Control methods for vehicle drivetrains, vehicle drivetrains and construction machinery

Abstract

This invention relates to the field of vehicle technology, providing a control method for a vehicle drive assembly, a vehicle drive assembly, and engineering machinery. When the assembly is powered on, the two controllers within the assembly first perform a pre-charge circuit fault self-check. After passing the fault self-check, the two controllers communicate and negotiate, electing one as the master controller and the other as the slave controller, rather than having the master and slave designated by an external unit, thus achieving distributed decision-making. After the pre-charge handshake within the assembly, synchronous pre-charge occurs. During pre-charge, the master and slave controllers monitor the assembly bus voltage in real time and provide feedback confirmation signals. The master controller executes the main contactor engagement action based on the confirmation signal. Therefore, through voltage feedback synchronous pre-charge, the final pre-charge execution actions of the two controllers can maintain strict synchronization, fundamentally solving the problems of "dynamic current competition" and "system decision paralysis" caused by a lack of coordination between controllers.

Description

Technical Field

[0001] This invention relates to the field of vehicle technology, specifically to a control method for a vehicle drive assembly, a vehicle drive assembly, and engineering machinery. Background Technology

[0002] In construction machinery, engineering vehicles (such as boom trucks and mining trucks) often adopt a multi-disc drive architecture, for example, the front and rear axles are each controlled by an independent electric drive disc. Each disc contains two controllers (master and slave controllers, sharing a master contactor), and their DC bus is connected through copper busbars inside the disc, but the busbars between different discs are physically and electrically isolated.

[0003] Currently, the internal pre-charging during the power-on initialization phase of the aforementioned disk assembly typically employs the following method: 1. Only the main controller pre-charges within the panel: The pre-charging circuit of a single controller needs to charge the bus capacitors of the entire panel, which significantly slows down the pre-charging process and affects the user experience. The pre-charging circuit of the main controller is under overload stress for a long time, which makes it prone to aging. Once it fails, the entire panel will not work, which can easily lead to a single point of failure. 2. Independent pre-charging of two controllers inside the panel: Since the controller initialization power-on sequence may be sequential during the power-on process, independent pre-charging will lead to dynamic current competition and asynchronous control sequence, which may cause unpredictable and repeated electrical and thermal stress shocks to the components, accelerate the aging of the pre-charging circuit, and may cause the entire system to fail to operate due to a single control pre-charging circuit failure. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the first objective of this invention is to provide a control method for a vehicle drive system.

[0005] The second objective of this invention is to provide a vehicle drive assembly.

[0006] The third objective of this invention is to provide an engineering machine.

[0007] The technical solution adopted in this invention is as follows: An embodiment of the first aspect of the present invention provides a control method for a vehicle drive unit, the vehicle drive unit including a front axle drive unit and a rear axle drive unit, each of the front axle drive unit and the rear axle drive unit including two controllers, one of which is connected to a power battery via a main contactor. The method includes the following steps: upon receiving a power-on command for the drive unit, each of the two controllers within the front axle drive unit and the rear axle drive unit performs a pre-charge circuit fault self-check; if neither of the two controllers within the front axle drive unit or the rear axle drive unit has a fault in its pre-charge circuit, then the controller connected to the main contactor is selected as the master controller within the unit. One controller acts as a master controller, and the other acts as a slave controller within the group. The master controller and slave controller within the group perform a pre-charge handshake. The master controller and slave controller within the group perform synchronous pre-charge. The master controller within the group continuously monitors the bus voltage of the group panel in real time. When the detected bus voltage of the group panel is greater than or equal to a set voltage threshold, it sends a master contactor activation command for the group panel to the corresponding slave controller. After receiving the master contactor activation command, the slave controller within the group acquires the bus voltage and pre-charge time of the group panel in real time, and sends a confirmation signal back to the corresponding master controller based on the bus voltage and pre-charge time. The master controller within the group executes the master contactor activation action based on the confirmation signal.

