Pure electric commercial vehicle multi-gear gearbox gear shifting in-loop test system and method

Abstract

The invention relates to a pure electric commercial vehicle multi-gear gearbox gear shifting in-loop test system and method, and the system comprises a tested gearbox controller which is used for executing gearbox gear shifting control according to a target gear signal; the execution mechanism entity unit is bidirectionally connected with the tested gearbox controller and is used for receiving the gear shifting control signal, executing gear shifting action and feeding back position information; the in-loop test host is used for simulating a vehicle operation environment and is bidirectionally connected with the tested gearbox controller so as to transmit simulation operation parameters and obtain gear shifting control data; the vehicle control unit is used for carrying out bidirectional data interaction with the in-loop test host, generating a target gear signal according to interaction data and sending the target gear signal to the tested gearbox controller; and the vehicle control unit is also used for receiving a gear shifting execution result fed back by the tested gearbox controller.

Description

Technical Field

[0001] This invention relates to the field of hardware-in-the-loop testing technology for gearbox shifting processes, and particularly to a hardware-in-the-loop testing system and method for multi-gear gearbox shifting in pure electric commercial vehicles. Background Technology

[0002] Due to the unique characteristics of commercial vehicles in terms of load capacity and operational complexity, single-gear pure electric transmissions are insufficient to meet the vehicle's power and fuel economy requirements. Therefore, the adoption of multi-gear pure electric transmissions has become an inevitable trend. However, the increase in transmission gears significantly increases the complexity of the controller software and the difficulty of shift control. To ensure the correctness of the software's shift logic and the safety of its application in real vehicles, the software must undergo multi-level verification, including unit testing, model-in-the-loop testing, and hardware-in-the-loop testing (HIL), before deployment.

[0003] Current hardware-in-the-loop testing systems for gearbox shifting processes have two major flaws:

[0004] Firstly, apart from the transmission controller under test, which is a physical object, the other interactive controllers (such as the vehicle controller VCU) in the system are usually implemented using virtual models. Since the virtual controller strategy model is significantly different from the real vehicle controller strategy, the test conditions are limited, the coverage is insufficient, and it is difficult to truly simulate the real vehicle interaction environment.

[0005] Secondly, most existing systems do not integrate real shift actuators, but instead simulate the shift process through mathematical or physical models. This simplified approach cannot accurately characterize the dynamic response characteristics of real shift actuators (such as position feedback accuracy and mechanical delay), resulting in significant deviations between test results and the actual vehicle shift process. This, in turn, affects the optimization of the transmission controller software and the reliability of the actual vehicle calibration.

[0006] Therefore, there is an urgent need to develop a hardware-in-the-loop testing system that is closer to the real vehicle environment to solve problems such as the mismatch between the virtual controller model and the real strategy and the distortion of the shift actuator response, thereby improving the verification accuracy and testing efficiency of multi-gear pure electric vehicle transmission controllers. Summary of the Invention

[0007] This invention discloses a loop-in-the-loop testing system and method for multi-gear transmission shifting in pure e-commerce vehicles, aiming to solve the technical problems existing in the prior art.

[0008] The present invention adopts the following technical solution:

[0009] In a first aspect, embodiments of the present invention provide a loop-in-the-loop testing system for multi-gear transmission shifting in pure electric commercial vehicles, comprising:

[0010] The transmission controller under test is used to perform transmission shift control based on the target gear signal;

[0011] The actuator unit is bidirectionally connected to the gearbox controller under test, and is used to receive shift control signals, execute shift actions, and provide feedback position information;

[0012] The in-loop test host is used to simulate the vehicle's operating environment and is bidirectionally connected to the transmission controller under test to transmit simulated operating parameters and acquire shift control data.

[0013] The vehicle controller is used for bidirectional data interaction with the in-loop test host, generating a target gear signal based on the interaction data and sending it to the transmission controller under test; the vehicle controller is also used to receive the shift execution results fed back by the transmission controller under test.

[0014] As a preferred technical solution, the actuator physical unit includes multiple independently controlled shifting motors, each of which is equipped with a position sensor to provide feedback on the actual position information of the motor;

[0015] The combined action of multiple shift actuators is used to achieve switching between different gears.

[0016] As a preferred technical solution, the loop-in test host includes at least:

[0017] A driving intention simulation unit is used to generate driving operation signals;

[0018] The powertrain simulation unit is used to simulate the working state of a vehicle's powertrain system.

[0019] The vehicle dynamics simulation unit is used to determine the vehicle's operating state parameters based on the output of the powertrain simulation unit.

[0020] Among them, the driving operation signal and the vehicle operating status parameters are transmitted to the vehicle controller in sequence to generate the target gear signal.

[0021] As a preferred technical solution, the bidirectional data interaction between the loop-in test host and the vehicle controller includes:

[0022] The driving intention simulation unit generates acceleration and braking signals that characterize driving operations and transmits them to the vehicle controller.

[0023] The vehicle controller calculates and outputs drive motor control commands based on acceleration and braking signals;

[0024] The power system simulation unit receives drive motor control commands, simulates their execution, and calculates the corresponding drive motor power output.

[0025] The vehicle dynamics simulation unit calculates vehicle operating state parameters based on the power output of the drive motor and transmits these parameters to the vehicle controller.

[0026] The vehicle controller generates the target gear signal based on the vehicle's operating status parameters and the current driving conditions.

[0027] As a preferred technical solution, the power system simulation unit is used for:

[0028] The drive motor control mode is determined based on the drive motor control commands output by the vehicle controller;

[0029] Based on the drive motor control mode, the actual torque of the drive motor is determined by the corresponding calculation logic.

[0030] The actual speed of the drive motor is calculated based on the position status of the actuator unit and the actual torque of the drive motor.

