Electric drive system torque control method and device

Abstract

The embodiment of the application provides a kind of electric drive system torque control method and device, it is related to electric drive system control technical field, the method comprises: obtaining the working condition parameter of vehicle driving wheel;In the case where working condition parameter meets first working condition rule, determine that driving wheel is empty, and output empty flag bit;According to empty flag bit, based on first calculation rule, the expected motor torque of vehicle and the motor torque of driving wheel empty instant are calculated;Desired torque following curve is generated, and the output torque of motor is adjusted according to desired torque following curve;To optimize the motor torque output of new energy vehicle under certain working condition, to avoid the problem of electric drive system overload caused by the too large speed variation after driving wheel is empty.

Description

Technical Field

[0001] This application relates to the field of electric drive system control technology, and more specifically, to a torque control method and device for an electric drive system. Background Technology

[0002] Currently, new energy vehicles mainly use electric motors as their primary driving force. When a vehicle passes over a gentle, low-slope road with a bump, the driver's visibility is good due to the gentle slope, leading to a subjective acceleration behavior. When the vehicle passes over the bump at high speed, it will instantly lift off the ground due to the high speed. As the ground friction is lost, the drive wheel speed will increase rapidly. When the vehicle touches the ground again, it will be subjected to a large acceleration impact, causing the electric drive system to overload. Summary of the Invention

[0003] The purpose of this application is to provide a torque control method and device for an electric drive system, so as to solve the problem of overload of the electric drive system caused by excessive speed change after the drive wheels of a vehicle are off the ground.

[0004] In a first aspect, embodiments of this application provide a torque control method for an electric drive system, including:

[0005] Obtain the operating parameters of the vehicle's drive wheels;

[0006] If the operating parameters meet the first operating condition rule, determine that the drive wheels are in the air and output the air-in-air flag.

[0007] Based on the air-lift marker and the first calculation rule, the vehicle's expected motor torque and the motor torque at the moment the drive wheels are air-lifted are calculated.

[0008] Generate the desired torque following curve, and adjust the motor's output torque according to the desired torque following curve.

[0009] In the above implementation process, the operating parameters of the vehicle's drive wheels are obtained; if the operating parameters meet the first operating condition rule, it is determined that the drive wheels are airborne and an airborne flag is output; based on the airborne flag and the first calculation rule, the desired motor torque of the vehicle and the motor torque at the moment the drive wheels are airborne are calculated; a desired torque following curve is generated, and the output torque of the motor is adjusted according to the desired torque following curve; in order to optimize the motor torque output of the new energy vehicle under specific operating conditions, so as to avoid the problem of electric drive system overload caused by excessive speed change after the drive wheels are airborne.

[0010] Furthermore, obtaining the operating parameters of the vehicle's drive wheels includes:

[0011] Real-time acquisition of tire pressure changes and rotational speed changes of the vehicle's drive wheels.

[0012] In the implementation process, the tire pressure change and the rotation speed change rate of the driving wheel of the vehicle are acquired to determine whether the driving wheel of the vehicle is lifted, and only the two parameters are considered to improve the identification effectiveness.

[0013] Further, in the case where the working condition parameter satisfies the first working condition rule, it is determined that the driving wheel is lifted, and a lifting flag is output.

[0014] When the tire pressure change is not less than a first set threshold and the rotation speed change rate is not less than a second set threshold, it is determined that the driving wheel is lifted, and a lifting flag is output.

[0015] In the implementation process, if it is determined that the driving wheel is lifted, a lifting flag is output to facilitate calculation of the motor torque.

[0016] Further, according to the lifting flag, a vehicle expected motor torque and a motor torque at a lifting moment of the driving wheel are calculated based on a first calculation rule.

[0017] The driving wheel ground clearance is calculated.

[0018]

[0019] Wherein, g is the acceleration of gravity, v is the driving wheel speed at the lifting moment, and θ is the angle between the vehicle and the ground at the lifting moment.

