JP2022550460A - Electric motor with improved thermal properties - Google Patents

Abstract

An exemplary stator for an electric motor includes: a lamination stack comprising a plurality of segments arranged adjacent to each other in a radial array; slots formed in segments of the plurality of segments of the lamination stack; , a slot liner configured to be electrically insulating, a thermally conductive gap filler disposed in a gap between the slot liner and the segment, and a winding disposed in the slot. [Selection drawing] Fig. 10

Description

This application claims priority to US Provisional Application No. 62/909,850, filed October 3, 2019, which is hereby incorporated by reference in its entirety.

FIELD OF THE DISCLOSURE The present disclosure relates generally to systems and assemblies including electric motors with improved thermal properties and improved heat transfer to the surrounding environment of the electric motor.

An electric motor is an electric machine that converts electrical energy into mechanical energy. Most electric motors operate by the interaction of the motor's magnetic field with currents in the windings, producing force in the form of rotation of the shaft. An electric motor can be powered from a direct current (DC) source such as a battery, automobile, or rectifier, or from an alternating current (AC) source such as a power grid, inverter, or generator.

The torque and power produced by the motor shaft is limited by the amount of current or power introduced through the windings. If the current increases beyond a certain limit, the temperature of the windings increases and can damage the wires and the electric motor.

Thermal properties have therefore been improved to increase heat transfer from the windings, thereby lowering the temperature of the windings for a given current draw, preventing damage to the motor, and allowing for increased current limits. It may be desirable to have an electric motor. It is with respect to these and other considerations that the disclosure made herein is presented.

This disclosure describes implementations for electric motors with improved thermal properties.

In a first exemplary implementation, this disclosure describes a stator for an electric motor. The stator includes (i) a lamination stack, (ii) slots formed in the lamination stack, (iii) a slot liner disposed in the slot and configured to be electrically insulating, and (iv) a slot liner. (v) windings disposed in the slots;

In a second exemplary implementation, this disclosure describes an electric motor assembly. The assembly includes a stator with an open annular space. The stator comprises (i) a lamination stack comprising a plurality of segments arranged adjacent to each other in a radial array; (ii) a plurality of slots formed between adjacent segments of the plurality of segments of the lamination stack; iii) respective slot liners disposed in the plurality of slots and configured to be electrically insulating; and (iv) disposed in respective gaps between the respective slot liners and the plurality of segments of the lamination stack. and (v) windings disposed in the plurality of slots. The assembly further includes a rotor disposed in the open annular space of the stator and comprising a steel core and a plurality of magnets disposed in respective radial arrays around the steel core.

In a third exemplary implementation, this disclosure describes a method. The method comprises: (i) providing a segment of a lamination stack of an electric motor stator, the segment of the lamination stack comprising a slot; and (ii) a slot liner formed of an electrically insulating material. (iii) adding a thermally conductive gap filler to the outer surface of the slot liner; and (iv) such that the thermally conductive gap filler is disposed between the outer surface of the slot liner and the segment. (v) the slot liner and the thermally conductive gap filler are positioned between the wires and the segments; and winding a wire around the segment as done.

The foregoing summary is merely exemplary and is in no way intended to be limiting. In addition to the exemplary aspects, implementations, and features described above, further aspects, implementations, and features will become apparent by reference to the drawings and detailed description that follows.

The novel features believed to be characteristic of the exemplary examples are set forth in the appended claims. Illustrative examples, however, as well as preferred modes of use, further objects and description thereof, are best understood by reference to the following detailed description of illustrative examples of the disclosure when read in conjunction with the accompanying drawings. would be

1 is a perspective view of an electric motor, according to an exemplary implementation; FIG. FIG. 2 is a perspective view of a stator and a rotor mounted within the stator, according to an exemplary implementation. FIG. 3 is a perspective view of a stator lamination stack, according to an exemplary implementation; FIG. 4 is an exploded view of an insulating slot liner placed in each slot of a lamination stack, according to an exemplary implementation. FIG. 5 is a perspective view of an individual slot liner, according to an exemplary implementation; FIG. 6 is a diagram illustrating components associated with a segment of a lamination stack prior to stator wire assembly and winding, according to an exemplary implementation. FIG. 7 illustrates a segment of a lamination stack after assembling components and winding wires, according to an exemplary implementation. FIG. 8 is a partial cross-sectional view of a segment of a lamination stack, according to an exemplary implementation; FIG. 9 illustrates placement of thermally conductive gap filler in portions of the gap between the slot liner and the segment of the lamination stack and between the cooling tube and the segment of the lamination stack, according to an exemplary implementation; It is a figure which shows that. FIG. 10 illustrates placing a thermally conductive gap filler across the interfaces between the slot liner and the segments of the lamination stack and between the cooling tubes and the segments of the lamination stack, according to an exemplary implementation. FIG. 4 is a diagram showing; FIG. 11 is a flowchart of a method for assembling a stator or electric motor, according to an exemplary implementation;

The torque and power produced by the shaft of an electric motor can be limited by the amount of current or power introduced through the windings of the electric motor. If the current increases beyond certain limits, it can damage the wires and the motor.

