In-wheel generator

Abstract

The invention discloses an in-wheel generator for a vehicle. The in-wheel generator includes: a stator configured to be coupled to a non-rotating main shaft of a vehicle; and a rotor configured to be indirectly coupled to a rotating hub of the vehicle. The in-wheel generator is configured to be disposed outside the rotating hub. The invention further discloses a vehicle comprising the in-wheel generator and an auxiliary unit system for a trailer, wherein the auxiliary unit system is used for supplying power to the auxiliary unit through the in-wheel generator.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to UK Patent Application No. 2210088.7 filed on July 8, 2022, and claims priority to UK Patent Application No. 2209889.1 filed on July 5, 2022, which are hereby incorporated by reference in their entirety. Technical Field

[0002] The present disclosure relates to an in-wheel generator. In particular, the in-wheel generator is used to supply energy to an auxiliary system of a vehicle (e.g., a truck or trailer), in particular to supply energy to or supplement energy supply to a battery that powers an auxiliary unit (e.g., a refrigeration unit). The present application also discloses an in-wheel generator system and a vehicle including the in-wheel generator. Background Art

[0003] Electric machines, including motors and generators, have a wide range of applications. However, concerns about our reliance on fossil fuel-based internal combustion engines and the pollution they cause are increasing political and commercial pressure to expand the use of electric machines into new applications and to extend their use in existing applications. Electric machines are increasingly used in transportation, such as electric cars, motorcycles, ships, and aircraft. They are also used in energy production, such as generators in wind turbines.

[0004] Another possible application of the generator is to supply energy to auxiliary systems of the vehicle.The generator may be provided as an in-wheel generator configured to generate electricity while the vehicle is moving.

[0005] Auxiliary systems for trailers may be a suitable application for such in-wheel generators. However, since such trucks and trailers typically have a two-wheel arrangement, their wheels differ significantly from those of electric cars and motorcycles. Therefore, in-wheel generators for such vehicles typically require significant modifications to the standard wheels used for such trucks.

[0006] However, any modification to a standard wheel hub may affect whether integration of an in-wheel generator is economical. Therefore, the inventors have recognized a need for an in-wheel generator that can be integrated into a vehicle with minimal or no structural modifications to a standard wheel hub. Furthermore, the inventors have recognized a need for a retrofittable in-wheel generator. Summary of the invention

[0007] The embodiments described herein provide an in-wheel generator for a vehicle, an in-wheel generator assembly for a vehicle, a vehicle including an in-wheel generator assembly, and an auxiliary unit system for a trailer, as defined in the accompanying independent claims, to which reference should now be made. Preferred or advantageous features of the disclosure are listed in the dependent claims.

[0008] According to a first aspect of the present disclosure, there is provided an in-wheel generator for a vehicle, comprising: a stator configured to be coupled to a non-rotating main shaft of the vehicle; a rotor configured to be indirectly coupled to a rotating wheel hub of the vehicle; and a gearbox having an input end that can be coupled to the rotating wheel hub and an output end that is coupled to the rotor. The in-wheel generator is configured to be disposed outside the rotating wheel hub.

[0009] Advantageously, an in-wheel generator is provided on the outside of a rotating wheel hub, and the rotor of the generator is coupled to the wheel hub via a gearbox, so that the in-wheel generator can be mounted to a standard wheel hub of a vehicle (e.g. a trailer). Thus, the in-wheel generator can be retrofitted to a vehicle without any modification or major modification to the vehicle.

[0010] As used herein, the terms "outboard" and "outboardly" refer to an orientation relative to a vehicle to which an in-wheel generator may be coupled in use. In particular, outboard may refer to a location further from the vehicle. The term "roadside" may be used instead of "outboard".

[0011] Although the term "gearbox" is used throughout, it should be understood that any suitable type of transmission may be used. In particular, any suitable single ratio transmission may be used.

