Flat wire centrally-mounted motor for electric motorcycle

Abstract

The utility model discloses a flat wire centrally-mounted motor for an electric motorcycle, which relates to the technical field of motors for electric motorcycles and comprises a stator assembly and a rotor assembly, the stator assembly is composed of a stator core, slot insulation and a flat wire winding, the rotor assembly is composed of a rotor core, magnetic steel, a rotor pressing plate and a motor shaft, and an air gap is arranged between the stator assembly and the rotor assembly. The flat wire centrally-mounted motor for the electric motorcycle adopts a distributed winding, and the flat wire winding in the stator assembly adopts a flat wire enameled wire. According to the flat wire centrally-mounted motor for the electric motorcycle, a distributed winding scheme is adopted, so that the reluctance torque of the motor is improved; the stator adopts a flat wire winding technology, the stator rigidity is improved, and the motor noise is reduced; a direct-current group is reduced, so that the temperature rise of the motor is reduced; 16 grooves with certain shapes are formed in the outer circle of the rotor iron core and are used for reducing the cogging torque of the motor; 16 rotor iron core holes are symmetrically formed in the rotor iron core magnetic steel small V and are used for reducing fifth and seventh harmonics, so that the torque ripple is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of motors for electric motorcycles, in particular to a flat wire mid-mounted motor for electric motorcycles. Background Art

[0002] With the widespread popularity of electric vehicles and the continuous improvement of relevant national regulations, the demand for greater power, more energy saving, higher power density, lighter weight, and quieter operation is becoming increasingly demanding. The flat wire mid-mounted motor for electric motorcycles is a special motor design with the following main features and advantages:

[0003] Flat Wire Design: Flat wire motors use flat copper wire for their stator windings, rather than traditional round copper wire. This design improves the motor's slot fill rate and the number of effective conductors, thereby increasing the motor's efficiency and power density.

[0004] Mid-mounted: A mid-mounted motor is located in the center of the vehicle. This layout optimizes weight distribution, improving handling and stability. It also directly drives the rear wheels, eliminating the need for a drive chain or belt and reducing energy loss.

[0005] Efficient heat dissipation: Flat wire motors are usually equipped with efficient heat dissipation systems, such as water cooling or oil cooling, to ensure that the motor can maintain good temperature control at high power output.

[0006] High torque output: Flat-wire mid-mounted motors are generally able to provide higher torque output due to their design features, which makes electric motorcycles perform well when accelerating and climbing.

[0007] Low maintenance requirements: Since the mid-mounted motor directly drives the rear wheel, the clutch and gearbox of traditional motorcycles are eliminated, reducing maintenance requirements.

[0008] Environmental protection and energy saving: Compared with traditional fuel motorcycles, electric motorcycles have the characteristics of zero emissions and low noise, and are more environmentally friendly and energy-saving.

[0009] At present, the common practice in the industry is to use surface-mount hub motors or round wire concentrated winding motors, which have small reluctance torque, low slot fill rate, low efficiency, rich harmonics, high rotor iron loss, and high magnet and winding temperature. They can no longer meet the needs of future high-performance electric vehicles. Utility Model Content

[0010] In view of this, the purpose of the present utility model is to provide a flat wire mid-mounted motor for electric motorcycles to solve the technical problem that the common practice in the industry is to use surface-mounted hub motors or round wire concentrated winding motors, which have small reluctance torque, low slot fill rate, low efficiency, rich harmonics, large rotor iron loss, and high temperature of magnets and windings, and can no longer meet the needs of future high-performance electric vehicles.

[0011] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0012] A flat wire mid-mounted motor for an electric motorcycle includes a stator assembly consisting of a stator core, slot insulation and flat wire windings, and a rotor assembly consisting of a rotor core, magnetic steel, a rotor pressure plate and a motor shaft, with an air gap provided between the stator assembly and the rotor assembly.

[0013] As a preferred technical solution of the present invention, the flat wire mid-mounted motor for the electric motorcycle adopts a distributed winding, and the flat wire winding in the stator assembly adopts a flat wire enameled wire.