[0008] The vehicle drivetrain control method proposed above in this invention may also have the following additional technical features: According to an embodiment of the present invention, the above-described control method for a vehicle drive group further includes: if a fault exists in the pre-charge circuit of one of the controllers, the fault-free controller is nominated as the master controller in the group, and the other is designated as a slave controller; the master controller performs pre-charge and monitors the group bus voltage in real time; when the detected group bus voltage is greater than or equal to a set voltage threshold, the master controller sends a main contactor engagement command for the group to the corresponding slave controller; the slave controller receives the main contactor engagement command; the controller actually connected to the main contactor performs the main contactor engagement action; if both controller pre-charge circuits are faulty, both controllers report the fault.

[0009] According to one embodiment of the present invention, the master controller and slave controller within the group perform a precharge handshake, specifically including: the master controller sending a precharge preparation instruction to the slave controller; the slave controller performing a self-check of its own initialization program status; if a fault is detected in its own initialization program, the slave controller reports the fault; if no fault is detected in its own initialization program, the slave controller replies with a ready signal to the master controller.

[0010] According to one embodiment of the present invention, the slave controller feeds back an acknowledgment signal to the corresponding master controller based on the bus voltage of the circuit board and the pre-charge time. Specifically, the slave controller determines the total pre-charge time when the bus voltage of the circuit board reaches a set voltage threshold; if the total pre-charge time is less than the set time, the slave controller feeds back an acknowledgment signal to the corresponding master controller; if the total pre-charge time is greater than or equal to the set time, the slave controller records a secondary fault flag bit and then feeds back an acknowledgment signal to the corresponding master controller.

[0011] According to one embodiment of the present invention, after the master controller and slave controller in the group perform a pre-charge handshake, the method further includes: the master controller and the slave controller synchronously detecting whether a secondary positioning fault flag is recorded; if neither records a secondary positioning fault flag, then the step of synchronous pre-charging of the master controller and slave controller in the group is executed.

[0012] According to an embodiment of the present invention, the above-described control method for a vehicle drive group further includes: if any controller records the secondary positioning fault flag, then only the main controller performs pre-charging; the main controller detects the group bus voltage; if the main controller detects that the group bus voltage is greater than or equal to a set voltage threshold, then the main controller actively discharges; the main controller sends a pre-charging command to the slave controllers in the group, so that the slave controllers pre-charge independently; the slave controller detects the group bus voltage; if the slave controller detects that the group bus voltage is greater than or equal to a set voltage threshold, then after the slave controller actively discharges, the step of synchronous pre-charging by the main controller and the slave controllers in the group is executed.

[0013] According to an embodiment of the present invention, the above-described vehicle drive assembly control method further includes: if the main controller detects that the assembly bus voltage is less than the set voltage threshold, the main controller records and increases the number of pre-charge faults; the main controller determines whether the recorded number of pre-charge faults has reached the set number; if the number of pre-charge faults recorded by the main controller has not reached the set number, the process returns to the pre-charge step performed only by the main controller; if the number of pre-charge faults recorded by the main controller has reached the set number, the process of the main controller actively discharging is executed.

[0014] According to an embodiment of the present invention, the above-described control method for the vehicle drive assembly further includes: if the slave controller detects that the assembly bus voltage is less than the set voltage threshold, the slave controller records and increases the number of pre-charge faults; the slave controller determines whether the recorded number of pre-charge faults has reached the set number; if the number of pre-charge faults recorded by the slave controller has not reached the set number, the process returns to the pre-charge step performed only by the main controller; if the number of pre-charge faults recorded by the slave controller has reached the set number, the process of the slave controller actively discharging is executed.

[0015] A second aspect of the present invention provides a vehicle drive assembly, the vehicle drive assembly including a front axle drive assembly and a rear axle drive assembly, both the front axle drive assembly and the rear axle drive assembly including two controllers, one of which is connected to a power battery via a main contactor, the front axle drive assembly and the rear axle drive assembly being configured to execute the control method of the vehicle drive assembly described in the first aspect of the present invention.