Disclosed herein, among other examples, are systems and assemblies related to electric motors with improved thermal and heat transfer characteristics. In particular, the disclosed system uses a thermally conductive gap filler between the winding insulation liner and the lamination stack of the electric motor. A thermally conductive gap filler may also be placed between the electric motor cooling tubes and the lamination stack channels in which the cooling tubes are placed. A thermally conductive gap filler can improve heat transfer from the windings of an electric motor.

The improved heat transfer allows the current limit of the electric motor to be increased, thus allowing the same electric motor to produce higher torque and power. The improved heat transfer also allows the electric motor to run at lower temperatures for a given torque output, thereby increasing the efficiency of the electric motor.

FIG. 1 shows a perspective view of an electric motor 100, according to an exemplary embodiment. Electric motor 100 includes a stator 102 . Stator 102 is configured to generate a magnetic field. In particular, as described below, the stator 102 can include windings wrapped around lamination stacks that generate a magnetic field when current is applied to the windings. Stator 102 may also include mounting locations 103 to allow attachment of electric motor 100 to a machine or device that utilizes electric motor 100 .

Electric motor 100 further includes a rotor 104 . Stator 102 may have an open annular space in which rotor 104 is disposed. Rotor 104 may be fitted with magnets that can interact with the magnetic field produced by stator 102 to rotate and produce torque. Rotor 104 can rotate relative to stator 102 by being attached to stator 102 via bearings 106, for example.

Shaft 108 may be coupled to rotor 104, and shaft 108 transmits torque generated by rotor 104 to, for example, a gearbox or machine component to rotate such component. configured as Electric motor 100 may include another mounting location 109 to further facilitate mounting electric motor 100 to a machine that utilizes the generated torque and resulting rotational motion of shaft 108 .

Electric motor 100 may include other components, such as feedback devices 110 (eg, sensors) that provide sensor information indicative of the position of rotor 104 to an electronic controller of electric motor 100 . The electronic controller can then energize the windings of stator 102 at the appropriate times to achieve the desired torque.

Cable 112 may be used to supply current to the windings of stator 102 . Cable 112 can also be used to transmit electrical signals generated by feedback device 110 to indicate the position of rotor 104 to the amplifier.

FIG. 2 illustrates a perspective view of assembly 200 of stator 102 and rotor 104 mounted within stator 102, in accordance with an exemplary embodiment. Stator 102 may have a steel core. Stator 102 may include a lamination stack. The lamination stack can be made as a single piece (eg, unitary construction) or can comprise multiple segments, as described below with respect to FIG.

The electrical wire is wrapped around the segments of the lamination stack. For example, FIG. 2 shows individual coils (bundles of wire) such as coil 201 wound on a segment of stator 102 . The coils are separated from each other to prevent the occurrence of electrical shorts. When current is provided to the wire, the coil can act as an electromagnet and generate a magnetic field.

Rotor 104 may also have a steel core. Rotor 104 may further have a plurality of magnets (eg, permanent magnets) such as magnet 202 arranged in a radial or circumferential array around the steel core of rotor 104 .

The current provided to the coils of stator 102 may be provided to individual coils of each segment of stator 102 in a particular sequence. In this way, the magnetic fields generated by the stator coils can effectively move or change in a circular fashion around the stator 102 . The magnetic field interacts with the magnets of rotor 104, and such interaction of the magnetic field with the magnets causes rotor 104 (and shaft 108 coupled thereto) to rotate.

FIG. 3 shows a perspective view of a lamination stack 300 of stator 102, according to an exemplary implementation. As shown in FIG. 3, the lamination stack 300 is generally doughnut-shaped and has an open annular space 302 in which the rotor 104 can be positioned. The lamination stack 300 comprises laminated electrical steel sheets. Lamination is a technique/process of manufacturing materials in multiple layers such that the composite material achieves improved strength, stability, sound insulation, appearance, or other desirable electrical properties.

The lamination stack 300 is made of silicon steel, also known as electrical steel, which comprises steel with added silicon. Adding silicon to steel increases electrical resistance, improves the ability of magnetic fields to penetrate steel, and reduces hysteresis losses in steel. Lamination stack 300 represents the core of stator 102 and is laminated and insulated to reduce induced circulating currents and associated heat when current is modulated by the windings of stator 102 .

In an example, the lamination stack 300 can be made as a single piece or component that is not segmented. For example, the lamination stack 300 can have teeth similar to gears and can be configured to receive a wire through the slots or spaces between the teeth.

