Dual-motor driving system and vehicle

Abstract

The utility model provides a dual-motor driving system and a vehicle, and belongs to the technical field of motor driving, the dual-motor driving system comprises a motor shell and two driving motors, and the two driving motors are arranged in the motor shell; the driving motor comprises motor shafts, a motor rotor and a motor stator, the motor rotor is installed on the motor shafts, the periphery of the motor rotor is sleeved with the motor stator, and the two motor shafts are coaxially arranged and jointly connected with the speed reducer; the inner diameter of one motor stator is larger than the outer diameter of the other motor stator, and the two motor stators are mutually and partially sleeved in the axial direction so as to reduce the length of the motor shaft. According to the double-motor driving system provided by the utility model, one driving motor can be independently started or two driving motors can be simultaneously started so as to realize low-energy-consumption operation of the whole vehicle or acceleration of the whole vehicle. The length of the motor shaft can be reduced by the two motor stators which are partially sleeved along the axis of the motor shaft, so that the size of the wheel in the tread direction is reduced, the space occupancy rate and the weight are reduced, and the manufacturing cost is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of motor drive, and more specifically, relates to a dual-motor drive system and a vehicle. Background Art

[0002] Vehicles have increasingly higher requirements for power and economy. The mainstream approach is to use a high-power drive motor system to meet the vehicle's ultimate acceleration performance. When the motor torque required for daily use of the vehicle is relatively small, the daily driving conditions cannot fall into the motor's high efficiency zone. The high-power drive motor system has high power consumption, and the motor cannot meet the low power consumption requirements.

[0003] In order to solve the problem that high-power drive motors have high power consumption and are difficult to meet low power consumption requirements, dual-motor drive is usually adopted. Only a single motor is turned on in low-power state, and both motors are turned on in high-power state. However, the dual-motor structure will increase the axial length of the drive motor as a whole, increase the size of the wheel in the track direction, occupy a large space, and have a large weight, which increases the manufacturing cost. Utility Model Content

[0004] The utility model aims to provide a dual-motor drive system, aiming to solve the problem that a dual-motor structure will increase the size of the wheel in the wheelbase direction, occupy a large space, have a large weight, and increase the manufacturing cost.

[0005] To achieve the above object, the technical solution adopted by the utility model is: to provide a dual-motor drive system, including a motor housing and two drive motors, wherein the two drive motors are arranged inside the motor housing;

[0006] The driving motor comprises a motor shaft, a motor rotor and a motor stator, wherein the motor rotor is mounted on the motor shaft, the motor stator is fixedly arranged and sleeved on the outer circumference of the motor rotor, and the two motor shafts are coaxially arranged and commonly connected to a reducer;

[0007] The inner diameter of one of the motor stators is greater than the outer diameter of the other motor stator, and the two motor stators are partially nested with each other along the axial direction to reduce the length of the motor shaft.

[0008] In a possible implementation, the two drive motors include a synchronous motor and an asynchronous motor respectively;

[0009] The synchronous motor is driven separately to reduce the energy consumption of the whole vehicle;

[0010] The synchronous motor and the asynchronous motor are driven simultaneously to improve the acceleration performance of the entire vehicle.

[0011] In a possible implementation, the inner diameter of the motor stator of the synchronous motor is larger than the outer diameter of the motor stator of the asynchronous motor, and the motor stator of the asynchronous motor is partially inserted into the motor stator of the synchronous motor along the axial direction.

[0012] In a possible implementation, the synchronous motor is a three-phase permanent magnet synchronous motor.

[0013] In a possible implementation, the asynchronous motor is a three-phase squirrel cage asynchronous motor.

[0014] In a possible implementation, the dual-motor drive system also includes a controller, in which two power modules are disposed, and the two drive motors are electrically connected to the two power modules in a one-to-one correspondence, and the two power modules are used to individually control the corresponding drive motors.

[0015] In a possible implementation manner, the power module is an inverter power module.

[0016] In a possible implementation, the two drive motors, the controller, and the reducer are disposed together inside the motor housing.