[0012] Optionally, the in-wheel generator further comprises a housing configured to be directly coupled to the rotating wheel hub and directly coupled to the input of the gearbox. Providing such a housing advantageously mechanically couples the rotating wheel hub and thus the wheel of the vehicle to the rotor of the generator and prevents water, dust and other debris from entering the generator.

[0013] Preferably, the gearbox is a planetary gearbox with a sun gear coupled to the rotor, planet gears rotatably coupled to the stator housing, and a ring gear coupled to the housing. Advantageously, the use of a planetary gearbox reduces the overall volume required for the in-wheel generator while still being able to achieve a suitable gear ratio between the input and output ends.

[0014] Although the term "planetary gearbox" is used, it will be appreciated that any suitable planetary transmission arrangement may be used.

[0015] The sun gear and the planetary gears are preferably rotatably coupled to the outer surface of the stator housing via respective shafts. Each gear is mounted to each respective shaft via a bearing. The stator housing and the shafts may be configured to be in thermal communication with the housing, preferably in thermal communication with the third housing portion.

[0016] Optionally, the gearbox is mechanically sealed. The gearbox can be mechanically sealed from the bearings of the rotor and stator and / or the wheel hub. By mechanically sealing the gearbox from the bearings of the rotor and stator and / or the wheel hub, the gearbox can be lubricated separately, thereby enabling the use of separate lubricants for the gearbox and the wheel hub bearings.

[0017] Optionally, the stator housing comprises a first coupling portion configured to engage a corresponding coupling portion of a non-rotating main shaft of the vehicle. The first coupling portion may comprise at least one protrusion configured to radially engage with at least one corresponding recess on the non-rotating main shaft of the vehicle. In such an embodiment, the corresponding coupling portion comprises at least one corresponding recess. The protrusion or key is preferably provided on a shaft portion of the stator housing that is configured to engage with an end of the non-rotating main shaft of the vehicle, preferably in an end of the non-rotating main shaft of the vehicle. The recess or keyway may be provided on the inner wall of the main shaft.

[0018] Alternatively, the stator housing may be configured to be coupled to a non-rotating main shaft of the vehicle using a spline coupling.In such an embodiment, the first coupling portion may include a plurality of splines.

[0019] Optionally, the first coupling portion comprises threads configured to engage corresponding threads of the non-rotating main shaft.Alternatively, the first coupling portion may be configured to engage a corresponding coupling portion of the non-rotating main shaft of the vehicle using a pin and hole.

[0020] The coupling between the first coupling part and the corresponding coupling part is particularly configured to resist torque from the stator. Therefore, providing such a coupling meets the requirements of rotational reaction torque. The coupling is also configured to radially center the stator with the non-rotating main shaft.

[0021] When provided, the housing preferably includes a first housing portion and a second housing portion, the first housing portion being configured to be coupled to the rotating hub, and the second housing portion being configured to be coupled to the first housing portion and to the input end of the gearbox. The housing is configured to surround the stator. As will be appreciated, in the case of providing a stator housing, the housing is configured to surround the stator housing. Optionally, the second housing portion is configured to surround the gearbox. In this embodiment, the housing may also include a third housing portion, which is configured to cover the outer end of the housing to surround the gearbox. The first housing portion may be configured as an adapter plate and may therefore be provided in a variety of configurations to enable coupling to the corresponding configuration of the rotating hub without modifying any other components. The in-wheel generator may also include a gasket configured to provide a seal between the first housing portion and the rotating hub.

[0022] It is worth noting that in the axial direction the generator is fixed by the first housing part and its connection towards the rotating hub, wherein the length of the main shaft relative to the position of the hub on the main shaft is chosen to ensure axial alignment.

[0023] Optionally, the gearbox is arranged outside the stator and rotor. Advantageously, providing the gearbox in this arrangement makes maintenance easier and eliminates the need to remove the in-wheel generator from the vehicle during maintenance.