In another example, lamination stack 300 includes a plurality of segments, such as segment 304, segment 306, and segment 308, arranged adjacent to and abutting each other in a radial array. The segment is generally formed or shaped as an I-beam with C-shaped side channels or slots on either side of it. Thus, when two adjacent segments abut each other, a slot is formed between them, comprising the C-shaped channel or respective slot of the two adjacent segments. For example, slot 310 is formed between segments 304 and 306 and slot 312 is formed between segments 306 and 308 . Although the following description refers to a multi-segment construction of lamination stack 300, similar descriptions apply to lamination stacks having a unitary construction and made as a single, non-segmented component. Please understand. Such components may have holes, channels or slots similar to slots 310, 312 made therein to receive slot liners described below.

Each of the slots 310, 312 comprises one slot (partial slot) formed in one segment of the lamination stack 300 and a second slot (partial slot) formed in an adjacent segment of the lamination stack 300. . The term "slot" is used herein to refer to a complete slot, such as slot 310 or slot 312, as it refers to an individual slot or partial slot (C-shaped channel) of a segment of a lamination stack. Also used for The wire is wound into slots in a lamination stack 300 of wire bundles or coils, such as the coil 201 shown in FIG.

When current is applied to the wire, the temperature of the wire increases and heat is generated. Heat is sometimes called winding losses. Heating up the wires can cause damage and limit the performance of the electric motor 100, as explained below.

In an example, the lamination stack 300 can be liquid cooled to cool the lamination stack 300 and the wires disposed therein. As illustrated in FIG. 3, each segment can have a channel disposed therein that is semi-circular in shape. For example, segment 304 has a semi-circular channel 314 longitudinally disposed across the outer circumference of segment 304 . Tubes can be placed through the semi-circular channels 314 and cooling fluid can be provided through such tubes, thereby absorbing some of the heat generated by the wires and allowing the lamination. Cool the stack 300 and the wires placed therein.

The coils of stator 102 are individually energized as described above to produce a moving or varying magnetic field. Therefore, it is desirable to electrically insulate the wires of the coils from the lamination stack 300 to prevent short circuits or electrical connections between the wires of two adjacent coils. To isolate the wires from the segments of the lamination stack 300, insulating liners can be placed in the slots of the lamination stack 300 to act as electrical insulators. For example, a paper liner can be used as an insulating liner.

FIG. 4 shows an exploded view of insulating slot liners disposed in respective slots of lamination stack 300, and FIG. 5 shows a perspective view of individual slot liners 500, according to an exemplary implementation. The slots of the lamination stack 300 can receive therein respective insulating paper slot liners shown in the radial array of FIG. For example, insulating paper slot liner 400 can be inserted into slot 310 and insulating paper slot liner 402 can be inserted into slot 312 . In an example, the insulating paper slot liner may consist of two separate slot liners, each slot liner of the two separate slot liners may have a U-shape or a C-shape so that they are When they meet at the lateral edges, slots or channels are formed between them through which the wires of the coils of stator 102 are placed.

FIG. 5 shows an example of such a slot liner 500. As shown in FIG. The slot liner 500 can have a first side 502 , a second side 504 , and a connection 506 that couples or connects side 502 to side 504 . With this configuration, slot liner 500 forms a channel therein (eg, a C-shaped channel).

Two slot liners similar to slot liner 500 are placed such that the respective edges of the side portions of the slot liners abut each other (i.e., with their respective C-channels positioned in between, rather than the connections abutting each other). , or rather opposite each other) to form the insulating paper slot liner of the insulating paper slot liner shown in FIG. A slot liner (eg, slot liner 500 ) may be individually inserted into each segment slot of the lamination stack 300 .

In another example, the insulating paper slot liners 400, 402 can be made as a single rectangular liner rather than two separate slot liners. In yet another example, rather than having separate insulating paper slot liners, such as insulating paper slot liners 400 and 402, slot liners for the entire lamination stack 300 go around and line respective slots of the lamination stack 300. Can be created as a single component.

FIG. 6 shows components associated with segment 600 of lamination stack 300 prior to stator 102 assembly and wire winding, according to an exemplary implementation. Segment 600 may represent any of the segments of lamination stack 300 (eg, any of segments 304, 306, 308).

As noted above, a segment of lamination stack 300 is generally formed or shaped as an I-beam with C-shaped channels on either side thereof. Segment 600 can have a first slot or channel 602 and a second slot or channel 604 . A first slot liner 606 can be positioned in the first channel 602 and, likewise, a second slot liner 608 can be positioned in the second channel 604 . Slot liners 606 , 608 may also be C-shaped to match the shape of channels 602 , 604 of segment 600 . As the wire is wound around segment 600, slot liners 606, 608 insulate the wire from the sides of segment 600 (ie, the surfaces of channels 602, 604).

