Axial-flux electric machine and method for manufacturing same

Abstract

The present invention describes an axial-flux electric machine using a topology provided with a stator positioned between rotors, the stator being provided with winding segments distributed around a shaft, with the aim of optimizing the manufacturing and maintenance of the electric machine, as well as promoting safety and performance by means of a coolant. Specifically, the present invention comprises a stator housing, in which a coolant circulates that touches the winding segments, optimizing heat exchange with the aim of reducing the temperature of the machine due to the heat dissipated by the components of the machine and, consequently, increasing the efficiency of the machine. The present invention pertains to the fields of electric machines and thermodynamics, specifically the cooling of such machines, and to the field of electric mobility, such as electric vehicles.

Description

Descriptive Report of Invention Patent AXIAL FLUX ELECTRIC MACHINE AND ITS MANUFACTURING PROCESS Field of Invention

[0001] The present invention is in the fields of electrical machines and thermodynamics aimed at cooling and efficiency of such machines, and fields of electric mobility, such as electric vehicles. Background of the Invention

[0002] Electric motors have been used for decades for a variety of functions. With the electrification of mobility and the automotive sector, electric motors are one of the main components used for this electrification. Therefore, they are also the subject of study and development to ensure they can increasingly meet market demands.

[0003] Proof of this is the diverse topologies and designs of electric motors that have been used in recent years. Among the most widely used types recently are axial flux motors. In these motors, the magnetic flux between the rotor and stator occurs axially, or parallel to the motor axis. This arrangement often allows for the construction of a smaller motor compared to radial flux motors.

[0004] The articles “Axial flux permanent magnet machines: A new topology for high performance applications", published in 2006, and “Analysis of the Yokeless And Segmented Armature Machine", published in 2007, both authored by T.J. Woolmer et al., introduced a new topology for axial flux electric motors, a topology called YASA (Yokeless And Segmented Armature). A schematic example of the YASA topology is shown in Figure 1. As can be seen, the stator is formed by segments circularly arranged around an imaginary axis, where each segment is equipped with coils that generate a magnetic field by applying electric current. Parallel to the circular stator formed by the segments, two rotors equipped with permanent magnets are arranged, one on each side of the stator, to form a sandwich. An air gap is left between the rotors and the stator, creating a magnetic interaction between them. Rotors are commonly connected to a shaft, which supports them, so that this shaft rotates due to the resultant force generated by the magnetic interaction between the rotor and the stator.

[0005] The YASA topology, as noted in the articles, makes it possible to reduce the size and weight of electric motors and increase torque density and machine efficiency. Since then, this topology has been used in electric vehicles, and developments have been made to employ and adapt motors with this type of topology.

[0006] For example, patent BR1 12013003690-7 describes an electric machine built using the YASA topology, where a two-part housing was developed in injected plastic to house the stator and also serve as a housing for the rotors. The patent also aims to construct the stator housing from a mold of the shoes, which are part of the stator segments, forming pockets around the segments. To achieve this, the segments are retained in these pockets using a plastic overmolding process, forming each of the two housing parts. When the two housing parts are fitted together, a cooling chamber is formed with fluid passing between the pockets of the stator segments. In contrast, the present invention does not use an overmolding process to secure or position the stator segments, nor does it use pockets around the segments to adhere them to the stator housing.

[0007] Patent application BR 1 12023015106-6 A2 presents an axial flux machine having a single support disk that receives wound cores. The support disk is a flat plate having holes, where the wound cores are positioned, and cutouts along the outer periphery of the plate to fit into the recesses on the inner surface of the housing. Unlike the present invention, the centralized positioning of the support disc in relation to the two machine covers, combined with the fitting of the disc cutouts in the housing, makes manufacturing the BR 1 12023015106-6 A2 machine difficult. Furthermore, the construction of the support disc and the housing of BR 1 12023015106-6 A2 requires high precision, requiring cooperation between the cutouts in the support disc and the recesses in the housing.

[0008] Additionally, in general, due to the operation and high torque generated by this type of motor, there is an excessive increase in motor temperature, even considering the dissipation of electrical energy from the electric current circulating in the stator coils. As is known, temperature increases are associated with the efficiency of electric motors. Copper resistance increases with temperature, thus increasing the thermal load generated by the Joule effect as the temperature rises. Efficiency reduction can also occur due to the decreased magnetic performance of the rotor's permanent magnets at high temperatures.

[0009] Therefore, a coil cooling system is required, which promotes temperature reduction in the other motor components in thermal contact. Patent BR112013003690-7, mentioned above, uses a cooling chamber as a cooling system, requiring the coolant to come into thermal contact with all the coils to ensure this cooling reaches the stator segments and rotor magnets. Furthermore, water is the coolant used in patent BR1 12013003690-7, requiring an electrically insulating layer surrounding the coils to separate them from the space where the water circulates. Unlike the present invention, the coolant used in the BR112013003690-7 motor is water, requiring the electrically insulating layer to completely surround the coils.

[0010] Patent application BR 1 12023015105-8 A2 presents an axial flux electric machine having a support disk, as well as the Machine BR 1 12023015106-6 A2, in which wound cores are arranged on the support disc, the wound cores being formed by split cores and split coils. With the wound cores arranged on the support disc, the stator assembly method of the machine BR 1 12023015105-8 A2 uses a mold during resin addition to form continuous, serpentine cooling channels on the sides of the support disc, in addition to the resin encapsulating the support disc and the wound cores. Thus, each cooling channel of BR 1 12023015105-8 A2 passes in close proximity to at least one of the surfaces of the wound cores, without touching the surfaces of the wound cores.However, the aforementioned channels of BR 1 12023015105-8 A2, which do not touch the wound cores, as well as the isolated fluid of BR1 12013003690-7, impair the heat exchange for cooling the machine and, consequently, reduce the efficiency of the electrical machine, which is not to be confused with the present invention.

