阅读说明：本技术 一种商用车集成式轮毂电机及其控制方法 (Integrated hub motor of commercial vehicle and control method thereof ) 是由 冷帅 田丰福 郭其涛 于 2020-07-27 设计创作，主要内容包括：本发明公开了一种商用车集成式轮毂电机,包括：轮毂电机,其具有电机外壳；第一行星齿轮排,其包括第一太阳轮、第一内齿圈、第一行星轴和第一行星架；第二行星齿轮排,其包括第二太阳轮、第二内齿圈、第二行星排和第二行星架；轮毂,其与所述第一行星架和所述第二内齿圈可拆卸的连接,用于将旋转动力输出。本发明还公开了一种商用车集成式轮毂电机的控制方法,根据车辆行驶中的多种状态参数,改变车辆的轮毂电机输出功率和输出扭矩,提高了车辆行驶的平顺性。(The invention discloses an integrated hub motor of a commercial vehicle, which comprises: a hub motor having a motor housing; a first planetary gear train including a first sun gear, a first ring gear, a first planet shaft, and a first planet carrier; a second planetary gear row including a second sun gear, a second ring gear, a second planetary row and a second planet carrier; and the hub is detachably connected with the first planet carrier and the second inner gear ring and is used for outputting rotary power. The invention also discloses a control method of the integrated hub motor of the commercial vehicle, which changes the output power and the output torque of the hub motor of the vehicle according to various state parameters during the running of the vehicle and improves the running smoothness of the vehicle.)

1. The utility model provides a commercial car integrated form in-wheel motor which characterized in that includes:

a hub motor having a motor housing; and

a first planetary gear train including a first sun gear, a first ring gear, a first planet shaft, and a first planet carrier;

the first sun gear is fixedly sleeved on a motor shaft of the hub motor and can rotate at the same speed relative to the motor shaft, the first inner gear ring is fixedly installed in the motor shell, and the first planet shaft is fixedly connected with the first planet carrier;

a second planetary gear row including a second sun gear, a second ring gear, a second planet shaft, and a second planet carrier;

the second sun gear is rotatably supported on a motor shaft of the hub motor and can rotate in a differential mode relative to the motor shaft; the second planet carrier is connected with the first sun gear and can synchronously rotate with the first planet carrier, and the second planet shaft is fixedly connected with the second planet carrier;

and the hub is detachably connected with the first planet carrier and the second inner gear ring and is used for outputting rotary power.

2. The integrated hub motor for commercial vehicles according to claim 1, further comprising:

the rotor bracket is arranged in the motor shell and coaxially and fixedly sleeved on the motor shaft;

the permanent magnets are uniformly arranged on the outer side of the rotor bracket in the circumferential direction;

and the motor windings are uniformly arranged on the inner side wall surface of the motor shell in the circumferential direction, correspond to the permanent magnets and are used for driving the rotor support to rotate.

3. The integrated hub motor for commercial vehicles according to claim 2, further comprising:

a plurality of tapered rollers respectively disposed between the motor housing, the first carrier, the hub, and the motor shaft.

4. The integrated hub motor for commercial vehicles according to claim 3, further comprising:

at least one first planet wheel supported on the first planet shaft by a first needle roller, and the first needle roller is stopped by a first stopper;

at least one second planet wheel, which is supported on the second planet shaft by a second needle roller, and the second needle roller is limited by a second stop.

5. The integrated hub motor for commercial vehicles according to claim 4, further comprising:

the brake disc is coaxially and fixedly arranged on one side of the motor shaft far away from the hub;

a brake caliper axially movable relative to the brake disc for braking the brake disc;

and the brake caliper seat is fixedly arranged on one side of the motor shell far away from the hub and used for limiting the movement of the brake caliper.

6. A control method for an integrated hub motor of a commercial vehicle, characterized in that the integrated hub motor of a commercial vehicle according to claims 1-5 is used, comprising the following steps:

step 1, obtaining the transmission efficiency, the vehicle quality, the rolling resistance coefficient, the wheel deflection angle, the current vehicle speed, the highest vehicle speed, the air resistance coefficient and the automobile windward area of a hub motor, and obtaining the output power threshold of the hub motor according to the motor transmission efficiency, the vehicle quality, the rolling resistance coefficient, the wheel deflection angle, the current vehicle speed, the highest vehicle speed, the air resistance coefficient and the automobile windward area;

step 2, obtaining the climbing gradient of the vehicle, and obtaining a vehicle running deviation index according to the climbing gradient, the rolling resistance coefficient, the windward area of the vehicle and the air resistance coefficient of the vehicle;

and 3, acquiring the maximum power of the hub motor, the maximum torque of the hub motor, the transmission efficiency of the hub motor, the output loss rate of the hub motor, the output power threshold value of the hub motor and the vehicle running deviation index, and controlling the output power of the hub motor and the output torque of the hub motor according to the maximum power of the hub motor, the maximum torque of the hub motor, the transmission efficiency of the hub motor, the output loss rate of the hub motor, the output power threshold value of the hub motor and the vehicle running deviation index.