[0024] Preferably, the gearbox is configured to increase the output speed relative to the input speed. The gear ratio of the gearbox can be between about 3:1 and about 10:1, preferably between about 5:1 and about 7:1. In a specific embodiment, the gear ratio can be about 5.75:1. Advantageously, this gearbox ratio enables the generator to run at an efficient speed within the expected input (i.e., wheel) speed range. In one example, the maximum input speed is about 630rpm, thus resulting in a maximum output speed of about 3625rpm. When the in-wheel generator is used with a standard trailer wheel, the gearbox can be configured to have a maximum input torque of about 72Nm. Therefore, in this specific embodiment, the maximum expected torque acting on the rotor is about 12.5Nm.

[0025] Optionally, the in-wheel generator further comprises at least one vent configured to vent to the atmosphere. The vent may be provided with a breathable membrane configured to substantially prevent the ingress of water and / or dust and debris. Advantageously, providing the vent may prevent a pressure differential between the internal pressure of the in-wheel generator and the external pressure, which may cause damage to components of the in-wheel generator.

[0026] Optionally, the in-wheel generator has an outer diameter of less than 220 mm, preferably less than or equal to 200 mm, and in one embodiment, less than or equal to 180 mm. By providing the generator with such a maximum diameter, it can be used with a substantially standard (i.e., unmodified) hub and wheel arrangement. In this way, the ability to retrofit and maintain the wheel is improved.

[0027] The in-wheel generator may comprise at least one temperature sensor for measuring the temperature of a temperature-sensitive component of the in-wheel generator. In this way, the in-wheel generator may be protected from damage caused by overheating.

[0028] The in-wheel generator may comprise at least one rotational position sensor. Such a position sensor may allow improved control of the generator.

[0029] According to a second aspect of the present disclosure, there is provided an in-wheel generator assembly comprising: a generator as described herein; a central rotating hub; and a main shaft configured to be mounted to a vehicle. The stator is coupled to the main shaft, and the rotor is indirectly coupled to the central hub via a gearbox.

[0030] Advantageously, providing such an assembly enables the in-wheel generator to be mounted to a standard wheel hub of a vehicle, such as a trailer or truck. Thus, the in-wheel generator can be retrofitted to a vehicle without any modification or major modification to the vehicle. In particular, arranging the in-wheel generator outside of a rotating wheel hub enables the wheel to be mounted to or removed from the wheel hub without removing the in-wheel generator.

[0031] Optionally, the main shaft is a full main shaft or axle, which is configured to be mounted directly to the vehicle, preferably configured to be mounted indirectly to the vehicle through a suspension device. A full main shaft can be configured to mount an in-wheel generator at both ends thereof. Alternatively, the main shaft is a "half main shaft", which is configured to be mounted directly to the vehicle, preferably configured to be mounted indirectly to the vehicle through a suspension device.

[0032] For example, the trailer may include two main shafts carrying four in-wheel generators. In another example, the trailer may include three main shafts carrying six in-wheel generators.

[0033] Optionally, the main shaft is hollow and the assembly further comprises wires passing through the hollow main shaft or being configured to be connected to wires passing through the hollow main shaft. Preferably, the outwardly facing end of the hollow main shaft is configured to receive and couple with the stator. The wires may include at least one of: at least one cable for conducting power from the generator, preferably three cables for a three-phase AC connection; at least one temperature sensor and / or wires for at least one temperature sensor; wires for a generator rotational position sensor; wires for a high voltage interlock loop (HVIL); and a ground connection, such as a ground wire or cable sheath.

[0034] Optionally, when including wires for a high voltage interlock loop (HVIL), the in-wheel generator assembly further comprises an interlock switch configured to be electrically opened when the housing is at least partially removed. Providing such an interlock switch enables the battery to be automatically disconnected from the inverter of the generator when the housing is opened, for example for maintenance purposes. This prevents the operator from being exposed to the risk of high voltage.

[0035] Optionally, the assembly further comprises, or is configured to be connected to, an automatic tire inflation system passing through the hollow spindle.