[0011] Alternatively, patent application BR 1 12016018889-6 A2 presents a cooling system for an axial flux machine with a coolant, such as oil, flowing through the stator housing around the coils. Furthermore, barriers are used to connect some of the coils to the innermost and outer surfaces of the stator housing to force the coolant in the space between the coils to flow toward the inner walls of the housing, and vice versa. However, this solution introduced by BR 112016018889-6 A2 still results in some heat exchange loss, since a portion of the coolant accumulates in the innermost region below the coils and near the barriers, preventing full recirculation of the fluid.

[0012] Also in this context, patent application CN1 15483774A presents the use of an annular component arranged in the inner diameter of the axial flux motor, below the coils, where this component is provided with a partially formed recess in its outer surface. This component has this shape to distribute the refrigerant fluid in the lower region of the coils. coils, theoretically seeking to improve heat exchange. However, the fluid ends up circulating inside this component, reducing direct contact with the coils. Furthermore, this annular component is complex to manufacture, in addition to being formed by two components superimposed during assembly.

[0013] In this regard, the aim is to develop axial flux electrical machines, obtained through simplified assembly, optimizing maintenance and manufacturing of the machine's rotor and stator. Furthermore, to increase machine efficiency, the aim is to develop machine cooling solutions that provide optimal electrical machine performance, ensuring safety and reliability for electrical machine operation.

[0014] Thus, from what can be inferred from the literature researched, no documents were found anticipating or suggesting the teachings of the present invention, so that the solution proposed here has novelty and inventive step compared to the state of the art. Summary of the Invention

[0015] Thus, the present invention solves the problems of the prior art by providing an axial flux electric machine comprising a structure housing a stator provided with wound segments and a heat exchange component, said component interacting with the wound segments. Said structure is optimized by combining previously arranged elements to allow proper interaction between the wound segments and the heat exchange component, in addition to enabling improvements during its assembly and manufacturing.

[0016] In one embodiment, the heat exchange component is a coolant that directly contacts the coiled segments, optimizing heat exchange between the coils in contact with the fluid. Thus, the present invention improves machine performance and safety by providing a fluid with electrical and thermal properties, providing electrical insulation between the coiled segments, in addition to the cooling generated by the fluid. touching the coils to reach the stator segments and other components of the electrical machine, aiming at reliability during the operation of the machine and durability of its components.

[0017] Thus, in a first object, the present invention presents an axial flux electrical machine comprising a stator, which is provided with wound segments, and at least one rotor, in which said electrical machine comprises a structure that houses the wound segments of the stator and at least one heat exchange component, which interacts with said wound segments.

[0018] Another object of the present invention is an electric machine comprising a stator, at least one rotor, and a cooling fluid contacting the stator. Said electric machine comprises a structure formed with a sealed means that allows the circulation of the cooling fluid.

[0019] It is also an object of the present invention, a process for manufacturing an axial flux electric machine comprising the steps of: a) obtaining a structure provided with a housing, lateral supports and internal central support; and b) arranging the wound segments and a heat exchange component with said wound segments inside said structure.

[0020] Another object of the invention is a method of controlling heat exchange in an axial flux motor, said method comprising a step of controlling the temperature of the wound segments, by means of the actuation of a heat exchange component.

[0021] It is also another object of the invention, a transport vehicle comprising at least one drive axle, said drive axle being equipped with at least one electric machine capable of providing traction and generating electrical energy from a drive axle operating mode, in which the electric machine is of the axial flux machine type and has a magnetic profile compatible with a previously known demand for operation of the drive axle in the vehicle. transportation. In this sense, the present invention also allows the magnetic profile of the motor / generator to be dimensioned in a manner optimized for the operation of the drive axle installed in the vehicle.

[0022] The invention also includes an axial flux electric machine, being a motor or a generator, which is provided with a cooling fluid for its cooling.

[0023] These and other objects of the invention will be immediately appreciated by those skilled in the art and will be described in detail below. Brief Description of the Figures

[0024] In order to better define and clarify the content of this patent application, the following figures are presented:

[0025] Figure 1 shows a conventional schematic representation of an axial flux motor using YASA topology.

[0026] Figure 2 shows a perspective view of an embodiment of the electrical machine of the invention.

[0027] Figure 3 shows a simplified exploded view of the embodiment of the electrical machine in Figure 2.

[0028] Figure 4 shows a cross-sectional view of the electrical machine highlighting the presence of the lateral supports (23) and the respective interaction regions (231) with the segments (21).

[0029] Figure 5 shows a top perspective view of the electrical machine with one of the side supports (23) removed, allowing the interior of the machine to be detailed.

[0030] Figure 6 shows a cross-sectional view of Figure 5, detailing the positioning of the segments (21).

[0031] Figure 7 shows a top view of the electrical machine in a section highlighting the positioning of the central support (26) and the presence of the heat exchange component.

[0032] Figure 8 shows an isolated view of the side supports (23) interacting with central support (26).

[0033] Figure 9 shows an internal view of the engine highlighting the positioning of the central support (26).

[0034] Figure 10 shows a detailed view of the central support (26) and the respective functional elements (261) according to this embodiment.