[0020] The driving wheel lifting time is calculated.

[0021]

[0022] Wherein, h is the driving wheel ground clearance.

[0023] The driving wheel speed at a landing moment is calculated.

[0024]

[0025] Wherein, I is the moment of inertia of the entire electric drive system, M0 is the motor torque at the lifting moment of the driving wheel, i is the transmission ratio of the shaft system 1 to the shaft system n, v is the driving wheel speed at the lifting moment, and T is the driving wheel lifting time. 1n

[0026] The ground support force received by the driving wheel at the landing moment is calculated.

[0027]

[0028] Wherein, m is the mass of the vehicle.

[0029] The ground friction of the driving wheel at the landing moment is calculated.

[0030] f = μF. ​

[0031] wherein μ is the coefficient of friction of the ground;

[0032] Calculate the impact torque on the output shaft n:

[0033] M n = fr;

[0034] wherein r is the radius of the drive wheel;

[0035] Calculate the impact torque on the shaft (n-1):

[0036] M n-1 = M n i (n-1)n ;

[0037] wherein i (n-1)n is the transmission ratio between the shaft (n-1) and the shaft n;

[0038] Calculate the impact torque on the shaft 2:

[0039] M2= M n i 2n ;

[0040] wherein i 2n is the transmission ratio between the shaft 2 and the shaft n;

[0041] Calculate the impact torque on the shaft 1:

[0042] M1= M n i 1n ;

[0043] wherein i 1n is the transmission ratio between the shaft 1 and the shaft n;

[0044] Calculate the impact degree of the shaft 1:

[0045]

[0046] wherein I w1 is the moment of inertia of the shaft 1;

[0047] Calculate the impact degree of the shaft 2:

[0048]

[0049] wherein I w2 is the moment of inertia of the shaft 2;

[0050] Calculate the impact degree of the shaft (n-1):

[0051]

[0052] wherein Iwn-1 Let be the moment of inertia of the (n-1) axis system;

[0053] Calculate the impact intensity of shaft system n:

[0054]

[0055] Among them, I wn Let n be the moment of inertia of the axis system n;

[0056] Setting the impact intensity of each axle system equal to the critical safety threshold, multiple v' values ​​are calculated. The smallest v' value is taken as the desired drive wheel speed value of the vehicle.

[0057]

[0058] Where, a'1 is the impact threshold of shaft system 1, I w1 Let M1 be the moment of inertia of shaft system 1, and M1 be the impact torque acting on shaft system 1. 1n This is the transmission ratio between shaft system 1 and shaft system n;

[0059]

[0060] Where a'2 is the impact threshold of shaft system 2, I w2 Let M2 be the moment of inertia of shaft system 2, and M2 be the impact torque acting on shaft system 2. 2n This refers to the transmission ratio between shaft system 2 and shaft system n.

[0061]

[0062] Among them, a' n-1 I is the impact threshold of the shaft system (n-1). w(n-1) Let M be the moment of inertia of the shaft system (n-1). n-1 The impact torque experienced by shaft system (n-1);

[0063]

[0064] Among them, a' n I is the impact threshold of shaft system n. wn Let M be the moment of inertia of axis system n. n The impact torque experienced by shaft system n;

[0065] Calculate the vehicle's desired drive wheel speed:

[0066] v' = min(v'1, v'2, ..., v') n-1 ,v' n );

[0067] Based on the vehicle's desired drive wheel speed, the desired motor torque during the vehicle's descent is obtained:

[0068]

[0069] Among them, v' is the expected driving wheel speed, v is the driving wheel speed at the moment of takeoff, T is the driving wheel takeoff time, I is the moment of inertia of the entire electric drive system, and i 1n is the transmission ratio between shaft system 1 and shaft system n;

[0070] According to the obtained expected motor torque M of the vehicle, compare it with the motor torque M0 at the moment of driving wheel takeoff. When M < M0, the output torque is the calculated value M; when M ≥ M0, the output torque is equal to the calculated value M0.