[0014] As a preferred technical solution of the present invention, the magnetic steel is placed in the rotor core in an embedded manner. The magnetic steel adopts a double V-angle structure, and the double V-angle structure consists of a large V-angle and a small V-angle. Sixteen V-shaped rotor core surface modification grooves are opened at the magnetic bridge between the magnetic steel on the surface close to the large V-angle and the outer circle of the rotor core to reduce the cogging torque.

[0015] As a preferred technical solution of the present invention, 16 rotor core holes are symmetrically opened within the small V-angle of the magnetic steel.

[0016] The utility model adopts a distributed winding scheme for the flat-wire mid-mounted motor for electric motorcycles to reduce winding harmonics and improve the motor's magnetic resistance torque; the stator adopts flat-wire winding technology to improve stator stiffness and reduce motor noise; the slot fill rate is increased, the DC group is reduced, and thus the motor temperature rise is reduced; the outer circle of the rotor core is provided with 16 rotor core surface modification grooves of a certain shape to reduce the motor's slot torque; 16 rotor core holes are symmetrically opened in the small V of the rotor core magnetic steel to reduce the 5th and 7th harmonics and thus reduce torque fluctuations.

[0017] Other advantages, objectives, and features of the present invention will be described in detail in the following description and, to some extent, will be apparent to those skilled in the art upon examination and study of the following or may be learned from practice of the present invention. The objectives and other advantages of the present invention may be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the appearance structure of the rotor core of the utility model;

[0019] Figure 2 This is a schematic diagram of the appearance structure of the stator core of the utility model;

[0020] Figure 3 This is a schematic structural diagram of the housing of the utility model;

[0021] Figure 4This is a front cross-sectional structural diagram of the housing of the utility model;

[0022] Figure 5 This is a schematic diagram of the structure of the magnetic steel of the utility model adopting a double V-angle structure;

[0023] Figure 6 This is a schematic structural diagram of the flat wire winding of the utility model;

[0024] In the figure: output shaft 1, front cover 2, housing 3, stator assembly 4, rear cover 5, rotor assembly 6, stator core 7, slot insulation 8, flat wire winding 9, motor shaft 10, rotor pressure plate 11, magnet 12, rotor core 13, rotor core surface modification groove 14, rotor core hole 15, cooling fin 16. DETAILED DESCRIPTION

[0025] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0028] In the above description of the present invention, it should be noted that the terms "one side" and "the other side" and the like indicate positions or locations based on the positions or locations shown in the accompanying drawings, or the positions or locations in which the product of the present invention is typically placed when in use. These terms are intended solely to facilitate the description of the present invention and simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" and the like are used solely for distinction and should not be construed as indicating or implying relative importance.

[0029] Furthermore, the term "identical" and similar terms do not necessarily require that the components be absolutely identical; slight variations are permitted. The term "perpendicular" simply refers to the positional relationship between components being more perpendicular than "parallel," not that the structure must be perfectly vertical; rather, it can be slightly tilted. Example 1

[0030] See also Figure 1-6 The present invention provides a technical solution for a mid-mounted flat-wire motor for an electric motorcycle, comprising a stator assembly consisting of a stator core 7, slot insulation 8, and flat-wire windings 9; and a rotor assembly consisting of a rotor core 13, magnets 12, a rotor pressure plate 11, and a motor shaft 10. An air gap is provided between the stator and rotor assemblies. The air gap between the stator and rotor cores is 0.4 to 1 mm; the magnet thickness is 2 to 5 mm.

[0031] In this embodiment, the outer diameter of the stator core is between 90 mm and 160 mm; and the core stack height is between 25 mm and 120 mm.

[0032] In this embodiment, the circumferential gap between the stator core and the winding slot is 0.2 to 0.3 mm, that is, the slot width minus the slot insulation thickness*2 minus the flat wire width.

[0033] In this embodiment, the total radial gap between the stator core and the winding slot is (radial dimension 1-slot insulation thickness*3-flat wire thickness*number of flat wire layers) 0.6 to 0.7 mm.