[0035] Figure 11 shows a detailed view of the schematic interaction of the coolant with the functional elements (261) according to this embodiment.

[0036] Figure 12 shows a perspective view of another embodiment of the electric machine of the invention, highlighting the side support (23) when removing a cover (76) and a reinforcement element (60) from one side of the machine housing (50).

[0037] Figure 13 shows a side view of the embodiment of figure 12, highlighting the segments (21) positioned by the side supports (23).

[0038] Figure 14 shows a cross-sectional view of the embodiment of figure 12, highlighting the segments (21) surrounded by the coils (24), forming the wound segments.

[0039] Figure 15 shows a detailed view in relation to Figure 14, illustrating the coolant (51) touching the coiled segments.

[0040] Figure 16 shows an exploded view of an embodiment of the electrical machine of the present invention.

[0041] Figure 17 shows a side view of an embodiment of the electrical machine, highlighting the resin portion (25) when removing the lateral support (23).

[0042] Figure 18 shows a cross-sectional view of the embodiment of figure 17, illustrating a coil (24) wrapped continuously over the segments (21).

[0043] Figure 19 shows another cross-sectional view of the embodiment of figure 17, illustrating a segment (21) surrounded by the coil (24).

[0044] Figure 20 shows a detailed view of Figure 19, illustrating the cooling fluid (51) touching the surfaces of the wound segment disposed between the first portion (251) and the second portion (252) of resin.

[0045] Figure 21 shows a perspective view of an embodiment of the electric machine, highlighting the resin portion (25) by removing the lateral support (23) on one side of the machine.

[0046] Figure 22 shows a side view of the embodiment of figure 21, highlighting the fixing elements (561) of the lateral support (23) arranged on an annular face (56) of the housing (50).

[0047] Figure 23 shows a cross-sectional view of the embodiment of Figure 21. Detailed Description of the Invention

[0048] The following descriptions are presented by way of example and are not limitative of the scope of the invention and will make the objects of this patent application more clearly understood.

[0049] The present invention provides an axial flux electrical machine comprising a stator provided with wound segments designed to interact magnetically with the magnetic elements of the rotor. The electrical machine is formed with a structure housing both the wound segments and one or more heat exchange components, said component interacting with the wound segments. In one embodiment, the axial flux electrical machine of the present invention is made using the YASA topology, comprising a plurality of segments arranged around a shaft and at least one rotor, which interacts magnetically with the stator. The rotor interacts mechanically with the shaft, rotating the shaft when subjected to a force resulting from the magnetic interaction with the stator.

[0050] The aforementioned electrical machine structure has sufficient internal space to position the stator's wound segments and to allow proper operation of the heat exchange component. The structure consists primarily of a housing, side supports, and a central support. internal, such that the side supports are fixed to the housing and the internal central support is connected to the side supports. In one embodiment, said housing comprises an annular face that interacts with or fixes the side supports, such that the side supports are arranged parallel to the annular face and opposite each other in relation to the housing. In one embodiment, the association between the annular face of the housing and the side supports is achieved by means of an adhesive material, such as resin, glue, or structural adhesive, but not limited to these. In another embodiment, the association between the annular face and the side supports is achieved by means of mechanical fasteners, such as screws and rivets, but not limited to these.

[0051] The frame's lateral supports are shaped to match the housing and / or annular face and are arranged adjacent to the coiled segments, so that each lateral support covers the entire area where the segments are positioned on each side of the housing. In one embodiment, the lateral supports are provided with interaction regions with the coiled segments, mechanically interacting with said segments. These interaction regions are formed by a brief recess in the inner surface of the lateral support that aids in the assembly and positioning of the segments, as well as acting as a partial fixation function. Alternatively, the interaction regions are formed by a cutout with a geometry / profile compatible with the coiled segments. In one embodiment, the interaction regions limit the radial displacement of the segments.

[0052] In one embodiment, each side support is formed by a single piece having the aforementioned interaction regions. In another embodiment, each side support is formed by a combination of two or more pieces, each having a specific function in the assembly or operation of the electrical machine.

[0053] Furthermore, in one embodiment, the lateral support material is a polymer composite. In one embodiment, the polymer composite is an SMC. (Sheet Molding Compound), which has mechanical and magnetic properties that favor the interaction between the stator and rotor. Furthermore, SMC has thermal properties that favor energy dissipation for cooling the electrical machine, enabling better machine performance and efficiency. In one embodiment, the side support material is an engineering polymer, such as PEEK, which also meets the thermal, mechanical, and magnetic properties required for attaching the support to the frame and for interaction between the stator and rotor. In another embodiment, the side support material is fiberglass.

[0054] The internal center support is mounted in a more interior dimensional region of the electrical machine, positioned closer to the motor shaft. For reference purposes, the internal center support is positioned in the inner diameter below the wound segments. In one embodiment, the connection between the internal center support and the side supports is achieved through an adhesive material, such as resin, glue, or structural adhesive, but not limited to these. In another embodiment, the connection between the internal center support and the side supports is achieved through mechanical fasteners, such as screws and rivets, but not limited to these.

[0055] Furthermore, the internal central support is provided with functional elements that cooperate with one or more functions in the operation or assembly of the electrical machine of the present invention. Said functional elements interact with the heat exchange component and / or with the segments. For purposes of example, the functional elements are static or mobile, active, passive, or reactive, an integral component of the central support or an additional component integrated previously or subsequently. In one embodiment, the functional elements are means of interaction with the heat exchange component. In one embodiment, the functional elements are static ribs formed on the periphery or outer surface of the internal central support. In another embodiment, the functional elements are dynamic / flexible ribs that interact with the heat exchange component as they are excited or receive mechanical contact. In another embodiment, the functional elements are ribs that house heat exchangers that interact with the heat exchange component, enhancing its action.

