CN115366699A - Vehicle vertical vibration control method and device - Google Patents

Abstract

The present invention provides a vehicle vertical vibration control method and device, wherein the vehicle is driven by an in-wheel motor and the suspension system of the vehicle uses a magneto-rheological damper. The method includes the following steps: obtaining the in-wheel motor The angular position of the rotor and the eccentricity of the stator and rotor; calculate the motor excitation of the in-wheel motor according to the angular position of the rotor and the eccentricity of the stator and rotor; obtain the vehicle body motion speed and wheel motion speed; according to the The body movement speed and the wheel movement speed determine the damping force of the magneto-rheological damper; the in-wheel motor is controlled by the motor excitation, and the magnetorheological damper is controlled by the damping force control. The invention can reduce the vibration of the vehicle body, thereby improving the ride comfort and safety of the vehicle during running.

Description

Vehicle vertical vibration control method and device

technical field

The invention relates to the technical field of vehicle control, in particular to a vehicle vertical vibration control method and a vehicle vertical vibration control device.

Background technique

With the intensification of environmental problems and energy crisis, new energy vehicles have ushered in unprecedented development opportunities, and electric vehicles may become a mainstream direction of new energy development. Electric vehicles driven by in-wheel motors have eliminated structures such as transmission shafts, and arranged in-wheel motors, reduction mechanism brakes, etc. in the wheels, thus simplifying the chassis structure and improving transmission efficiency. In general, the geometric center of the stator and rotor of the in-wheel motor is concentric with the geometric center of the wheel, but under different road excitations, vehicle speeds and other factors, the air gap of the motor will be unevenly distributed along the circumference, resulting in motor excitation that affects the smoothness of the vehicle sex.

Contents of the invention

In order to solve the above technical problems, the present invention provides a vehicle vertical vibration control method and device, which can reduce the vibration of the vehicle body, thereby improving the ride comfort and safety of the vehicle during driving.

The technical scheme that the present invention adopts is as follows:

A method for controlling vertical vibration of a vehicle, the vehicle is driven by an in-wheel motor and the suspension system of the vehicle uses a magneto-rheological damper, the method includes the following steps: obtaining the angular position of the rotor of the in-wheel motor and the stator and rotor the eccentricity of the rotor; calculate the motor excitation of the in-wheel motor according to the angular position of the rotor and the eccentricity of the stator and rotor; obtain the vehicle body movement speed and wheel movement speed; according to the body movement speed and the The moving speed of the wheel determines the damping force of the magneto-rheological damper; the hub motor is controlled with the motor excitation, and the magnetorheological damper is controlled with the damping force.

Calculating the motor excitation of the in-wheel motor according to the angular position of the rotor and the eccentricity of the stator and rotor, specifically includes: calculating according to the eccentricity of the stator and rotor and the relative distance between the stator and rotor when the in-wheel motor is not eccentric The eccentricity of the hub motor; the motor excitation is calculated according to the eccentricity of the hub motor, the relative distance between the stator and rotor when the hub motor is not eccentric, and the angular position of the rotor.

The eccentricity of the hub motor is calculated according to the following formula:

ε=r/δ ₀

Wherein, ε is the eccentricity of the hub motor, r is the eccentricity of the stator and rotor, and _δ0 is the relative distance between the stator and rotor when the hub motor is not eccentric.

The motor excitation is calculated according to the following formula:

Wherein, F is the excitation of the motor, k _μ is the saturation coefficient of the magnetic circuit, k _en is the equivalent electromagnetic stiffness, and θ _r is the angular position of the rotor.

The hyperbolic tangent model is used to control the magnetorheological damper.

Determining the damping force of the magneto-rheological damper according to the movement speed of the vehicle body and the movement speed of the wheels specifically includes: calculating the relative speed of the suspension system according to the movement speed of the vehicle body and the movement speed of the wheels; if If the vehicle body motion speed is in the same direction as the wheel motion speed and the relative speed of the suspension system is negative, then the damping force of the magneto-rheological damper is determined as the first damping force; otherwise, the magneto-rheological damper is determined as the first damping force; The damping force of the variable damper is determined as the second damping force, wherein the second damping force is greater than the first damping force.