[0036] The in-wheel generator is preferably arranged for sensorless control, but may include a rotational position sensor as described above.

[0037] The wheel hub can be configured to receive at least one standard wheel, preferably two standard wheels. The in-wheel generator is particularly suitable for use on a truck or trailer to power auxiliary equipment (such as a refrigeration unit), and enabling one or more standard wheels in this way reduces costs and improves availability. In order to enable the use of one or more standard wheels, at least one standard wheel is preferably connected to the wheel hub by a plurality of fasteners having a pitch diameter that is larger than the diameter of the in-wheel generator. In this embodiment, it is particularly preferred that each fastener can be accessed without removing the in-wheel generator. Advantageously, this diameter arrangement of the pitch diameter and the in-wheel generator, i.e., the relative size of the generator with respect to the wheel size allows the pitch diameter to be larger than the motor, can facilitate easier attachment of the wheel to the central hub.

[0038] In fact, such an in-wheel generator can allow the largest possible generator diameter while still providing a standardized way of mounting the wheel (rim) to a standard hub. Since the volume of the generator is related to the power output, allowing the largest possible generator diameter can enable the in-wheel generator to provide the maximum possible power.

[0039] The inner diameter of the rim opening can be larger than the diameter of the generator. In fact, since the in-wheel generator can be accommodated within the inner diameter of the rim, the rim can be easily removed.

[0040] Optionally, the in-wheel generator assembly further comprises an electrical connector configured to be mounted to the vehicle chassis and electrically connect the in-wheel generator to a system on the vehicle. Preferably, the electrical connector is a quick connect connector comprising a plurality of spring loaded connectors, one for each wire from the in-wheel generator. Such a connector advantageously enables the in-wheel generator assembly to be more easily retrofitted to the vehicle and / or easy to assemble.

[0041] Optionally, an electrical connector is fixed to the in-wheel generator assembly. Such an electrical connector may be referred to as a chassis mounted connector. The chassis mounted connector may be connected to a wiring harness inside the main shaft, which consists of a matching counter connector.

[0042] Alternatively or additionally, the main shaft and in-wheel generator assembly each include a fixed connector arrangement including spring-loaded contacts configured to automatically connect when the assembly is installed.

[0043] Optionally, the in-wheel generator assembly also includes a semi-fluid grease or other such lubricant to lubricate the rotating hub and ease the sealing interface.

[0044] The in-wheel generator and the in-wheel generator assembly may be particularly suitable for use in trailers. The in-wheel generator and the in-wheel generator assembly may also be suitable for use in caravans, motorhomes, trucks and vans.

[0045] According to a third aspect of the present disclosure, there is provided a vehicle comprising at least one in-wheel generator assembly as described herein.

[0046] The vehicle may be one of: a trailer; a caravan; a motorhome; a truck; and a van. In particular, the vehicle may be a US Class 4-8 truck of various configurations, such as a US Class 6 / 7 truck of 6x4 configuration, or a US Class 8 truck of 6x4 configuration, or a trailer suitable for use with such a vehicle.

[0047] When the vehicle is a trailer, it may be one of: a semi-trailer; a full-trailer; a box trailer; a curtain-side trailer; a flatbed trailer; a low-bed trailer; a skeleton trailer; a mobile floor trailer; a refrigerated trailer; or any suitable combination thereof.

[0048] According to a fourth aspect of the present disclosure, there is provided an auxiliary unit system for a trailer, comprising: at least one in-wheel generator assembly as described herein; and an auxiliary unit. The in-wheel generator is configured to supply power to the auxiliary unit on the trailer.

[0049] The auxiliary unit system for the trailer may further include an electric energy storage device, the auxiliary unit being configured to be electrically coupled to the electric energy storage device. The in-wheel generator is configured to be electrically coupled to the electric energy storage device, so that when in use, the electric energy generated by the in-wheel generator is stored in the electric energy storage device. Preferably, the auxiliary unit system further includes an inverter electrically coupled between the in-wheel generator and the electric energy storage device.