[0056] In one embodiment, the functional elements are arranged or formed on the inner central support in positions corresponding to the spacing between each wound segment. Furthermore, the number of functional elements is proportional to the spacing between the segments. This proposed configuration allows the functional elements to assist during the electrical machine assembly process, particularly with regard to the assembly and positioning of the wound segments. In one embodiment, the functional elements extend from the inner central support to a height slightly above the lowest region (near the center) of the wound segments. In another embodiment, the functional elements extend from the inner central support to a height close to or equivalent to the center of mass of the segment.

[0057] Furthermore, the present invention seeks to optimize heat exchange with the wound segments, aiming to improve the operating efficiency of the electrical machine. To this end, a heat exchange component is used, which, for the purposes of the present invention, is any component that can be used within the electrical machine structure and actively or passively performs the function of heat exchange with the segments. In one embodiment, the heat exchange component is an active component that changes its properties through external control. In another embodiment, the heat exchange component is an externally operated electronic component. In another embodiment, the heat exchange component is a coolant that circulates within the electrical machine structure, with circulation performed by an external component, such as a pump.

[0058] The coolant interacts physically / mechanically with the functional elements provided in the inner central support. This configuration of the Functional elements allow fluid circulation to generate turbulence in the region where the functional elements are arranged, preventing or reducing fluid accumulation in the lower region of the coiled segments, since accumulation or improper fluid circulation in these regions results in lower efficiency in the overall heat exchange of the electrical machine. With proper flow control by the component external to the electrical machine, the turbulence generated by the interaction of the fluid with the functional element makes circulation—that is, the exit of the "hot fluid"—post-exchange more efficient.

[0059] For the purposes of the present invention, the coolant comprises at least one certain property, aiming at machine power gains combined with operational safety by meeting conditions for heat dissipation and electrical insulation between the machine's wound segments.

[0060] Therefore, the coolant possesses specific electrical and / or thermal properties, enabling a degree of electrical insulation and / or heat exchange. In one embodiment, the coolant supplied to the machine has high thermal conductivity, resulting in greater heat exchange capacity. In another embodiment, the coolant has low electrical conductivity, resulting in electrical insulation for greater machine performance.

[0061] In another embodiment, the fluid possesses both low electrical conductivity and high thermal conductivity, achieving an optimum efficiency point provided by the machine of the invention. In one embodiment, the fluid is a dielectric fluid.

[0062] For purposes of example, the coolant is an oily fluid comprising certain properties being electrical and / or thermal properties.

[0063] Otherwise, the coolant is doped with particles to achieve at least one certain property. In a embodiment, the said particles achieve certain electrical and / or thermal properties for the fluid.

[0064] Furthermore, in one embodiment, the particle is a nanoparticle. In one embodiment, the coolant is a nanofluid, providing greater heat exchange and, consequently, greater electrical machine performance.

[0065] Additionally, these particles comprise a significant degree of amortization. In the context of the present invention, the term "degree of amortization" should be understood as the extent to which a material presents a predominantly disordered phase, in contrast to predominantly monocrystalline and polycrystalline phases. "Amortization" can be understood as a process of loss of long-range ordering of atoms, molecules, or ions in the crystal structure of a given material, which may also present short-range ordering.

[0066] In one embodiment, said particles comprise a degree of amortization of at least 19%.

[0067] In one embodiment, said particles preferably comprise a degree of amortization of at least 20%, more preferably at least 25%, more preferably at least 30%, more preferably at least 35%, more preferably at least 39%, more preferably at least 40%, more preferably at least 45%, more preferably at least 50%, more preferably a degree of amortization of at least 55%, more preferably at least 60%, more preferably at least 65%, and even more preferably a degree of amortization of at least 70%. In one embodiment, the degree of amortization is at least 71%, more preferably at least 72%, more preferably at least 73%. In a non-limiting embodiment, the degree of amortization is 74%.

[0068] In one embodiment, said particles preferably comprise a degree of amortization of at least 39%, preferably a degree of amortization of at least 55% and even more preferably a degree of amortization of at least 70%.

[0069] Therefore, the present invention addresses the need for cooling temperatures in the thermal cycle of a machine such as a generator or electric motor, in addition to meeting the need for electrical insulation. To achieve this, the coolant is applied to the coiled segments. In one embodiment, the coiled segments are completely immersed in the fluid. In another embodiment, the coiled segments are partially immersed in the fluid.

[0070] Thus, to improve heat transfer from the coolant to the hot parts of the machine, machine structure materials are generally selected to achieve better thermal conductivity and thus reduce thermal resistance losses. By dissipating heat from the machine components through the coolant, the present invention provides a thermal cycling condition for the machine, promoting optimized operating efficiency and longer thermal fatigue life for the machine components, thanks to operation under low temperature variations.

[0071] Based on this, the present invention also provides a method for controlling heat exchange in the regions of highest source temperature in the electrical machine, such as in the wound segments. In one embodiment, the method is implemented in an electronic controller equipped with a previously defined algorithm that, through interaction and controls, actuates the heat exchange component. The actuation of the heat exchange component is defined by controlling the properties of said components, such as electrical and chemical properties, viscosity, temperature, flow rate, etc. In one embodiment, the method is implemented in a pump controller, which controls flow and / or temperature parameters of the coolant circulated within the electrical machine structure.

