or an upper limit of 800 MV/m.

As described above and with respect to the embodiments described herein, the total thickness of the insulating layer may be substantially reduced by the insulating portion including the diamond particles. The total insulation thickness is given by the parameter t_totA description is given. Thickness t of diamond-containing insulating layer_dDescribed by the following formula:

（1）

wherein

Parameter k of equation (1)_dMay be 0.005 and the parameter k_dA preferred upper level of (d) may be 0.025.

The thickness of the diamond containing insulating layer may increase with reduced diamond particle content and/or higher voltage ratings applied to the electrical conductor. Despite the reduced thickness of the insulating layer, no direct discharge path through the diamond particles may be provided. The total thickness may vary depending on the variation of the diamond containing insulating layer. The support may vary depending on the thickness of the diamond containing layer. The carrier may additionally vary depending on the diamond content and/or the size of the diamond particles. The total insulation thickness may vary depending on the carrier.

According to some embodiments, the diamond containing insulating layer acts as a primary insulation of the electrical conductor. Typically, the main insulation is a partial discharge resistant portion of the insulation of the electrical conductor. Typically, a main insulation or main wall insulation is used to insulate the wound conductor at full potential from the stator core at ground potential. Generally, the insulation layer or the diamond containing insulation layer provided in the embodiments described herein is configured to provide a main insulation or main wall insulation of the electrical conductor. According to some embodiments described herein, the suitability of an insulation to be used as a main insulation of an electrical conductor depends inter alia on the AC breakdown strength and the dielectric properties of the pure material.

In some embodiments, the insulation of the conductor may comprise different layers, for example layers having different material properties, such as dielectric strength, thermal conductivity, density, elasticity, and the like. Thus, the diamond containing insulating layer may be the layer of the insulation that is most suitable for achieving the insulating effect (and in particular for the main wall insulation), for example by having the greatest dielectric strength among the layers of the insulation of the electrical conductor and/or the highest partial discharge resistance among the layers of the insulation of the electrical conductor.

According to some embodiments, the diamond containing insulating layer has a thermal conductivity between about 0.2W/mK and about 2000W/mK. A preferred lower limit for thermal conductivity may be 0.5W/mK and/or a preferred upper limit for thermal conductivity may be 1000W/mK. Typically, the thermal conductivity is measured in a direction perpendicular to the surface of the conductor, e.g. substantially perpendicular to the longitudinal direction of the electrical conductor, or in the case of a wound conductor, in a direction across the electrical insulation substantially perpendicular to the longitudinal, circumferential direction of the conductor.

According to some embodiments, the value of the characteristic of the diamond containing insulating layer may be achieved by the diamond containing insulating layer as a whole. For example, the diamond containing insulating layer may comprise a carrier material in which diamond particles or masses are disposed. The carrier material may have an influence on the values stated above. Thus, the values recited above may be an average value across the entire diamond containing insulating layer.

The continuously provided diamond particles can be described as not providing a discharge path through the diamond containing insulating layer, in particular in a direction perpendicular to the longitudinal direction of the conductor (as illustrated in fig. 13). Generally, the diamond particles provided continuously prevent a continuous discharge path through the diamond containing insulating layer (similar to percolation theory). A diamond containing insulating layer with continuously provided diamond particles may be described as acting as an insulator limiting the passage of electrons through the diamond containing insulating layer.

In some embodiments, the continuously provided diamond may force electrons trying to pass through to travel in a zig-zag path, which may impede the passage of electrons through the entire thickness of the diamond-containing insulating layer, particularly the diamond-containing insulating layer. It will be appreciated by those skilled in the art that, in general, the surface of the diamond containing insulating layer or layers need not be unperforated, but that small holes may be present without affecting the properties of the insulation of the diamond containing insulating layer and/or without interrupting the continuously supplied diamond particles.

The presence of diamond particles in the insulating layer may result in a thinner insulating layer by providing similar or even better insulating and thermal conductivity properties compared to state-of-the-art insulating layers.

According to an embodiment, the conductor arrangement may be arranged in the magnetic core 402 of the electrical machine. The conductor arrangement may be part of the slot region 401 by being inserted into a slot between e.g. iron rods. The total insulation thickness may vary depending on the type of insulation. For example, the insulator thickness may be reduced when the insulator includes a higher diamond content. The content of the active material can be increased. The magnetic core 402 may be made of a conductive material such as iron.

According to embodiments, which can be combined with any of the embodiments described herein, the trough area may comprise at least one local heat sink 403. At least one partial heat sink 403 may be disposed within the magnetic core 402. The magnetic core 402 may be ferromagnetic. At least one partial heat sink 402 may be a plurality of heat sinks spaced apart from each other in an axial or circumferential direction of conductor arrangement 200. According to an embodiment, at least one local heat sink is arranged in contact with the conductor arrangement for cooling the conductor arrangement 200. At least one local heat sink may be arranged at a respective axial or circumferential position of conductor arrangement 200. According to an embodiment, the electrical machine comprises a ferromagnetic core 402, and the local heat sink is provided in the magnetic core in direct contact with the conductor arrangement 200. In an example, the local heat sink 403 comprises an air duct provided on a plane substantially orthogonal to the axis of the conductor arrangement 200. Additionally, the local heat sink may comprise an air duct provided in the head portion of the magnetic core and extending substantially along the axis of the conductor arrangement 200.