A vehicle vertical vibration control method further includes: when the relative speed of the vehicle body movement speed, the wheel movement speed and the suspension system changes presetly, according to the requirements for ride comfort and wheel dynamic load Delay or advance the switching of the damping force.

The preset changes include: the movement speed of the vehicle body is always positive, while the relative movement speed of the suspension system changes from positive to negative; the movement speed of the vehicle body changes from positive to negative, while the relative movement speed of the suspension system Relative motion velocity is always negative.

A vehicle vertical vibration control device, the vehicle is driven by an in-wheel motor and the suspension system of the vehicle uses a magnetorheological damper, the device includes: a first acquisition module, the first acquisition module is used to acquire The angular position of the hub motor rotor and the eccentricity of the stator and rotor; a calculation module, the calculation module is used to calculate the motor excitation of the hub motor according to the angular position of the rotor and the eccentricity of the stator and rotor; the second An acquisition module, the second acquisition module is used to acquire the body movement speed and wheel movement speed of the vehicle; a determination module, the determination module is used to determine the magnetic current according to the body movement speed and the wheel movement speed The damping force of the variable damper; a control module, the control module is used to control the hub motor with the motor excitation, and control the magneto-rheological damper with the damping force.

Beneficial effects of the present invention:

The invention calculates the motor excitation by obtaining the angular position of the hub motor rotor and the eccentricity of the stator and rotor, and determines the damping force of the magneto-rheological damper by obtaining the vehicle body motion speed and wheel motion speed, and controls the hub motor with motor excitation And the magneto-rheological damper is controlled by the damping force, thereby, the vibration of the vehicle body can be reduced, thereby improving the comfort and safety of the vehicle during driving.

Description of drawings

Fig. 1 is the flowchart of the vehicle vertical vibration control method of the embodiment of the present invention;

Fig. 2 is a schematic diagram of controlling an in-wheel motor according to an embodiment of the present invention;

Fig. 3 is a schematic diagram of controlling the suspension system according to an embodiment of the present invention;

FIG. 4 is a block diagram of a vehicle vertical vibration control device according to an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The vehicle of the embodiment of the present invention is driven by an in-wheel motor, and the suspension system of the vehicle adopts a magneto-rheological damper, which is a semi-active suspension, that is, the control object of the vehicle drive control system is the in-wheel motor, and the vehicle suspension control system The control object is the magnetorheological damper.

As shown in Figure 1, the vehicle vertical vibration control method of the embodiment of the present invention includes the following steps:

S1, obtaining the angular position of the rotor of the in-wheel motor and the eccentricity of the stator and rotor.

In one embodiment of the present invention, the in-wheel motor information of the vehicle can be collected in real time through the information collection system inside the in-wheel motor, so that the angular position of the rotor of the in-wheel motor and the eccentricity of the stator and rotor can be obtained. Wherein, the hub motor may be a permanent magnet synchronous motor, an asynchronous motor or a switched reluctance motor.

S2, calculating the motor excitation of the hub motor according to the angular position of the rotor and the eccentricity of the stator and rotor.

In one embodiment of the present invention, the eccentricity of the hub motor can be calculated according to the eccentricity of the stator and rotor and the relative distance between the stator and rotor when the hub motor is not eccentric, and the eccentricity of the hub motor can be calculated according to the eccentricity of the hub motor and the stator and rotor when the hub motor is not eccentric. The motor excitation is calculated based on the relative distance between them and the angular position of the rotor.

Specifically, a position sensor can be installed at the position of the rotor of the hub motor and the stator and rotor, and the relative distance between the stator and rotor when the hub motor is not eccentric can be obtained through the position sensor, thus, the eccentricity of the hub motor can be obtained, wherein the hub motor The eccentricity of can be calculated according to the following formula:

ε=r/δ ₀

Among them, ε is the eccentricity of the hub motor, r is the eccentricity of the stator and rotor, and _δ0 is the relative distance between the stator and rotor when the hub motor is not eccentric.

After the eccentricity of the hub motor is calculated by the above formula, the motor excitation can be calculated according to the air gap electromagnetic analysis model of the hub motor. The calculation formula of the motor excitation is as follows:

Among them, F is the motor excitation, k _μ is the saturation coefficient of the magnetic circuit, k _en is the equivalent electromagnetic stiffness, and θ _r is the angular position of the rotor.