[0072] It is also an object of the present invention a vehicle of transport or commercial vehicle comprising at least one drive axle, said drive axle being equipped with at least one electric machine capable of providing traction and generating electrical energy from a drive axle operating mode, the electric machine being of the axial flux type and having a magnetic profile compatible with a previously known demand for drive axle operation in the vehicle.

[0073] The invention also includes an axial flux electric machine, being a motor or a generator, which is provided with a cooling fluid for its cooling.

[0074] In one embodiment, the drive axle is used in a road implement and has at least two operating modes: traction mode and power generation mode. The electric machine of the present invention is capable of operating in both modes.

[0075] In one embodiment, to optimize the supply of traction to the axle of a road implement or the generation of electrical energy, the electric machine of the present invention was developed with a magnetic profile compatible with the drive axle's demands. The magnetic profile of the electric machine is related to the combination of materials used with properties that result in power density and torque appropriate to the implement's drive axle needs during operation. This magnetic profile is relative to and results from the structure of the electric machine.

[0076] Furthermore, in one embodiment, the electric machine has nominal power matched to the energy capacity of a battery, which provides electrical power and / or is recharged by the electric machine, depending on the operating mode of the drive axle.

[0077] The present invention is based on the context of axial flux motors, but is not limited to the topologies currently employed, nor even to the arrangements commonly used in motor / generator construction. In this sense, potential new topologies can and should be considered as suitable for using the concept presented here for implementation. In conventional constructions, the stator segments are provided with coils wound along each segment, and the rotors are provided with permanent magnets distributed circularly along the rotor. Without limiting the concept of the invention, this arrangement can be reversed. Thus, it is also possible to adopt, by interpretation, the stator segments being provided with magnetizing components and the rotors being provided with magnetizing elements, these elements being different and interacting magnetically with each other.

[0078] The examples shown here are intended only to exemplify one of the numerous ways of carrying out the invention, without, however, limiting its scope. Example 1 - Electric motor with one-piece side supports

[0079] An exemplary version of the electric motor is shown in figure 2. In this construction, the segments (21) of the stator (20) are provided with coils (24) wound along each segment (21), and the rotors are provided with permanent magnets (31) distributed circularly along the rotor (30). Said coils (24) are fitted directly onto each segment (21), not requiring winding along each segment (21). With this, the coil (24) is wrapped / wound continuously, not being a bipartite coil or divided into more parts.

[0080] From this, structures position the segments (21) associated with the coils (24) forming the wound segments, in addition to positioning the rotors (30) next to the stator (20), forming the machine as a motor or generator. With this, the machine structures are manufactured in certain geometries and with certain materials, aiming to achieve certain thermal and mechanical properties, meeting design requirements for power, torque, rotation, etc.

[0081] For this purpose, the machine of the present invention has a housing (50) that houses its components, having a geometry that is predominantly circular, having an external surface, where hydraulic connectors (53) are fixed, and an internal surface, where a stator housing (20) is positioned next to the rotors (30). The housing (50) has two annular faces (56) being compatible with the arrangement of the stator (20).

[0082] To make the composition of the electric motor clearer, Figure 3 shows a simplified exploded view of the motor, with a reduced number of components to facilitate interpretation. As can be seen, the shaft (40) is arranged in the most central region of the inner diameter of the housing (50), so that the internal central support (26) overlaps it. The stator segments (21) are arranged around the shaft, all of them comprising the wound coils (24). Thus, each lateral support (23) is arranged parallel to the housing (50) and each one fixed to an annular face (56) of the housing (50), forming a shelter for the aforementioned components. Finally, the covers (76) are positioned one on each side of the housing (50), closing the electric motor.

[0083] The side supports (23), as seen, have a circular or annular shape compatible with the annular face (56) of the housing (50), in addition to having a central opening for the passage of the shaft (40). In addition to being fixed to the housing (50), the side supports (23) are fixed to the central support (26). In this example, these fixations are carried out by mechanical components, such as screws, but they can be replaced by other fixing components, such as glue, resin or structural adhesive.

[0084] Furthermore, in this example, each side support (23) is formed in a single piece or parts combined into a single piece, generating a single “part number”. 1', which aims to facilitate the engine assembly process. As can be seen in Figure 4, which shows a cross-sectional view of the engine, the external faces of the supports (23) are predominantly smooth, but may have some kind of roughness or relief as needed. The internal faces are provided with interaction regions (231). with segments (21) arranged to assist in the assembly, operation and movement of the electric motor. These regions (231) are presented along the entire surface of the internal face, spaced and in a quantity proportional to the number of segments (21).

[0085] Furthermore, said interaction regions (231 ) are recesses, i.e., not hollow, with geometry compatible with the geometry of the cross-section of the segments (21 ), so that these regions (231 ) limit or prevent the radial and axial displacement of the segments (21 ). In this sense, on both sides of the engine, the segments (21 ) are conditioned to interact mechanically with the lateral supports (23).

[0086] Figures 5 and 6 show a view of the engine with one of the side supports (23) removed, detailing the annular face (56) of the housing (50), in addition to allowing the visualization of the space formed within the engine structure, where the components are housed. In this space, the heat exchange component is inserted to interact thermally with the coils (24), which, in this example, is a coolant fluid (51), as indicated in figure 7.

