WO2020103451A1

WO2020103451A1 - Dual-motor power driving device and torque distribution control method therefor

Info

Publication number: WO2020103451A1
Application number: PCT/CN2019/093151
Authority: WO
Inventors: 李占江; 高超; 蒋元广; 李麟; 郝晓阳
Original assignee: 南京越博电驱动系统有限公司
Priority date: 2018-11-21
Filing date: 2019-06-27
Publication date: 2020-05-28
Also published as: CN109484163B; CN109484163A

Abstract

A dual-motor power driving device and a torque distribution control method therefor. The power driving device comprises a dual-planet row (17), a main motor (1), an auxiliary motor (2), a main input shaft (3), an auxiliary input shaft (4), an output shaft (5) and several clutches. The main motor (1) is connected to the dual-planet row (17) by means of the main input shaft (3), and the auxiliary motor (2) is connected to the dual-planet row (17) by means of the auxiliary input shaft (4). The dual-planet row (17) employs a Simpson-type structure. The present power driving device-based torque distribution control method adjusts the working point of the motor and reasonably performs energy management according to the required power of a vehicle. At the same time, the present method may achieve single-motor braking energy recovery and dual-motor braking energy recovery under different braking forces.

Description

A dual-motor power drive device and its torque distribution control method

Technical field

The invention relates to the technical field of electric vehicles, in particular to a dual-motor power drive device and a torque distribution control method thereof.

Background technique

As the global energy crisis intensifies and the general awareness of environmental protection increases, pure electric vehicles have broad development prospects as zero-emission vehicles. However, due to factors such as cruising range and vehicle price, pure electric vehicles still face huge challenges in actual promotion.

In order to improve the cruising range of the vehicle, the present invention adopts a dual-motor single-shaft drive system. According to different working conditions of the vehicle, the main motor can be independently driven, the auxiliary motor can be independently driven, the dual-motor speed coupled drive and the dual-motor torque coupled drive can be selected to achieve vehicle efficiency Quick start and accelerated performance.

For example, the Chinese invention patent application with application number 201711024843.5 discloses a dual-motor single planetary gear train electric drive device, including a first drive motor (16), a planetary gear train (100), a second drive motor (13) and Wet clutch (104), planetary gear train (100) includes sun gear (101), ring gear (102), planet carrier (103) and planetary gear train shell, first drive motor (16) and sun gear (101) Connected, the ring gear (102) is fixedly connected to the planetary gear housing, the second drive motor (13) is connected to the planet carrier (103), and one end of the wet clutch (104) is connected to the sun gear (101) The other end is connected to the planet carrier (103).

As another example, the Chinese utility model patent with application number 201720457851.8 discloses a dual-motor drive device, including a support plate, a reinforcement plate, a motor fixing plate, a drive spindle, a lift support plate, a sun gear, a planet gear, a bearing seat, and a fixture The fixing plate, the bearing, the working shaft, and the intermediate sleeve are arranged on the motor fixing plate, a spindle bearing is arranged between the intermediate sleeve and the driving spindle, and a bearing flange is arranged on the spindle bearing, between the intermediate sleeve and the sun gear A rotating bearing is also provided; one of the planet wheels is provided with an additional motor drive gear.

The shortcomings of the above-mentioned prior art are: single-motor braking energy recovery and dual-motor braking energy recovery cannot be achieved, the operation mode is single, and the battery life of the electric vehicle cannot be effectively extended.

Summary of the invention

In view of the shortcomings of the existing technology, the present invention provides a new dual-motor power drive device and its torque distribution control method, which can adjust the working point of the motor according to the vehicle's demand power and perform reasonable energy management, and at the same time can achieve a single under different braking forces Motor braking energy recovery and dual motor braking energy recovery improve the vehicle's economy. According to the coupling characteristics of dual motors, the minimum power evaluation index is proposed as the evaluation standard for vehicle mode switching, and the working mode is adjusted according to the vehicle demand power to make the two motors work at the optimal working point, taking into account the power and economy of the vehicle.