[0031] Specifically, when the actuator unit indicates that the gearbox is in the disengaged state, the drive motor speed is calculated based on the torque balance relationship; when the actuator unit indicates that the gearbox is in the engaged state, the drive motor speed is calculated based on the relationship between vehicle speed and gear ratio.

[0032] As a preferred technical solution, the drive motor control modes include:

[0033] Torque control mode, in which the actual torque of the drive motor is obtained by applying dynamic response characteristics to the target torque;

[0034] In the speed control mode, the actual torque of the drive motor is obtained by closed-loop control of the deviation between the target speed and the actual speed.

[0035] As a preferred technical solution, the separated state refers to the shifting motor in the actuator unit being in the middle position;

[0036] Engaged state refers to the shifting motor in the actuator unit being in the left or right position;

[0037] The power system simulation unit is also used to determine the working status of the gearbox in real time based on the position information of the shift actuator motor fed back by the actuator physical unit, and select the corresponding drive motor speed calculation method accordingly.

[0038] As a preferred technical solution, the vehicle dynamics simulation unit is used for:

[0039] Based on the drive motor power output from the power system simulation unit, and combined with preset vehicle driving resistance parameters, the real-time vehicle speed is calculated.

[0040] The vehicle's real-time speed is transmitted to the vehicle controller as a vehicle operating status parameter.

[0041] As a preferred technical solution, a monitoring and control unit is included, which is communicatively connected to the in-loop test host, the vehicle controller and the transmission controller under test, and is used to receive real-time operating data from the three.

[0042] The monitoring and control unit is also used to send test control commands to the in-loop test host. The test control commands include at least test condition selection, test parameter setting, and test process control.

[0043] Secondly, embodiments of the present invention provide a loop-in-the-loop testing method for a multi-gear transmission in a pure e-commerce vehicle. The method is performed using the loop-in-the-loop testing system for a multi-gear transmission in a pure e-commerce vehicle as described in any of the preceding claims, and includes the following steps:

[0044] Build a test environment and connect the vehicle controller, actuator physical units, and in-loop test host;

[0045] Based on preset test conditions, driving intentions are simulated by the loop test host, and control signals are generated;

[0046] The vehicle controller determines the target gear based on the received signal and generates a shift control signal;

[0047] The actuator unit performs the gear shifting operation and feeds back status information;

[0048] The in-loop test host adjusts the simulation calculations based on the status information and continues testing.

[0049] One embodiment of the above invention has the following advantages or beneficial effects:

[0050] This invention provides a closed-loop testing system and method for multi-gear transmission shifting in pure electric commercial vehicles. By constructing a closed-loop testing environment that includes the transmission controller under test, actuator physical units, a test host, and the vehicle controller, efficient testing of the shifting process of multi-gear transmissions in pure electric commercial vehicles is achieved. This system combines software simulation with hardware physical components, preserving the actual physical characteristics of the actuators while simulating the vehicle's operating environment through software, effectively solving the problem that traditional bench testing cannot comprehensively simulate the dynamic operating conditions of vehicles.

[0051] Specifically, the in-loop test host achieves comprehensive simulation of driving operation, power system response, and vehicle operating status through driving intention simulation unit, power system simulation unit, and vehicle dynamics simulation unit. In particular, the power system simulation unit can flexibly switch the drive motor speed calculation method according to the position status of the actuator physical unit, accurately simulate the different power transmission characteristics of the gearbox in the disengaged and engaged states, and improve the realism and accuracy of the test.

[0052] Furthermore, the monitoring and control unit equipped in this system enables comprehensive monitoring and control of the testing process. It can receive real-time system operating data and send test control commands, facilitating test personnel to adjust test parameters and operating conditions. This hardware-software integrated testing solution not only reduces testing costs and shortens the testing cycle, but also safely verifies the effectiveness and reliability of the transmission shifting strategy in a laboratory environment, providing strong support for the development and optimization of transmission control strategies for pure electric commercial vehicles.

[0053] Compared with traditional methods, this invention can reproduce shifting scenarios under various complex working conditions in the laboratory, avoiding the high cost and uncertainty of road testing. At the same time, by retaining the real response characteristics of key hardware components through the physical unit of the actuator, it solves the defect that pure software simulation cannot accurately reflect the dynamic characteristics of the physical actuator, and achieves an organic unity of testing efficiency and testing authenticity. Attached Figure Description

[0054] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below, forming part of the present invention. The illustrative embodiments of the present invention and their descriptions explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0055] Figure 1 This is a structural block diagram of a loop-in-the-loop testing system for a multi-gear transmission in a pure electric vehicle, provided in one embodiment of the present invention.

[0056] Figure 2 This is a schematic flowchart of a loop-in-the-loop testing method for a multi-gear transmission in a pure e-commerce vehicle according to an embodiment of the present invention.

[0057] Figure 3 This is a structural block diagram of a five-speed transmission shift-in-the-loop test system for pure e-commerce vehicles provided in one embodiment of the present invention;

[0058] Figure 4 This is a schematic diagram of the actual structure of a five-speed transmission for pure e-commerce vehicles provided in one embodiment of the present invention. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. In the description of this invention, it should be noted that the term "or" is generally used to include the meaning of "and / or," unless otherwise expressly indicated.

[0060] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0061] refer to Figure 1 To address the shortcomings of existing technologies, this invention provides a loop-in-the-loop testing system for multi-gear transmissions in pure electric vehicles in a preferred embodiment. In this embodiment, pure electric vehicles include, but are not limited to, electric trucks, electric logistics vehicles, electric buses, and electric transport vehicles.