[0016] A third aspect of the present invention provides an engineering machine including the vehicle drive assembly described in the second aspect of the present invention.

[0017] The beneficial effects of this invention are: The components of this invention do not require communication and do not interfere with each other, which greatly simplifies the design of the whole vehicle system and improves the reusability and maintainability of the modules.

[0018] When the disk assembly is powered on, the present invention perfectly solves the problems of pre-charge competition and asynchrony within the disk assembly through dynamic election, status handshake and voltage synchronization within the disk assembly.

[0019] This invention achieves fault tolerance at the assembly level. The failure of a single controller precharger does not affect the basic functions of the assembly, and the whole vehicle indirectly achieves a higher level of redundancy. When the main controller precharger of the current assembly fails, it degrades internally, and the subsequent assemblies also operate independently. The whole vehicle will not cause a drive axle to fail completely due to a partial failure of a single controller, and the system is extremely robust.

[0020] This invention introduces "grouped step-by-step fault location", which enables accurate identification of fault controllers and fundamentally solves the problem of "system-level decision paralysis" in the prior art, elevating fault diagnosis from "reporting anomalies" to "locating the source of the fault". Attached Figure Description

[0021] Figure 1 This is a flowchart of a vehicle drive assembly control method according to the first embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a front axle drive assembly or a rear axle drive assembly according to an embodiment of the present invention. Figure 3 This is a flowchart of a vehicle drive assembly control method according to a second embodiment of the present invention; Figure 4 This is a flowchart of a vehicle drive assembly control method according to a third embodiment of the present invention; Figure 5 This is a flowchart of a vehicle drive assembly control method according to a fourth embodiment of the present invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Figure 1 This is a flowchart of a vehicle drivetrain control method according to a first embodiment of the present invention. Figure 2 This is a schematic diagram of the structure of a front axle drive assembly or a rear axle drive assembly according to an embodiment of the present invention.

[0024] The vehicle drivetrain includes a front axle drivetrain and a rear axle drivetrain. The front and rear axle drivetrains have identical structures, driving the front and rear axle motors respectively. Both drivetrains include two controllers, one of which is connected to the power battery via a main contactor K. Taking the front axle drivetrain as an example... Figure 2 As shown, the front axle drive assembly may include a first controller and a second controller, with one controller (the first controller) connected to the main contactor K. The positive and negative terminals of the two controllers' busbars are connected via copper busbars. The two output pins of the first controller are connected to the main contactor K, controlling its engagement and disengagement. The positive terminal (+) of the power battery is connected to the positive copper busbars of the first and second controllers after passing through the main contactor K. The negative terminal (−) of the battery is directly connected to the negative copper busbars of the first and second controllers. The first and second controllers are connected via CAN (Controller Area Network). The Area Network (Controller Area Network) bus (CAN_H and CAN_L) is connected at a baud rate of 250Kbps. The first controller of the front axle drive unit controls the front left motor, and the second controller controls the front right motor. The pre-charge resistance of both controllers is 17.5 ohms. The total capacitance of the controller capacitor board is 9900 microfarads. In actual testing, if a single controller pre-charges the drive unit to 95% of the battery voltage, the pre-charge time is about 1.5 seconds. If both controllers pre-charge the drive unit simultaneously, the pre-charge time is about 0.75 seconds. The controller chip has built-in internal storage EEPROM (Electrically Erasable Programmable Read Only Memory). The EEPROM is used to store fault records for a long time and will not be lost when power is off. All storage-related information below is stored in the EEPROM of the controller chip.

[0025] The vehicle drive assembly is the vehicle drive axle; the front axle drive assembly is the front drive axle, and the rear axle drive assembly is the rear drive axle.

[0026] like Figure 1 As shown, the vehicle drive assembly control method of the present invention includes the following steps: S1, when the power-on command of the drive assembly is received, the two controllers in the front axle drive assembly and the rear axle drive assembly perform pre-charge circuit fault self-checks respectively.