S3. Obtain the body movement speed and the wheel movement speed of the vehicle.

In one embodiment of the present invention, the vehicle body movement speed and wheel movement speed can be collected in real time by installing speed sensors on the vehicle body and wheels.

S4. Determine the damping force of the magneto-rheological damper according to the movement speed of the vehicle body and the movement speed of the wheels.

Specifically, first, the relative velocity of the suspension system can be calculated according to the movement velocity of the vehicle body and the movement velocity of the wheels. Among them, the suspension system is located between the vehicle body and the wheels. Since the body movement speed Xs and the wheel movement speed Xt can be collected through the speed sensor, the relative speed of the suspension system can be calculated indirectly according to the movement speed of the body and wheels, that is, the suspension The relative velocity of the system is Xs-Xt.

Then, two damping forces, the first damping force c _fmin and the second damping force c _fmax , can be set for selection, and the suspension control unit can select an appropriate damping force according to the vertical vibration state of the vehicle. If the motion speed of the body is in the same direction as the wheel motion speed and the relative speed of the suspension system is negative, the damping force of the magneto-rheological damper is determined as the first damping force c _fmin , otherwise the damping force of the magneto-rheological damper is determined as is the second damping force c _fmax . Wherein, the second damping force c _fmax is greater than the first damping force c _fmin . That is to say, when the movement speed of the body is in the same direction as the movement speed of the wheels and the relative speed of the suspension system is negative, the magneto-rheological damper can be controlled to generate a small damping force; when the movement speed of the body is opposite to the movement speed of the wheels Or when the relative speed of the suspension system is positive, the magneto-rheological damper can be controlled to generate a larger damping force.

Since the vehicle is moving vertically, it can be classified according to the direction and size of the vehicle body and wheel movement speed collected by the speed sensor. The direction of the moving speed of the body and the wheels can be specified as up and down, and the speed when the moving speed of the body and the moving speed of the wheel is recorded is equal. At the same time, the size of the two can be defined according to the relationship between the moving speed of the body and the moving speed of the wheel. If At this time, the movement speed of the body is greater than the movement speed of the wheels, then the movement speed of the body is large and the movement speed of the wheels is small; For example, the movement speed of the body is Xs, and the movement speed of the wheels is Xt. According to the direction and size of Xs, it can be divided into four states: up small, up big, down small, and down big. At the same time, it can be divided into four states according to the direction and size of Xt Divided into four states: up small, up big, down small, and down big.

Combined with the division of the above-mentioned vehicle body movement speed and wheel movement speed state, it can be stipulated that Xs up small Xt down big is R1, Xs up big Xt down small is R2, Xs up big Xt up small is R3, Xs up small Xt up big is R4 , Xs lower big Xt upper big is R5, Xs lower big Xt upper small is R6, Xs lower big Xt lower small is R7, Xs lower small Xt lower big is R8, according to the movement state of the body and wheels, the vehicle can be The vertical vibration is divided into eight states: R1, R2, R3, R4, R5, R6, R7, and R8. When the motion speed of the vehicle body is in the same direction as the wheel motion speed and the relative speed of the suspension system is negative, that is, when the vertical vibration state of the vehicle is R1, R2, R3, R5, R6 and R7, the magnetorheological damper can be The damping force is determined as the first damping force c _fmin , and when the vertical vibration state of the vehicle is R4 and R8, the damping force of the magneto-rheological damper can be determined as the second damping force c _fmax .

S5, the hub motor is controlled by the motor excitation, and the magneto-rheological damper is controlled by the damping force.

Fig. 2 is a schematic diagram of motor excitation controlling the in-wheel motor. It can be seen from Figure 2 that the in-wheel motor is connected to the vehicle body and the wheel, and the in-wheel motor information of the vehicle can be collected in real time through the information collection system inside the in-wheel motor. , to control the hub motor with motor excitation. Wherein, the wheel movement speed Xt and the vehicle body movement speed Xs can be obtained by a speed sensor.