[0087] In this configuration, the objective of the association between the side supports (23), the annular face (56) of the housing (50) and the central support (26) is to generate a watertight environment that allows the circulation of the coolant fluid (51), that is, without leaks. For this, the single-piece shape of the side supports (23) assists in this sealing, since it reduces possible gaps for fluid leakage (51) in connection / mechanical junction regions, which may occur naturally or, for example, due to assembly errors. Furthermore, the compatible geometry between the interaction regions (231) and the segments (21) allows for a tighter connection, also reducing any clearance for coolant leakage (51). In addition to manufacturing the machine with high repeatability, the present invention provides ergonomics for fitting the supports (23) and the segments (21).

[0088] Additionally, the electric motor configuration presented in this example may contain the application of resin (25), especially in regions of junction between the components, further increasing the seal. Example 2 - Internal center support with ribs

[0089] The internal central support (26) is the component that overlaps the shaft (40) and is arranged in the lowest / central region of the segments (21). The central support (26) has a substantially annular cross-section with a radius slightly larger than the radius of the shaft (40) and slightly smaller than the internal radius formed by the arrangement of the segments (21). This component can be seen in figures 5 to 7 mounted on the electric motor. Furthermore, in figure 8 it is possible to see the internal central support (26) connected to the two lateral supports (23), where the connection is made with the internal radius of the lateral supports (23).

[0090] In this configuration, it was chosen to use ribs (261 ) distributed along the external surface of the central support (26), in which these ribs (261 ) are functional, static, passive and originally formed in the component during its manufacture. Said ribs (261 ) are positioned in a manner compatible with the existing spacing between the segments (21 ) and, consequently, compatible with the existing spacing between the interaction regions (231 ) of both lateral supports (23). This arrangement aids in the engine assembly process, since there is an alignment and a guide for the appropriate assembly of the segments in the correct positions.

[0091] Furthermore, as seen in figure 9, which shows the central support (26) mounted inside the housing (50), the ribs (261) extend from side to side along the axial surface of the support (26), associating with both side supports (23). In this example, the ribs (261) also have a housing to receive a mechanical fastening component, such as a screw, shown in figure 10. This arrangement allows the side supports (23) to be screwed to the central support (26). Alternatively, the ribs have a non-hollow face for interaction with the side supports (23), so so that the connection between these components is made by glue, resin or structural adhesive. With this, the adhesion material is applied to this interaction face to enable better adhesion with the lateral supports (23).

[0092] As in the previous example, this configuration uses a coolant fluid (51) to cool the coils (24) and any other motor components. As shown in Figure 10, the circulation of the fluid (51) and its impact with the ribs (261) generates turbulence in the region below the coils (24), preventing or reducing fluid accumulation in this region. It was found that the accumulation or improper circulation of the fluid in these regions results in lower efficiency in the overall heat exchange of the electric motor. With proper flow control by an electric motor cooling system, the turbulence generated by the interaction of the fluid with the ribs (261) makes circulation, that is, the exit of the "hot fluid" - post-exchange - more efficient. Furthermore, this arrangement makes it possible to direct the flow of fluid (51) so that it interacts with all or most of the coil surface. Example 3 - Electric motor with side supports in combined parts

[0093] From the concept of the YASA topology introduced in the articles “Axial flux permanent magnet machines: A new topology for high performance applications", published in 2006, and “Analysis of the Yokeless And Segmented Armature Machine", published in 2007, authored by TJ Woolmer et al, and exemplified in figure 1, the present invention was implemented, with the electric machine being schematized and shown from the set of figures attached here.

[0094] The axial flux electric machine of the present invention is realized using the YASA topology, so that the electric machine comprises a stator (20), which is provided with a plurality of segments (21), said segments (21) being arranged around an axis (40), without necessarily touching the axis (40), and at least one rotor (30) that interacts magnetically with the stator (20). The rotor (30) interacts mechanically with the axis (40), so that so as to rotate the shaft (40) when subjected to a force resulting from the magnetic interaction with the stator (20).

[0095] The example machine is an electric motor / generator. Figure 12 shows the stator (20) being housed between two auxiliary supports (23) supported on the sides of a housing (50). In figure 13, the stator (20) is housed between the supports (23) forming a sandwich for fitting segments (21). For this, the internal area of ​​the housing (50) is occupied by the lateral supports (23), so that the auxiliary support (23) is concentric with the housing, arranging the segments (21) spaced circumferentially.

[0096] Additionally, each side support (23), having a circular geometry concentric with the housing (50), is associated with an annular face (56) of the housing (50). The annular face (56) of the housing (50) projects onto the inner surface of the housing (50), forming a circular area to support the side support (23). In this example, each side support (23) is fixed to the annular faces (56) of the housing (50) by means of fastening elements (561), which, in this case, are pins. The housing (50), furthermore, has substantially smooth surfaces, facilitating the manufacture of the machine, as well as its transportation, being manufactured in a single block.

[0097] Furthermore, the lateral support (23) is provided with fitting regions (231) for the segment (21), which are through holes through which the segments partially pass. Each segment (21) is fitted into the lateral supports (23), as can be seen in figures 14 and 15, passing through the through holes aligned between the supports (23). Thus, said auxiliary supports (23) are arranged on the sides of the segments (21), forming a sandwich for precise positioning of the segments (21), whether in the manufacture of the stator (20) or in its maintenance. The motor structure also has reinforcement elements (60) arranged on the external sides of the stator housing (20), fixing the segments (21) in the stator housing (20). Said element (60) is a structural reinforcement for fixing the segment (21) in the stator housing (20), in order to restrict the degrees of freedom of the segments (21) of the stator (20). As can be seen in figure 16, the element (60) is a circular plate fixed on the lateral support (23). Thus, the lateral supports (23) adequately fit the segments (21 ) of the stator (20), limiting radial movement of the segments (21 ), while the elements (60) prevent axial movement of the segments (21 ) in the stator housing (20), so that the combination between lateral support (23) and the reinforcement element (60) operate together for the positioning of the segments (21 ).