[0062] In a preferred embodiment, the system includes at least a transmission under test (TUT) controller 10, an actuator entity unit 20, an in-loop test host 30, and a vehicle controller 40. The TUT controller 10 executes transmission shift control based on a target gear signal. The actuator entity unit 20 is bidirectionally connected to the TUT controller 10, receiving shift control signals, executing shift actions, and providing feedback position information. The in-loop test host 30 simulates the vehicle's operating environment and is bidirectionally connected to the TUT controller 10 to transmit simulated operating parameters and acquire shift control data. The vehicle controller 40 interacts bidirectionally with the in-loop test host 30, generates a target gear signal based on the interaction data, and sends it to the TUT controller 10. Preferably, the vehicle controller 40 also receives shift execution results from the TUT controller 10.

[0063] In a preferred embodiment, the system further includes a monitoring and control unit 50, which is communicatively connected to the in-loop test host 30 and the vehicle controller 40 to receive real-time operating data from both. Preferably, the monitoring and control unit 50 is also used to send test control instructions to the in-loop test host 30, the test control instructions including at least test condition selection, test parameter setting, and test process control.

[0064] Preferably, the transmission controller 10 under test in this embodiment is a transmission control unit (TCU), which is one of the core control components of this system. The transmission controller 10 under test can receive the target gear signal from the vehicle controller 40 and generate corresponding shift execution commands based on the built-in shift control algorithm. The transmission controller has real-time processing capabilities and can accurately control the action sequence and timing of the actuator physical unit 20 according to the requirements of the target gear to achieve smooth and efficient gear shifting. Preferably, the controller is also equipped with fault diagnosis and protection functions, which can react in a timely manner when abnormal conditions are detected to ensure the safe operation of the system.

[0065] Preferably, the actuator unit 20 executes the shift commands issued by the transmission controller 10 under test. This unit includes multiple independently controlled shift actuator motors, each equipped with a position sensor for real-time feedback of the motor's actual position information. Preferably, the multiple shift actuator motors can switch between different gears through combined actions. In this embodiment, the actuator unit 20 and the transmission controller 10 under test have bidirectional communication, enabling it to not only receive control signals and execute corresponding actions, but also to feed back the status information during the execution process to the controller in real time, forming a closed-loop control.

[0066] Preferably, the HIL (Hardware-in-the-Loop) test host 30 is the core simulation platform of the entire test system, used to simulate various operating conditions in the actual vehicle operating environment, and integrates multiple functional units. Preferably, the HIL test host 30 is a simulation platform built in the Matlab / Simulink environment, where each functional unit corresponds to a corresponding HIL test model. Preferably, the HIL test host 30 can generate corresponding driving operation signals according to preset test conditions, simulate the power output characteristics of the drive motor, and calculate vehicle operating state parameters. These simulation data interact in real time with the transmission controller 10 under test and the vehicle controller 40, constructing a complete closed-loop test environment.

[0067] Preferably, in this embodiment, the vehicle controller 40 is a vehicle control unit (VCU). The vehicle controller 40 is mainly responsible for comprehensively analyzing the vehicle's operating status and driving intentions to generate an appropriate target gear signal. Preferably, a two-way data interaction mechanism is established between the vehicle controller 40 and the on-loop test host 30. The vehicle controller 40 receives driving operation signals and vehicle operating status parameters from the test host and determines the optimal gear based on this information. At the same time, the vehicle controller 40 also receives the shift execution results fed back by the transmission controller 10 under test, which are used to evaluate the shift quality and adjust the control strategy.

[0068] Preferably, the monitoring and control unit 50 is the host computer in the system, serving as the human-machine interface for the entire testing system and providing testers with a convenient operation and monitoring platform. Preferably, this host computer establishes connections with the in-loop test host 30, the vehicle controller 40, and the transmission controller 10 under test via communication interfaces, enabling it to receive and display real-time operating data from various parts of the system, including shift status, drive motor operating parameters, vehicle speed, and other key information. Preferably, the monitoring and control unit 50 can send test control commands to the in-loop test host 30. These commands include, but are not limited to, test condition selection, test parameter setting, and test process control, allowing testers to flexibly adjust test conditions. Furthermore, this host computer also has data recording, storage, and analysis functions, enabling comprehensive recording of the entire testing process and processing and analyzing the collected data to generate test reports and charts, providing intuitive data support for the evaluation and optimization of transmission control strategies.

[0069] In a preferred embodiment, the in-loop test host 30 includes at least a driving intention simulation unit, a powertrain simulation unit, and a vehicle dynamics simulation unit. Each functional unit corresponds to a corresponding HIL test model, and these HIL test models can be compiled and downloaded to the real-time machine for execution.

[0070] Preferably, the driving intention simulation unit includes a driver model that can generate driving operation signals to simulate the operating behavior of a real driver.

[0071] Preferably, the powertrain simulation unit includes a motor controller model and a motor model, used to simulate the operating characteristics of the powertrain system of a pure electric commercial vehicle. Preferably, this unit can determine the control mode of the drive motor based on the drive motor control commands output by the vehicle controller 40, and use corresponding calculation logic to determine the actual torque output of the drive motor.

[0072] In a preferred embodiment, the power system simulation unit can simulate the power output characteristics of the drive motor. The unit first determines the drive motor control mode, including torque control mode and speed control mode, based on the drive motor control command output by the vehicle controller 40. Then, based on different drive motor control modes, it uses corresponding calculation logic to determine the actual torque output of the drive motor, thereby achieving accurate simulation of the motor's power characteristics.