In one embodiment of the present invention, as shown in Figure 3, the information collection system inside the hub motor can collect the hub motor information and calculate the motor excitation of the hub motor, and control the hub motor of the model vehicle through the motor excitation . Specifically, the body movement speed and the wheel movement speed can be obtained through the speed sensors on the body and wheels, and the relative speed of the suspension system can be calculated according to the movement speed of the body and wheels. Then, the suspension control unit can control the current I to Determine the damping force of the magnetorheological damper, and control the magnetorheological damper with the damping force, and then control the model vehicle.

In one embodiment of the present invention, the hyperbolic tangent model can be used to control the magneto-rheological damper. Since the structure of the hyperbolic tangent model is relatively simple, there are fewer adjustment factors, the process of fitting parameters is easier to realize, and it can better describe the characteristics of the hysteresis curve, so the control of the magnetorheological damper based on this model is also relatively easy to realize , and the hyperbolic tangent model is more convenient when solving the inverse model. The mathematical expression of the hyperbolic tangent model of the magnetorheological damper is F=αtanh(βta+δsgn(x))+cx+kx+f0, where α is the hysteresis proportional factor, and β is the hysteresis slope proportional factor , δ is the half-width of the hysteresis loop, c is the damping coefficient after yielding, k is the stiffness coefficient, and f0 is the bias force.

In the above mathematical expression of the hyperbolic tangent model of the magneto-rheological damper, since there is no direct functional relationship between the parameters β, δ and f0, it is necessary to fit the three parameters under different control currents. By using the fitting device to fit the three parameters under different control currents, the following fitting relationship is obtained:

The mathematical expression of the damping force of the fitted magnetorheological damper can be transformed into:

F=(1101I+59.14)tanh(0.04 9(x+0.4607sgn(x)))+(6.926I+8.37)x+(-3.172I+0.64)x-30.89

Among them, x is the displacement of the damper rod, F is the damping force, and I is the control current.

The control current in the above mathematical expression of the damping force of the magnetorheological damper is the input of the magnetorheological damper, and the damping force is the output of the magnetorheological damper, and the displacement of the damper rod can be obtained through the position sensor, thus, After the damping force is determined, the corresponding control current can be calculated according to the hyperbolic tangent model, so that the magneto-rheological damper can be controlled with the corresponding control current.

In addition, in an embodiment of the present invention, when the relative speed of the vehicle body movement speed, wheel movement speed and suspension system changes presetly, it can be delayed or advanced according to the requirements for ride comfort and wheel dynamic load. The damping force is switched to control the vertical vibration of the vehicle. Among them, the preset changes include: the direction of the movement speed of the body is always upward, while the relative movement speed of the suspension system changes from positive to negative; the direction of the movement speed of the body changes from up to down, and the relative movement speed of the suspension system is always burden. Specifically, when the direction of the body motion speed Xs is always upward, and the relative motion speed of the suspension system changes from positive to negative, the damping force of the magneto-rheological damper also changes from c _fmax to c _fmin . For the influence of force on the dynamic load of the wheel, it is necessary to delay the change of damping, that is, when Xs is slightly greater than Xt, then the damping is reduced. At this time, the vertical vibration state of the vehicle changes from R1 or R2 or R3 to R4. When the direction of the body movement speed Xs changes from up to down, and the relative movement speed Xs-Xt of the suspension system is always negative, the damping force of the magneto-rheological damper changes from c _fmin to c _fmax , and the vertical direction of the vehicle The vibration state changes from R1 or R4 to R6 or R7. At this time, if the influence of the force on ride comfort is considered, the damping needs to be changed in advance, that is, when Xs does not decrease to zero, the damping should be increased. If considering The effect of the force on the dynamic load of the wheel requires delaying the change of the damper damping. Therefore, the suspension control unit will switch the magnetorheological damper in time according to the requirements of ride comfort or load, so as to improve the ride comfort of the vehicle.

According to the vehicle vertical vibration control method of the embodiment of the present invention, the motor excitation is calculated by obtaining the angular position of the hub motor rotor and the eccentricity of the stator and rotor, and the magneto-rheological damper is determined by obtaining the vehicle body motion speed and wheel motion speed. The damping force controls the wheel hub motor with the motor excitation and the magneto-rheological damper with the damping force, thereby reducing the vibration of the vehicle body and improving the ride comfort and safety of the vehicle during driving.