The slot liners 606, 608 may not extend to the end of the segment 600 and may not isolate the end face of the segment 600 from the end turns of the wire as the wire wraps around the end of the segment 600. To insulate the end-turns of the wire, a first end-turn insulation 610 can be inserted into the first end of the segment 600 and a second end-turn insulation 612 can be inserted prior to winding the wire. It can be inserted into the second end of segment 600 .

FIG. 7 shows segment 600 after assembling its components and winding wire 700 according to an exemplary implementation. A slot liner, such as slot liner 606 , is placed in each channel of segment 600 and end-turn insulators 610 , 612 are also inserted into each end of segment 600 , as shown in FIG. 7 . Wire 700 can then be wrapped around segment 600 to form a coil associated with segment 600 .

With this configuration, wire 700 is electrically insulated from segment 600, so that when multiple segments of lamination stack 300 are assembled into a radial array to form lamination stack 300, their respective coils are in contact with each other. electrically insulated. Additionally, the wires can be coated with an electrically insulating material (eg, a synthetic polymer such as nylon polyamide) to isolate the individual wires of a given segment from each other and prevent electrical shorting.

When inserted into channels 602 , 604 , the outer surfaces of slot liners 606 , 608 can contact the inner surfaces of segments 600 of lamination stack 300 . However, a gap may separate the outer surface of slot liners 606 , 608 and the inner surface of segment 600 .

FIG. 8 shows a partial cross-sectional view of segment 600, according to an exemplary implementation. As shown in FIG. 8, when the slot liner 606 is inserted into the channel 602 of the segment 600, the gap 800 forms the outer surface of the side portions (eg, side portions 502, 504) and the connection portion (eg, connection portion 506). can be separated from the inner surface of the channel 602 of the segment 600 where the slot liner 606 is located.

As described above with respect to FIG. 3, each segment of the lamination stack 300 can have a semi-circular channel disposed therein for receiving a cooling tube. For example, segment 600 can receive cooling tube 802, as shown in FIG. Another gap 804 may separate cooling tube 802 from the inner surface of segment 600 bounding the semi-circular channel in which cooling tube 802 is disposed.

When electrical current is provided through the wires of electric motor 100 (eg, wires 700 ), heat is generated, which can increase the temperature of the components of electric motor 100 . The heat generated from the wires or coils of electric motor 100 can be referred to as winding losses and can be determined based on the magnitude of the wire's current (I) and electrical resistance (R). In particular, winding losses can be determined as ^I2R .

In addition, the heat generated (winding losses) can be converted into electrical It can be transmitted to the surrounding environment of the motor 100 . In particular, heat transfer is defined by the following equation,

can be determined by

For a given ambient temperature Ta, electrical resistance R, and winding-to-ambient thermal resistance Rthwa, equation (1) shows that the winding temperature Tw is proportional to the square of the current ( ^I2 ) . During operation of the electric motor 100, the winding temperature Tw may damage the electric motor 100 if it exceeds a threshold level. For example, the wire coating (eg, polyamide coating) can be damaged, causing individual wires of a coil or winding to contact each other and create an electrical short.

To prevent damage to electric motor 100, the magnitude of current (I) is limited to prevent winding losses from exceeding a certain level and winding temperature Tw from exceeding a threshold level. However, limiting the magnitude of current (I) can also limit the magnitude of torque that electric motor 100 can produce. In particular, the torque (T) produced by the electric motor 100 can be determined as T=K _t I, where K _t is the motor torque constant, the length of the stator 102 and the number of wire turns based on a constant multiplied by The power (P) produced by electric motor 100 can be determined as P=Tω=K _t Iω, where ω is the rotational speed of rotor 104 or shaft 108 coupled thereto.

Therefore, limiting the magnitude of current I also limits the torque T and power P that electric motor 100 can produce. Further, at a particular power level, the amount of heat generated affects the efficiency of electric motor 100 (eg, the ratio of power P produced by electric motor 100 divided by power provided to electric motor 100). may affect By operating the electric motor 100 at a lower winding temperature Tw for a particular power output P, the efficiency of the electric motor 100 can be increased.

The slot liners discussed above (eg, slot liners 500, 606, 608) are configured to be electrically insulating, but may not be thermally conductive, thus providing higher thermal resistance to the environment. and can interfere with heat transfer from the wire to the environment. In other words, a slot liner that is not configured to be made of a thermally conductive material can increase Rthwa. Additionally, if there is a gap (eg, gap 800) between the slot liner and a segment of the lamination stack, the gap may fill with air, which can further increase Rthwa.