[0073] Preferably, in torque control mode, the powertrain simulation unit calculates the actual torque of the drive motor by applying dynamic response characteristics (such as response time and torque rise rate limits) to the target torque issued by the vehicle controller 40. This calculation method can simulate the dynamic response lag and limitations present in real motor systems, improving the realism of the simulation. In speed control mode, the powertrain simulation unit compares the deviation between the target speed and the actual speed, and performs closed-loop control calculations in conjunction with preset control parameters (such as proportional gain, integral gain, etc.) to obtain the actual torque that the motor needs to output, thereby achieving accurate simulation of the speed control process.

[0074] Furthermore, the power system simulation unit calculates the actual speed of the drive motor based on the position state of the actuator entity unit 20 and the actual torque of the drive motor; wherein, when the actuator entity unit 20 indicates that the gearbox is in the disengaged state, the drive motor speed is calculated based on the torque balance relationship; when the actuator entity unit 20 indicates that the gearbox is in the engaged state, the drive motor speed is calculated based on the relationship between vehicle speed and gear ratio.

[0075] Specifically, the separated state refers to the shifting motor in the actuator unit 20 being in the middle position. At this time, factors such as motor output torque, motor rotational inertia, and frictional resistance are mainly considered to simulate the speed change of the drive motor under no-load conditions. The engaged state refers to the shifting motor in the actuator unit 20 being in the left or right position. In the engaged state, since a definite mechanical connection is established between the drive motor and the wheel, there is a clear gear ratio relationship between the motor speed and the vehicle speed. Therefore, the actual speed of the drive motor can be calculated by back-calculating based on the current vehicle speed and the gear ratio corresponding to the gearbox.

[0076] Preferably, the power system simulation unit determines the working status of the gearbox in real time based on the position information of the shift actuator motor fed back by the actuator entity unit 20, and selects the corresponding drive motor speed calculation method accordingly.

[0077] Specifically, the torque and speed of a drive motor influence and constrain each other. In an electric vehicle powertrain system, under a given motor power limit, torque and speed are inversely proportional; that is, as the speed increases, the maximum output torque decreases; conversely, when a larger torque is required, the maximum achievable speed is also limited. By simultaneously simulating these two parameters, the powertrain simulation unit can accurately reflect the operating characteristics and physical constraints of a real motor, ensuring the authenticity and reliability of the test environment.

[0078] Preferably, the vehicle dynamics simulation unit includes a transmission actual gear position calculation model, an oil pump model, and a vehicle dynamics model, used to calculate the vehicle's operating state based on the power parameters output by the power system. Preferably, this unit can calculate the vehicle's real-time speed and other operating parameters based on the power output of the drive motor and preset vehicle parameters.

[0079] In a preferred embodiment, the vehicle dynamics simulation unit can calculate the real-time vehicle speed based on the drive motor power output of the power system simulation unit and in combination with preset vehicle driving resistance parameters; and transmit the real-time vehicle speed as a vehicle operating status parameter to the vehicle controller 40.

[0080] Specifically, the vehicle dynamics simulation unit can take the actual torque output by the drive motor as input, and convert it through the gear ratio and transmission efficiency corresponding to the current gear of the gearbox to obtain the driving force acting on the wheels; preferably, the vehicle driving resistance parameters include, but are not limited to, vehicle mass, drag coefficient, frontal area, rolling resistance coefficient, road slope, etc. These parameters can be precisely set according to the characteristics of different vehicle models to ensure the accuracy of the simulation.

[0081] In one optional implementation, the vehicle dynamics simulation unit can use a time-domain integration method to calculate the vehicle's real-time speed. This involves dividing the resultant force of the vehicle's driving force and resistance at the current moment by the vehicle's equivalent mass to obtain the vehicle's acceleration; then integrating the acceleration in the time domain to obtain the speed increment; and finally adding the speed increment to the speed at the previous moment to obtain the current real-time vehicle speed. This calculation method can accurately reflect the vehicle's dynamic response characteristics under various operating conditions, including different driving stages such as acceleration, cruising, and deceleration.

[0082] In a preferred embodiment, the in-loop test host 30 is further provided with a CAN signal transceiver model and a hard-wired signal transceiver model. The vehicle operating state parameters calculated by the vehicle dynamics simulation unit are transmitted to the vehicle controller 40 through the CAN signal transceiver model and the hard-wired signal transceiver model to provide necessary input information for gear shifting decisions.

[0083] Specifically, the embodiments of the present invention do not specifically limit the specific content, parameter settings, and internal algorithm implementation of each model. Those skilled in the art can flexibly construct the internal structure of each functional module according to actual testing needs and the characteristics of the system under test. Preferably, in practical applications, the above models can be specifically adjusted and optimized according to the characteristic parameters of different vehicle models, driving scenario requirements, and testing objectives to meet the testing needs of multi-gear transmissions in specific pure electric commercial vehicles. At the same time, the interface definitions and data exchange formats between the models should be consistent to ensure the coordinated operation of the entire testing system.

[0084] Preferably, the driving operation signal and vehicle operating status parameters are transmitted to the vehicle controller 40 in sequence. After receiving the vehicle speed information, the vehicle controller 40, in combination with other operating parameters (such as driver intention, drive motor speed, etc.), can make an accurate gear shifting decision and generate a suitable target gear signal.

[0085] In a preferred embodiment, the bidirectional data interaction between the in-loop test host 30 and the vehicle controller 40 constitutes a complete closed-loop control system, ensuring accurate simulation of the actual vehicle operating conditions in the test environment. This interaction process is first triggered by the driving intention simulation unit, which generates acceleration and braking signals simulating driver operation based on preset test conditions. These signals are transmitted to the vehicle controller 40 through a defined interface, simulating driver input in a real driving environment. Preferably, the acceleration signal is typically represented as the accelerator pedal opening percentage, and the braking signal is represented as the brake pedal force or travel percentage, to accurately simulate different driving styles and operating intentions.