[0017] In a possible implementation manner, the two motor shafts are integrally formed.

[0018] The beneficial effect of a dual-motor drive system provided by the utility model is that: compared with the prior art, two drive motors are installed together in the motor housing, and the motor shafts of the two drive motors are coaxially arranged and connected to the reducer together. Among them, the inner diameter of the motor stator of one drive motor is larger than the outer diameter of the motor stator of the other drive motor, and the motor stator with a smaller outer diameter partially penetrates into the motor stator with a larger inner diameter along the axial direction of the motor shaft, thereby shortening the overall length of the motor shaft. A dual-motor drive system provided by the utility model can start one drive motor alone or start two drive motors at the same time to achieve low-energy operation of the whole vehicle or acceleration of the whole vehicle. The two motor stators that are partially mounted along the axis of the motor shaft can reduce the length of the motor shaft, thereby reducing the size in the wheel track direction, reducing space occupancy and weight, and reducing manufacturing costs.

[0019] The utility model also provides a vehicle, comprising the dual-motor drive system.

[0020] The beneficial effect of a vehicle provided by the utility model is that: compared with the prior art, the vehicle uses the above-mentioned dual-motor drive system, and therefore has the same beneficial effect as the above-mentioned dual-motor drive system. The vehicle can start one drive motor alone or two drive motors at the same time to achieve low-energy operation of the whole vehicle or acceleration of the whole vehicle. Along the axis of the motor shaft, the two motor stators that are partially mounted can reduce the length of the motor shaft, thereby reducing the size in the wheel track direction, reducing the space occupancy rate and weight, and reducing the manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A schematic diagram of the lateral structure of a dual-motor drive system provided by the utility model;

[0023] Figure 2 A cross-sectional structural diagram of a dual-motor drive system provided by the utility model;

[0024] Figure 3 The CLTC operating point distribution of a common high-power single-motor drive system vehicle;

[0025] Figure 4 The CLTC operating point distribution of the dual-motor drive system provided by the utility model.

[0026] Description of reference numerals:

[0027] 1. Synchronous motor; 2. Asynchronous motor; 3. Motor shaft; 4. Motor rotor; 5. Motor stator; 6. Motor housing; 7. Controller; 8. Power module; 9. Reducer. DETAILED DESCRIPTION

[0028] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] In the claims, specification and the above-mentioned drawings of the utility model, unless otherwise clearly defined, the use of terms such as "first", "second" or "third" etc. is to distinguish different objects rather than to describe a specific order.

[0030] In the claims, specification and the above-mentioned drawings of the utility model, unless otherwise explicitly defined, directional words, such as the terms "center", "lateral", "longitudinal", "horizontal", "vertical", "top", "bottom", "inside", "outside", "up", "down", "front", "back", "left", "right", "clockwise", "counterclockwise", "high", "low", etc., indicating directions or positional relationships are based on the directions and positional relationships shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the specific protection scope of the utility model.

[0031] See also Figure 1 and Figure 2 Now, a dual-motor drive system provided by the utility model is described. A dual-motor drive system includes a motor housing 6 and two drive motors, and the two drive motors are arranged inside the motor housing 6; the drive motor includes a motor shaft 3, a motor rotor 4 and a motor stator 5, the motor rotor 4 is installed on the motor shaft 3, the motor stator 5 is fixedly arranged and sleeved on the outer periphery of the motor rotor 4, and the two motor shafts 3 are coaxially arranged and commonly connected to a reducer 9; the inner diameter of one motor stator 5 is larger than the outer diameter of the other motor stator 5, and the two motor stators 5 are partially sleeved on each other along the axial direction to reduce the length of the motor shaft 3.