[0027] S2, if there is no fault in the precharge circuit of either of the two controllers in the front axle drive group or the rear axle drive group, the controller connected to the main contactor is elected as the master controller in the group, and the other is elected as the slave controller in the group.

[0028] Specifically, after the drive group is powered on, the two controllers in the front axle drive group and the rear axle drive group each perform a pre-charge circuit fault self-check to determine whether there is a fault in the pre-charge function. If there is no fault in either controller in the group, it means that the pre-charge function of the drive group is normal, and a normal dynamic role election is carried out within the group. The controller actually connected to the main contactor is elected as the master controller in the group, and the other becomes the slave controller in the group. Thus, the controllers negotiate equally through internal communication, rather than being designated as master and slave by external units, thereby realizing distributed decision-making.

[0029] It is understood that the master controller and slave controller in this invention refer to the group, which refers to the drive group disk in which it is located.

[0030] S3, the master controller and slave controller in the group perform a pre-charge handshake.

[0031] S4, the main controller and slave controller in the group perform synchronous pre-charging.

[0032] S5, the main controller in the group continuously monitors the bus voltage of the group panel in real time. When the detected bus voltage of the group panel is greater than or equal to the set voltage threshold, it sends a command to the corresponding slave controller to engage the main contactor of the group panel.

[0033] Specifically, the voltage threshold is typically set at 95% of the power battery voltage.

[0034] S6: After receiving the main contactor's engagement command, the slave controller in the group acquires the group bus voltage and pre-charge time in real time, and sends a confirmation signal to the corresponding main controller based on the group bus voltage and pre-charge time.

[0035] S7, the main controller in the group executes the main contactor engaging action based on the confirmation signal.

[0036] Specifically, after the master controller and slave controller within the group perform a pre-charge handshake, they synchronously pre-charge. During the pre-charge process, the master controller monitors the group bus voltage in real time. When it detects that the voltage is greater than or equal to 95% of the battery voltage, it sends a main contactor activation command to the slave controller. Upon receiving the activation command, the slave controller determines whether its monitored group bus voltage and pre-charge time meet the requirements. If so, the slave controller sends a confirmation signal to the master controller, which then executes the main contactor activation action based on the confirmation signal. Thus, through voltage feedback synchronous pre-charge, the final pre-charge execution actions of the two controllers can remain strictly synchronized, fundamentally solving the problems of "dynamic current competition" and "system decision paralysis" caused by a lack of coordination between controllers.

[0037] As described above, the modules of this invention do not require communication and do not interfere with each other, greatly simplifying the overall vehicle system design and improving the reusability and maintainability of the modules. When the modules are powered on, the pre-charge competition and asynchrony problems within the modules are perfectly solved through dynamic election, status handshake and voltage synchronization within the modules.

[0038] According to one embodiment of the present invention, such as Figure 3 As shown, the control method for the vehicle drivetrain also includes: S8, if one of the controllers' precharge circuits is faulty, the fault-free controller is elected as the master controller in the group, and the other becomes the slave controller.

[0039] S9, the main controller performs pre-charging and monitors the bus voltage of the panel in real time.

[0040] S10, when the bus voltage of the panel is detected to be greater than or equal to the set voltage threshold, the main controller sends a main contactor activation command for the panel to the corresponding slave controller.

[0041] S11, Receive the main contactor engaging command from the controller.

[0042] S12, the controller actually connected to the main contactor executes the main contactor's engaging action.

[0043] S13, if both controller precharge circuits are faulty, both controllers will report the fault.