[0071] In the above implementation process, the expected motor torque of the vehicle and the motor torque at the moment of driving wheel takeoff are calculated to output an expected torque following curve, so as to perform feedback adjustment on the motor torque. At the same time, during the process of obtaining the motor torque, the impact performance of each shaft system is considered to effectively avoid the overload problem of the electric drive system.

[0072] Further, the generation of the expected torque following curve includes:

[0073] Design a cubic torque following curve, and the obtained curve of the expected torque changing with time is:

[0074]

[0075] Among them, M0 is the motor torque at the moment of driving wheel takeoff; M is the expected motor torque of the vehicle; t1 is the start control time; t f is the end control time; (t f -t1) is the set torque adjustment time, and this time needs to be less than the driving wheel takeoff time.

[0076] In the above implementation process, an expected torque following curve is generated to perform feedback adjustment on the motor torque, convert the torque adjustment problem into an expected torque curve following problem, and the torque adjustment time can be adjusted, and the smoothness of the torque adjustment process is good.

[0077] Further, the adjustment of the output torque of the motor according to the expected torque following curve includes:

[0078] Taking the cubic torque following curve as the ideal tracking path of PID torque control, perform closed-loop feedback control on the motor torque, and adjust the output torque of the driving motor in real time so that the motor torque when the driving wheel takes off tracks the expected motor torque to protect the impact on the electric drive system within a safe range.

[0079] In the above implementation process, the output torque of the motor is adjusted and optimized according to the expected torque following curve to avoid the overload problem of the electric drive system caused by excessive speed change after the driving wheel takes off.

[0080] Secondly, embodiments of this application provide an electric drive system torque control device, comprising:

[0081] The parameter acquisition module is used to acquire the operating parameters of the vehicle's drive wheels;

[0082] The air-free determination module is used to determine whether the drive wheels are air-free when the operating parameters meet the first operating condition rule, and output an air-free flag.

[0083] The torque calculation module is used to calculate the vehicle's desired motor torque and the motor torque at the moment the drive wheels are airborne, based on the airborne marker position and the first calculation rule.

[0084] The torque adjustment module is used to generate the desired torque following curve and adjust the motor's output torque according to the desired torque following curve.

[0085] Thirdly, embodiments of this application provide an electronic device, including:

[0086] The system includes a processor, a memory, and a bus. The processor is connected to the memory via the bus. The memory stores computer-readable instructions that, when executed by the processor, are used to implement the torque control method for the electric drive system as described above.

[0087] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a server, implements the electric drive system torque control method as described above.

[0088] Fifthly, embodiments of this application provide a computer program product, the computer program product including instructions, which, when executed by a computer, cause the computer to implement the electric drive system torque control method as described above. Attached Figure Description

[0089] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0090] Figure 1 A schematic flowchart illustrating a torque control method for an electric drive system provided in an embodiment of this application;

[0091] Figure 2 A schematic diagram of a cubic torque following curve for an electric drive system torque control method provided in this application embodiment;

[0092] Figure 3 A torque implementation control block diagram for another electric drive system torque control method provided in this application embodiment;

[0093] Figure 4 This is a schematic diagram of the structure of an electric drive system torque control device provided in an embodiment of this application;

[0094] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0095] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0096] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0097] Please refer to Figure 1 , Figure 1 This is a schematic flowchart illustrating a torque control method for an electric drive system provided in an embodiment of this application. (Refer to...) Figure 1 The torque control method for the electric drive system includes:

[0098] 100. Obtain the operating parameters of the vehicle's drive wheels.

[0099] It is understandable that obtaining the operating parameters of the vehicle's drive wheels and judging the condition of the drive wheels based on these parameters is necessary to adjust the torque of the electric drive system in order to avoid overload problems caused by excessive speed changes when the drive wheels are off the ground.