7. The control method of the integrated hub motor of the commercial vehicle according to claim 6, wherein the output power threshold of the hub motor is as follows:

in the formula, P_valIs the threshold value of the output power of the motor, eta is the transmission efficiency of the motor, m is the mass of the vehicle, g is the gravity of the object, f is the rolling resistance coefficient,

8. The control method of the integrated hub motor of the commercial vehicle according to claim 6, wherein the vehicle driving deviation positive index is:

in the formula I_subIs the vehicle running deviation index, alpha is the climbing gradient, alpha_maxIs the maximum climbing gradient.

9. The control method of an integrated hub motor for a commercial vehicle according to claim 6, wherein the maximum power of the hub motor satisfies:

P_max≥[P_e，P_a，P_c]；

in the formula, P_maxIs the maximum power of the in-wheel motor, P_eAt maximum vehicle speed power, P_aFor maximum climbing power, P_cTo accelerate the time power, V_maxAt the maximum vehicle speed, V_iSpeed of the vehicle during climbing, t is acceleration time, V_aThe vehicle speed during acceleration is the conversion coefficient of the rotating mass;

the maximum torque of the hub motor meets the following requirements:

in the formula, T_maxMaximum torque of the in-wheel motor, V_jAs the vehicle speed, i_maxFor the transmission ratio, r is the rolling radius of the wheel.

10. The control method of an integrated hub motor for a commercial vehicle according to claim 6, wherein in the step 3, the output power of the hub motor and the output torque of the hub motor are controlled through a BP neural network, comprising the steps of:

step 1, acquiring power P of the hub motor, torque T of the hub motor, transmission efficiency eta of the hub motor, output loss rate mu of the hub motor and output power threshold P of the hub motor according to a sampling period_valAnd vehicle running bias positive index I_sub；

Step 2, normalizing the acquired parameters in turn,determining input layer vector x ═ { x) for a three-layer BP neural network₁,x₂,x₃,x₄,x₅,x₆}; wherein x is₁For power, x, of the in-wheel motor₂For the torque, x, of the in-wheel motor₃For the transmission efficiency, x, of the in-wheel motor₄For the output loss rate x of the hub motor₅For the output power threshold of the in-wheel motor and x₆The vehicle running deviation index is a vehicle running deviation index;

and 3, mapping the input layer vector to an intermediate layer, wherein the intermediate layer vector y is { y ═ y₁,y₂,…,y_m}; m is the number of intermediate layer nodes;

and 4, obtaining an output layer vector o ═ o₁,o₂}；o₁For the output power o of the in-wheel motor₂Is the output torque of the hub motor;

step 5, controlling the output power of the hub motor and the output torque of the hub motor to ensure that

Wherein the content of the first and second substances,and

Technical Field

The invention relates to the technical field of hub motors, in particular to an integrated hub motor of a commercial vehicle and a control method thereof.

Background

The electric automobile is one of main development directions of automobile industry, has the characteristics of energy conservation, emission reduction and low noise, various automobile factories produce various products in quantity, the power system of each automobile factory is in a central centralized driving type, the original engine assembly is replaced by a motor, and the technology of integrating power, transmission and braking functions and directly driving a hub motor in a wheel is the most potential development direction, so that parts such as a speed reducer, a differential mechanism, a transmission shaft and the like can be omitted, the light weight and the reduced servicing quality are realized, the mechanical loss is greatly reduced, and the space in the automobile is saved.

At present, large-scale mining automobiles are generally driven by electric wheels, the structure of the mining automobiles is a scheme of combining a motor and a speed reducer, but the mining automobiles are special for mining occasions, no special requirement is provided for a motor body, and the motor in the mining automobiles is only a traditional industrial motor. The electric cars for civil use are classified into electric cars and electric coaches, the electric cars generally adopt direct-drive electric wheels, the electric coaches adopt a mode of combining a motor and a wheel-side reducer, the direct-drive electric wheels adopt low-speed outer rotor motors, and the wheel-side reducer electric wheels adopt high-speed inner rotor motors. Generally speaking, the torque of the high-speed inner rotor motor is small, and the dynamic property of the automobile driven by the method is insufficient, so that the high-speed inner rotor motor is often provided with a wheel-side speed reducer to reduce the speed and increase the torque of the output of the motor, and the dynamic property of the whole automobile is improved on the premise that the output power is basically unchanged. However, when the high-speed inner rotor motor belt wheel reduction gear is adopted, the problems of complex structure, large occupied space, overlarge overall mass and the like are often caused, and finally, the problems of sudden increase of unsprung mass and the like are caused to influence the installation and the use of the final electric wheel on the whole vehicle.