The technical solution of the present invention is: a dual-motor power drive device, the drive device includes a double planetary row, a main motor, an auxiliary motor, a main input shaft, an auxiliary input shaft, an output shaft and a number of clutches, wherein the main motor The main input shaft is connected to the double planetary row, and the auxiliary motor is connected to the double planetary row through the auxiliary input shaft. The double planetary row adopts a Simpson structure, the seventh clutch is connected to the planetary carrier of the double planetary row, and the eighth clutch is connected to the double planetary row On the sun gear of the row, the first locker and the second locker are arranged on the ring gear of the double planetary row, and the first clutch, the second clutch, and the third clutch are arranged on the left side of the output shaft in sequence through a spline Connected to the output shaft, the first clutch, the second clutch, and the third clutch are respectively connected to the main input shaft through gear engagement, and the fourth clutch, the fifth clutch, and the sixth clutch are sequentially arranged on the left side of the output shaft and are splined with The output shaft is connected, and the fourth clutch, the fifth clutch, and the sixth clutch are respectively meshed with the auxiliary input shaft through gears.

A torque distribution control method based on the driving device of the present invention specifically includes the following steps:

Step 1, when the demand for power when the main motor work separately for P _mod1, demand for power when the auxiliary motor operation separately for P _mod2, power requirements when using the torque coupling output of the main motor and the auxiliary motor is a P _mod3, the main motor and the auxiliary motor When the speed coupling is used, the required power is P _mod4 . By calculating the required power in the four modes of the main motor and the auxiliary motor, the mode with the minimum required power is selected as the driving mode of the main motor and the auxiliary motor. Working demand power P _{Out is} calculated as formula (1):

P _Out = min (P _mod1 , P _mod2 , P _mod3 , P _mod4 ) (1)

Step 2. The required power P _{req of the} main motor or auxiliary motor is obtained from the required torque T, the required angular speed ω and the transmission efficiency η. When a single motor is independently driven, the motor torque and speed are obtained from the vehicle speed and the required torque The torque and speed of the motor and auxiliary motor are used to obtain the required power when the main motor and auxiliary motor are driven separately. The required power is as follows according to formula (2):

Step 3. When the main motor or auxiliary motor is driven by torque coupling, the lock is locked. The planetary row is used as the power coupling device. The input power of the motor is transmitted to the sun gear through the gear and ring gear and then output by the planet carrier. The relationship is decoupling, and the torque is the coupling relationship. The relationship between motor speed and motor torque is shown in formula (3) and formula (4):

n _MG1 = n _MG2 = n _s = (1 + k) n _c (3)

In formula (3) and formula (4): n _MG1 and n _MG2 are the speeds of the main and auxiliary motors respectively, T _MG1 and T _MG2 are the torques of the main and auxiliary motors respectively, and n _s is the speed of the planetary gear sun gear , N _c is the rotation speed of the planetary carrier, n _r is the rotation speed of the planetary ring gear, T _r , T _c are the torque of the planetary ring gear and the planetary carrier, k is the characteristic constant of the planetary carrier, according to the planetary carrier Structural parameters are determined.

Step 4. When the main motor or the auxiliary motor is driven by the speed coupling, the lock is separated, the planetary row is used as the power coupling device, and the input power of the motor is output by the planetary gear wheel after coupling the sun gear and the ring gear. At this time, the speed relationship is the coupling relationship. Torque is a decoupling relationship, and the relationship between motor speed and torque satisfies formula (5) and formula (6):

In formula (5) and formula (6): i _g is the speed ratio of the planetary row sun gear and the ring gear, and the meanings of other symbols are the same as those in formula (3) and formula (4).

Step 5: When the main motor and the auxiliary motor are used in the working mode at the same time, the main motor and the auxiliary motor are both working at the optimal working point while meeting the vehicle's power requirements, and the torque is calculated according to the different combinations of power coupling devices. When the torque coupling mode is used, the motor speed relationship is decoupled. The required speed is obtained according to the vehicle speed, and whether the maximum speed of the auxiliary motor is exceeded is determined according to the obtained speed. When the speed is greater than the maximum speed of the auxiliary motor, it is further determined whether the speed exceeds The maximum speed of the main motor. When the speed is greater than the maximum speed of the main motor, the torque coupling mode cannot meet the vehicle power requirements. If the maximum speed of the main motor or auxiliary motor needs to be met, the corresponding clutch is controlled to adjust the main motor in the load characteristic field of the motor. The output torque of the motor and the auxiliary motor traverses the working position of each motor that meets the relationship in the calculated characteristic field to ensure that the total required power is minimum. The output torque of the two motors is shown in formula (7):

T _reqt = T ₁ + T ₂ (7)

In formula (7), _Treqt is the vehicle demand torque, T _{1 is the} main motor torque, and T ₂ is the auxiliary motor torque.