One approach to allowing electric motor 100 to receive higher current (I) without damaging its components involves reducing the winding-to-ambient thermal resistance (Rthwa). Based on equation (1) above, by reducing Rthwa, the winding temperature Tw can be maintained at a certain level for higher currents (I), so that the electric motor 100 is , allowing higher torque (T) and power (P) production without damaging its components. Alternatively, the same current level (I) can be used and the electric motor 100 can produce the same torque (T) and power (P) while reducing the winding temperature Tw, whereby the electric motor 100 increase the efficiency of

In an example, reducing the winding-to-ambient thermal resistance (Rthwa) reduces heat transfer to the gap between the slot liner (e.g., slot liner 606) and the lamination stack 300 (e.g., at gap 800). This can be achieved by placing a reactive gap filler. Additionally or alternatively, a thermally conductive gap filler can be placed in the gap between the cooling tube (eg, cooling tube 802) and the lamination stack 300 (eg, at gap 804). Such thermally conductive gap fillers can reduce thermal resistance (resistance to heat flow from the windings to the lamination stack 300 and then to the environment), thus reducing Rthwa.

In an example, a thermally conductive gap filler can be disposed in or line a portion of each gap (eg, gap 800 and/or gap 804). In other examples, a thermally conductive gap filler can be used to fill the entire interface between the slot liner and the lamination stack 300 and the interface between the cooling tubes and the lamination stack 300 .

FIG. 9 illustrates placing a thermally conductive gap filler in portions of gap 800 and gap 804 according to an exemplary implementation. As shown in FIG. 9, the thermally conductive gap filler 900 (indicated by dashed lines) is the portion between the connection (e.g., vertical portion) of the slot liner 606 and the inner surface of the segment 600 of the lamination stack 300. can be placed in Each thermally conductive gap filler 902 (indicated by a curved dashed line) fills the gap 804 between the outer surface of each of the cooling tubes 802 and the inner surface of the semi-circular channel of the segment 600 in which the cooling tubes 802 are disposed. It can also be placed in part.

In an example, the thermally conductive gap fillers 900 , 902 can be placed in the segments 600 of the lamination stack 300 prior to inserting the slot liners 606 and cooling tubes 802 . Alternatively, thermally conductive gap fillers 900 , 902 may be applied to the outer surfaces of slot liner 606 and cooling tubes 802 prior to insertion into their respective channels of lamination stack 300 .

FIG. 10 illustrates placing thermally conductive gap filler across the interface between slot liner 606 and segment 600 and between cooling tube 802 and segment 600, according to an exemplary implementation. As shown in FIG. 10, the thermally conductive gap filler 1000 (indicated by dashed lines) is applied to the sides and connections of the slot liner 606 and the inner surface of the segment 600 bounding the channel in which the slot liner 606 is disposed. or along the sides and connections of the slot liner 606 and the inner surface of the segment 600 bounding the channel in which the slot liner 606 is disposed. A thermally conductive gap filler 1002 (indicated by the curved dashed line) can also be placed across the gap 804 between the cooling tube 802 and the inner surface of the semi-circular channel of the segment 600 in which the cooling tube 802 is placed. .

9-10 show one side or half of segment 600 and show partial cross-sections using thermally conductive gap filler for a portion of segment 600. FIG. However, it should be understood that the thermally conductive gap filler can be used on the opposite side of segment 600 and can be used with all or some of the other segments of lamination stack 300 . Additionally, as discussed above, the thermally conductive gap filler can be placed in the segments of the lamination stack 300 prior to inserting the slot liners 606 and cooling tubes 802, or the thermally conductive gap filler can be , can be applied to the cooling tubes (eg, cooling tube 802) and slot liner (eg, applied to sides 502, 504 and connection 506 of slot liner 500) prior to insertion into their respective channels.

Various types of thermally conductive fillers can be used. For example, the thermally conductive filler can take the form of a paste comprising mineral oil in which thermally conductive solid particles (eg, metallic material) are suspended. In another example, the thermally conductive filler can take the form of a thermally conductive pad comprising a silicone polymer combined with a heat carrier (eg, ceramic).

By way of example, the thermally conductive gap filler can include silicone grease or wax filled with a thermally conductive material such as aluminum oxide. Such silicone greases can take the form of semi-liquid or solid materials at normal room temperature, liquefy or soften at elevated temperatures and flow between the slot liner and segments of the lamination stack 300 or as they cool. It conforms well to any irregularities in the interface between the tube and the lamination stack 300 . In some examples, the silicone grease or wax can be provided in the form of a thin film. A substrate, web, or other carrier can be provided for providing such thin films.

In another example, the thermally conductive gap filler can comprise a cured sheet of material. Such materials can be formulated to include one or more thermally conductive particulate fillers dispersed within a polymeric binder and can be provided in the form of cured sheets, tapes, pads, or thin films. . Exemplary binder materials include silicones, urethanes, thermoplastic rubbers, and other elastomers, and exemplary fillers include aluminum oxide, magnesium oxide, zinc oxide, boron nitride, and aluminum nitride.