In order to realize the vehicle vertical vibration control method of the above embodiments, the present invention further proposes a vehicle vertical vibration control device.

As shown in FIG. 4 , the vehicle vertical vibration control device according to the embodiment of the present invention includes: a first acquisition module 10 , a calculation module 20 , a second acquisition module 30 , a determination module 40 and a control module 50 . Among them, the first acquisition module 10 is used to acquire the angular position of the hub motor rotor and the eccentricity of the stator and rotor; the calculation module 20 is used to calculate the motor excitation of the hub motor according to the angular position of the rotor and the eccentricity of the stator and rotor; the second acquisition module 30 is used to obtain the vehicle body movement speed and wheel movement speed; the determination module 40 is used to determine the damping force of the magnetorheological damper according to the body movement speed and wheel movement speed; the control module 50 is used to control the in-wheel motor with motor excitation , and the magnetorheological damper is controlled by the damping force.

In an embodiment of the present invention, the first acquisition module 10 can acquire the rotational angle position of the rotor of the in-wheel motor and the eccentricity of the stator and rotor through the in-wheel motor information collection system inside the vehicle. Wherein, the hub motor may be a permanent magnet synchronous motor, an asynchronous motor or a switched reluctance motor.

In one embodiment of the present invention, the calculation module 20 can calculate the eccentricity of the hub motor according to the eccentricity of the stator and the rotor and the relative distance between the stator and the rotor when the hub motor is not eccentric, and calculate the eccentricity of the hub motor according to the eccentricity of the hub motor, the non-eccentricity of the hub motor The motor excitation is calculated based on the relative distance between the stator and rotor and the angular position of the rotor.

Specifically, a position sensor can be installed at the position of the rotor of the hub motor and the stator and rotor, and the relative distance between the stator and rotor when the hub motor is not eccentric can be obtained through the position sensor, thus, the eccentricity of the hub motor can be obtained, wherein the hub motor The eccentricity of can be calculated according to the following formula:

ε=r/δ ₀

Among them, ε is the eccentricity of the hub motor, r is the eccentricity of the stator and rotor, and _δ0 is the relative distance between the stator and rotor when the hub motor is not eccentric.

After the eccentricity of the hub motor is calculated by the above formula, the motor excitation can be calculated according to the air gap electromagnetic analysis model of the hub motor. The calculation formula of the motor excitation is as follows:

Among them, F is the motor excitation, k _μ is the saturation coefficient of the magnetic circuit, k _en is the equivalent electromagnetic stiffness, and θ _r is the angular position of the rotor.

In an embodiment of the present invention, the second acquisition module 30 can collect the vehicle body movement speed and wheel movement speed in real time by installing speed sensors on the vehicle body and wheels.

The determining module 40 determines the damping force of the magneto-rheological damper according to the moving speed of the vehicle body and the moving wheels specifically includes the following steps: First, the relative speed of the suspension system can be calculated according to the moving speed of the vehicle body and the moving wheels. Among them, the suspension system is located between the vehicle body and the wheels. Since the body movement speed Xs and the wheel movement speed Xt can be collected through the speed sensor, the relative speed of the suspension system can be calculated indirectly according to the movement speed of the body and wheels, that is, the suspension The relative velocity of the system is Xs-Xt.

Then, two damping forces, the first damping force c _fmin and the second damping force c _fmax , can be set for selection, and the suspension control unit can select an appropriate damping force according to the vertical vibration state of the vehicle. If the motion speed of the body is in the same direction as the wheel motion speed and the relative speed of the suspension system is negative, the damping force of the magneto-rheological damper is determined as the first damping force c _fmin , otherwise the damping force of the magneto-rheological damper is determined as is the second damping force c _fmax . Wherein, the second damping force c _fmax is greater than the first damping force c _fmin . That is to say, when the movement speed of the body is in the same direction as the movement speed of the wheels and the relative speed of the suspension system is negative, the magneto-rheological damper can be controlled to generate a small damping force; when the movement speed of the body is opposite to the movement speed of the wheels Or when the relative speed of the suspension system is positive, the magneto-rheological damper can be controlled to generate a larger damping force.