The beneficial effects of the dual-motor power drive device and the torque distribution control method of the present invention are: in order to speed up the corresponding process in the vehicle control process, the corresponding power and motor speed in each mode are calculated according to the characteristics of the main motor and the auxiliary motor , Torque, and store the data in the storage unit in the form of a table. In the actual operation of the vehicle, the corresponding working mode can be quickly identified by looking up the table to improve the response speed of the vehicle.

BRIEF DESCRIPTION

The above-mentioned and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

FIG. 1 is a schematic structural view of the power drive system of the present invention.

The marks in the figure show: 1- main motor, 2- auxiliary motor, 3- main input shaft, 4- auxiliary input shaft, 5- output shaft, 6-double planetary row, 7- first clutch, 8- second clutch , 9-third clutch, 10-fourth clutch, 11-fifth clutch, 12-sixth clutch, 13-seventh clutch, 14-eighth clutch, 15-first lock, 16-second lock Stopper, 17-double planet row.

detailed description

The specific embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings of the specification.

As shown in FIG. 1, the power drive device of the present invention includes a double planetary row 17, a main motor 1, an auxiliary motor 2, a main input shaft 3, an auxiliary input shaft 4, an output shaft 5, and several clutches, wherein the main motor 1 It is connected to the double planetary row 17 through the main input shaft 3, the auxiliary motor 2 is connected to the double planetary row 17 through the auxiliary input shaft 4, the double planetary row 17 adopts a Simpson structure, and the seventh clutch 13 is connected to the planetary carrier of the double planetary row 17 , The eighth clutch 14 is connected to the sun gear of the double planetary row 17, the first lock 15 and the second locker 16 are provided on the ring gear of the double planetary row 17, the first clutch 7, the second clutch 8, The third clutch 9 is sequentially arranged on the left side of the output shaft 5 and is connected to the output shaft through a spline. The first clutch 7, the second clutch 8 and the third clutch 9 are respectively connected to the main input shaft 3 through gear engagement, and the fourth clutch 10. The fifth clutch 11 and the sixth clutch 12 are sequentially arranged on the left side of the output shaft 5 and connected to the output shaft 5 by splines. The fourth clutch 10, the fifth clutch 11, and the sixth clutch 12 are respectively connected to the auxiliary input shaft 4 Connected by gear mesh.

P _Out = min (P _mod1 , P _mod2 , P _mod3 , P _mod4 ) (1)

n _MG1 = n _MG2 = n _s = (1 + k) n _c (3)

Step 5. When the main motor and the auxiliary motor are used in the simultaneous working mode, the main motor and the auxiliary motor are operated at the optimal working point while meeting the vehicle's power requirements, and the torque is calculated according to the different combinations of power coupling devices , When the torque coupling mode is adopted, the motor speed relationship is decoupled. The required speed is obtained according to the vehicle speed, and whether the maximum speed of the auxiliary motor is exceeded is determined according to the obtained speed. When the speed is greater than the maximum speed of the auxiliary motor, the speed is further judged Exceed the maximum speed of the main motor. When the speed is greater than the maximum speed of the main motor, the torque coupling mode cannot meet the vehicle power requirements. If the maximum speed of the main motor or auxiliary motor needs to be met, the corresponding clutch is controlled to adjust in the motor load characteristic field The output torque of the main motor and auxiliary motor traverses the working position of each motor that meets the relationship in the calculated characteristic field to ensure that the total required power is minimum. The output torque of the two motors is shown in formula (7):

T _reqt = T ₁ + T ₂ (7)

The present invention is not limited to the above-mentioned embodiments, and without departing from the essence of the present invention, any modification, improvement, and replacement that can be thought of by those skilled in the art fall into the protection scope of the present invention.