[0100] Specifically, the tire pressure change and speed change rate of the vehicle's drive wheels are acquired in real time. The acquisition of the tire pressure change and speed change rate of the vehicle's drive wheels is used to determine whether the vehicle's drive wheels are in the air. At the same time, only these two parameters are considered to improve the effectiveness of the identification.

[0101] Optionally, the tire pressure change of the vehicle's drive wheels can be obtained by installing a pressure sensor inside each tire. This sensor can measure the air pressure inside the tire in real time and transmit the pressure information to a central receiver via a wireless transmitter. The central receiver processes the received data to obtain the air pressure data of each tire.

[0102] Optionally, the tire pressure change of the vehicle's drive wheels can be obtained indirectly by comparing the speed differences between different tires. When the tire pressure of a certain tire decreases, its rolling radius will decrease, resulting in a relatively faster speed. The system monitors the tire speed through wheel speed sensors and determines whether the tire pressure is normal.

[0103] Optionally, the rate of change of the vehicle's drive wheel speed can be obtained by integrating multiple sensors (including wheel speed sensors, acceleration sensors, etc.) and advanced control algorithms to monitor the vehicle's motion status in real time and intervene and adjust as necessary.

[0104] 200. If the operating parameters meet the first operating condition rule, determine that the drive wheel is in the air and output the air-in-the-air flag.

[0105] Specifically, when the tire pressure change is not less than the first set threshold and the speed change rate is not less than the second set threshold, the drive wheel is determined to be in the air and an air-free flag is output; if the drive wheel is determined to be in the air, the air-free flag is output to facilitate the calculation of motor torque.

[0106] For example, the change in driving tire pressure p' and the rate of change in engine speed w' are obtained in real time through filtering and signal change rate calculation. When both exceed the threshold, i.e., p' ≥ p' max And w'≥w' max When the time is right, determine that the drive wheel is in the air and output the air-free flag.

[0107] 300. Based on the take-off marker and the first calculation rule, the desired motor torque of the vehicle and the motor torque at the moment the drive wheels are airborne are calculated.

[0108] In some embodiments, the step of calculating the desired motor torque of the vehicle and the motor torque at the moment the drive wheels are airborne, based on the airborne flag and a first calculation rule, includes:

[0109] After identifying the airborne marker, calculate the impact intensity of each shaft system:

[0110] Calculate the drive wheel clearance:

[0111]

[0112] Where g is the acceleration due to gravity, v is the speed of the driving wheel at the moment of takeoff, and θ is the angle between the vehicle and the ground at the moment of takeoff;

[0113] Calculate the time the drive wheels are off the ground:

[0114]

[0115] Where h is the height of the drive wheel off the ground;

[0116] Calculate the speed of the drive wheels at the moment of landing:

[0117]

[0118] Where I is the moment of inertia of the entire electric drive system, M0 is the motor torque at the moment the drive wheel is airborne, and i 1n is the transmission ratio from shaft 1 to shaft n, v is the speed of the driving wheel at the moment of takeoff, and T is the time the driving wheel is in the air.

[0119] Calculate the ground support force on the drive wheels at the moment of landing:

[0120]

[0121] Where m is the mass of the car;

[0122] Calculate the ground friction force at the moment the drive wheels touch down:

[0123] f = μF;

[0124] Where μ is the ground friction coefficient;

[0125] Calculate the impact torque on the output shaft system n:

[0126] M n =fr;

[0127] Where r is the radius of the drive wheel;

[0128] Calculate the impact torque on shaft system (n-1):

[0129] M n-1 =M n i (n-1)n ;

[0130] Among them, i (n-1)n The transmission ratio between shaft system (n-1) and shaft system n;

[0131] Calculate the impact torque on shaft 2:

[0132] M2 = M n i 2n ;

[0133] Among them, i 2n This refers to the transmission ratio between shaft system 2 and shaft system n.