Since the vehicle is moving vertically, it can be classified according to the direction and size of the vehicle body and wheel movement speed collected by the speed sensor. The direction of the moving speed of the body and the wheels can be specified as up and down, and the speed when the moving speed of the body and the moving speed of the wheel is recorded is equal. At the same time, the size of the two can be defined according to the relationship between the moving speed of the body and the moving speed of the wheel. If At this time, the movement speed of the body is greater than the movement speed of the wheels, then the movement speed of the body is large and the movement speed of the wheels is small; For example, the movement speed of the body is Xs, and the movement speed of the wheels is Xt. According to the direction and size of Xs, it can be divided into four states: up small, up big, down small, and down big. At the same time, it can be divided into four states according to the direction and size of Xt Divided into four states: up small, up big, down small, and down big.

Combined with the division of the above-mentioned vehicle body movement speed and wheel movement speed state, it can be stipulated that Xs up small Xt down big is R1, Xs up big Xt down small is R2, Xs up big Xt up small is R3, Xs up small Xt up big is R4 , Xs lower big Xt upper big is R5, Xs lower big Xt upper small is R6, Xs lower big Xt lower small is R7, Xs lower small Xt lower big is R8, according to the movement state of the body and wheels, the vehicle can be The vertical vibration is divided into eight states: R1, R2, R3, R4, R5, R6, R7, and R8. When the motion speed of the vehicle body is in the same direction as the wheel motion speed and the relative speed of the suspension system is negative, that is, when the vertical vibration state of the vehicle is R1, R2, R3, R5, R6 and R7, the magnetorheological damper can be The damping force is determined as the first damping force c _fmin , and when the vertical vibration state of the vehicle is R4 and R8, the damping force of the magneto-rheological damper can be determined as the second damping force c _fmax .

In one embodiment of the present invention, the information collection system inside the hub motor can collect the hub motor information and calculate the motor excitation of the hub motor, and the control module 50 controls the hub motor of the model vehicle through the motor excitation. Specifically, the vehicle body and wheel motion speeds can be acquired through the speed sensors on the vehicle body and wheels, and the relative speed of the suspension system can be calculated according to the motion speeds of the vehicle body and wheels. Then, the suspension control unit in the control module 50 can pass The current I is controlled to determine the damping force of the magnetorheological damper, and the damping force is used to control the magnetorheological damper, thereby controlling the model vehicle.

In an embodiment of the present invention, the control module 50 may use a hyperbolic tangent model to control the magnetorheological damper. Since the structure of the hyperbolic tangent model is relatively simple, there are fewer adjustment factors, the process of fitting parameters is easier to realize, and it can better describe the characteristics of the hysteresis curve, so the control of the magnetorheological damper based on this model is also relatively easy to realize , and the hyperbolic tangent model is more convenient when solving the inverse model. The mathematical expression of the hyperbolic tangent model of the magnetorheological damper is F=αtanh(βta+δsgn(x))+cx+kx+f0, where α is the hysteresis proportional factor, and β is the hysteresis slope proportional factor , δ is the half-width of the hysteresis loop, c is the damping coefficient after yielding, k is the stiffness coefficient, and f0 is the bias force.

In the above mathematical expression of the hyperbolic tangent model of the magneto-rheological damper, since there is no direct functional relationship between the parameters β, δ and f0, it is necessary to fit the three parameters under different control currents. By using the fitting device to fit the three parameters under different control currents, the following fitting relationship is obtained:

The mathematical expression of the damping force of the fitted magnetorheological damper can be transformed into:

F _f ＝(1101I+59.14)tanh(0.04 9(x+0.4607sgn(x)))+(6.926I+8.37)x+(-3.172I+0.64)x-30.89

Among them, x is the displacement of the damper rod, F _f is the damping force, and I is the control current.

In the above mathematical expression of the damping force of the magnetorheological damper, the control current is the input of the magnetorheological damper, and the damping force is the output of the magnetorheological damper, and the displacement of the damper rod can be obtained through the position sensor, thus , after determining the damping force, the control module 50 can calculate the corresponding control current according to the hyperbolic tangent model, so as to control the magnetorheological damper with the corresponding control current.