Claims

A dual-motor power drive device includes dual planetary rows (17), main motor (1), auxiliary motor (2), main input shaft (3), auxiliary input shaft (4), output shaft (5) and several Clutches, characterized in that the main motor (1) is connected to the double planetary row (17) through the main input shaft (3), and the auxiliary motor (2) is connected to the double planetary row (17) through the auxiliary input shaft (4). The planetary row (17) adopts a Simpson structure, the seventh clutch (13) is connected to the planet carrier of the double planetary row (17), the eighth clutch (14) is connected to the sun gear of the double planetary row (17), the first The locking device (15) and the second locking device (16) are arranged on the ring gear of the double planetary row (17), and the first clutch (7), the second clutch (8), and the third clutch (9) are arranged in this order On the left side of the output shaft (5) and connected to the output shaft by splines, the first clutch (7), the second clutch (8), and the third clutch (9) are respectively connected to the main input shaft (3) through gear meshing , The fourth clutch (10), the fifth clutch (11), and the sixth clutch (12) are sequentially arranged on the left side of the output shaft (5) and connected to the output shaft (5) by splines, the fourth clutch (10) The fifth clutch (11) and the sixth clutch (12) are connected with the auxiliary input shaft (4) through gear meshing, respectively.
The torque distribution control method of the power drive device according to claim 1, characterized in that it specifically includes the following steps:

Step 1, when the demand for power when the main motor work separately for P mod1, demand for power when the auxiliary motor operation separately for P mod2, power requirements when using the torque coupling output of the main motor and the auxiliary motor is a P mod3, the main motor and the auxiliary motor When the speed coupling is used, the required power is P mod4 . By calculating the required power in the four modes of the main motor and the auxiliary motor, the mode with the minimum required power is selected as the driving mode of the main motor and the auxiliary motor. Working demand power P Out is calculated as formula (1):

P Out = min (P mod1 , P mod2 , P mod3 , P mod4 ) (1);

Step 2. The required power P req of the main motor or auxiliary motor is obtained from the required torque T, the required angular speed ω and the transmission efficiency η. When a single motor is independently driven, the motor torque and speed are obtained from the vehicle speed and the required torque The torque and speed of the motor and auxiliary motor are used to obtain the required power when the main motor and auxiliary motor are driven separately. The required power is as follows according to formula (2):

Step 3. When the main motor or auxiliary motor is driven by torque coupling, the lock is locked. The planetary row is used as the power coupling device. The input power of the motor is transmitted to the sun gear through the gear and ring gear and then output by the planetary carrier. The speed relationship is Decoupling, torque is a coupling relationship, the relationship between motor speed and motor torque is shown in formula (3) and formula (4):

n MG1 = n MG2 = n s = (1 + k) n c (3)

Step 4. When the main motor or auxiliary motor is driven by speed coupling, the lock is separated. The planetary row is used as the power coupling device. The input power of the motor is output from the planet carrier after the sun gear and the ring gear are coupled. The speed relationship is the coupling relationship and torque. It is a decoupling relationship. The relationship between motor speed and torque satisfies formula (5) and formula (6):

Step 5. When the main motor and the auxiliary motor are used in the simultaneous working mode, the main motor and the auxiliary motor are both operated at the optimal working point while satisfying the vehicle's power requirements, and the torque is calculated according to different combinations of power coupling devices When the torque coupling mode is adopted, the motor speed relationship is decoupled. The required speed is obtained according to the vehicle speed, and whether the maximum speed of the auxiliary motor is exceeded is determined according to the obtained speed. When the speed is greater than the maximum speed of the auxiliary motor, the speed is further determined Whether the maximum speed of the main motor is exceeded, when the speed is greater than the maximum speed of the main motor, the torque coupling mode cannot meet the vehicle power requirements, and the maximum speed of the main motor or auxiliary motor needs to be met, then the corresponding clutch is controlled to be combined in the motor load characteristic field Adjust the output torque of the main motor and the auxiliary motor, traverse each working position of the motor that meets the relationship in the calculated characteristic field to ensure that the total required power is minimum. The output torque of the main motor and the auxiliary motor is shown in formula (7):

T reqt = T 1 + T 2 (7).