[0044] Specifically, upon receiving the power-on command for the drive unit, the controller within the unit first performs a pre-charge circuit fault self-check. If both controllers are faulty, they report the fault. After reporting the fault, the controller will no longer respond to vehicle commands and will wait for maintenance personnel to inspect and replace the controller. If one controller's pre-charge circuit is faulty, the fault-free controller is elected as the master controller within the unit, and the other becomes the slave controller. The master controller begins pre-charging and, after pre-charging, continuously monitors whether the bus voltage is greater than 95% of the power battery voltage. If the drive unit bus voltage reaches 95% of the power battery voltage within 2 seconds, the master controller sends a main contactor engagement command for the drive unit to the corresponding slave controller. The slave controller receives the main contactor engagement command, and finally, the controller actually connected to the main contactor executes the engagement action. If the drive unit bus voltage does not reach 95% of the battery voltage within 2 seconds, the controller reports a pre-charge fault and shuts down. Therefore, the above-mentioned "intelligent degradation" strategy enables the drive axle to automatically reconstruct and maintain its function without external intervention after a single point of failure. This achieves a leap from "hardware backup" to "functional redundancy". The entire vehicle will not cause a drive axle to completely fail due to a partial failure of a single controller. When the main control precharge of the front axle drive axle is damaged, it will degrade internally, while the rear axle drive axle will operate independently. The system is extremely robust and indirectly achieves a higher level of redundancy in the entire vehicle.

[0045] In one embodiment of the present invention, such as Figure 4 As shown, the master controller and slave controller within the system perform a pre-charge handshake, specifically including: S31, the main controller sends a pre-charge preparation command to the slave controller.

[0046] S32 performs a self-check of its own initialization program status from the controller.

[0047] S33, if a fault is detected in its own initialization program, the fault is reported from the controller.

[0048] S34, if it detects that there is no fault in its own initialization program, it replies a ready signal to the main controller.

[0049] Specifically, if there are no faults in the precharge circuits of the two controllers in the group, the master controller sends a precharge preparation command to the slave controller; after the slave controller completes its own status check, it replies with a ready signal to the master controller. After receiving the ready signal, the master controller starts precharging. The slave controller starts precharging after a delay of one communication cycle after replying with the ready signal, thereby realizing synchronous precharging of the master controller and slave controller in the group.

[0050] In one embodiment of the present invention, such as Figure 5 As shown, the controller sends a confirmation signal to the corresponding main controller based on the bus voltage and pre-charge time of the control panel. Specifically, this includes: S61, the controller determines whether the total pre-charge time when the bus voltage of the panel reaches the set voltage threshold is less than the set time.

[0051] S62, if the total precharge time is less than the set time, the controller sends a confirmation signal to the corresponding main controller.

[0052] The time setting can be 1 second.

[0053] S63, if the total precharge time is greater than or equal to the set time, after recording the secondary fault flag bit from the controller, a confirmation signal is sent back to the corresponding main controller.

[0054] Specifically, after receiving the main contactor's engagement command, the controller acquires the panel bus voltage and pre-charge time in real time. It determines the total pre-charge time required for the panel bus voltage to reach the set voltage threshold. If the total pre-charge time is less than 1 second, the slave controller sends a confirmation signal to the corresponding master controller. If the total pre-charge time is greater than or equal to 1 second, it indicates a potential pre-charge fault in the slave controller. The slave controller records the secondary fault flag and sends a confirmation signal to the corresponding master controller. Then, the controller actually connected to the main contactor executes the engagement action. This not only allows for secondary fault detection but also ensures strict synchronization of the pre-charge actions of the two controllers within the panel.

[0055] According to one embodiment of the present invention, such as Figure 5 As shown, after the master controller and slave controller in the above group perform a pre-charge handshake, it also includes: S14, both the master controller and slave controller synchronously detect whether a secondary positioning fault flag has been recorded.

[0056] If no secondary location fault flag is recorded, then the main controller and slave controller in the group shall perform synchronous pre-charging.

[0057] S15, if any controller records a secondary positioning fault flag, then only the main controller will perform pre-charging.

[0058] S16, the main controller detects whether the voltage of the busbar of the control panel is greater than or equal to the set voltage threshold.

[0059] S17. If the main controller detects that the voltage of the busbar of the control panel is greater than or equal to the set voltage threshold, the main controller will actively discharge.

