A vibration damping device for a vehicle driven by in-wheel motors

Abstract

The present invention discloses a vibration damping device for a vehicle driven by in-wheel motors, which includes a vehicle frame, wheels, a suspension, in-wheel motors, distributed batteries, a main battery, distributed battery springs, distributed battery shock absorbers, main battery springs and main battery shock absorbers. The distributed batteries are connected to the main battery. The main battery is connected to the vehicle frame through the main battery springs and the main battery shock absorbers. The in-wheel motors are located inside the wheels, and the in-wheel motors are connected to the vehicle frame through the suspension. The distributed batteries are connected to the in-wheel motors through the distributed battery springs and the distributed battery shock absorbers. The present invention can improve the ride comfort of the vehicle driven by in-wheel motors.

Description

Technical Field

[0001] The present invention belongs to the technical field of automotive chassis, and specifically relates to a vibration damping device for a vehicle driven by in-wheel motors. Background Art

[0002] New energy vehicles are developing rapidly, and electric vehicles have become a major development direction of new energy vehicles. Compared with traditional vehicles, electric vehicles have the advantages of zero pollution and low noise, and are the mainstream of the current development of new energy vehicles. In-wheel motor drive is a development direction of electric vehicles, which has many advantages compared with other drive forms. However, due to the in-wheel motor, the unsprung mass of the whole vehicle increases significantly, resulting in poor ride comfort and vehicle stability of the whole vehicle.

[0003] To solve the above problems and improve the ride comfort of the vehicle, manufacturers mainly improve the ride comfort of the whole vehicle from aspects such as suspension lightweighting, dynamic damping absorption of the motor body, and semi-active suspension. The lightweighting method is restricted by factors such as materials and strength; although the dynamic damping absorption system can well improve the vertical characteristics of the whole vehicle, it will make the wheel mechanism more complex and the overall mass larger; the semi-active suspension uses various control algorithms to control the suspension, but the structure is complex and the cost is high.

[0004] Chinese Patent with Publication No. CN105450099A discloses an in-wheel motor electromagnetic vibration damping device for an electric vehicle, including an in-wheel motor, a signal acquisition circuit, a core control unit, and a drive circuit. During operation, the signal acquisition circuit acquires the voltage, current of the in-wheel motor, and the current of the compensation winding and sends them to the core control unit. The control unit outputs a PWM drive signal to the drive bridge arm to close-loop control the current magnitude of the compensation winding. However, this device starts from improving the distorted magnetic field inside the in-wheel motor to reduce torque ripple, without considering the real-time performance of the control system. Chinese Patent with Publication No. CN103921637A discloses a high-speed in-wheel vibration damping device and an electric vehicle wheel, including a damping shock absorber and a spring shock absorber. It improves the ride comfort and comfort of a vehicle driven by an in-wheel motor by transmitting the acting force and reaction force between the wheel axle and the motor through the in-wheel vibration damping device. Although this device has a compact structure, the manufacturing process is complex.

[0005] Adopting the scheme of a dynamic vibration absorber can well reduce the dynamic load of the wheel and improve the ride comfort of the vehicle. However, it needs to have a large enough mass to play a necessary role, which will increase the mass of the whole vehicle, thereby reducing the power performance, braking performance, and economy of the vehicle. At present, there is no vibration damping device in China that has a simple structure and fully utilizes the mass of the power battery to improve the ride comfort of a vehicle driven by an in-wheel motor. Therefore, a vibration damping device that uses the power battery of an electric vehicle as the mass of the dynamic vibration absorber is designed. Summary of the Invention

[0006] In view of the above technical problems, the present invention provides a vibration damping device that uses a power battery as the mass of a dynamic vibration absorber to solve the problems of poor ride comfort of a vehicle driven by in-wheel motors and the underutilization of the mass of the power battery.

[0007] The present invention is achieved through the following technical solutions:

[0008] A vibration damping device for a vehicle driven by in-wheel motors includes a vehicle frame, wheels, a suspension, in-wheel motors, distributed batteries, a main battery, distributed battery springs, distributed battery shock absorbers, a main battery spring, and a main battery shock absorber; the distributed batteries are connected to the main battery, the main battery is connected to the vehicle frame through the main battery spring and the main battery shock absorber, the in-wheel motors are located inside the wheels, the in-wheel motors are connected to the vehicle frame through the suspension, the distributed batteries are connected to the in-wheel motors through the distributed battery springs and the distributed battery shock absorbers, and the in-wheel motors are connected to the vehicle frame through the suspension.

[0009] Further, the distributed batteries have a shock-resistant design and serve as dynamic vibration absorbers for suppressing wheel vibrations.

[0010] Further, the in-wheel motors are permanent magnet synchronous motors or permanent magnet brushless motors.

[0011] Further, the main battery is a lithium-ion battery, a lithium iron phosphate battery, a ternary lithium battery, or the like.