[0134] Calculate the impact torque on shaft 1:

[0135] M1 = M n i 1n ;

[0136] Among them, i 1n This is the transmission ratio between shaft system 1 and shaft system n;

[0137] Calculate the impact force of shaft system 1:

[0138]

[0139] Among them, I w1 Let be the moment of inertia of shaft system 1;

[0140] Calculate the impact intensity of shaft system 2:

[0141]

[0142] Among them, I w2 Let be the moment of inertia of shaft system 2;

[0143] Calculate the impact intensity of shaft system (n-1):

[0144]

[0145] Among them, I wn-1 Let be the moment of inertia of the (n-1) axis system;

[0146] Calculate the impact intensity of shaft system n:

[0147]

[0148] Among them, I wn Let n be the moment of inertia of the axis system n;

[0149] Setting the impact intensity of each axle system equal to the critical safety threshold, multiple v' values ​​are calculated. The smallest v' value is taken as the desired drive wheel speed value of the vehicle.

[0150]

[0151] Where, a'1 is the impact threshold of shaft system 1, I w1 Let M1 be the moment of inertia of shaft system 1, and M1 be the impact torque acting on shaft system 1. 1n This is the transmission ratio between shaft system 1 and shaft system n;

[0152]

[0153] Where a'2 is the impact threshold of shaft system 2, I w2 Let M2 be the moment of inertia of shaft system 2, and M2 be the impact torque acting on shaft system 2. 2n This refers to the transmission ratio between shaft system 2 and shaft system n.

[0154]

[0155] Among them, a' n-1 I is the impact threshold of the shaft system (n-1). w(n-1)is the moment of inertia of the shafting (n - 1), M n-1 is the impact torque on the shafting (n - 1);

[0156]

[0157] where, a' n is the impact degree threshold of the shafting n, I wn is the moment of inertia of the shafting n, M n is the impact torque on the shafting n;

[0158] Calculate the expected driving wheel speed of the vehicle:

[0159] v' = min(v'1, v'2…v' n-1 , v' n );

[0160] Based on the expected driving wheel speed of the vehicle, obtain the expected motor torque when the vehicle falls:

[0161]

[0162] where, v' is the expected driving wheel speed, v is the driving wheel speed at the moment of takeoff, T is the driving wheel takeoff time, I is the moment of inertia of the entire electric drive system, i 1n is the transmission ratio between the shafting 1 and the shafting n;

[0163] According to the obtained expected motor torque M of the vehicle, compare it with the motor torque M0 at the moment of driving wheel takeoff. When M < M0, the output torque is the calculated value M; when M ≥ M0, the output torque is equal to the calculated value M0.

[0164] In the above implementation process, calculate the expected motor torque of the vehicle and the motor torque at the moment of driving wheel takeoff, so as to output the expected torque following curve, thereby performing feedback adjustment on the motor torque. At the same time, during the process of obtaining the motor torque, consider the impact performance of each shafting, effectively avoiding the overload problem of the electric drive system.

[0165] 400. Generate an expected torque following curve and adjust the output torque of the motor according to the expected torque following curve.

[0166] In some embodiments, the generating the expected torque following curve includes:

[0167] To improve the smoothness of the torque adjustment process and ensure that the adjustment time is controllable, design a cubic torque following curve as follows, convert the torque adjustment problem into an expected torque curve following problem, and the curve schematic diagram is as Figure 2 shown.

[0168] Design a cubic torque following curve, and the obtained curve of the expected torque changing with time is:

[0169]

[0170] Where M0 is the motor torque at the moment the drive wheels are airborne; M is the desired motor torque for the vehicle; t1 is the start control time; t f To control the end time; (t) f -t1) is the set torque adjustment time, which must be less than the time the drive wheels are off the ground.

[0171] In the above implementation process, a desired torque following curve is generated to enable feedback adjustment of the motor torque, transforming the torque adjustment problem into a desired torque curve following problem. This allows for adjustment of the torque adjustment time and ensures smooth torque adjustment.