[0060] S18, the main controller sends a precharge command to the slave controllers in the group so that the slave controllers can precharge individually.

[0061] S19, detect from the controller whether the bus voltage of the control panel is greater than or equal to the set voltage threshold.

[0062] S110, if the voltage of the busbar detected by the controller is greater than or equal to the set voltage threshold, then after the controller actively discharges, the main controller and the slave controller in the group shall perform synchronous pre-charging.

[0063] S111 If the main controller detects that the bus voltage of the control panel is less than the set voltage threshold, the main controller records and increases the number of pre-charge faults.

[0064] S112, the main controller determines whether the number of recorded precharge failures has reached the set number.

[0065] If the number of pre-charge failures recorded by the main controller does not reach the set number, the process returns to the pre-charge step performed only by the main controller; if the number of pre-charge failures recorded by the main controller reaches the set number, the process executes the active discharge step performed by the main controller.

[0066] S113 If the voltage of the busbar detected by the controller is less than the set voltage threshold, the controller will record and increase the number of pre-charge faults.

[0067] S114, the controller determines whether the number of precharge failures recorded has reached the set number.

[0068] If the number of pre-charge failures recorded from the controller does not reach the set number, the process returns to the step of pre-charging only from the main controller; if the number of pre-charge failures recorded from the controller reaches the set number, the process of actively discharging from the controller is executed.

[0069] Specifically, if the controller detects an anomaly during synchronous pre-charging (such as pre-charging time exceeding 1 second), it records a "secondary location fault flag." Upon the next power-on, after the main controller and slave controller perform a pre-charging handshake, a grouped step-by-step fault location process is initiated: first, only the main controller performs a pre-charging test, and then actively discharges after completion; subsequently, the slave controller is instructed to perform a pre-charging test independently. Through this step-by-step test, it is possible to accurately determine which controller's pre-charging circuit has failed, achieving precise identification of the faulty controller. This fundamentally solves the problem of "system-level decision paralysis" in existing technologies, elevating fault diagnosis from "reporting anomalies" to "locating the fault source."

[0070] If any controller reports a pre-charge fault three times consecutively, the panel internally determines that the pre-charge circuit of that controller is damaged. In the subsequent internal role election, the faulty controller will lose its right to be elected, and the only healthy controller in the panel will assume all pre-charge responsibilities. After pre-charge is completed, a command is sent to the controller connected to the main contactor to execute the main contactor's engaging action, ensuring that the panel can still work after degradation. The above-mentioned "intelligent degradation" strategy enables the panel to automatically reconstruct and maintain its functionality without external intervention after a single point of failure, achieving a leap from "hardware backup" to "functional redundancy".

[0071] In embodiments of the present invention, the front axle drive assembly and the rear axle drive assembly independently perform the steps of the above method.

[0072] In summary, the vehicle drive cluster control method according to embodiments of the present invention, when the cluster is powered on, the two controllers within the cluster first perform a pre-charge circuit fault self-check. After the fault self-check passes, the two controllers within the cluster communicate and negotiate to elect one as the master controller of the cluster and the other as the slave controller, rather than having the master and slave designated by an external unit, thus realizing distributed decision-making. After the cluster's internal pre-charge handshake, synchronous pre-charge is performed. During pre-charge, the master controller and the slave controller monitor the cluster bus voltage in real time and provide feedback confirmation signals. The master controller executes the main contactor energizing action based on the confirmation signal. Thus, through voltage feedback synchronous pre-charge, the final pre-charge execution actions of the two controllers can maintain strict synchronization, fundamentally solving the problems of "dynamic current competition" and "system decision paralysis" caused by the lack of coordination between controllers. Fault tolerance at the cluster level is achieved; damage to the pre-charge of a single controller does not affect the basic function of the cluster. The entire vehicle indirectly achieves a higher level of redundancy. When the master controller pre-charge of the current cluster fails, its internal operation is degraded, and subsequent clusters also operate independently. The entire vehicle will not cause the complete failure of a drive axle due to a partial failure of a single controller, resulting in extremely strong system robustness. The introduction of "grouped step-by-step fault location" enables accurate identification of fault controllers, fundamentally solving the problem of "system-level decision paralysis" in existing technologies and elevating fault diagnosis from "reporting anomalies" to "locating the source of the fault".