The power of a motor which is developed in the prior electric vehicle and is driven in a centralized manner is about 80KW, the maximum torque of the motor is about 400N.m, but the motors adopted in the prior electric vehicle are all traditional motors with smaller diameter and higher rotating speed, and when the output power and the output torque of the motors are adjusted, the driving state of the vehicle is generally only considered, and the self condition, the road surface and the environmental condition of the vehicle are not considered. The output power and the output torque of the motor cannot be changed at the first time when the running state of the vehicle is changed, and the fluency of power output to the wheel end is influenced.

Disclosure of Invention

The invention aims to design and develop an integrated hub motor of a commercial vehicle, which realizes speed reduction and torque increase through the power output by the hub motor under the action of a two-stage planetary gear speed reducing mechanism, and has compact structure while ensuring sufficient speed reduction ratio.

The invention also aims to design and develop a control method of the integrated hub motor of the commercial vehicle, which determines the output torque and the output power of the hub motor based on the BP neural network according to a plurality of state parameters when the vehicle runs, thereby meeting the requirement of adjusting the state of the motor at any time when the vehicle runs and improving the running smoothness of the vehicle.

The technical scheme provided by the invention is as follows:

an integrated hub motor for a commercial vehicle, comprising:

a hub motor having a motor housing; and

a first planetary gear train including a first sun gear, a first ring gear, a first planet shaft, and a first planet carrier;

the first sun gear is fixedly sleeved on a motor shaft of the hub motor and can rotate at the same speed relative to the motor shaft, the first inner gear ring is fixedly installed in the motor shell, and the first planet shaft is fixedly connected with the first planet carrier;

a second planetary gear row including a second sun gear, a second ring gear, a second planet shaft, and a second planet carrier;

the second sun gear is rotatably supported on a motor shaft of the hub motor and can rotate in a differential mode relative to the motor shaft; the second planet carrier is connected with the first sun gear and can synchronously rotate with the first planet carrier, and the second planet shaft is fixedly connected with the second planet carrier;

and the hub is detachably connected with the first planet carrier and the second inner gear ring and is used for outputting rotary power.

Preferably, the method further comprises the following steps:

the rotor bracket is arranged in the motor shell and coaxially and fixedly sleeved on the motor shaft;

the permanent magnets are uniformly arranged on the outer side of the rotor bracket in the circumferential direction;

and the motor windings are uniformly arranged on the inner side wall surface of the motor shell in the circumferential direction, correspond to the permanent magnets and are used for driving the rotor support to rotate.

Preferably, the method further comprises the following steps:

a plurality of tapered rollers respectively disposed between the motor housing, the first carrier, the hub, and the motor shaft.

Preferably, the method further comprises the following steps:

at least one first planet wheel supported on the first planet shaft by a first needle roller, and the first needle roller is stopped by a first stopper;

at least one second planet wheel, which is supported on the second planet shaft by a second needle roller, and the second needle roller is limited by a second stop.

Preferably, the method further comprises the following steps:

the brake disc is coaxially and fixedly arranged on one side of the motor shaft far away from the hub;

a brake caliper axially movable relative to the brake disc for braking the brake disc;

and the brake caliper seat is fixedly arranged on one side of the motor shell far away from the hub and used for limiting the movement of the brake caliper.

A control method of an integrated hub motor of a commercial vehicle comprises the following steps:

step 1, obtaining the transmission efficiency, the vehicle quality, the rolling resistance coefficient, the wheel deflection angle, the current vehicle speed, the highest vehicle speed, the air resistance coefficient and the automobile windward area of a hub motor, and obtaining the output power threshold of the hub motor according to the motor transmission efficiency, the vehicle quality, the rolling resistance coefficient, the wheel deflection angle, the current vehicle speed, the highest vehicle speed, the air resistance coefficient and the automobile windward area;

step 2, obtaining the climbing gradient of the vehicle, and obtaining a vehicle running deviation index according to the climbing gradient, the rolling resistance coefficient, the windward area of the vehicle and the air resistance coefficient of the vehicle;

and 3, acquiring the maximum power of the hub motor, the maximum torque of the hub motor, the transmission efficiency of the hub motor, the output loss rate of the hub motor, the output power threshold value of the hub motor and the vehicle running deviation index, and controlling the output power of the hub motor and the output torque of the hub motor according to the maximum power of the hub motor, the maximum torque of the hub motor, the transmission efficiency of the hub motor, the output loss rate of the hub motor, the output power threshold value of the hub motor and the vehicle running deviation index.