[0098] Furthermore, inside the stator housing (20), a resin portion (25) is arranged next to each side support (23), as can be seen in figure 17. Each resin portion (25) fills the respective internal surface of the side support (23), maintaining an empty space between the resin portions (25) for the circulation of the cooling fluid (51). The resin portions (25) provide a sealing of the machine, preventing fluid leaks to the outside of the stator housing (20), as well as infiltration of contaminants or particulates inside the stator housing (20). In this way, the cooling fluid (51) touches at least one of the surfaces of the wound segment arranged between the resin portions (25). Example 4 - Electric motor manufacturing process

[0099] Thus, the present invention presents a manufacturing process for the electrical machine of the example, as can be seen in figure 12, where the two rotors (30) arranged parallel to the side of the stator (20) are suppressed. With this, the segments (21), being arranged around the axis (40), receive the coils (24), where electrical current circulates to generate a magnetic field.

[0100] For this purpose, the enlarged and sectional view in figure 14 shows the stator housing (20) and the stator itself (20) in detail. Each auxiliary support (23) is a flat, circular plate, having through holes for fitting the segments (21) and smaller holes for fitting fastening elements (561) distributed along the internal face (56) of the housing (50), being thus, the auxiliary supports (23) are free of cutouts or recesses that could hinder the manufacture of the support (23) and, therefore, of the stator housing (20).

[0101] Still in figure 14, the segments (21) receive coils (24) which are single plates or formed by continuous windings, facilitating the construction of the stator (20) and avoiding damage in the motor operation.

[0102] From this, figure 15 shows an enlarged view focusing on the coiled segment, illustrating the cooling fluid (51) passing and touching the coils (24) and the busbars (27). In addition, a sealing ring (28) is arranged at the ends of the housing (50).

[0103] Thus, the engine is shown in detail in the exploded view in figure 16. For the engine manufacturing process, the housing (50) is formed in the shape of a ring. From this, first, one side of the engine is mounted on one side of the housing (50) for subsequent mounting of the other side of the engine on the other side of the housing (50). Thus, on one side of the housing (50), an auxiliary support (23) is introduced sliding along the continuous periphery of the inner surface of the housing (50) until reaching the inner faces (56) of the housing (50), where the supports (23) are arranged on the inner faces (56) of the housing (50) by means of fastening elements (561) being pins.

[0104] The process then involves fixing a circular plate (60) on the auxiliary support (23) and fixing permanent magnets (31) on the rotor (30).

[0105] Finally, a cover (76) is attached to each side of the example engine by means of the cover (76) O-ring (28) and fasteners (75).

[0106] From this point on, the process finalizes the manufacture of the machine, assembling the remaining components on the other side of the housing (50). Furthermore, hydraulic connectors (53) are fixed on the external surface of the housing (50).

[0107] After inserting the central support (26) around the shaft (40), the other circular plate (60) and other engine components are placed on the other side of the housing (50), in a mirrored manner, in which the circular plates (60) prevent axial movement of the segments (21).

[0108] Furthermore, as shown in figure 17, a resin (25) is applied inside the stator housing (20), with the aim of increasing the sealing of the stator housing (20), preventing fluid leaks (51). Alternatively, sealing elements can be added, such as sealing rings, to replace the resin portions (25), facilitating maintenance and replacement of segments (21), coils (24) of the stator (20) and other components of the machine.

[0109] For electrical insulation, the coolant (51) of the present invention has low electrical conductivity. Furthermore, as a coolant, the fluid (51) has high thermal conductivity, removing heat from the engine. Thus, the fluid (51) of the invention has the desired electrical and thermal properties for electrical insulation of the coil segments and for efficient heat exchange. These thermal and electrical properties of the fluid (51) optimize the performance of the example engine.

[0110] For use in the example engine, the present invention discloses a fluid as an oil with substances that model thermal and electrical properties, promoting surface conductivities to acquire high thermal conductivity and low electrical conductivity.

[0111] As a result, the fluid (51) cools the wound segments, passing through the coils (24) and between the coils (24) and in thermal contact with the rotors (30).

[0112] To this end, figure 18 shows a cross-section of the motor in the direction of the shaft (40), in which the section passes through the coils (24) and parts of the segments (21).

[0113] In another cross-section passing through segment (21), figure 19 shows that the resin (25) forms empty spaces inside the stator housing (20), with a portion of resin (25) being deposited by gravity on each side of the housing (50). Thus, figure 20 shows an enlarged view, where the coolant (51) is visualized touching the coils (24) and the busbars (27). For this, the resin portion (25) is formed one at a time, so that the motor is positioned lying down for insertion of the resin (25) on one side, forming a first resin portion (251). After curing, the motor is turned over to form the second resin portion (252). Thus, the fluid (51) circulates between two resin portions (251) and (252) formed, entering and exiting through the connectors (53). In addition, a bulkhead (29) divides the inlet and outlet flows of fluid (51) by the inlet and outlet connectors (53). Furthermore, other bulkheads are positioned on the internal surfaces of the stator housing (20) in order to generate turbulence in the fluid (51). For example, such additional bulkheads are placed between the lower ends of adjacent coils (24) near the coupler (26), preventing fluid stagnation between coils (24).Thus, the stator housing (24) is sealed by means of an additional step of associating a portion of resin (25) with the lateral support (23), overlapping at least one surface of the wound segment. The limit of the resin portion (25) is more aligned with the ends of the wound segment, allowing a greater contact area of ​​the fluid (51) with the coils (24) and, consequently, greater heat exchange and cooling of the machine.