In addition, in an embodiment of the present invention, when the relative speed of the vehicle body movement speed, wheel movement speed and suspension system changes presetly, it can be delayed or advanced according to the requirements for ride comfort and wheel dynamic load. The damping force is switched to control the vertical vibration of the vehicle. Among them, the preset changes include: the direction of the movement speed of the body is always upward, while the relative movement speed of the suspension system changes from positive to negative; the direction of the movement speed of the body changes from up to down, and the relative movement speed of the suspension system is always burden. Specifically, when the direction of the body motion speed Xs is always upward, and the relative motion speed of the suspension system changes from positive to negative, the damping force of the magneto-rheological damper also changes from c _fmax to c _fmin . For the influence of force on the dynamic load of the wheel, it is necessary to delay the change of damping, that is, when Xs is slightly greater than Xt, then the damping is reduced. At this time, the vertical vibration state of the vehicle changes from R1 or R2 or R3 to R4. When the direction of the body movement speed Xs changes from up to down, and the relative movement speed Xs-Xt of the suspension system is always negative, the damping force of the magneto-rheological damper changes from c _fmin to c _fmax , and the vertical direction of the vehicle The vibration state changes from R1 or R4 to R6 or R7. At this time, if the influence of the force on ride comfort is considered, the damping needs to be changed in advance, that is, when Xs does not decrease to zero, the damping should be increased. If considering The effect of the force on the dynamic load of the wheel requires delaying the change of the damper damping. Therefore, the suspension control unit will switch the magnetorheological damper in time according to the requirements of ride comfort or load, so as to improve the ride comfort of the vehicle.

According to the vehicle vertical vibration control device according to the embodiment of the present invention, the angular position of the in-wheel motor rotor and the eccentricity of the stator and rotor are acquired through the first acquisition module, the calculation module calculates the motor excitation, and the vehicle body motion speed is acquired through the second acquisition module and wheel movement speed, the determination module determines the damping force of the magneto-rheological damper, the control module controls the hub motor with the motor excitation and the magnetorheological damper with the damping force, thus, the vibration of the vehicle body can be reduced, thereby improving The smoothness and safety of the vehicle during driving.

In the description of the present invention, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. "Plurality" means two or more, unless otherwise clearly and specifically defined.

In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrated; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediary, and it can be the internal communication of two components or the interaction relationship between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

In the present invention, unless otherwise clearly specified and limited, the first feature may be in direct contact with the first feature or the first and second feature may be in direct contact with the second feature through an intermediary. touch. Moreover, "above", "above" and "above" the first feature on the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. "Below", "beneath" and "beneath" the first feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is less horizontally than the second feature.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

Any process or method descriptions in flowcharts or otherwise described herein may be understood to represent modules, segments or portions of code comprising one or more executable instructions for implementing specific logical functions or steps of the process , and the scope of preferred embodiments of the invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including substantially concurrently or in reverse order depending on the functions involved, which shall It is understood by those skilled in the art to which the embodiments of the present invention pertain.

The logic and/or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced listing of executable instructions for implementing logical functions, can be embodied in any computer-readable medium, For use with instruction execution systems, devices, or devices (such as computer-based systems, systems including processors, or other systems that can fetch instructions from instruction execution systems, devices, or devices and execute instructions), or in conjunction with these instruction execution systems, devices or equipment used. For the purposes of this specification, a "computer-readable medium" may be any device that can contain, store, communicate, propagate or transmit a program for use in or in conjunction with an instruction execution system, device or device. More specific examples (non-exhaustive list) of computer-readable media include the following: electrical connection with one or more wires (electronic device), portable computer disk case (magnetic device), random access memory (RAM), Read Only Memory (ROM), Erasable and Editable Read Only Memory (EPROM or Flash Memory), Fiber Optic Devices, and Portable Compact Disc Read Only Memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program can be printed, since the program can be read, for example, by optically scanning the paper or other medium, followed by editing, interpretation or other suitable processing if necessary. The program is processed electronically and stored in computer memory.