Preferably, the threshold value of the output power of the in-wheel motor is as follows:

in the formula, P_valIs the threshold value of the output power of the motor, eta is the transmission efficiency of the motor, m is the mass of the vehicle, g is the gravity of the object, f is the rolling resistance coefficient,for the inside wheel deflection angle,

for the outboard wheel deflection angle, omega is the adjustment coefficient, V_jFor the current vehicle speed, V_maxAt the maximum vehicle speed, C_DIs the air resistance coefficient, and A is the frontal area of the automobile.

Preferably, the vehicle driving bias positive index is:

in the formula I_subIs the vehicle running deviation index, alpha is the climbing gradient, alpha_maxIs the maximum climbing gradient.

Preferably, the maximum power of the in-wheel motor satisfies:

P_max≥[P_e，P_a，P_c]；

in the formula, P_maxIs the maximum power of the in-wheel motor, P_eAt maximum vehicle speed power, P_aFor maximum climbing power, P_cTo accelerate the time power, V_maxAt the maximum vehicle speed, V_iSpeed of the vehicle during climbing, t is acceleration time, V_aThe vehicle speed during acceleration is the conversion coefficient of the rotating mass;

the maximum torque of the hub motor meets the following requirements:

in the formula, T_maxMaximum torque of the in-wheel motor, V_jAs the vehicle speed, i_maxFor the transmission ratio, r is the rolling radius of the wheel.

Preferably, in step 3, the controlling the output power of the in-wheel motor and the output torque of the in-wheel motor by the BP neural network includes the following steps:

step 1, acquiring power P of the hub motor, torque T of the hub motor, transmission efficiency eta of the hub motor, output loss rate mu of the hub motor and output power threshold P of the hub motor according to a sampling period_valAnd vehicle running bias positive index I_sub；

Step 2, normalizing the acquired parameters in sequence, and determining an input layer vector x ═ x of the three-layer BP neural network₁，x₂，x₃，x₄，x₅，x₆}; wherein x is₁For power, x, of the in-wheel motor₂For the torque, x, of the in-wheel motor₃For the transmission efficiency, x, of the in-wheel motor₄For the output loss rate x of the hub motor₅For the output power threshold of the in-wheel motor and x₆The vehicle running deviation index is a vehicle running deviation index;

and 3, mapping the input layer vector to an intermediate layer, wherein the intermediate layer vector y is { y ═ y₁，y₂，…，y_m}; m is the number of intermediate layer nodes;

and 4, obtaining an output layer vector o ═ o₁，o₂}；o₁For the output power o of the in-wheel motor₂Is the output torque of the hub motor;

step 5, controlling the output power of the hub motor and the output torque of the hub motor to ensure that

Wherein the content of the first and second substances,

andoutput layer vector parameters, P, for the ith sampling period_{1_max}Is the maximum output power, T, of the in-wheel motor_{1_max}Is the maximum output torque, P, of the in-wheel motor_{1_(i+1)}And T_{1_(i+1)}The output power and the output torque of the (i + 1) th in-wheel motor are respectively.

The invention has the following beneficial effects:

according to the integrated hub motor for the commercial vehicle, the hub motor and the two-stage planetary gear speed reducing mechanism are integrated to realize the speed reducing and torque increasing effects of the high-speed inner rotor type electric wheel, and the problems that the hub motor is insufficient in driving torque and is difficult to apply to a large heavy-load vehicle are solved; the integrated electric wheel realizes compact and reasonable structure height and reduces the arrangement space.

According to the control method of the integrated hub motor of the commercial vehicle, provided by the invention, the output torque and the output power of the hub motor are determined based on the BP neural network according to a plurality of state parameters when the vehicle runs, so that the condition of the motor can be adjusted at any time when the vehicle runs, and the running smoothness of the vehicle is improved.

Drawings

Fig. 1 is a cross-sectional view showing the internal structure of an integrated hub motor for a commercial vehicle according to the present invention.

Fig. 2 is a sectional view showing an internal structure of the motor according to the present invention.

Fig. 3 is a schematic structural view of a motor shaft according to the present invention.

Fig. 4 is a schematic structural diagram of the motor according to the present invention.

Detailed Description

The present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text.

As shown in figure 1, the hub motor of the invention adopts a high-speed inner rotor structure, and then a two-stage planetary gear speed reducing mechanism is connected at the output end of the motor rotor, namely the motor shaft, and the speed reducing mechanism is used for reducing the speed and increasing the torque of the output of the motor.