[0114] Figure 21 shows the housing (50) without the auxiliary supports (23), highlighting the locks (561) as fixing elements, facilitating the fitting of the auxiliary support and, consequently, the correct positioning of the segments (21) of the stator (20).

[0115] Figure 22 shows a side view of the housing shown in figure 21, illustrating that each resin portion (25) follows the geometry of the auxiliary support (23), preventing fluid leaks (51). Additionally, figure 23 shows a cross-sectional view of the engine, omitting the auxiliary supports (23). Example 5 - Method of controlling heat exchange in an electric motor

[0116] The present invention also proposes a method for controlling the Heat exchange between the electric motor components, more specifically, the coils (24) and the busbars (27), which dissipate the greatest amount of energy. For this purpose, an electronic controller equipped with a previously defined algorithm is used that, through interaction and controls, actuates the heat exchange component. The actuation of the heat exchange component is defined by controlling the properties of said components, such as electrical and chemical properties, viscosity, temperature, flow rate, etc. The algorithm's operating settings are defined based on the type of heat exchange component used.

[0117] When selecting the cooling fluid (51), the method is implemented in a pump controller, which controls flow or fluid volume parameters, based on feedback on the temperature of the fluid leaving the interior of the electric motor.

[0118] The coolant (51) circulates inside the motor, touching the coils (24), aiming at temperature control for optimal performance during operation of the electric machine, both in steady state and in transient state. In addition, the coolant (51) of the invention provides a thermal cycling condition with low temperature variation, enabling longer thermal fatigue life for the components of the electric machine, including preventing occurrences of overpower. Thus, the coils are partially or completely immersed in the fluid (51), depending on the optimum point for cooling and circulation of the fluid (51).

[0119] Those skilled in the art will appreciate the knowledge presented herein and will be able to reproduce the invention in the presented embodiments and in other variants and alternatives, covered by the scope of the following claims.

Claims

Claims 1. Axial flux electric machine comprising a stator (20), which is provided with wound segments, and at least one rotor (30) characterized by comprising a structure that houses the wound segments of the stator (20) and at least one heat exchange component, which interacts with said wound segments.

2. Axial flux electrical machine, according to claim 1, characterized in that the heat exchange component is a cooling fluid (51), in which the structure allows the circulation of the cooling fluid (51), said cooling fluid (51) being in contact with the wound segments.

3. Axial flux electric machine, according to claim 2, characterized in that the structure comprises a housing (50), lateral supports (23) and internal central support (26), said components being associated with each other, so that the association of these components defines a sealed medium that circulates the cooling fluid (51) and houses the wound segments.

4. Axial flux electric machine according to claim 3, characterized in that the lateral supports (23) interact mechanically with the wound segments, in which the lateral supports (23) have interaction regions (231).

5. Axial flux electric machine, according to claim 3, characterized in that the internal central support (26) is positioned in a more internal dimensional region in relation to the wound segments.

6. Axial flux electric machine according to claim 3, characterized in that the internal central support (26) comprises at least one functional element (261) that interacts with the cooling fluid (51).

7. Axial flux electric machine according to claim 6, characterized in that the functional elements (261) are arranged in a corresponding manner with spacings existing between each wound segment.

8. Manufacturing process of axial flux electric machine, said machine electrical comprising a stator (20), which is provided with wound segments, and at least one rotor (30) characterized by comprising the steps of: a. obtaining a structure provided with a housing (50), lateral supports (23) and internal central support (26); and b. arranging the wound segments and a heat exchange component with said wound segments inside said structure.

9. Process, according to claim 8, characterized in that the step of obtaining a structure comprises the steps of: a. associating the lateral supports (23) to the casing (50); and b. associating the internal central support (26) to the lateral supports (23); in which, said associations define a watertight means to house the heat exchange component.

10. Process, according to claim 8, characterized in that the coiled segments are arranged so as to mechanically interact with one or more interaction regions (231) of the lateral supports (23).

11. Process according to claim 8, characterized in that the internal central support (26) is provided with a functional element (261) and is mounted in a dimensional region that is more internal in relation to the coiled segments.

12. Method according to claim 11, characterized in that the coiled segments are arranged with a spacing between them, said spacing corresponding to the positions of the functional elements (261) of the internal central support (26).

13. Method of controlling heat exchange in an axial flux motor, said motor comprising a stator (20), which is provided with wound segments, and at least one rotor (30), characterized by comprising a temperature control step of the wound segments, by means of the actuation of a heat exchange component.

14. Heat exchange control method, according to claim 13, characterized in that the heat exchange component is a cooling fluid (51), in which said cooling fluid (51) is circulated inside a structure that houses the coiled segments, so that the cooling fluid (51) comes into direct contact with the coiled segments.

15. Transport vehicle comprising at least one drive axle, said drive axle being equipped with at least one electric machine capable of providing traction and generating electrical energy from a drive axle operating mode, characterized in that the electric machine is of the axial flux type and has a magnetic profile compatible with a previously known demand for operation of the drive axle in the transport vehicle, said electric machine being as defined in any one of claims 1 to 7.

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