[0032] The utility model provides a dual-motor drive system. Compared with the prior art, two drive motors are installed together in a motor housing 6, and the motor shafts 3 of the two drive motors are coaxially arranged and connected to a reducer 9. Among them, the inner diameter of the motor stator 5 of one drive motor is larger than the outer diameter of the motor stator 5 of the other drive motor, and the motor stator 5 with a smaller outer diameter penetrates into the motor stator 5 with a larger inner diameter along the axial part of the motor shaft 3, thereby shortening the overall length of the motor shaft 3. The utility model provides a dual-motor drive system, which can start one drive motor alone or start two drive motors at the same time to achieve low-energy operation of the whole vehicle or acceleration of the whole vehicle. Along the axis of the motor shaft 3, the two motor stators 5 that are partially mounted can reduce the length of the motor shaft 3, thereby reducing the size in the wheel track direction, reducing space occupancy and weight, and reducing manufacturing costs.

[0033] See also Figure 2 The two drive motors include a synchronous motor 1 and an asynchronous motor 2. The synchronous motor 1 is driven alone to reduce the energy consumption of the whole vehicle; the synchronous motor 1 and the asynchronous motor 2 are driven simultaneously to improve the acceleration performance of the whole vehicle.

[0034] The synchronous motor 1 is the main drive and is in full-time working state. The asynchronous motor 2 is the auxiliary drive and cooperates with the synchronous motor 1 to work at the right time. If the synchronous motor 1 is turned on alone, the whole vehicle is in a low energy consumption state, and the whole vehicle is in a deceleration or idling state; if the synchronous motor 1 and the asynchronous motor 2 are turned on at the same time, the whole vehicle is in a high energy consumption state, such as a sudden acceleration state.

[0035] Specifically, the inner diameter of the motor stator 5 of the synchronous motor 1 is larger than the outer diameter of the motor stator 5 of the asynchronous motor 2, and the motor stator 5 of the asynchronous motor 2 is partially inserted into the motor stator 5 of the synchronous motor 1 along the axial direction. In order not to affect the independent operation of the synchronous motor 1 or the synchronous operation of the synchronous motor 1 and the asynchronous motor 2, the length of the motor stator 5 of the asynchronous motor 2 inserted into the motor stator 5 of the synchronous motor 1 is generally not more than 1 / 3 of the axial length of the motor stator 5 of the synchronous motor 1.

[0036] Preferably, the synchronous motor 1 is a three-phase permanent magnet synchronous motor 1. The permanent magnet synchronous motor 1 uses permanent magnets to provide excitation, which makes the motor structure simpler, reduces processing and assembly costs, and eliminates collector rings and brushes that are prone to problems, thereby improving the reliability of motor operation; and because no excitation current is required, there is no excitation loss, which improves the efficiency and power density of the motor.

[0037] Preferably, the asynchronous motor 2 is a three-phase squirrel cage asynchronous motor 2. Among them, the squirrel cage asynchronous motor is mainly composed of two parts, a stator and a rotor, and there is an air gap between the stator and the rotor. The rotor winding is used to generate an induced potential and an electromagnetic torque. It is divided into two types: squirrel cage type and winding type. The squirrel cage rotor winding is a self-short-circuited winding. A conductor (made of copper or aluminum) is placed in each slot of the rotor. The conductor is longer than the iron core. Two end rings are used to short-circuit the conductor at both ends of the iron core to form a short-circuited winding. If the iron core is removed, the remaining winding is shaped like a squirrel cage, so it is called a squirrel cage winding.

[0038] In some embodiments, see Figure 2 The dual-motor drive system also includes a controller 7, which is located above the two drive motors. Two power modules 8 are arranged in the controller 7, and the two power modules 8 are arranged in parallel. The two drive motors are electrically connected to the two power modules 8 one by one. Any one of the two power modules 8 can be turned on separately to control the corresponding drive motor separately; the two power modules 8 can also be turned on at the same time to control the two drive motors at the same time to achieve torque and power superposition.

[0039] Specifically, the power module 8 is an inverter power module 8. The inverter power module 8 is a DC to AC transformer module, which is actually a voltage inversion process like a converter.