[0012] Compared with the prior art, the beneficial effects of the invention are as follows:

[0013] Vehicles driven by in-wheel motors have the disadvantage of deteriorating ride comfort, and a dynamic vibration absorber requires a sufficiently large mass to improve the vertical performance of the vehicle. Therefore, the present invention makes full use of the existing mass of the power battery and reasonably divides the battery into a main battery and distributed batteries, with the main battery and distributed batteries serving as the mass of the dynamic vibration absorber; the distributed batteries, distributed battery shock absorbers, and distributed battery springs form a damped dynamic vibration absorber, which forms a resonance system with the unsprung mass to weaken the energy generated by wheel vibrations; the main battery, main battery shock absorbers, and main battery spring form a damped dynamic vibration absorber, which forms a resonance system with the sprung mass to weaken the energy generated by vehicle frame vibrations. This device improves the ride comfort of the entire vehicle and has the advantage of a simple structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a structural diagram of the present invention;

[0015] Figure 2 is a dynamic structural diagram of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] As Figure 1As shown in the figure, a vibration damping device for a wheel hub motor-driven vehicle includes a wheel 1, a wheel hub motor 2, a distributed battery 3, a distributed battery shock absorber 4, a main battery 5, a main battery shock absorber 6, a main battery spring 7, a vehicle frame 8, and a distributed battery spring 9; the wheel hub motor 2 is located inside the wheel 1, the wheel hub motor 2 is connected to the vehicle frame 8 through a suspension, the distributed battery 3 is connected to the main battery 5, the distributed battery 3 is connected to the wheel hub motor 2 through a distributed battery spring 9 and a distributed battery shock absorber 4, and the main battery 5 is connected to the vehicle frame 8 through a main battery spring 7 and a main battery shock absorber 6. When the wheel 1 vibrates due to the impact of the ground, the distributed battery 3, the distributed battery shock absorber 4, and the distributed battery spring 9 form a damping dynamic vibration absorber, and the main battery 5, the main battery shock absorber 6, and the main battery spring 7 form a damping dynamic vibration absorber. Among them, the distributed battery shock absorber 4 is an adjustable damping shock absorber, which can effectively broaden the vibration absorption frequency band of the dynamic vibration absorber. For the convenience of display, the suspension structure is not drawn.

[0017] The distributed battery 3 has a shock-resistant design and serves as a dynamic vibration absorber for suppressing wheel vibrations.

[0018] The wheel hub motor 2 is a permanent magnet synchronous motor or a permanent magnet brushless motor.

[0019] The main battery 5 is a lithium-ion battery, a lithium iron phosphate battery, a ternary lithium battery, etc.

[0020] Figure 2 is the dynamic structure diagram of the present invention, where m u is the unsprung mass excluding the mass of the distributed battery, m b is the mass of the distributed battery; K t 、K m1 are the tire stiffness and the distributed battery spring stiffness respectively, and C m1 is the damping coefficient of the distributed battery shock absorber.

[0021] m u and K t are the main system, m b 、K m1 and C m1 are the dynamic vibration absorber. The two form a forced vibration system of an additional damping dynamic vibration absorber, and the damping C m1 in it can effectively broaden the vibration absorption frequency band of the dynamic vibration absorber.

[0022] The damping of the vibration absorber has an impact on the amplitude of the main system. When the vibration absorber has no damping, the resonance peak of the main vibration system is infinite; when the damping of the vibration absorber is infinite, the resonance peak of the main vibration system is also infinite; only when the vibration absorber has a certain damping, the resonance peak will not be infinite. Therefore, there must be a suitable damping value that makes the resonance peak of the main vibration system the smallest, and this suitable damping value is an important task in the design of the damping dynamic vibration absorber.

[0023] The present invention has the following advantages:

[0024] 1. Without increasing the vehicle's overall mass, the mass of the power battery is utilized to achieve dynamic vibration absorption, improving the ride comfort of the vehicle.

[0025] 2. The structure is simple, and it directly absorbs the vibrations transmitted from the road surface, enhancing the fatigue durability performance of the chassis components.

[0026] 3. When the vehicle is running, the electric energy in the distributed batteries can be used to drive the wheels first. When the SOC drops to a certain value, the main battery is used for power supply or the engine is started to generate electricity.

[0027] For those skilled in the art, various modifications and changes can be made to the present invention; any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A vibration damping device for a vehicle driven by in-wheel motors, characterized in that: it includes a wheel (1), an in-wheel motor (2), a distributed battery (3), a distributed battery shock absorber (4), a main battery (5), a main battery shock absorber (6), a main battery spring (7), a vehicle frame (8) and a distributed battery spring (9); the in-wheel motor (2) is located inside the wheel (1), the in-wheel motor (2) is connected to the vehicle frame (8) through a suspension, the distributed battery (3) is connected to the main battery (5), and the distributed battery (3) is connected to the in-wheel motor (2) through the distributed battery spring (9) and the distributed battery shock absorber (4), and the main battery (5) is connected to the vehicle frame (8) through the main battery spring (7) and the main battery shock absorber (6).

2. The vibration damping device for a vehicle driven by in-wheel motors according to claim 1, characterized in that: the distributed battery (3) and the main battery (5) can transfer electric energy to each other and jointly drive the in-wheel motor.

3. The vibration damping device for a vehicle driven by in-wheel motors according to claim 1, characterized in that: the main battery (5), the main battery spring (7) and the main battery shock absorber (6) form a damped dynamic vibration absorber, and form a resonance system with the unsprung mass to weaken the energy generated by the vibration of the vehicle frame.

4. The vibration damping device for a vehicle driven by in-wheel motors according to claim 1, characterized in that: the distributed battery (3), the distributed battery shock absorber (4) and the distributed battery spring (9) form a damped dynamic vibration absorber, and form a resonance system with the sprung mass to weaken the energy generated by the vibration of the wheel.

5. The vibration damping device for a vehicle driven by in-wheel motors according to claim 1, characterized in that: the distributed battery (3) serves as a dynamic vibration absorber for suppressing the vibration of the wheel.

6. The vibration damping device for a vehicle driven by in-wheel motors according to claim 1, characterized in that: the in-wheel motor (2) is a permanent magnet synchronous motor or a permanent magnet brushless motor.

7. The vibration damping device for a vehicle driven by in-wheel motors according to claim 1, characterized in that: the main battery (5) is a lithium-ion battery, a lithium iron phosphate battery or a ternary lithium battery.

Images