According to an embodiment, the conductor arrangement 200 may comprise at least one insulating layer. The insulating layer may comprise a diamond containing insulating layer. The diamond containing insulating layer may be provided by tape 210. The band may have a width 406. The tape width 406 may be between 10 mm and 40 mm. Preferably, the lower limit of the strip width may be 20 mm and/or the upper limit of the strip width may be 35 mm. The tape may be arranged with a wrap angle 407 allowing the tape to be guided to at least one of the at least one partial heat sink 402 in a direct manner. The tape may be wound around the conductor with a minimum winding angle of 5 to 60 degrees. Preferably, the lower limit of the winding angle may be 10 degrees and/or the upper limit of the winding angle may be 25 degrees. According to one embodiment, the angular direction may be both one direction overlap and/or back and forth reverse overlap. According to one aspect, the strip includes only one directional overlap. In an example, the diamond containing layer is arranged for conducting heat from the electrical conductor towards the at least one local heat sink 403 in a direction along the insulation of the conductor surface. The arrangement of the strips 210 may enable anisotropic heat flow in a direction along the insulation of the conductor to the at least one partial heat sink 403.

The enhanced heat flow may be achieved by a diamond containing insulating layer (as illustrated in fig. 16). The heat flow may be anisotropic. The slot region 401 may comprise a ferromagnetic core with a yoke extending along a yoke axis, wherein the conductor arrangement 200 is at least partially inserted into the slot region 401. Heat may be transferred to the magnetic core 402 and or to the yoke region 404. In addition, heat may be transferred to the wedge region 405. Heat may be transmitted axially in a direction across the insulation and/or in a direction along the insulation of the conductor arrangement 200. At the yoke region, heat may escape through the yoke air duct 408, which may enhance heat transfer away from the conductor arrangement.

As an example of a new motor design, the motor may comprise a ferromagnetic core with a yoke extending along a yoke axis, wherein the conductors are at least partially inserted into the slot regions. The conductor fills a major portion of the cross-sectional area of the trench region. The cross-sectional area may be substantially perpendicular to the yoke axis. In addition, the electrical insulation may fill only a minimal portion of the cross-sectional area of the trench region.

Use of

According to some embodiments, the use of diamond in an insulating layer for electrical conductors, in particular wound conductors, is provided. The electrical conductor includes a surface and a direction across the surface of the conductor. As described in detail above, for example, diamond is typically provided in a diamond-containing insulating layer comprising diamond having diamond particles with a diameter greater than 1 μm provided continuously in a direction substantially parallel to the conductor surface. According to embodiments described herein, the diamond containing insulating layer comprises greater than 5% and less than 50% by volume mica.

As described, for example, in relation to fig. 1, the diamond-containing insulating layer may be used in particular in a winding insulation in a winding of an electrical machine. The use of diamond insulation in the windings of electrical machines is a substantial change in the concept of insulation and enables the improvement of winding insulation with long life and high thermal conductivity. The use of a diamond-containing insulating layer may be achieved via direct immersion of a diamond layer on the conductor surface or on top of the inter-turn insulation, a compressed block of diamond powder as a slot insulation, with the tape insulation made of diamond particles which may be provided as a diamond sheet and/or diamond powder. Variations of embodiments of the diamond containing insulating layer are also described with respect to fig. 5-10.

By using a diamond containing insulating layer according to embodiments described herein, a thinner and better thermal conductive insulation can be provided with great potential lifetime benefits. Not only can the benefits of the high dielectric strength and thermal conductivity of diamond be considered, but also potentially almost "permanent" winding insulation from the current machine life perspective. Thus, new motor designs may be developed that take advantage of higher efficiencies and/or energy densities. Due to better dielectric strength (smaller insulation thickness) and thermal conductivity, a new motor concept can be achieved by the embodiments described herein. With new freed space for more copper or iron and/or with new opportunities for thermal management, new high efficiency (cooler operation) and/or high energy density (greater current experienced thermally) electrical machines can be developed.

Alternatively, a thinner high performance diamond insulation can be used to develop a higher voltage level machine with the same insulation thickness. A combination of increasing the active material content and the voltage level is also possible by a combined use of the freed insulating material space.

Typically, diamond has a dielectric strength of up to about 2000 MV/m (from about 18 MV/m to about 2000 MV/m), while mica has a dielectric strength of up to about 118 MV/m. This difference may result in the diamond layer being thinner than below (1/16.9) the corresponding mica layer 1/10 with the same dielectric strength. The medium voltage mica tape insulation has a thickness of 2.5 mm on both sides of the winding. A corresponding diamond containing insulating layer having equivalent dielectric strength can be provided with a thickness of 0.15mm according to embodiments described herein.