[0086] After receiving the driving intention signal, the vehicle controller 40 calculates and outputs corresponding drive motor control commands based on its internal control strategy and algorithm. These commands may include torque control commands or speed control commands, depending on the current vehicle operating state and control mode. Upon receiving these control commands, the powertrain simulation unit simulates their execution using its internal motor and motor controller models, and calculates the drive motor power output, including actual output torque and speed, consistent with the actual motor behavior.

[0087] The vehicle dynamics simulation unit receives drive motor power output data from the powertrain simulation unit. Combining this data with the current transmission status and preset vehicle parameters, it calculates real-time vehicle operating parameters, such as vehicle speed and acceleration. These calculated parameters are then transmitted back to the vehicle controller 40, completing the closed-loop data exchange. Based on the received vehicle operating parameters and the current driving conditions, such as acceleration, cruising, and hill climbing, the vehicle controller 40 evaluates whether the current gear is optimal and generates a new target gear signal when necessary.

[0088] Through the aforementioned two-way data interaction mechanism, the entire testing system can simulate the dynamic response process of a real vehicle under various driving conditions. Furthermore, the closed-loop design allows the testing system to comprehensively evaluate the shifting decision-making and execution performance of the transmission controller under different operating conditions, including the rationality of shift timing, the smoothness of the shifting process, and the response speed to driving intentions—key indicators. Simultaneously, this simulation method avoids the high costs and potential risks of real-vehicle testing, providing an efficient and reliable testing platform for the development and optimization of multi-gear transmissions in pure electric commercial vehicles.

[0089] refer to Figure 1 and Figure 2 Based on the above-mentioned loop-in-the-loop testing system for multi-gear transmissions in pure e-commerce vehicles, an embodiment of the present invention also provides a loop-in-the-loop testing method for multi-gear transmissions in pure e-commerce vehicles, the method preferably including the following steps:

[0090] Step S610: Build the test environment by connecting the vehicle controller 40, the actuator entity unit 20, and the in-loop test host 30.

[0091] Preferably, constructing the test environment is fundamental to the entire testing process. First, the vehicle controller 40, actuator unit 20, and in-loop test host 30 need to be physically connected according to a predetermined topology. Specifically, the vehicle controller 40 establishes a communication connection with the in-loop test host 30 via a CAN bus to receive simulated driving intention signals and vehicle operating status parameters. Simultaneously, the vehicle controller 40 connects to the transmission controller under test 10 via another CAN bus or hardwired signal to transmit the target gear signal. The actuator unit 20 is directly connected to the transmission controller under test 10, forming a control loop. Furthermore, a monitoring and control unit 50 needs to be configured to connect with the in-loop test host 30, vehicle controller 40, and transmission controller under test 10 for control and data monitoring during the testing process. After completing the hardware connection, each system needs to be initialized to ensure normal communication and that each unit is in standby mode.

[0092] Step S620: Based on preset test conditions, driving intentions are simulated by the loop test host 30, and control signals are generated.

[0093] Preferably, the loop-in-the-loop test host 30 generates corresponding driving operation signals through the driving intention simulation unit according to pre-set test conditions. Preferably, the test conditions may include, but are not limited to, urban conditions, highway conditions, hill climbing conditions, and frequent acceleration and deceleration conditions, covering various driving scenarios that pure electric commercial vehicles may encounter in actual use. The driving intention simulation unit generates time-varying acceleration and braking signals according to the selected conditions, and these signals are transmitted to the vehicle controller 40 through a predefined interface. At the same time, the powertrain simulation unit and vehicle dynamics simulation unit inside the loop-in-the-loop test host 30 also enter working state, ready to receive subsequent control commands and perform corresponding simulation calculations.

[0094] In step S630, the vehicle controller 40 determines the target gear based on the received signal and generates a shift control signal.

[0095] Preferably, after receiving driving operation signals and vehicle operating status parameters from the on-loop test host 30, the vehicle controller 40 performs comprehensive analysis and decision-making based on its internal control strategy and algorithm. Preferably, the vehicle controller 40 first calculates the driving demand under the current operating condition based on acceleration and braking signals, combined with current vehicle speed, load, and other status parameters; then, based on the matching degree between the driving demand and the current gear, it determines whether a gear shift is needed; if a gear shift is needed, it further determines the target gear and generates the corresponding gear shift control signal. These signals are transmitted to the transmission controller 10 under test through a preset interface, triggering subsequent gear shift operations. Simultaneously, the vehicle controller 40 also generates drive motor control commands, which are returned to the powertrain simulation unit through the on-loop test host 30, forming a closed-loop control.

[0096] In step S640, the actuator entity unit 20 performs a gear shifting operation and provides feedback on the status information.

[0097] Preferably, after receiving the target gear signal from the vehicle controller 40, the transmission controller 10 under test generates detailed shift execution instructions based on its internal shift control algorithm and sends them to the actuator unit 20. Upon receiving these instructions, the shift execution motor in the actuator unit 20 executes the corresponding actions according to a predetermined sequence and timing to achieve gear switching. Preferably, the position sensor configured in the actuator unit 20 monitors the position status of the shift execution motor in real time and feeds this status information back to the transmission controller 10 under test and the in-loop test host 30. This feedback information includes, but is not limited to, the motor's current position, speed, and time to reach a specific position, comprehensively reflecting the actual situation of shift execution and providing data support for subsequent analysis and optimization.

[0098] In step S650, the loop-in test host 30 adjusts the simulation calculation based on the status information and continues the test.