[0050] The in-wheel generator is preferably a three-phase AC generator, and the inverter is configured to invert the three-phase AC voltage of the in-wheel generator into a DC voltage, thereby ensuring that an appropriate amount of power is delivered to the electrical energy storage device.

[0051] In one embodiment, the auxiliary unit is a refrigeration unit, but as will be appreciated, any suitable auxiliary unit provided on a trailer or other vehicle may be powered by the in-wheel generators described herein.

[0052] The electrical energy storage device may be a battery, preferably a battery comprising a plurality of electrochemical cells. Alternatively or additionally, the electrical energy storage device may be a capacitor or a supercapacitor.

[0053] It should be understood that the features described in relation to one aspect of the present disclosure may also be applied to all other aspects of the present disclosure. The features described in relation to the first aspect of the present disclosure may also be applied to the second aspect of the present disclosure, and vice versa. For example, the features of the drive assembly described in relation to the first aspect may be applied to the vehicle of the second aspect after appropriate modification.

[0054] It will also be appreciated that specific combinations of the various features described and defined in any aspect of the invention may be implemented and / or provided and / or used independently. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Specific embodiments of the present disclosure will now be described with reference to the accompanying drawings, in which:

[0056] Figure 1 shows a side view of the in-wheel generator assembly;

[0057] Figure 2 Shows Figure 1 A cross-sectional side view of an in-wheel generator assembly;

[0058] Figure 3 Shows Figure 1 and Figure 2 A cross-sectional perspective view of an in-wheel generator assembly including a rim, tire and brake assembly of a vehicle;

[0059] Figure 4 shows a perspective view of an in-wheel generator and a brake disc according to the present disclosure;

[0060] FIG5( a ) shows a cross-sectional side view of an in-wheel generator according to the present disclosure;

[0061] FIG5( b ) shows an enlarged cross-sectional side view of a portion of an in-wheel generator assembly according to the present disclosure, including the generator shown in FIG5( a );

[0062] Figure 6 shows an enlarged cross-sectional side view of an in-wheel generator according to the present disclosure coupled to a wheel hub and a brake disc of a vehicle;

[0063] Figure 7 a cross-sectional perspective view showing a gearbox of an in-wheel generator according to the present disclosure; and

[0064] Figure 8 A system diagram showing an in-wheel generator system connected to an auxiliary machine system. DETAILED DESCRIPTION

[0065] Figure 1 and Figure 2 An example in-wheel generator assembly 100 is shown coupled to a rim assembly 101 including a main shaft 102 through which electrical wires (not shown) extend. The rim assembly 101 includes an outboard or roadside rim 101a and an inboard or vehicle side rim 101b.

[0066] The wheel rim is coupled to the wheel hub 200, as will be described in more detail below. The brake disc 202 is attached to the wheel hub 200, which forms part of the brake assembly 304, as shown in FIG. Figure 3 shown.

[0067] The spindle 102 is coupled to the vehicle via a conventional suspension system so as to allow only limited movement relative to the vehicle when the vehicle is moving, while the hub 200 is configured to rotate with the wheel. A full spindle or axle is shown here, but it should be understood that a half spindle may be used with an independent suspension arrangement.

[0068] The in-wheel generator 203 is coupled to the wheel hub 200 on the outer side or road side of the wheel hub 200 and is surrounded by the outer wheel rim 101a. The in-wheel generator 203 includes a rotor 204 (shown in detail in Figure 5(a)), a stator 205 (also shown in detail in Figure 5(a)), and a planetary gearbox 206 located on the outer side or road side of the rotor 204 and the stator 205. The planetary gearbox 206 is described in more detail below. In this example, the generator is of IPM (embedded permanent magnet) type and includes a 12-slot 8-pole electromagnetic device. However, of course, it should be understood that any suitable type of generator can be used. The generator in this example is configured to have a maximum output power of 5kW and a continuous output power of 3.5kW.