It should be understood that various parts of the present invention can be realized by hardware, software, firmware or their combination. In the embodiments described above, various steps or methods may be implemented by software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented by any one or combination of the following techniques known in the art: Discrete logic circuits, ASICs with suitable combinational logic gates, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

Those of ordinary skill in the art can understand that all or part of the steps carried by the methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. During execution, one or a combination of the steps of the method embodiments is included.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing module, each unit may exist separately physically, or two or more units may be integrated into one module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software function modules. If the integrated modules are realized in the form of software function modules and sold or used as independent products, they can also be stored in a computer-readable storage medium.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (9)

1. a vehicle vertical vibration control method, characterized in that, the vehicle is driven by an in-wheel motor and the suspension system of the vehicle adopts a magneto-rheological damper, and the method may further comprise the steps: Obtain the angular position of the rotor of the in-wheel motor and the eccentricity of the stator and rotor; calculating the motor excitation of the in-wheel motor according to the angular position of the rotor and the eccentricity of the stator and rotor; Acquiring the body movement speed and wheel movement speed of the vehicle; determining the damping force of the magneto-rheological damper according to the moving speed of the vehicle body and the moving speed of the wheels; The hub motor is controlled by the motor excitation, and the magneto-rheological damper is controlled by the damping force. 2. The vehicle vertical vibration control method according to claim 1, wherein the motor excitation of the in-wheel motor is calculated according to the angular position of the rotor and the eccentricity of the stator and rotor, specifically comprising: calculating the eccentricity of the hub motor according to the eccentricity of the stator and rotor and the relative distance between the stator and rotor when the hub motor is not eccentric; The motor excitation is calculated according to the eccentricity of the hub motor, the relative distance between the stator and the rotor when the hub motor is not eccentric, and the angular position of the rotor. 3. The vehicle vertical vibration control method according to claim 2, wherein the eccentricity of the in-wheel motor is calculated according to the following formula: ε=r/δ ₀ Wherein, ε is the eccentricity of the hub motor, r is the eccentricity of the stator and rotor, and _δ0 is the relative distance between the stator and rotor when the hub motor is not eccentric. 4. The vehicle vertical vibration control method according to claim 3, wherein the motor excitation is calculated according to the following formula:

Wherein, F is the excitation of the motor, k _μ is the saturation coefficient of the magnetic circuit, k _en is the equivalent electromagnetic stiffness, and θ _r is the angular position of the rotor. 5 . The vehicle vertical vibration control method according to claim 1 , wherein the magnetorheological damper is controlled using a hyperbolic tangent model. 6. The vehicle vertical vibration control method according to claim 5, characterized in that, determining the damping force of the magneto-rheological damper according to the moving speed of the vehicle body and the moving speed of the wheels, specifically comprising: calculating the relative speed of the suspension system according to the moving speed of the vehicle body and the moving speed of the wheels; If the moving speed of the vehicle body is in the same direction as the moving speed of the wheels and the relative speed of the suspension system is negative, the damping force of the magneto-rheological damper is determined as the first damping force, otherwise the magnetic rheological damper is determined as the first damping force. The damping force of the rheological damper is determined as a second damping force, wherein the second damping force is greater than the first damping force. 7. The vehicle vertical vibration control method according to claim 6, further comprising: When the movement speed of the vehicle body, the movement speed of the wheels and the relative speed of the suspension system change presetly, the switching of the damping force is delayed or advanced according to the requirements for ride comfort and wheel dynamic load. 8. The method for controlling vertical vibration of a vehicle according to claim 7, wherein the preset change comprises: The direction of the moving speed of the vehicle body is always upward, while the relative moving speed of the suspension system changes from positive to negative; The direction of the moving speed of the vehicle body changes from up to down, while the relative moving speed of the suspension system is always negative. 9. A vehicle vertical vibration control device, characterized in that the vehicle is driven by an in-wheel motor and the suspension system of the vehicle adopts a magneto-rheological damper, and the device comprises: A first acquisition module, the first acquisition module is used to acquire the angular position of the rotor of the in-wheel motor and the eccentricity of the stator and rotor; a calculation module, the calculation module is used to calculate the motor excitation of the hub motor according to the angular position of the rotor and the eccentricity of the stator and rotor; A second acquisition module, the second acquisition module is used to acquire the body movement speed and wheel movement speed of the vehicle; A determining module, configured to determine the damping force of the magneto-rheological damper according to the moving speed of the vehicle body and the moving speed of the wheels; A control module, the control module is used to control the in-wheel motor with the motor excitation, and control the magneto-rheological damper with the damping force.

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