[0073] Corresponding to the control method of the vehicle drive assembly described above, the present invention also proposes a vehicle drive assembly.

[0074] The vehicle drive assembly of this invention includes a front axle drive assembly and a rear axle drive assembly. The front axle drive assembly and the rear axle drive assembly each include two controllers, one of which is connected to the power battery via a main contactor. The front axle drive assembly and the rear axle drive assembly are configured to execute the control method of the vehicle drive assembly described above.

[0075] According to an embodiment of the present invention, when the vehicle drive assembly is powered on, the two controllers within the assembly first perform a pre-charge circuit fault self-check. After the fault self-check passes, the two controllers communicate and negotiate to elect one as the master controller of the assembly and the other as the slave controller, rather than having the master and slave designated by an external unit, thus realizing distributed decision-making. After the pre-charge handshake within the assembly, synchronous pre-charge is performed. During pre-charge, the master controller and the slave controller monitor the assembly bus voltage in real time and feed back a confirmation signal. The master controller executes the main contactor to engage based on the confirmation signal. Thus, through voltage feedback synchronous pre-charge, the final pre-charge execution actions of the two controllers can maintain strict synchronization, fundamentally solving the problems of "dynamic current competition" and "system decision paralysis" caused by the lack of coordination between controllers.

[0076] In addition, the present invention also proposes an engineering machine, including the vehicle drive assembly described above.

[0077] According to the engineering machinery of the present invention, when the vehicle drive assembly is powered on, the two controllers within the assembly first perform a pre-charge circuit fault self-check. After the fault self-check passes, the two controllers communicate and negotiate to elect one as the master controller of the assembly and the other as the slave controller, instead of having the master and slave designated by an external unit, thus realizing distributed decision-making. After the pre-charge handshake within the assembly, synchronous pre-charge is performed. During pre-charge, the master controller and the slave controller monitor the assembly bus voltage in real time and provide feedback confirmation signals. The master controller executes the main contactor energizing action based on the confirmation signal. Thus, through voltage feedback synchronous pre-charge, the final pre-charge execution actions of the two controllers can maintain strict synchronization, fundamentally solving the problems of "dynamic current competition" and "system decision paralysis" caused by the lack of coordination between controllers.

[0078] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0079] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0080] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of the invention pertain.

[0081] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0082] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any of the following techniques known in the art, or a combination thereof: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0083] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0084] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0085] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A control method for a vehicle drivetrain, characterized in that, The vehicle drive assembly includes a front axle drive assembly and a rear axle drive assembly. Both the front axle drive assembly and the rear axle drive assembly include two controllers, one of which is connected to the power battery via a main contactor. The method includes the following steps: When a power-on command is received for the drive assembly, the two controllers within the front axle drive assembly and the rear axle drive assembly each perform a pre-charge circuit fault self-check. If there is no fault in the precharge circuit of either the front axle drive group or the two controllers in the rear axle drive group, the controller connected to the main contactor is elected as the master controller in the group, and the other is the slave controller in the group. The master controller and slave controllers within the group perform a pre-charge handshake. The master controller and slave controller within the group perform synchronous pre-charging; The main controller within the group continuously monitors the bus voltage of the group panel in real time. When the detected bus voltage of the group panel is greater than or equal to a set voltage threshold, it sends a command to the corresponding slave controller to engage the main contactor of the group panel. After receiving the main contactor engagement command, the slave controller in the group acquires the group bus voltage and pre-charge time in real time, and sends a confirmation signal to the corresponding main controller based on the group bus voltage and pre-charge time. The main controller within the group executes the main contactor engaging action based on the confirmation signal.