In another example, the thermally conductive gap filler comprises a cured, form-stable, sheet-like, thermally conductive material for transferring thermal energy from the windings and lamination stack 300 to the environment. can be done. Such materials can be formed from a urethane binder, a curing agent, and one or more thermally conductive fillers. Fillers can include aluminum oxide, aluminum nitride, boron nitride, magnesium oxide, or zinc oxide, and can range in particle size from about 1 to 50 microns, or can include nanoparticles, for example.

In an example, the thermally conductive gap filler can include a phase change material, which can be self-supporting and shape-stable at room temperature for ease of handling. Such phase change materials can liquefy or otherwise soften at temperatures within the operating temperature range of electric motor 100 to form a viscous, thixotropic phase, which can be seen between the slot liner and segments of lamination stack 300 . or at the interface between the cooling tubes and the lamination stack 300. The phase change material, which can be supplied as a free-standing thin film or as a heated screen printed on the surface of a substrate, can be maintained within the operating temperature of electric motor 100 under relatively low clamping pressures of about 5 pounds per square inch (psi). can act as greases and waxes that conform and flow in the

In another example, the thermally conductive gap filler can include a tape or sheet with inner and outer release liners and an intermediate layer of thermal compound. One side of the tape or sheet is coated with a thin layer of pressure sensitive adhesive (PSA) to attach the material to the heat transfer surface between the slot liner and the segments of the lamination stack 300 or between the cooling tubes and the lamination stack 300. can be applied.

Other exemplary thermally conductive gap filler materials can include thermal interface compounds, caulks, in-place forming materials, or encapsulants. These materials cure at room or elevated temperatures to form in-place a gap (e.g., gaps 800, 804) in a one- or two-part liquid or otherwise flowable filled reaction system. As, one or more tubes, provided filled in a container.

In another example, the thermally conductive gap filler can comprise a thermally conductive compound that is dispensable under applied pressure when discharged from a nozzle or other orifice as a bead or clump. Materials that may be filled into tubes, cartridges, or other containers may be dispensed onto the surfaces of slot liners or cooling tubes, which form gaps (eg, gaps 800, 804) with segments of the lamination stack 300. or directly into the gap formed between adjacent surfaces. When applied, the material can form a bead or clump of material "in-place." Within the gap, the in-place formed bead or mass of material at least partially fills the gap, thereby providing a thermal conduction path between the surfaces and reducing the winding-to-ambient thermal resistance (Rthwa). can function as an interface material that is adapted to In an example, the material can be fully crosslinked or otherwise cured to be filled or otherwise dispensed into a tube, cartridge, or other container. While of flowable viscosity, the material may generally be viscoelastic and may not exhibit appreciable sedimentation of the metal filler particles when filled.

The thermally conductive compound can be thermally conductive particles or mixtures thereof, such as a blend or mixture of (i) a polymer gel component, and (ii) a particulate filler component, when applied to the surface or within the gap, to It can be made to be flowable under pressure but shape stable. The gel component can be, for example, a thermoplastic gel or a silicone gel, which can be an organopolysiloxane.

Gels that can be used for the above thermally conductive compounds include not only silicone-based systems, i.e., polysiloxanes such as polyorganosiloxanes, but also polyurethanes, polyureas, fluoropolymers, chlorosulfonates, polybutadienes, Copolymers such as butyl, neoprene, nitrile, polyisoprene, Buna-N, ethylene-propylene (EPR), styrene-isoprene-styrene (SIS), styrene-butadiene-styrene (SBS), ethylene-propylene Copolymers such as diene monomer (EPDM), nitrile butadiene (NBR), styrene-ethylene-butadiene (SEB), and styrene-butadiene (SBR), and blends thereof such as ethylene or propylene-EPDM, EPR, or NBR. As such, it also includes other polymer-based systems, which may be thermoplastic or thermoset.

Polymer gels comprise a continuous polymer phase or network that can be crosslinked chemically, e.g., ionically or covalently, or physically, and oils such as silicon or other oils, plasticizers, unreacted monomers. A fluid expanding polymer system or other fluid expanding agent that swells or otherwise fills the interstices of the mesh may be included. The crosslink density of such networks and the ratio of extenders can be controlled to adjust the elastic modulus, ie softness, and other properties of the gel. Polymer gels can also encompass materials that can be broadly classified as pseudo-gels or gel-like, as having viscoelastic properties similar to gels, e.g. ” having a cross-linked network, but lacking, for example, a fluid expander. Examples of polymers or silicone gels can include soft silicone gels such as "GEL-8100" by NuSil ^™ .