Conversely, the amount of diamond used to replace a certain amount of mica would be less than 1/10 (a factor of 1/16.9 discussed above) in terms of mass times the density ratio. In particular, the density of diamond is 3510 kg/m³And the different mica types are from 2700-³With the variation, using the most conservative ratio of 3510 to 2700 kg, the mass can be used as m_dInstead of diamond of given mass m_mMica of (2), wherein m_dBim_mSmall f =16.9 × 2700/3510, which is about 13. Thus, m_m.=f*m_dAbout 13 × m_d. Thus, a significant total insulation thickness reduction is possible with straightforward simple implementation of existing industrial safety factors. In addition, with mica or other typical insulating materialsThe discharge resistance of diamond is greatly increased compared to that of diamond.

According to some embodiments, the beneficial properties of diamond are caused by the physical properties of diamond. For example, when diamond is bombarded with energetic particles, unlike other materials (e.g., mica), the material structure remains unaffected and no "damage channels" are created through the material. In fact, diamond conducts heat away from the impingement channel so quickly that the incoming energy cannot stay there to destroy the material structure.

Typically, thermal expansion in the slots of the windings in the electrical machine according to embodiments described herein has to be considered. For example, the interface between the conductive material and the diamond may be considered when using the embodiments described herein, especially with respect to different thermal expansion behavior.

Although the present invention has been described based on some preferred embodiments, those skilled in the art will appreciate that these embodiments should in no way limit the scope of the present invention. Any variations and modifications of the embodiments, without departing from the spirit and concept of the invention, should be within the purview of those skilled in the art and those having ordinary knowledge in the art, and thus fall within the scope of the invention as defined by the appended claims.

Claims

1. Electrical machine (100) with a conductor arrangement (200), the conductor arrangement (200) comprising an electrical conductor (201) and an electrical insulation (203) provided at least partially around the conductor (201), wherein

The electrical machine (100) is adapted to apply a voltage up to a rated voltage Vmax to the conductor arrangement (200);

the electrically insulating part (203) comprises a diamond containing insulating layer (330), the diamond containing insulating layer (330) comprising diamond particles (320) having a diameter of at least 1 μm in a direction substantially parallel to the conductor surface;

the diamond containing insulating layer (330) provides the highest dielectric strength and/or discharge resistance of the electrical insulation; and

the diamond containing insulating layer (330) has a thickness t according to equation (1)_d

（1）

Wherein:

。

2. the electric machine (100) of claim 1, wherein the diamond-containing insulating layer (330) has a dielectric strength of 18 to 2200 MV/m.

3. The electric machine (100) of claim 2, wherein the diamond particles (320) comprise at least one of diamond powder (331), diamond flakes (334), diamond blocks (333), and/or a diamond coating (340).

4. The electrical machine (100) of claim 2, wherein the diamond particles (320) are arranged in a continuous layer of diamond particles parallel to the conductor surface in an at least partially staggered manner such that no direct straight line discharge path is allowed through the diamond containing insulating layer (330).

5. The electrical machine (100) of any of the preceding claims, wherein the inner and/or outer surface of the diamond containing insulating layer (330) is a continuous closed diamond surface.

6. The electric machine (100) of any of the preceding claims, wherein the diamond particles (320) protrude from the diamond containing insulating layer (330) containing substrate.

7. The electric machine (100) according to any of the preceding claims, wherein the diamond particles (320) are directly immersed on the conductor (201).

8. The electric machine (100) of claim 1, wherein the total thickness t of the electrically insulating portion_totDescribed by equation (2):

（2）

wherein

。

9. The electrical machine (100) of any of the preceding claims, wherein the diamond containing insulating layer (330) is provided by a tape (210) having a tape width (406) of 10 mm to 40 mm.

10. The electrical machine (100) of claim 9, wherein the tape (210) is wound around the conductor (201) with a plurality of turns, wherein a turn comprises a first region and a second region, wherein two subsequent turns partially overlap each other in such a way that one of the first and second regions of the two subsequent turns overlaps each other.

11. The electric machine (100) of claim 9, wherein the tape (210) is wound around the conductor (201) with a minimum winding angle (407) of 5 to 60 degrees.

12. The electric machine (100) of claim 9, wherein the belt comprises a first region (350) and a second region (335) arranged as strips extending parallel to each other in a longitudinal direction of the belt (210).

13. The electrical machine (100) according to any of the preceding claims, wherein an intermediate layer (202) is provided between the electrical conductor (201) and the diamond containing insulating layer (330), and wherein the intermediate layer (202) has a diamond content that is substantially zero or less than the diamond content of the diamond containing insulating layer (330).

14. The electrical machine (100) according to any of the preceding claims, wherein at least one local heat sink (403) is arranged in contact with the conductor arrangement (200) for cooling the conductor arrangement (200), and the electrical insulation 203 is arranged for transferring heat from the electrical conductor (201) to the heat sink (403).