2. The control method for the vehicle drive assembly according to claim 1, characterized in that, Also includes: If one of the controllers' precharge circuits fails, the controller that is not faulty is elected as the master controller in the group, and the other becomes the slave controller. The main controller performs pre-charging and monitors the bus voltage of the panel in real time; When the bus voltage of the panel is detected to be greater than or equal to a set voltage threshold, the main controller sends a main contactor activation command for the panel to the corresponding slave controller. Receive the main contactor engagement command from the controller; The controller actually connected to the main contactor executes the main contactor's engaging action; If both controllers have a fault in their precharge circuits, both controllers will report the fault.

3. The control method for the vehicle drive assembly according to claim 1, characterized in that, The master controller and slave controllers within the group perform a pre-charge handshake, specifically including: The main controller within the group sends a pre-charge preparation command to the slave controller; The controller performs a self-check of its initialization program status. If a fault is detected in its own initialization program, the fault is reported from the controller; If a fault is detected in its own initialization procedure, the slave controller replies with a ready signal to the master controller.

4. The control method for the vehicle drive assembly according to claim 1, characterized in that, The slave controller sends a confirmation signal to the corresponding master controller based on the bus voltage and pre-charge time of the circuit board, specifically including: The total pre-charge time when the controller determines that the bus voltage of the panel reaches the set voltage threshold. If the total precharge time is less than the set time, the slave controller sends a confirmation signal to the corresponding master controller. If the total precharge time is greater than or equal to the set time, the slave controller records the secondary fault flag bit and then sends a confirmation signal to the corresponding master controller.

5. The control method for the vehicle drive assembly according to claim 4, characterized in that, After the master controller and slave controllers in the group perform a pre-charge handshake, it also includes: The main controller and the slave controller synchronously detect whether a secondary positioning fault flag is recorded. If no secondary location fault flag is recorded, then the main controller and slave controller in the group shall perform synchronous pre-charging.

6. The control method for the vehicle drive assembly according to claim 5, characterized in that, Also includes: If any controller records the secondary positioning fault flag, then only the main controller will perform pre-charging; The main controller detects the bus voltage of the detection array panel; If the main controller detects that the bus voltage of the panel is greater than or equal to a set voltage threshold, the main controller will actively discharge. The main controller sends a pre-charge command to the slave controllers in the group, so that the slave controllers can pre-charge individually. The controller detects the bus voltage of the panel. If the voltage of the busbar detected by the slave controller is greater than or equal to the set voltage threshold, the slave controller will actively discharge and then perform a synchronous pre-charging step between the master controller and the slave controller in the group.

7. The control method for the vehicle drive assembly according to claim 6, characterized in that, Also includes: If the main controller detects that the bus voltage of the panel is less than the set voltage threshold, the main controller records and increases the number of pre-charge faults. The main controller determines whether the number of precharge failures recorded has reached the set number; If the number of pre-charge failures recorded by the main controller does not reach the set number, then return to the step of pre-charging only by the main controller; If the number of precharge failures recorded by the main controller reaches a set number, the main controller will perform the active discharge step.

8. The control method for the vehicle drive assembly according to claim 7, characterized in that, Also includes: If the voltage of the busbar detected by the slave controller is less than the set voltage threshold, the slave controller records and increases the number of pre-charge faults. The controller determines whether the number of precharge failures recorded has reached a set number. If the number of pre-charge failures recorded from the controller does not reach the set number, then return to the step of pre-charging only by the main controller; If the number of precharge failures recorded by the controller reaches the set number, then the step of actively discharging the controller is executed.

9. A vehicle drive assembly, characterized in that, The vehicle includes a front axle drive assembly and a rear axle drive assembly, each of which includes two controllers, one of which is connected to a power battery via a main contactor. The front axle drive assembly and the rear axle drive assembly are configured to perform the control method for the vehicle drive assembly as described in any one of claims 1-8.

10. An engineering machinery, characterized in that, Includes the vehicle drive assembly as described in claim 9.

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