[0034] The flat wire mid-mounted motor for electric motorcycles adopts a distributed winding scheme to reduce winding harmonics and improve the motor's magnetic resistance torque; the stator adopts flat wire winding technology to improve stator stiffness and reduce motor noise; the slot fill rate is increased, the DC group is reduced, and thus the motor temperature rise is reduced; the outer circle of the rotor core is opened with 16 rotor core surface modification slots 14 of a certain shape to reduce the motor's slot torque; 16 rotor core holes are symmetrically opened in the small V of the rotor core magnet to reduce the 5th and 7th harmonics, thereby reducing torque fluctuations.

[0035] The flat wire mid-mounted motor for the electric motorcycle adopts a distributed winding, and the flat wire winding 9 in the stator assembly adopts a flat wire enameled wire.

[0036] The magnets 12 are embedded within the rotor core 13 and feature a double V-angle structure. The rotor magnets employ a double V structure, with the large V-angle (angle 1) ranging from 80° to 120° and the small V-angle (angle 2) ranging from 100° to 170°. The double V-angle structure comprises a large V-angle and a small V-angle. Sixteen V-shaped rotor core surface modification slots 14 are located on the surface of the rotor core 13, where the magnets near the large V-angle meet the outer magnetic bridge, to reduce cogging torque. The angle 3 of the rotor core surface modification slots 14 ranges from 15° to 32°.

[0037] Sixteen rotor core holes are symmetrically formed within the small V-shaped angle of the magnetic steel 12. Symmetrical rotor core holes 15 are formed within the small V-shaped angle of the rotor magnetic steel. The hole center angle 4 is between 3° and 10°, and the hole radius is between 0.5 and 2 mm. The minimum distance between the circular edge and the magnetic steel slot and the outer circle of the rotor core is no less than 0.2 mm. Example 2

[0038] See also Figure 1-6 , which is another technical solution provided by the present utility model. This embodiment is similar to the above-mentioned embodiment 1, and the similarities are not elaborated in this embodiment. The specific differences are:

[0039] A flat wire mid-mounted motor for an electric motorcycle includes a stator assembly 4 consisting of a stator core and windings; and a rotor assembly 6 consisting of a rotor core, permanent magnets, a rotating shaft, and a rotor pressure plate. An air gap is provided between the stator assembly and the rotor assembly, and the stator assembly is connected to the rotor assembly 6 via front / rear bearings, a front end cover 2, and a rear end cover 5.

[0040] A plurality of heat dissipation fins 16 are provided on the top surface of the housing 3. Arranging a plurality of heat dissipation fins 16 on the surface can achieve lightweight and help heat dissipation.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model and are not limiting. Although the utility model is described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. Flat wire mid-mounted motor for electric motorcycle, characterized in that: The invention comprises a stator assembly consisting of a stator core (7), slot insulation (8) and a flat wire winding (9), and a rotor assembly consisting of a rotor core (13), magnetic steel (12), a rotor pressure plate (11) and a motor shaft (10), wherein an air gap is provided between the stator assembly and the rotor assembly.

2. The flat wire mid-mounted motor for an electric motorcycle according to claim 1, characterized in that: The flat wire mid-mounted motor for the electric motorcycle adopts a distributed winding, and the flat wire winding (9) in the stator assembly adopts a flat wire enameled wire.

3. The flat wire mid-mounted motor for an electric motorcycle according to claim 1, characterized in that: The magnetic steel (12) is embedded in the rotor core (13), and the magnetic steel adopts a double V-angle structure, wherein the double V-angle structure comprises a large V-angle and a small V-angle. Sixteen V-shaped rotor core surface shaping grooves (14) are provided at the magnetic bridge between the magnetic steel on the surface close to the large V-angle and the outer circle of the rotor core (13) to reduce the cogging torque.

4. The flat wire mid-mounted motor for an electric motorcycle according to claim 1, characterized in that: Sixteen rotor core holes (15) are symmetrically formed within the small V-angle of the magnetic steel (12).

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