As shown in fig. 1 and 2, the overall structure of the present invention is schematically illustrated, and includes: the wheel rim comprises a wheel rim 1, a right motor shell 2, a left motor shell 3, a motor winding 4, a rotor support 5, a rotor reinforcing rib 6, a J-shaped frameless rubber oil seal 7, a first elastic retainer ring 8, a first tapered roller bearing 9, a stop washer 10 for a first round nut, a first round nut 11, a motor shaft 12, a brake disc 13, a labyrinth seal disc 14, a labyrinth seal nut 15, a stop washer 16 for a second round nut, a friction plate 17, an oil cylinder 18, a brake caliper 19, a hexagonal bolt 20, a first double-headed stud 21, a first elastic washer 22, an inner hexagonal cylindrical head screw 23, a second tapered roller bearing 24, a motor shell reinforcing rib 25, a first right-end planet carrier 26, a first hexagonal nut 27, a sealing ring 28, a wheel rim bolt 29, a second inner gear ring 30, a second elastic washer 31, a second hexagonal nut 32, a second double-headed stud 33, a second planet wheel 34, a second planet shaft 35, a first outer ring 27, a first, The bearing cover plate 36, the second sun gear 37, the third conical roller bearing 38, the third elastic washer 39, the hexagon socket head bolt 40, the sealing gasket 41, the stopper washer 42 for the third round nut, the second round nut 43, the sealing cover plate 44, the second elastic retainer 45, the fourth elastic washer 46, the second right-end carrier 47, the first centripetal needle roller 48, the first L-shaped stopper 49, the second left-end carrier 50, the pin 51, the first sun gear 52, the first planetary shaft 53, the first planetary gear 54, the first ring gear 55, the second centripetal needle roller 56, the second L-shaped stopper 57, the first left-end carrier 58, the third elastic retainer 59, the caliper holder 60, and the permanent magnet 61.

As shown in fig. 2 and 3, the hub motor of the present invention is composed of a left motor housing 3, a right motor housing 2, a rotor support 5, and a motor shaft 12; wherein, the rotor bracket 5 is connected with the motor shaft 12 through a first elastic washer 22 and an inner hexagonal socket head cap screw 23; the left motor shell 3 is inwards sunken to form a concave cavity so as to integrate the brake; the labyrinth seal disc 14 is connected with the left motor shell 3 through an inner hexagon bolt 20, and the left motor shell 3 and the motor shaft 12 are sealed through a labyrinth seal device formed by the labyrinth seal disc 14, a labyrinth seal round nut 15 and a stop washer 16 for a second round nut; the right motor shell 2 is sunken inwards to form a concave cavity so as to integrate a two-stage planetary gear speed reducing mechanism, and the right motor shell 2 is supported on the motor shaft 12 through a second tapered roller bearing 24; the left motor shell 3 and the right motor shell 2 are connected through a first stud 21; a J-shaped frameless rubber oil seal 7 and a first elastic retainer ring 8 are arranged among the right motor shell 2, the first tapered roller bearing 9 and the motor shaft 12 for sealing; the left motor shell 3 is supported on a motor shaft 12 through a first tapered roller bearing 9; the first tapered roller bearing 9 is pre-tightened and limited by a stop washer 42 and a second round nut 43 through a third round nut, a rotor reinforcing rib 6 is arranged between the rotor bracket 5 and the left motor casing 3 and the right motor casing 2, and a motor casing reinforcing rib 25 is arranged in the cavity of the left motor casing 3 and the cavity of the right motor casing 2.

The hub motor structure also comprises a motor winding 4 and a permanent magnet; wherein, the motor winding 4 is pasted on the right motor shell 2, and the permanent magnet is fixed on the rotor bracket 5.

As shown in fig. 1, the integrated in-wheel motor of the present invention further includes a brake disc 13, a brake caliper 19, and a brake caliper seat 60, and adopts a floating caliper disc brake; the brake disc 13 is fixed on the motor shaft 12 through an involute spline connection, and is axially positioned through a first round nut, a stop washer 10, a first round nut 11 and a shaft shoulder on the motor shaft 12; the brake caliper 19 can move left and right in the brake caliper seat 60, friction plates 17 are arranged on two sides of the brake caliper 19, an oil cylinder 18 is connected to the friction plate 17 far away from one side of the brake disc 13 and used for pushing the friction plate 17 to move for braking, and the brake caliper seat 60 is fixed on the shell of the left motor shell 2 through bolt connection. The floating caliper disc brake used in this embodiment is a common brake in the prior art, and therefore, the specific structure and the working principle thereof are not described herein again.