[0172] In some embodiments, adjusting the motor output torque according to the desired torque following curve includes:

[0173] Using the three-dimensional torque following curve as the ideal tracking path for PID torque control, closed-loop feedback control is performed on the motor torque to adjust the output torque of the drive motor in real time, so that the motor torque when the drive wheel is in the air tracks the desired motor torque, thus protecting the electric drive system from shocks within a safe range.

[0174] For example, Figure 3 The diagram shows the real-time torque control block diagram. The ideal tracking path for PID torque control is a cubic torque following curve. The PID controller outputs control commands to the drive motor and control system. The drive motor and control system provide feedback on the motor torque, and closed-loop feedback control is performed on the motor torque to adjust the output torque of the drive motor in real time. This ensures that the motor torque when the drive wheels are off the ground tracks the desired motor torque, thus protecting the electric drive system from impacts within a safe range. A BP neural network is used to tune the three control parameters of the PID controller online to improve the adaptability of the PID controller.

[0175] In the above implementation process, the output torque of the motor is adjusted and optimized according to the desired torque following curve in order to avoid overload of the electric drive system caused by excessive speed change after the drive wheel is off the ground.

[0176] In the above implementation process, the operating parameters of the vehicle's drive wheels are obtained; if the operating parameters meet the first operating condition rule, it is determined that the drive wheels are airborne and an airborne flag is output; based on the airborne flag and the first calculation rule, the desired motor torque of the vehicle and the motor torque at the moment the drive wheels are airborne are calculated; a desired torque following curve is generated, and the output torque of the motor is adjusted according to the desired torque following curve; in order to optimize the motor torque output of the new energy vehicle under specific operating conditions, so as to avoid the problem of electric drive system overload caused by excessive speed change after the drive wheels are airborne.

[0177] The steps described above are not strictly performed in the order of their numbers; they should be understood as a whole.

[0178] Secondly, based on the above embodiments, Figure 4 This is a schematic diagram of the structure of an electric drive system torque control device provided in an embodiment of this application. (Reference) Figure 4 The electric drive system torque control device provided in this embodiment specifically includes: a parameter acquisition module 401, a lift-off determination module 402, a torque calculation module 403, and a torque adjustment module 404.

[0179] The parameter acquisition module 401 is used to acquire the operating parameters of the vehicle's drive wheels; the air-lift determination module 402 is used to determine that the drive wheels are air-lifted when the operating parameters meet the first operating condition rule, and output an air-lift flag; the torque calculation module 403 is used to calculate the vehicle's desired motor torque and the motor torque at the moment the drive wheels are air-lifted based on the air-lift flag and the first calculation rule; and the torque adjustment module 404 is used to generate a desired torque following curve and adjust the motor's output torque according to the desired torque following curve.

[0180] As described above, the embodiments of this application obtain the operating parameters of the vehicle's drive wheels; when the operating parameters meet the first operating condition rule, it is determined that the drive wheels are off the ground and an off-ground flag is output; based on the off-ground flag and the first calculation rule, the desired motor torque and the motor torque at the moment the drive wheels are off the ground are calculated; a desired torque following curve is generated, and the output torque of the motor is adjusted according to the desired torque following curve; in order to optimize the motor torque output of the new energy vehicle under specific operating conditions, so as to avoid the problem of electric drive system overload caused by excessive speed change after the drive wheels are off the ground.

[0181] The electric drive system torque control device provided in this application embodiment can be used to execute the electric drive system torque control method provided in the above embodiment, and has corresponding functions and beneficial effects.

[0182] Thirdly, embodiments of this application also provide an electronic device that can integrate the electric drive system torque control device provided in embodiments of this application. Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. (Reference) Figure 5 The electronic device includes an input device 73, an output device 74, a memory 72, and one or more processors 71. The memory 72 stores one or more programs. When the one or more programs are executed by the one or more processors 71, the one or more processors 71 implement the electric drive system torque control method provided in the above embodiments. The input device 73, output device 74, memory 72, and processors 71 can be connected via a bus or other means. Figure 5Taking the example of a connection between China and Israel via a bus.