[0069] like Figure 3 As shown, wheel rims 101a, 101b carry respective tires 300a, 300b for engaging a road surface.

[0070] In addition, if Figure 3 As shown, a cable 302 is arranged inside the main shaft 102. The cable 302 includes wires for transmitting the electricity generated by the generator to the system on the vehicle. The main shaft 102 extends through the central cavity of the hub 200, thereby allowing the cable 302 to pass from the road side of the hub 200 to the vehicle side of the hub 200.

[0071] Hub 200 is a standardized hub for truck trailers, particularly for trailers with auxiliary equipment systems (such as trailer refrigeration units). Cables 302 allow power (for in-wheel generators 203, for temperature and position sensors, and for HVIL and ground) to flow from the vehicle side of hub 200 to the road side of hub 200, and vice versa.

[0072] A cover 306 is provided at the outer or roadside end of the gearbox 206. The cover 306 is removable to allow access to the interior of the gearbox 206 and / or the interior of the generator 203. Figure 4 As shown in detail, cover 306 is removably attached to gearbox 206 via fasteners 400. Cover 306 also includes holes 401 that can improve heat dissipation.

[0073] like Figure 4As shown, the in-wheel generator 203 includes a housing including a first housing portion 402 coupled to the rotating hub 200, and a second housing portion 404 coupled to the first housing portion 402 and the gearbox 206. Another housing portion 405 and a cover 306 coupled to the second housing portion 404 on the outside form a third housing portion that completes the housing of the generator.

[0074] Fig. 5(a) shows a cross-sectional view of the in-wheel generator 203 as described above. As described herein, the in-wheel generator 203 includes a housing 500. The housing 500 includes a first housing portion 402, a second housing portion 404, and a third (cover) portion 306, the first housing portion 402 being configured to be directly coupled to the outer surface of the rotating hub 200 via fasteners, and the second housing portion 404 being configured to be coupled to the first housing portion 402 via fasteners.

[0075] The first housing portion 402 may be referred to as an adapter plate because the first housing portion 402 may be adapted to a standard wheel hub 200 to which the in-wheel generator 203 is coupled. A gasket (not shown) exists between the first housing portion 402 and the wheel hub 200 for sealing the coupling.

[0076] The housing 500 is configured to house the stator 205, which is formed by a stator assembly 502 and a stator housing 506, the stator assembly 502 being composed of an arrangement of conductive coils 504. The stator housing 506 includes a portion 508 configured to be coupled to the wayside end of the main shaft 102. The wayside end of the main shaft 102 includes a keyway (not shown) for radially securing the stator 205 to the main shaft 102. The portion 508 includes a key configured to engage with the keyway.

[0077] The rotor 204 having permanent magnets is disposed within the stator 205. The rotor 204 is supported by a rotor shaft 508, which is supported by an inner bearing 510 and an outer bearing 512, both of which are mounted in a stator housing 506.

[0078] As shown, an annular flange 514 is provided that partially surrounds one end of the stator housing 506. The annular flange 514 enables a seal 516 to be provided to seal the gap between the outer radial surface of the stator housing 506 and the annular protrusion 514. Thus, the annular flange 514 and the seal 516 act to seal and mechanically separate the gearbox 206 from the stator 205 and the rotor 204. A similar seal 518 is provided at the third (cover) portion 306 to isolate the gearbox 206 from the external environment.

[0079] The planetary gearbox 206 includes an input ring gear 520 (also shown in FIG. Figure 7) and an output sun gear 522, the input ring gear 520 is coupled to the rotating hub 200 through the second housing portion 404 (and the first housing portion 402), and the output sun gear 522 is coupled to the rotor shaft 508. The input ring gear 520 is coupled to the output sun gear 522 through three planetary gears 524 (only two are shown). The planetary gears 524 are mounted on the shaft through bearings (such as Figure 7 As shown), the shaft is integral with the outer surface of the stator housing 506.