The polymer gel component may be composed of precious and non-precious metals such as nickel, copper, tin, aluminum, and nickel; precious or non-precious metals such as silver-plated copper, nickel, aluminum, tin, or gold; or non-precious and non-precious metals such as silver or non-precious metals such as silver or nickel-plated graphite, glasses, ceramics, plastics, elastomers, or mica, or mixtures thereof. , can be made thermally conductive by filling with a thermally conductive filler.

FIG. 11 is a flowchart of a method 1100 for assembling stator 102 of electric motor 100, according to an exemplary implementation.

Method 1100 may include one or more operations or actions as indicated by one or more of blocks 1102-1110. Although the blocks are shown in sequence, these blocks can also be executed in parallel and/or in a different order than described herein. Also, various blocks may be combined into fewer blocks, split into additional blocks, and/or deleted based on the desired implementation. For this and other processes and methods disclosed herein, it should be understood that the flowcharts illustrate the functions and operations of one possible implementation of the present examples. Alternative implementations are examples of the disclosure in which functions may be performed out of order from those shown or discussed, including substantially concurrently or in reverse order, depending on the functions involved, as will be understood by those of ordinary skill in the art. included within the scope of

At block 1102, method 1100 includes providing a segment (e.g., segment 600) of lamination stack 300 of stator 102 of electric motor 100, wherein segment 600 of lamination stack comprises a slot (e.g., channel 602 or channel 604). ). As used herein, the term "provide" refers to, for example, a segment of lamination stack 300 or other component (eg, slot liner 606), supplying the segment or supplying the segment to a device or work environment. Includes any action to make a segment or any other component available, such as bringing it in for further processing (eg, attaching other components, wrapping wires, etc.).

At block 1104, method 1100 includes providing a slot liner (eg, slot liner 606) formed of an electrically insulating material (eg, insulating paper).

At block 1106, the method 1100 includes applying a thermally conductive gap filler (eg, thermally conductive gap filler 900, 1000) to the outer surface of the slot liner.

At block 1108, the method 1100 places the slot liner with the added thermally conductive gap filler on the segment of the lamination stack such that the thermally conductive gap filler is disposed between the outer surface of the slot liner and the segment. Including inserting into the slot.

At block 1110, method 1100 includes winding a wire (eg, wire 700) around the segment such that a slot liner and a thermally conductive gap filler are disposed between the wire and the segment.

The method 1100 further includes applying a thermally conductive gap filler along one or more of the first side, the second side, or the connection of the slot liner; Applying agent 902, 1002 to the outer surface of cooling tube 802; inserting cooling tube 802 into a semi-circular channel located on the outer circumference of segment 600; attaching end-turn insulators 610, 612 to segment 600; Other steps associated with assembling the stator 102 and electric motor 100 described above may be included, such as.

The above detailed description describes various features and operations of the disclosed system with reference to the accompanying drawings. The example implementations described herein are not meant to be limiting. Particular aspects of the disclosed system can be arranged and combined in a wide variety of different configurations, all of which are contemplated herein.

Moreover, the features illustrated in each of the drawings may be used in combination with each other unless the context dictates otherwise. Accordingly, the drawings should generally be viewed as component aspects of one or more general implementations, with the understanding that not all illustrated features are required for each implementation. be.

Additionally, any recitation of elements, blocks, or steps in the specification or claims is for the purpose of clarity. Therefore, such listing should not be construed as requiring or implying that these elements, blocks, or steps adhere to any particular arrangement, or that these elements, blocks, or steps be performed in any particular order.

Additionally, any device or system may be used or configured to perform the functions illustrated. In some instances, devices and/or system components are configured (using hardware and/or software) such that the components are actually configured and structured (using hardware and/or software) to enable such performance. It can be configured to perform functions. In other examples, devices and/or system components may be adapted, capable, or configured to perform functions, such as when operated in a particular manner. .

The terms "substantially" or "about" do not require that the stated property, parameter, or value be precisely achieved, but rather include, for example, tolerances, measurement errors, and measurement accuracy limits known to those of ordinary skill in the art. , and other factors, may occur in amounts that do not eliminate the effect the feature is intended to provide.

The configurations described herein are for illustrative purposes only. As such, one of ordinary skill in the art may substitute other configurations and other elements (e.g., machines, interfaces, operations, sequences, groupings of operations, etc.), and some elements may vary depending on the desired result. can be omitted entirely according to Moreover, many of the described elements are functional entities that can be implemented as separate or distributed components, or in combination with other components, in any suitable combination and location.

Various aspects and implementations have been disclosed herein, and other aspects and implementations will be apparent to those skilled in the art. The various aspects and implementations disclosed herein are for purposes of illustration and are not intended to be limiting, the true scope being the full scope of equivalents to which such claims are entitled: It is indicated by the following claims. Also, the terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting.