[0183] The processor 71 executes various functional applications and data processing of the device by running software programs, instructions and modules stored in the memory 72, thereby realizing the above-mentioned electric drive system torque control method.

[0184] The electronic device provided above can be used to execute the electric drive system torque control method provided in the above embodiments, and has corresponding functions and beneficial effects.

[0185] Fourthly, embodiments of this application also provide a computer-readable storage medium, which includes a stored computer program; wherein, when the computer program is running, it controls the device where the computer-readable storage medium is located to execute the electric drive system torque control method as described above, and can achieve the same beneficial effects.

[0186] Of course, the computer-executable instructions provided in the embodiments of this application are not limited to the electric drive system torque control method described above, but can also execute related operations in the electric drive system torque control method provided in any embodiment of this application.

[0187] Fifthly, embodiments of this application also provide a computer program product. The methods described in the various embodiments of this application can be implemented entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the various embodiments of this application are executed entirely or partially. The computer can be a general-purpose computer, a special-purpose computer, a computer network, network equipment, user equipment, core network equipment, OAM (Open Application Model), or other programmable devices.

[0188] The computer program or instructions may be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions may be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium may be any available medium that a computer can access, or a data storage device such as a server or data center that integrates one or more available media. The available medium may be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; or an optical medium, such as a digital video optical disc; or a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or non-volatile storage medium, or may include both volatile and non-volatile types of storage media.

[0189] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0190] In addition, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0191] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause an electronic device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0192] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0193] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0194] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. An electric drive system torque control method, characterized by, The method comprises the following steps: acquiring a working condition parameter of a driving wheel of a vehicle; determining that the driving wheel is in flight and outputting a flight flag bit when the working condition parameter meets a first working condition rule; calculating a vehicle expected motor torque and a motor torque at a driving wheel flight moment based on the flight flag bit and a first calculation rule; generating an expected torque following curve and adjusting an output torque of the motor according to the expected torque following curve; the calculation of the vehicle expected motor torque and the motor torque at the driving wheel flight moment based on the flight flag bit and the first calculation rule comprises the following steps: calculating a driving wheel ground clearance: ； where g is the acceleration of gravity, v is the speed of the drive wheels at the moment of take-off, is the angle between the vehicle and the ground at the moment of take-off. calculating a driving wheel flight time: ； wherein h is the driving wheel ground clearance; calculating a driving wheel speed at a landing moment: ； Wherein, I is the whole electric drive system of inertia, The motor torque of the driving wheel at the moment of take-off, The transmission ratio of shaft system 1 to shaft system n, v is the speed of the driving wheel at the moment of take-off, T is the take-off time of the driving wheel; calculating a ground support force received by the driving wheel at the landing moment: ； wherein m is the mass of the vehicle; calculating a ground friction force at the landing moment of the driving wheel: ； wherein is the coefficient of ground friction; calculating an impact torque received by an output shaft system n: ； wherein r is the radius of the driving wheel; calculating an impact torque received by a shaft system (n-1): ； wherein, is the transmission ratio between the shaft train (n-1) and the shaft train n; calculating an impact torque received by a shaft system 2: ； wherein, is the transmission ratio between the shafting 2 and the shafting n; calculating an impact torque received by a shaft system 1: ； wherein, is the transmission ratio between the shafting 1 and the shafting n; calculating an impact degree of the shaft system 1: ； wherein, J is the moment of inertia of the shafting 1; calculating an impact degree of the shaft system 2: ； wherein, J is the moment of inertia of the shafting 2; calculating an impact degree of the shaft system (n-1): ； wherein is the moment of inertia of the shafting (n-1); calculating an impact degree of the shaft system n: ； wherein, is the moment of inertia of the shafting n; Let each shaft system impact degree equal to the safety threshold critical value, calculate a plurality of values, take the minimum value as the vehicle expected drive wheel speed value: ； wherein, is a threshold of the impact degree of the shafting 1, is a moment of inertia of the shafting 1, is an impact torque received by the shafting 1, is a transmission ratio between the shafting 1 and the shafting n; ； wherein, is a threshold of impact degree of the shafting 2, is a moment of inertia of the shafting 2, is an impact torque received by the shafting 2, is a transmission ratio between the shafting 2 and the shafting n; ； wherein, is the threshold value of the impact degree of the shaft system (n-1), is the moment of inertia of the shaft system (n-1), is the impact torque received by the shaft system (n-1); ； wherein, is a threshold value of the impact degree of the shaft system n, is the moment of inertia of the shaft system n, is the impact torque received by the shaft system n; calculating a vehicle expected driving wheel speed: ； obtaining a vehicle expected motor torque when the vehicle is falling based on the vehicle expected driving wheel speed: ； wherein, is the desired drive wheel speed, is the drive wheel speed at the moment of lift-off, T is the drive wheel lift-off time, I is the moment of inertia of the entire electric drive system, is the transmission ratio between the shaft system 1 and the shaft system n; According to the obtained vehicle desired motor torque M, the motor torque at the moment of takeoff of the drive wheel is compared , the output torque is the calculated value M; when , the output torque is equal to the calculated value , the output torque is equal to the calculated value .