[0040] In addition, the two drive motors, the controller 7 and the reducer 9 are jointly arranged inside the motor housing 6, and space is reserved inside the motor housing 6 for arranging the drive motors, the controller 7 and the reducer 9. The above-mentioned components are integrated into the motor housing 6, which can improve the integration of the dual-motor drive system and reduce space occupancy.

[0041] See also Figure 2 The two motor shafts 3 are integrally formed. In other words, the two drive motors share one motor shaft 3. The motor shaft 3 is divided into the two motor shafts 3 in different axial regions. The overall motor shaft 3 has better structural strength. The two ends of the motor shaft 3 are rotatably mounted on the two ends of the motor housing 6 through bearing assemblies.

[0042] Based on the same inventive concept, the utility model also provides a vehicle, which uses the above-mentioned dual-motor drive system, and thus has the same beneficial effects as the above-mentioned dual-motor drive system. The vehicle can start one drive motor alone or two drive motors at the same time to achieve low-energy operation of the whole vehicle or acceleration of the whole vehicle. Along the axis of the motor shaft 3, the two motor stators 5 partially set can reduce the length of the motor shaft 3, thereby reducing the size in the wheel track direction, reducing the space occupancy rate and weight, and reducing the manufacturing cost.

[0043] The above dual-motor drive system is compared with the ordinary high-power motor drive device. The peak power and peak torque are the same. For the same vehicle, the acceleration performance and power consumption performance are shown in Table 1.

[0044]

[0045] Table 1

[0046] Also, see Figure 3 and Figure 4 , which can intuitively show the specific operating point distribution information of ordinary single-motor drive and dual-motor drive in this application.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A dual-motor drive system, characterized in that: It comprises a motor housing (6) and two drive motors, wherein the two drive motors are arranged inside the motor housing (6); The drive motor comprises a motor shaft (3), a motor rotor (4) and a motor stator (5); the motor rotor (4) is mounted on the motor shaft (3); the motor stator (5) is fixedly arranged and sleeved on the outer periphery of the motor rotor (4); the two motor shafts (3) are coaxially arranged and commonly connected to a reducer (9); The inner diameter of one of the motor stators (5) is greater than the outer diameter of the other motor stator (5), and the two motor stators (5) are partially fitted to each other along the axial direction to reduce the length of the motor shaft (3).

2. A dual-motor drive system as claimed in claim 1, characterized in that: The two drive motors respectively include a synchronous motor (1) and an asynchronous motor (2); The synchronous motor (1) is driven independently to reduce the energy consumption of the whole vehicle; The synchronous motor (1) and the asynchronous motor (2) are driven simultaneously to improve the acceleration performance of the entire vehicle.

3. A dual-motor drive system as claimed in claim 2, characterized in that: The inner diameter of the motor stator (5) of the synchronous motor (1) is greater than the outer diameter of the motor stator (5) of the asynchronous motor (2), and the motor stator (5) of the asynchronous motor (2) is partially inserted into the motor stator (5) of the synchronous motor (1) along the axial direction.

4. A dual-motor drive system as claimed in claim 2, characterized in that: The synchronous motor (1) is a three-phase permanent magnet synchronous motor (1).

5. A dual-motor drive system as claimed in claim 2, characterized in that: The asynchronous motor (2) is a three-phase squirrel-cage asynchronous motor (2).

6. A dual-motor drive system as claimed in claim 1, characterized in that: The dual-motor drive system also includes a controller (7), wherein two power modules (8) are arranged in the controller (7), and the two drive motors are electrically connected to the two power modules (8) in a one-to-one correspondence, and the two power modules (8) are used to independently control the corresponding drive motors.

7. A dual-motor drive system as claimed in claim 6, characterized in that: The power module (8) is an inverter power module (8).

8. A dual-motor drive system as claimed in claim 7, characterized in that: The two driving motors, the controller (7) and the reducer (9) are arranged together inside the motor housing (6).

9. A dual-motor drive system according to any one of claims 1 to 8, characterized in that: The two motor shafts (3) are integrally formed.

10. A vehicle, characterized in that: Comprising a dual-motor drive system as described in any one of claims 1-9.

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