[0099] After receiving the status information from the actuator entity unit 20, the on-loop test host 30 dynamically adjusts the calculation parameters and logic of its internal model based on this information. Preferably, the powertrain simulation unit determines in real time whether the gearbox is in a disengaged or engaged state based on the position status of the shift actuator motor, and selects the appropriate drive motor speed calculation method accordingly; the vehicle dynamics simulation unit adjusts the simulation calculation of the power transmission path based on the gearbox status and the current gear, ensuring that the output vehicle operating status parameters are consistent with the actual situation. After the adjustment is completed, the test system continues to run, continuously generating new driving intention signals according to the preset test conditions, driving the entire test process forward until all test items are completed or the preset test duration is reached.

[0100] Specifically, the shift-in-the-loop testing method for multi-gear transmissions in pure electric commercial vehicles provided in this embodiment belongs to the same inventive concept as the testing system described in the previous embodiments, and is a specific explanation of the workflow and usage of that testing system. The composition, connection relationships, and working principles of the functional units already described in the previous embodiments are naturally inherited in this embodiment and will not be repeated. This embodiment further clarifies the collaborative working methods and data interaction mechanisms of each unit during the testing process by decomposing the testing process into a clear sequence of steps, making the testing method more systematic and operable, and helping testers to efficiently conduct shift performance testing of multi-gear transmissions in pure electric commercial vehicles.

[0101] refer to Figure 3 In one specific embodiment of the present invention, a loop-in-the-loop testing system for a five-speed transmission in a pure electric commercial vehicle is provided. This system simulates the structure of a five-speed transmission driven by a dual-motor system for testing, such as... Figure 4 By integrating real vehicle controllers and gear shift actuator physical units, it is possible to achieve high-precision simulation testing of complex gear shifting conditions.

[0102] In a preferred embodiment, the dual-motor driven five-speed gearbox structure simulated by the test system includes a parallel-arranged drive motor 1 and drive motor 2, each connected to a gearbox gear set via an input shaft. Preferably, the gearbox gear set includes a shift actuator motor 1, a shift actuator motor 2, and a shift actuator motor 3, with the three shift actuator motors controlling the gear meshing state via mechanical shift forks. Specifically, shift actuator motor 1 drives a first shift fork, controlling the power transmission path between the input shaft of drive motor 1 and the wheel; shift actuator motor 2 drives a second shift fork; and shift actuator motor 3 drives a third shift fork. The second and third shift forks control the power transmission path between the input shaft of drive motor 2 and the wheel; the three shift forks coordinate the power coupling and decoupling of the two motors. This gearbox, through independent dual-motor drive and a three-shift fork linkage mechanism, can achieve five-speed switching, while providing a clear physical mapping relationship for hardware-in-the-loop testing of the shifting process. In this embodiment, the specific positions and power flow directions of the three shift forks in each gear are not specifically defined.

[0103] In a preferred embodiment, the system includes a five-speed gearbox controller, an actuator physical unit, a vehicle controller, a hardware-in-the-loop master bench, and a host computer. The actuator physical unit includes three shift actuator motors.

[0104] Preferably, the five-speed gearbox controller establishes a bidirectional connection with the hardware-in-the-loop main test bench via the power CAN, proprietary CAN, and I / O hardwire. The power CAN is used to transmit motor control signals (such as target torque and speed), the proprietary CAN is used to transmit oil pump operating status signals, and the I / O hardwire is used to transmit critical hardwire signals (such as KL15 power supply, oil pump temperature, and intermediate shaft / output shaft speed). In particular, the five-speed gearbox controller has a built-in H-bridge drive circuit that is directly electrically connected to the three shift actuator motors in the actuator unit, used to output shift control pulse signals and drive the motors to perform shift actions.

[0105] Preferably, the actuator unit includes shift motor 1, shift motor 2, and shift motor 3, which are independently controlled. Each shift motor is equipped with a position sensor. Specifically, the position sensor output voltage range is 0-5V: when the output voltage is 2.5V, it indicates that the shift motor is in the middle position, i.e., the disengaged state; when the output voltage is <1V, it indicates that the shift motor is in the left position, i.e., the engaged state; and when the output voltage is >4V, it indicates that the shift motor is in the right position, i.e., the engaged state. Preferably, the feedback signal from the position sensor is transmitted to the five-speed gearbox controller in real time, forming a closed-loop control: the five-speed gearbox controller dynamically adjusts the output pulse width and direction of the H-bridge circuit according to the feedback signal to ensure that the shift motor accurately reaches the target position. The combined action of the three shift motors achieves the switching of five gears through shift fork control, such as... Figure 4 As shown.

[0106] Preferably, the hardware-in-the-loop main test bench includes a real-time machine, a bus, and I / O boards. The real-time machine stores HIL test models, including a driver model, a motor controller model, a dual-motor model, a gearbox actual gear position calculation model, an oil pump model, a vehicle dynamics model, a CAN signal transceiver model, and a hardwired signal transceiver model.

[0107] In a preferred embodiment, the driver model generates acceleration / braking signals based on preset test conditions (such as constant throttle, constant speed, or driving cycle conditions), and converts these signals into voltage signals via an analog board, which are then output to the vehicle controller. The motor controller model and the dual-motor model are used to calculate the actual torque, speed, and operating mode according to instructions from the vehicle controller and send these parameters to the vehicle controller; wherein, the dual-motor model refers to… Figure 4 The system includes drive motor 1 and drive motor 2. The actual gearbox gear calculation model calculates the actual gear and speed ratio in real time based on the position and voltage values ​​of the shift actuator motors. The vehicle dynamics model calculates the real-time vehicle speed based on the motor output torque and driving resistance parameters.

[0108] Preferably, the CAN signal transceiver model and the hardwired signal transceiver model achieve signal interaction with external hardware through the CAN bus and I / O board.