2. The electric drive system torque control method according to claim 1, characterized by, the acquisition of the working condition parameter of the driving wheel of the vehicle comprises the following steps: real-time acquisition of a tire pressure change amount and a rotational speed change rate of the driving wheel of the vehicle.

3. The electric drive system torque control method of claim 1, wherein, the determination that the driving wheel is in flight and the output of the flight flag bit when the working condition parameter meets the first working condition rule comprise the following steps: when the tire pressure change amount is not less than a first set threshold value and the rotational speed change rate is not less than a second set threshold value, it is determined that the driving wheel is in flight, and the flight flag bit is output.

4. The electric drive system torque control method of claim 1, wherein, the generation of the expected torque following curve comprises the following steps: designing a cubic torque following curve, so that the expected torque following curve changing with time is: ； wherein, M is the motor torque at the moment of the drive wheel leaving the ground; M is the desired motor torque of the vehicle; T is the start control time; T is the end control time; T is the set torque adjustment time, which must be less than the drive wheel leaving the ground time.

5. The electric drive system torque control method according to claim 4, characterized by, the adjustment of the output torque of the motor according to the expected torque following curve comprises the following steps: the cubic torque following curve is used as a PID torque control ideal tracking path to perform closed-loop feedback control on the motor torque, so as to real-time adjust the output torque of the driving motor, so that the motor torque when the driving wheel is in flight tracks the expected motor torque, and the impact received by the electric drive system is within a safe range.

6. An electric drive system torque control device characterized by comprising: the method implementation based on claim 1 comprises: a parameter acquisition module, configured to acquire a working condition parameter of a driving wheel of a vehicle; a flight determination module, configured to determine that the driving wheel is in flight and output a flight flag bit when the working condition parameter meets a first working condition rule; a torque calculation module, configured to calculate a vehicle expected motor torque and a motor torque at a driving wheel flight moment based on the flight flag bit and a first calculation rule; a torque adjustment module, configured to generate an expected torque following curve and adjust an output torque of the motor according to the expected torque following curve.

7. An electronic device, comprising: The method comprises the following steps: a processor, a memory and a bus, the processor being connected with the memory through the bus, the memory storing computer readable instructions, when the computer readable instructions are executed by the processor, the computer readable instructions are used to implement the torque control method of the electric drive system as claimed in any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, The computer readable storage medium stores a computer program, and the computer program is executed by the server to implement the electric drive system torque control method according to any one of claims 1-5.

9. A computer program product, characterised in that, The computer program product comprises instructions which, when executed by a computer, cause the computer to implement the electric drive system torque control method according to any one of claims 1-5.

Images