The two-stage planetary gear speed reducing mechanism consists of a first planetary gear row and a second planetary gear row; the first planetary gear row of the invention is composed of a first sun gear 52, a first planetary gear 54, a first left end planet carrier 58, a first right end planet carrier 26, a first internal gear 55 and a first planet shaft 53; the first sun gear 52 is fixedly sleeved on the motor shaft 12 and rotates synchronously with the motor shaft 12, the first left-end planet carrier 58 is sleeved at one end of the first planet shaft 53 and is clamped and limited by the shaft elastic check ring 42; the first left-end planet carrier 58 is supported on the motor shaft 12 through a third circlip 59 and a third conical roller bearing 38; the first right planet carrier 26 is sleeved at the other end of the first planet shaft 53; a sealing ring 28 is arranged between the first right planet carrier 26 and the first inner gear ring 55, the first right planet carrier 26 is detachably fixed on a wheel hub through a first hexagon nut 27 and a wheel rim bolt 29, and the wheel hub is fixed on the wheel rim 1 through a bolt; the main body of the first ring gear 55 is press-fitted into the cavity of the right motor case 2, and the first ring gear 55 is fixed with the right motor case 2.

The second planetary gear row of the invention is composed of a second sun gear 37, a second planet gear 34, a second right-end planet carrier 47, a second left-end planet carrier 50, a second ring gear 30 and a second planet shaft 35; the main body of the second sun gear 37 is sleeved on the motor shaft 12 in an empty way and rotates with the motor shaft 12 in a differential speed way, and the second sun gear 37 is limited by a second elastic retainer ring 45 for the shaft, so that the second sun gear 37 is prevented from moving in an axial direction;

a second right planet carrier 47 is sleeved at one end of the second planet shaft 35 and is clamped and limited by a fourth elastic washer 46 for shaft; the second left planet carrier 50 is sleeved at the other end of the second planet shaft 35, and the second left planet carrier 50 is fixedly connected with the first sun gear 52 through a pin 51, so that the first sun gear 52 and the second left planet carrier 50 rotate synchronously; the second ring gear 30 is connected with the bearing cover plate 36 and the first right planet carrier 26 through a second elastic washer 31, a second hexagon nut 32 and a second stud 33; the bearing cover plate 36 and the sealing cover plate 44 are sealed by a third elastic washer 39, a hexagon socket head bolt 40 and a sealing gasket 41.

In another embodiment, the first planetary gear row structure further comprises: a second centering needle roller 56, a second L-shaped stopper 57; wherein the first planet 54 is supported on the first planet shaft 53 by means of the second centripetal needle roller 56; the left and right ends of the second centering roller pin 56 are respectively limited by a second L-shaped stop 57.

In another embodiment, the second planetary gear row structure further includes: a first centripetal needle roller 48 and a first L-shaped stop 49; the second planet wheel 34 is supported on the second planet shaft 35 through a first centripetal needle roller 48, and the left end and the right end of the second planet wheel are limited by a first L-shaped stop block 49 respectively.

As shown in fig. 1, the power output from the motor rotor support 50 is transmitted to the first sun gear 52 and then to the first planet gears 54 via the motor shaft 12, so that the power is transmitted from the first sun gear 52 to the second sun gear 37 sleeved thereon and then to the second planet gears 34 via the second planet shaft 35, and because the first right-end planet carrier 26 and the first ring gear 55 are fixed to the right motor casing 2 and are stationary, the power is directly transmitted to the second ring gear 30 via the second planet gears 34 and finally transmitted to the wheels via the hubs.

As shown in fig. 4, in another embodiment, the in-wheel motor is an inner rotor permanent magnet synchronous motor, the rotor core 120 of the motor has an outer diameter of 272mm, an inner diameter of 132mm, a magnet thickness of 6.94mm, a magnet width of 27.7mm, and the stator core 110 of the motor has an outer diameter of 500mm and an inner diameter of 273mm, wherein the depth of the slot of the tooth portion 130 is 75.8mm, the width of the opening of the slot is 12mm, the width of the slot is 75.9mm, the angle of the tooth shoe is 15 degrees, the thickness of the tooth is 6.73mm, and the radius of the top fillet is 5.56; the motor stator windings are connected in a star shape, sine waves are used for driving, and coil wiring is in an up-down overlapping method; the slot insulation thickness is 1.11mm, the coil interlayer insulation thickness is 1.11mm, the slot wedge thickness is 2.22mm, the coil filling coefficient is 40%, the winding coefficient is 93.3%,

according to the integrated hub motor of the commercial vehicle, the hub motor and the two-stage planetary gear speed reducing mechanism are integrated to realize the speed reducing and torque increasing effects of the high-speed inner rotor type electric wheel, and the problems that the hub motor is insufficient in driving torque and is difficult to apply to large heavy-duty vehicles are solved; the integrated electric wheel has the advantages that the structure is compact and reasonable, the arrangement space is reduced, the sealing device is additionally arranged, the sealing problem among the motor, the motor and the speed reducer and between the speed reducer and the wheel hub is solved, the electric wheel device is fully lubricated, the mechanical abrasion is greatly reduced, the transmission efficiency is improved, and meanwhile, the service life of the electric wheel device is greatly prolonged.