[0080] Now looking at Figure 5(b), it can be seen that the in-wheel generator 203 is coupled to the rotating wheel hub, and the wheel rim is in turn coupled to the wheel hub. As shown, the main shaft 102 is disposed within an inner thrust bearing 526 of the wheel hub.

[0081] The rims 101a, 101b are attached to the hub 200 by fasteners 406 disposed at a pitch diameter around the hub 200. The relative diameters of the in-wheel generator 203 and the pitch diameter of the fasteners 406 are selected so that the fasteners 406 can be fastened to attach the rim to the hub 200 from the roadside.

[0082] Although the outer diameter of the stator housing in this embodiment is about 180 mm, the stator housing can have a larger outer diameter. The maximum outer diameter is less than 220 mm because the limiting factor (for example, for trailers) is that the inner rim diameter of the wheel rims 101a, 101b can be about 220 mm.

[0083] Watch now Figure 7 , a detailed view of a planetary gearbox. The rotation of the second housing portion 404 is transmitted to the gearbox 206 via the ring gear 520 of the gearbox 206. The ring gear 520 is coupled to three planetary gears 524a, 524b, 524c, which in turn are coupled to a sun gear 522. Each planetary gear 524a, 524b, 524c is rotatably mounted to the stator housing via respective shafts 700a, 702a, and 704a. The shaft of the sun gear 522 is coupled to the rotor shaft 508, thereby coupling the gearbox 206 to the rotor 204.

[0084] like Figure 7 As shown, block 706 is provided to thermally connect the stator to the housing cover portion 306, thereby improving the ability of the generator to dissipate heat to the environment. The configuration of block 706 also improves lubrication of the planetary gears 524a, 524b, 524c.

[0085] The planetary gearbox 206 is arranged to increase the rotational output speed of the gearbox 206 relative to the rotational input speed. The rotational output speed of the gearbox 206 may be increased relative to the rotational input speed by a ratio of approximately 5.75:1.

[0086] Figure 8 A system diagram of a vehicle 800 is shown, including four in-wheel generators 802a-d, each pair of in-wheel generators 802a-d is connected to respective inverters 804a, b by wires, the wires respectively including three phase cables, a ground cable, a temperature sensor cable and a high voltage interlock loop (HVIL) cable.

[0087] The vehicle 800 comprises an electrical energy storage device, namely a battery 804 comprising electrochemical cells, to which an inverter is connected. A control unit 806 controls the battery and the inverters 804a, b. A trailer refrigeration unit (TRU) 808 is electrically connected to the battery 804 via another inverter 810.

[0088] The TRU 808 includes a switch box 812, a compressor 814, and a refrigeration circuit 816. The switch box is also connected to an air management system 818 of the TRU 808.

[0089] Although the vehicle 800 in this example is a refrigerated trailer with TRU 808, it will be apparent to those skilled in the art that the in-wheel generator and in-wheel generator assembly according to the present disclosure can be used to power any auxiliary component or system of a vehicle or trailer. In fact, the vehicle may not be a trailer, but may be, for example, a truck, and the number of inverters and in-wheel generators may vary depending on the application.

Claims

1. An in-wheel generator for a vehicle, comprising: a stator configured to be coupled to a non-rotating main shaft of a vehicle; a rotor configured to be indirectly coupled to a rotating hub of the vehicle; and The in-wheel generator is configured to be disposed outside the rotating hub. 2 . The in-wheel generator of claim 1 , further comprising a gearbox having an input end coupleable to the rotating hub and an output end coupled to the rotor.

3. The in-wheel generator of claim 2, further comprising a housing configured to be directly coupled to the rotating hub and directly coupled to an input end of the gearbox.

4. The in-wheel generator according to claim 3, wherein: The gearbox is a planetary gearbox, a sun gear is coupled to the rotor, planet gears are rotatably coupled to a stator housing, and a ring gear is coupled to the housing.