Claims (20)

A stator for an electric motor,
a lamination stack;
slots formed in the lamination stack;
a slot liner disposed in the slot and configured to be electrically insulating;
a thermally conductive gap filler disposed in a gap between the slot liner and the lamination stack;
and windings disposed in the slots. The slot liner comprises a first side, a second side, and a connection configured to connect the first side to the second side, wherein the thermally conductive 2. The stator of claim 1, wherein gap filler is disposed along one or more of the first side, the second side, or the connection. cooling tubes disposed in channels disposed on the outer periphery of the lamination stack;
2. The stator of claim 1, further comprising respective thermally conductive gap fillers disposed in respective gaps between said cooling tubes and said outer peripheral surface of said lamination stack. 4. The stator of claim 3, wherein the channel is semi-circular in shape and longitudinally disposed across the outer peripheral surface of the lamination stack. The lamination stack comprises a plurality of segments arranged adjacent to each other in a radial array, the slots formed in segments of the plurality of segments, the stator further comprising:
a first end-turn insulator disposed at a first end of the segment between the winding and the segment and configured to be electrically insulating;
2. The fixation of claim 1, comprising a second end-turn insulator disposed at a second end of said segment between said winding and said segment and configured to be electrically insulating. Child. 3. The stator of claim 1, wherein the thermally conductive gap filler comprises mineral oil having thermally conductive solid particles suspended therein. 3. The stator of claim 1, wherein the thermally conductive gap filler comprises a mixture of (i) a polymer gel component and (ii) a particulate filler component. An electric motor assembly comprising:
A stator having an open annular space,
a lamination stack comprising a plurality of segments arranged adjacent to each other in a radial array;
a plurality of slots formed between adjacent ones of the plurality of segments of the lamination stack;
each slot liner disposed in the plurality of slots and configured to be electrically insulating;
a thermally conductive gap filler disposed in each gap between the respective slot liner and the plurality of segments of the lamination stack;
a stator comprising windings disposed in the plurality of slots;
a rotor disposed in the open annular space of the stator, comprising:
a steel core;
and a rotor comprising a plurality of magnets arranged in respective radial arrays around said steel core. Each slot liner comprises two separate slot liners, each separate slot liner having a first side, a second side, and connecting said first side to said second side. and the thermally conductive gap filler disposed along one or more of the first side, the second side, or the connection. 9. The assembly of claim 8, wherein: a plurality of cooling tubes, each cooling tube of the plurality of cooling tubes disposed in a channel disposed on an outer peripheral surface of a segment of the plurality of segments of the lamination stack;
9. The assembly of claim 8, further comprising respective thermally conductive gap fillers disposed in respective gaps between said cooling tubes and said outer peripheral surfaces of said segments. 11. The assembly of claim 10, wherein said channel is semi-circular in shape and longitudinally disposed across said outer peripheral surface of said segment. a first end-turn insulator disposed at a first end of each segment of the plurality of segments between the winding and the respective segment and configured to be electrically insulating;
3. A second end-turn insulator disposed at a second end of each said segment between said winding and each said segment and configured to be electrically insulating. 8. Assembly according to 8. 9. The assembly of claim 8, wherein the thermally conductive gap filler comprises mineral oil having thermally conductive solid particles suspended therein. 9. The assembly of Claim 8, wherein the thermally conductive gap filler comprises a mixture of (i) a polymeric gel component and (ii) a particulate filler component. a method,
providing a segment of a lamination stack of an electric motor stator, said segment of said lamination stack comprising a slot;
providing a slot liner formed of an electrically insulating material;
applying a thermally conductive gap filler to the outer surface of the slot liner;
placing the slot liner coated with the thermally conductive gap filler on the segment of the lamination stack such that the thermally conductive gap filler is disposed between the outer surface of the slot liner and the segment; inserting into said slot of
winding a wire around the segment such that the slot liner and the thermally conductive gap filler are disposed between the wire and the segment. The slot liner comprises a first side, a second side, and a connection configured to connect the first side to the second side, wherein the thermally conductive Applying a gap filler to the outer surface of the slot liner fills the thermally conductive gap along one or more of the first side, the second side, or the connection. 16. The method of claim 15, comprising applying a filler. applying respective thermally conductive gap fillers to respective outer surfaces of the cooling tubes;
16. The method of claim 15, further comprising inserting the cooling tube into a channel located on the outer circumference of the segment. 18. The method of claim 17, wherein inserting the cooling tube into the channel comprises inserting the cooling tube into a semi-circular channel. attaching a first end-turn insulator to the first end of the segment such that the wire is electrically insulated from the first end of the segment;
16. The method of claim 15, further comprising attaching a second end-turn insulator to said second end of said segment such that said wire is electrically insulated from said second end of said segment. described method. Applying the thermally conductive gap filler comprises applying (i) a mineral oil having thermally conductive solid particles suspended therein, or (ii) a mixture of a polymer gel component and a particulate filler component. 16. The method of claim 15, comprising:

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