The invention provides a control method of an integrated hub motor of a commercial vehicle, which uses the integrated hub motor of the commercial vehicle and comprises the following steps:

step 1, obtaining the transmission efficiency, the vehicle quality, the rolling resistance coefficient, the wheel deflection angle, the current vehicle speed, the highest vehicle speed, the air resistance coefficient and the automobile windward area of a hub motor, and obtaining the output power threshold of the hub motor according to the motor transmission efficiency, the vehicle quality, the rolling resistance coefficient, the wheel deflection angle, the current vehicle speed, the highest vehicle speed, the air resistance coefficient and the automobile windward area;

wherein, the hub motor output power threshold is:

in the formula, P_valFor outputting work to the motorA rate threshold, eta is the transmission efficiency of the motor, m is the mass of the vehicle, g is the gravity of the object, f is the rolling resistance coefficient,for the inside wheel deflection angle,

for the outboard wheel deflection angle, omega is the adjustment coefficient, V_jFor the current vehicle speed, V_maxAt the maximum vehicle speed, C_DIs the air resistance coefficient, and A is the frontal area of the automobile.

Step 2, obtaining the climbing gradient of the vehicle, and obtaining a vehicle running deviation index according to the climbing gradient, the rolling resistance coefficient, the windward area of the vehicle and the air resistance coefficient of the vehicle;

wherein the vehicle driving bias positive index is as follows:

in the formula I_subIs the vehicle running deviation index, alpha is the climbing gradient, alpha_maxIs the maximum climbing gradient.

The maximum power of the hub motor meets the following requirements:

P_max≥[P_e，P_a，P_c]；

in the formula, P_maxIs the maximum power of the in-wheel motor, P_eAt maximum vehicle speed power, P_aFor maximum climbing power, P_cTo accelerate time power，V_maxAt the maximum vehicle speed, V_iSpeed of the vehicle during climbing, t is acceleration time, V_aThe vehicle speed during acceleration is the conversion coefficient of the rotating mass;

the maximum torque of the hub motor meets the following requirements:

in the formula, T_maxMaximum torque of the in-wheel motor, V_jAs the vehicle speed, i_maxFor the transmission ratio, r is the rolling radius of the wheel.

And 3, acquiring the maximum power of the hub motor, the maximum torque of the hub motor, the transmission efficiency of the hub motor, the output loss rate of the hub motor, the output power threshold value of the hub motor and the vehicle running deviation index, and controlling the output power of the hub motor and the output torque of the hub motor according to the maximum power of the hub motor, the maximum torque of the hub motor, the transmission efficiency of the hub motor, the output loss rate of the hub motor, the output power threshold value of the hub motor and the vehicle running deviation index.

In another embodiment, in step 3, controlling the output power of the engine and the battery through the BP neural network includes the following steps:

step 1, establishing a neural network.

The BP network system structure adopted by the invention is composed of three layers, the first layer is an input layer, n nodes are provided in total, n signals representing the working state of the equipment are correspondingly provided, and the signal parameters are provided by a data preprocessing module in a control system. The second layer is a hidden layer, and has m nodes, and is determined by the training process of the network in a self-adaptive mode. The third layer is an output layer, p nodes are provided in total, and the output is determined by the response actually needed by the system.

The mathematical model of the network is:

inputting a vector: x ═ x₁，x₂，...，x_n)^T

Intermediate layer vector: y ═ y₁，y₂，...，y_m)^T

Outputting a vector: o ═ o (o)₁，o₂，...，o_p)^T

In the invention, the number of nodes of the input layer is n-6, and the number of nodes of the output layer is P-2. The number m of hidden layer nodes is estimated by the following formula:

according to the sampling period, obtaining the power P of the hub motor, the torque T of the hub motor, the transmission efficiency eta of the hub motor, the output loss rate mu of the hub motor and the output power threshold P of the hub motor_valAnd vehicle running bias positive index I_subAs input parameters; the input parameters belong to different physical quantities, and the dimensions of the input parameters are different. Therefore, the data needs to be normalized to a number between 0-1 before it is input into the artificial neural network.

Determining input layer vector x ═ { x) for a three-layer BP neural network₁，x₂，x₃，x₄，x₅，x₆}; wherein x is₁For power, x, of the in-wheel motor₂For the torque, x, of the in-wheel motor₃For the transmission efficiency, x, of the in-wheel motor₄For the output loss rate x of the hub motor₅For the output power threshold of the in-wheel motor and x₆The vehicle running deviation index is a vehicle running deviation index;

specifically, the power P of the in-wheel motor is normalized to obtain the power coefficient x of the in-wheel motor₁，

Wherein, P_minAnd P_maxRespectively the minimum power and the maximum power of the hub motor.