[0109] In a preferred embodiment, the vehicle control unit (VCU) serves as the actual hardware access system, establishing a bidirectional connection with the five-speed transmission controller and the hardware-in-the-loop master bench via the powertrain CAN bus. Preferably, the VCU receives accelerator / brake pedal opening signals generated by the driving intention simulation unit, calculates the requested target torque, speed, and operating mode of the drive motor in real time during gear shifting, and transmits this information to the powertrain simulation unit (i.e., the motor controller model and the dual-motor model) via the powertrain CAN bus. Furthermore, the VCU also determines the target gear based on vehicle operating status parameters such as vehicle speed and transmits this information to the five-speed transmission controller via the powertrain CAN bus.

[0110] In a preferred embodiment, the host computer connects to the hardware-in-the-loop master test bench via Ethernet, providing a human-machine interface. Preferably, the host computer supports test condition selection and HIL test model parameter settings, and monitors the power CAN / private CAN bus signals in real time. Specifically, the host computer also calibrates and records the internal signals of the five-speed transmission controller via CAN diagnostics.

[0111] Preferably, the monitoring and control unit integrates a CAN signal monitoring device, which is connected in parallel to the power CAN bus and the private CAN bus through a physical interface to collect the interactive signals on the bus in real time.

[0112] Preferably, the host computer acquires the interactive signals on the power CAN bus in real time via a CAN signal measurement device (including motor parameters requested by the five-speed transmission controller, vehicle controller commands, and actual drive motor parameters output by the HIL test model), and performs online calibration and parameter adjustment of the internal signals of the five-speed transmission controller through diagnostic CAN using INCA software. During the shift test, testers can comprehensively compare the shift execution motor position voltage signal, motor controller signal, transmission controller internal calibration and observation signals, and vehicle controller decision signals to verify the correctness and execution accuracy of the shift logic from multiple dimensions.

[0113] In a preferred embodiment, the core function of the motor controller model and the dual-motor model is to dynamically calculate the speed and torque of the drive motor based on the gearbox status.

[0114] Preferably, when the motor control mode issued by the vehicle controller is torque control mode, the actual torque of the two drive motors is obtained through a delay circuit; when the motor control mode issued by the vehicle controller is speed control mode, the actual torque of the two drive motors is obtained by adjusting the difference between the target speed and the actual speed of the drive motors through a PID controller.

[0115] Preferably, when the shift actuator motor 1 is in the intermediate position, i.e., the disengaged state, the speed of the drive motor 1 satisfies the following relationship:

[0116]

[0117] Where J1 is the moment of inertia of drive motor 1, and ω1 is initially the rotational speed of drive motor 1 before the shift motor moves to the middle position.

[0118] Preferably, when the shift execution motor 1 is in the left / right position, i.e. in the engaged state, the speed of the drive motor 1 is coupled with the vehicle speed, which can be calculated from the vehicle speed.

[0119] Preferably, if either the shift actuator motor 2 or the shift actuator motor 3 is in the intermediate position, then the rotational speed of the drive motor 2 is:

[0120]

[0121] Where J2 is the moment of inertia of drive motor 2, and ω2 is initially the rotational speed of drive motor 2 before the shift motor moves to the middle position.

[0122] Preferably, when both the shift actuator motor 2 and the shift actuator motor 3 are in the left / right position, i.e., in the engaged state, the speed of the drive motor 2 is coupled with the vehicle speed, which can be calculated from the vehicle speed.

[0123] In a preferred embodiment, the system closed-loop testing process includes: the driver model generates acceleration / braking signals, which are converted into voltage signals by a simulation board and transmitted to the vehicle controller; the vehicle controller calculates the target torque / speed of the drive motor based on the driving intention and real-time vehicle speed, and sends it to the motor controller model and the dual-motor model via the power CAN bus; the motor controller model and the dual-motor model select the speed calculation logic corresponding to the separation / engagement state according to the position status of the shift execution motor fed back by the transmission controller under test, and output the actual motor torque / speed to the vehicle dynamics model; the vehicle dynamics model calculates the real-time vehicle speed in combination with the driving resistance parameters and feeds it back to the vehicle controller; the vehicle controller generates a target gear signal based on the vehicle speed to trigger the five-speed transmission controller; the five-speed transmission controller drives the shift execution motor through the H-bridge circuit, and simultaneously adjusts the control output in real time according to the feedback signal from the position sensor, and sends the drive motor parameters requested during the shifting process to the vehicle controller via the power CAN bus; the host computer synchronously collects multi-source signals and performs joint analysis to complete the full-dimensional verification of the shifting process.

[0124] Compared with existing technologies, this embodiment significantly improves the realism of the test by integrating a real vehicle controller with the physical actuator unit. Specifically, the decision logic of the real vehicle controller can reproduce complex operating conditions such as hill climbing and frequent acceleration and deceleration, solving the problem of virtual controller strategy distortion; the dynamic characteristics such as mechanical delay and position accuracy of the shift actuator motor are realistically preserved, overcoming the defects of physical response distortion; and for the dual-motor structure of the five-speed gearbox (… Figure 4 Customized speed calculation logic ensures that the power transmission characteristics are consistent with those of the actual vehicle. Specifically, through the direct drive mechanism of the H-bridge circuit and position feedback closed-loop control, high-precision dynamic adjustment of gear shift execution is achieved; while the collaborative monitoring mechanism of multi-source signals (transmission controller output signal, gear shift execution motor position voltage feedback signal, vehicle controller output signal, and test model output signal) provides a complete data foundation for iterative optimization of the gear shift logic. The system provided in this embodiment achieves comprehensive verification of the gear shift strategy of a dual-motor five-speed transmission in a laboratory environment, providing highly reliable data support for real-vehicle calibration.