5. The in-wheel generator according to claim 4, wherein: The stator housing includes a first coupling portion configured to engage a corresponding coupling portion of a non-rotating main shaft of a vehicle.

6. The in-wheel generator according to claim 5, wherein: The first coupling portion includes at least one protrusion configured to radially engage at least one corresponding recess on a non-rotating primary shaft of the vehicle.

7. The in-wheel generator according to any one of claims 3 to 6, wherein: The housing includes a first housing portion configured to be coupled to the rotating hub and a second housing portion configured to be coupled to the first housing portion and to an input end of the gearbox, wherein the housing is configured to surround the stator.

8. The in-wheel generator according to any one of claims 2 to 7, wherein: The gearbox is arranged outside the stator and the rotor.

9. The in-wheel generator according to any one of claims 2 to 8, wherein: The gearbox is configured to increase an output speed relative to an input speed.

10. The in-wheel generator according to claim 9, wherein: The gear ratio of the gearbox is between about 3:1 and about 10:1, preferably between about 5:1 and about 7:

1.

11. The in-wheel generator according to any one of claims 2 to 10, wherein: The gearbox is separated from the rotor and stator by mechanical seals.

12. The in-wheel generator according to any one of the preceding claims, further comprising at least one vent configured to vent to the atmosphere.

13. In-wheel generator according to any of the preceding claims, having an outer diameter less than 220 mm, preferably less than or equal to 200 mm.

14. An in-wheel generator assembly, comprising: A generator according to any one of the preceding claims; Center rotating hub; and a spindle configured to be mounted to a vehicle, Therein, the stator is coupled to the main shaft and the rotor is connected to the central hub.

15. The in-wheel generator assembly according to claim 14, wherein: The spindle is hollow, and the assembly further comprises, or is configured to be connected to, electrical wires passing through the hollow spindle.

16. The in-wheel generator assembly according to claim 15, wherein: The outwardly facing end of the hollow spindle is configured to receive and couple with the stator.

17. The in-wheel generator assembly according to claim 15 or 16, wherein: The electrical wire comprises at least one of the following: at least one cable for conducting power from said generator; at least one temperature sensor and / or wiring for at least one temperature sensor; and wires for the motor's rotational position sensor; and Wires for high voltage interlock circuits; and A ground connection, such as a ground wire or cable sheath.

18. The in-wheel generator assembly of claim 17, when including electrical wiring for a high voltage interlock circuit, further comprising an interlock switch configured to open when the housing is at least partially removed.

19. The in-wheel generator assembly according to any one of claims 14 to 18, wherein: The hub is configured to receive at least one standard wheel, preferably two standard wheels.

20. The in-wheel generator assembly according to claim 19, wherein: The at least one standard wheel is coupled to the hub via a plurality of fasteners having a pitch diameter that is greater than a diameter of the in-wheel generator.

21. The in-wheel generator assembly according to claim 20, wherein: Each fastener is accessible without removing the in-wheel generator.

22. The in-wheel generator assembly of any one of claims 14 to 21, further comprising an electrical connector configured to be mounted to a vehicle chassis and configured to electrically connect the in-wheel generator to a system on the vehicle.

23. A vehicle comprising at least one in-wheel generator assembly according to any one of claims 14 to 22.

24. An auxiliary unit system for a trailer, comprising: at least one in-wheel generator assembly according to any one of claims 14 to 22; and Auxiliary units, wherein the in-wheel generator is configured to supply power to the auxiliary units on the trailer.

25. The auxiliary unit system for a trailer according to claim 24, further comprising an electric energy storage device, the auxiliary unit being configured to be electrically coupled to the electric energy storage device, wherein: The in-wheel generator is configured to be electrically coupled to the electrical energy storage device such that, in use, electrical energy generated by the in-wheel generator is stored in the electrical energy storage device.

26. The auxiliary unit system for a trailer according to claim 25, further comprising an inverter electrically coupled between the in-wheel generator and the electric energy storage device.

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