Normalizing the torque T of the in-wheel motor to obtain the torque coefficient x of the in-wheel motor₂；

Wherein, T_minAnd T_maxRespectively the minimum torque and the maximum torque of the in-wheel motor.

Normalizing the transmission efficiency eta of the in-wheel motor to obtain the transmission efficiency coefficient x of the in-wheel motor₃；

Wherein eta is_minAnd η_maxThe minimum value and the maximum value of the transmission efficiency of the hub motor are respectively.

Normalizing the output loss rate mu of the hub motor to obtain the output loss rate coefficient x of the hub motor₄；

Wherein, mu_minAnd mu_maxThe minimum value and the maximum value of the output loss rate of the hub motor are respectively.

Obtain the output layer vector o ═ o₁，o₂}；o₁For the output power o of the in-wheel motor₂Is the output torque of the hub motor.

o₁And the ratio of the output power of the hub motor in the next sampling period to the maximum value of the output power of the hub motor in the current sampling period is shown. That is, in the ith sampling period, the output power P of the in-wheel motor is acquired_1-iOutputting the output power regulation coefficient of the hub motor of the ith sampling period through a BP neural networkThen, controlling the output power of the in-wheel motor in the (i + 1) th sampling period to be P_{1_(i+1)}So that it satisfies:

o₂and the ratio of the output torque of the hub motor in the next sampling period to the maximum value of the output torque of the hub motor in the current sampling period is represented. That is, in the ith sampling period, the output torque P of the in-wheel motor is acquired_2-iOutputting the output torque adjusting coefficient of the hub motor of the ith sampling period through a BP neural networkThen, controlling the output torque of the in-wheel motor in the (i + 1) th sampling period to be P_{2_(i+1)}So that it satisfies:

and 2, training the BP neural network.

After the BP neural network node model is established, the training of the BP neural network can be carried out. Obtaining training samples according to empirical data of the product, and giving a connection weight w between an input node i and a hidden layer node j_ijConnection weight w between hidden layer node j and output layer node k_jkThreshold value theta of hidden layer node j_jThreshold value w of node k of output layer_ij、w_jk、θ_j、θ_kAre all random numbers between-1 and 1.

Continuously correcting w in the training process_ijAnd w_jkUntil the system error is less than or equal to the expected error, the training process of the neural network is completed.

As shown in table 1, a set of training samples is given, along with the values of the nodes in the training process.

TABLE 1 training Process node values

And 3, acquiring data operation parameters and inputting the data operation parameters into a neural network to obtain a regulation and control coefficient.

The trained artificial neural network is solidified in the chip, so that the hardware circuit has the functions of prediction and intelligent decision making, and intelligent hardware is formed. After the intelligent hardware is powered on and started, the initial output power of the hub motor is controlled

Controlling initial output power of battery

Meanwhile, the power P of the hub motor, the torque T of the hub motor, the transmission efficiency eta of the hub motor, the output loss rate mu of the hub motor and the output power threshold P of the hub motor are obtained_valAnd vehicle running bias positive index I_subNormalizing the parameters to obtain an initial input vector of the BP neural networkObtaining an initial output vector through operation of a BP neural network

Step 4, obtaining an initial output vector

Then, the output power of the hub motor and the output torque of the hub motor can be adjusted. The output power of the hub motor and the output torque of the hub motor in the next sampling period are respectively as follows:

acquiring the power P of the hub motor, the torque T of the hub motor, the transmission efficiency eta of the hub motor, the output loss rate mu of the hub motor and the output power threshold P of the hub motor in the ith sampling period through a sensor_valAnd vehicle running bias positive index I_subAn input vector x of the ith sampling period is obtained by normalizationⁱ＝{x₁ ⁱ，x₂ ⁱ，x₃ ⁱ，x₄ ⁱ，x₄ ⁱ，x₅ ⁱObtaining an output vector of the ith sampling period through the operation of a BP neural network

Then the output power of the in-wheel motor and the output torque of the in-wheel motor are respectively as follows when the (i + 1) th sampling period is carried out:

through the arrangement, the output power of the hub motor and the output torque of the hub motor are adjusted in the running process of the automobile.

According to the control method of the integrated hub motor of the commercial vehicle, provided by the invention, the output torque and the output power of the hub motor are determined based on the BP neural network according to a plurality of state parameters when the vehicle runs, so that the condition of the motor can be adjusted at any time when the vehicle runs, and the running smoothness of the vehicle is improved.

While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable in various fields of endeavor to which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.