[0125] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

[0126] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0127] Similarly, it should be understood that, in order to streamline this application and aid in understanding one or more of the various inventive aspects, features of this application may sometimes be grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of this application. However, this approach should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, its inventive point lies in solving the corresponding technical problem with features fewer than all features of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0128] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or elements of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose.

[0129] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of the present invention.

Claims

1. A loop-in-the-loop testing system for multi-gear transmission shifting in pure e-commerce vehicles, characterized in that, include: The transmission controller under test is used to perform transmission shift control based on the target gear signal; The actuator unit is bidirectionally connected to the gearbox controller under test, and is used to receive shift control signals, execute shift actions, and provide feedback position information; The in-loop test host is used to simulate the vehicle operating environment and is bidirectionally connected to the transmission controller under test to transmit simulated operating parameters and acquire shift control data. The vehicle controller is used to perform bidirectional data interaction with the in-loop test host, generate the target gear signal based on the interaction data, and send it to the transmission controller under test; the vehicle controller is also used to receive the shift execution result fed back by the transmission controller under test.

2. The loop-in-the-loop testing system for multi-gear transmission shifting in pure e-commerce commercial vehicles according to claim 1, characterized in that, The actuator unit includes multiple independently controlled shifting motors, each of which is equipped with a position sensor to provide feedback on the motor's actual position information. The combined action of multiple shifting actuators is used to achieve switching between different gears.

3. The loop-in-the-loop testing system for multi-gear transmissions in pure e-commerce commercial vehicles according to claim 2, characterized in that, The in-loop test host includes at least: A driving intention simulation unit is used to generate driving operation signals; The powertrain simulation unit is used to simulate the working state of a vehicle's powertrain system. The vehicle dynamics simulation unit is used to determine the vehicle operating state parameters based on the output of the powertrain simulation unit; The driving operation signal and the vehicle operating status parameters are transmitted to the vehicle controller in sequence to generate the target gear signal.

4. The pure e-commerce vehicle multi-gear transmission shift-in-the-loop test system according to claim 3, characterized in that, The bidirectional data interaction between the in-loop test host and the vehicle controller includes: The driving intention simulation unit generates acceleration and braking signals that characterize driving operations and transmits them to the vehicle controller. The vehicle controller calculates and outputs drive motor control commands based on the acceleration and braking signals; The power system simulation unit receives the drive motor control command, simulates its execution, and calculates the corresponding drive motor power output. The vehicle dynamics simulation unit calculates vehicle operating state parameters based on the power output of the drive motor, and transmits the vehicle operating state parameters to the vehicle controller. The vehicle controller generates the target gear signal based on the vehicle operating status parameters and the current driving conditions.

5. The loop-in-the-loop testing system for multi-gear transmission shifting in pure e-commerce vehicles according to claim 4, characterized in that, The power system simulation unit is used for: The drive motor control mode is determined based on the drive motor control commands output by the vehicle controller. Based on the drive motor control mode, the actual torque of the drive motor is determined using the corresponding calculation logic. The actual speed of the drive motor is calculated based on the position state of the actuator unit and the actual torque of the drive motor. When the actuator entity unit indicates that the gearbox is in a disengaged state, the drive motor speed is calculated based on the torque balance relationship; When the actuator entity unit indicates that the gearbox is engaged, the drive motor speed is calculated based on the relationship between vehicle speed and gear ratio.

6. The loop-in-the-loop testing system for multi-gear transmission shifting in pure e-commerce vehicles according to claim 5, characterized in that, The drive motor control modes include: Torque control mode, wherein the actual torque of the drive motor is obtained by applying dynamic response characteristics to the target torque; In the speed control mode, the actual torque of the drive motor is obtained by closed-loop control of the deviation between the target speed and the actual speed.

7. The pure e-commerce vehicle multi-gear transmission shift-in-the-loop test system according to claim 5, characterized in that, The separation state refers to the shifting motor in the actuator unit being in the middle position; The engagement state refers to the shifting motor in the actuator unit being in the left or right position; The power system simulation unit is also used to determine the working status of the gearbox in real time based on the position information of the shift actuator motor fed back by the actuator entity unit, and select the corresponding drive motor speed calculation method accordingly.

8. The loop-in-the-loop testing system for multi-gear transmissions in pure electric commercial vehicles according to claim 5, characterized in that, The vehicle dynamics simulation unit is used for: Based on the drive motor power output from the power system simulation unit, and combined with the preset vehicle driving resistance parameters, the real-time vehicle speed is calculated. The vehicle's real-time speed is transmitted to the vehicle controller as a vehicle operating status parameter.

9. The loop-in-the-loop testing system for multi-gear transmissions in pure e-commerce commercial vehicles according to claim 1, characterized in that, It includes a monitoring and control unit, which is communicatively connected to the in-loop test host, the vehicle controller and the transmission controller under test, and is used to receive real-time operating data from the three. The monitoring and control unit is also used to send test control instructions to the in-loop test host, the test control instructions including at least test condition selection, test parameter setting and test process control.

10. A loop-in-the-loop testing method for multi-gear transmissions in pure e-commerce vehicles, characterized in that, The method is performed using the loop-in-the-loop testing system for multi-gear transmission shifting in pure electric commercial vehicles as described in any one of claims 1 to 9, and includes the following steps: Build a test environment and connect the vehicle controller, actuator physical units, and in-loop test host; Based on preset test conditions, driving intentions are simulated by the loop test host, and control signals are generated; The vehicle controller determines the target gear based on the received signal and generates a shift control signal; The actuator unit performs the gear shifting operation and feeds back status information; The in-loop test host adjusts the simulation calculations based on the status information and continues testing.

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