Multi-scene-oriented hybrid power system torque test and model calibration method and device

Abstract

The invention relates to the technical field of hybrid electric vehicle testing, in particular to a multi-scene-oriented hybrid power system torque testing and model calibration method and device. Comprises: testing a hybrid power system; the power assembly rack comprises at least one load dynamometer; a plurality of torque sensors; a rotation speed sensor; a data acquisition system; and the scene simulation equipment is used for simulating at least one test scene of the environment temperature, the altitude and the battery SOC. According to the invention, scene simulation equipment is integrated; various actual operation scenes such as high and low temperatures and different battery SOC (State of Charge) can be simulated in a laboratory environment, and direct, real-time and synchronous measurement of output torques of an engine, a motor and a wheel end is realized by combining a power assembly rack with a high-precision torque and rotating speed sensor; and the problems of poor working condition reproducibility, uncontrollable environmental conditions, low data consistency and the like in the real vehicle road test are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of hybrid vehicle testing technology, specifically to a method and apparatus for torque testing and model calibration of hybrid systems for multiple scenarios. Background Technology

[0002] Hybrid electric vehicles (HEVs), as a key technological solution for the transition from traditional internal combustion engine vehicles to pure electric vehicles, have become a major focus of the current automotive industry due to their combination of the long driving range of gasoline vehicles and the low emissions of pure electric vehicles. A hybrid system typically includes key components such as an engine, a drive motor, and a hybrid coupling transmission. The precise control and dynamic coordination of its torque output directly affect the vehicle's power performance, fuel economy, and driving quality.

[0003] Currently, the testing and evaluation of torque characteristics of hybrid power systems mostly employs real-vehicle road tests or indirectly obtains torque parameters by reading controller signals on a test bench. However, real-vehicle road tests suffer from poor reproducibility of test conditions, uncontrollable environmental conditions, long test cycles, and low safety, making it difficult to systematically obtain accurate torque data under multiple scenarios. In bench tests, indirect measurement methods relying on controller signals (such as VCU torque requests) are often affected by factors such as signal transmission delays, sensor accuracy, and system calibration errors. The obtained torque parameters often fail to accurately reflect the actual output characteristics of the power source and transmission system, especially under complex scenarios such as extreme temperatures and different battery states of charge, where data consistency and accuracy are difficult to guarantee.

[0004] Furthermore, existing torque model calibration methods are mostly based on single operating conditions or ideal environmental conditions, lacking system testing and modeling of the coupled effects of multiple scenarios. This results in problems such as poor adaptability and large response deviation in torque control models in practical applications, which limits the further optimization of hybrid power system performance. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method and apparatus for torque testing and model calibration of hybrid power systems for multiple scenarios.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a torque testing and model calibration device for multi-scenario hybrid power systems, comprising: The test hybrid system includes an engine, a drive motor, and a hybrid coupling transmission; Powertrain test bench, including at least one load dynamometer; Multiple torque sensors are respectively installed at the flywheel output end of the engine, the output shaft end of the drive motor, and between the drive half-shaft of the test hybrid power system and the input shaft of the load dynamometer; A speed sensor is installed inside the load dynamometer and is used to measure the input shaft speed of the load dynamometer. The data acquisition system is communicatively connected to the torque sensor and the speed sensor, and is used to collect and store engine output torque, motor output torque, drive half-shaft torque and speed data in real time. A scenario simulation device for simulating at least one test scenario, including ambient temperature, altitude, and battery SOC.

[0007] Preferably, the torque sensor is connected to the flywheel of the engine, the output shaft of the drive motor, and the drive half-shaft via a flange; and / or, the output shaft of the test hybrid power system is installed at the same height as the input shaft of the load dynamometer.

[0008] Preferably, the data acquisition system supports wired and wireless communication methods to synchronously acquire signals from the torque sensor and the speed sensor, and communicate with the vehicle controller (VCU) to obtain a target torque request signal.

[0009] Preferably, the scene simulation device is capable of simulating the following combination of scenes: High temperature environment and low temperature environment; High-altitude and low-altitude environments; High SOC state and low SOC state; Among them, at least eight test scenarios are formed through permutation and combination.

[0010] Preferably, the powertrain test bench is a two-motor test bench or a four-motor test bench, and the number of load dynamometers matches the number of output terminals of the tested hybrid power system.

[0011] This invention also discloses a method for torque testing and model calibration of multi-scenario hybrid power systems, using the aforementioned apparatus, and comprising the following steps: Step 1: Perform stress analysis on the flywheel mechanical structure of the engine and the output shaft structure of the drive motor, and install torque sensors on the flywheel disk and the output shaft; Step 2: Install the test hybrid power system on the test bench base in the scenario simulation equipment, and connect the drive half shaft to the load dynamometer of the powertrain test bench through the connecting flange, and place a torque sensor at the connection point; Step 3: Connect the controller throttle signal line of the test hybrid system to the control unit of the powertrain bench; Step 4: Set up the test scenario, including the battery SOC, ambient temperature, and altitude of the hybrid power system being tested; Step 5: Set the test operating conditions, including the output speed of the power system and the throttle opening command; Step 6: Run the test under the set test scenario and test conditions, and collect the engine output torque, electric motor output torque and wheel end output torque through the torque sensor and the speed sensor; Step 7: Based on the collected torque data, calibrate the feedforward torque model and the feedback torque model.

[0012] Preferably, the test scenario set in the fourth step includes one of the following eight combinations: high altitude high SOC high temperature, high altitude high SOC low temperature, high altitude low SOC high temperature, high altitude low SOC low temperature, low altitude high SOC high temperature, low altitude high SOC low temperature, low altitude low SOC high temperature, low altitude low SOC high temperature, and low altitude low SOC low temperature.

[0013] Preferably, the specific steps for setting the test condition points in the fifth step include: For each working point in the test target working condition matrix, adjust the input shaft speed of the load dynamometer to match the target speed; The powertrain bench control unit sends a throttle opening command to adjust the throttle opening of the test hybrid system to the target throttle opening. After the test hybrid system enters a steady state and remains stable for a preset duration, torque and speed data for the preset test duration are collected by the torque sensor and the speed sensor. Preferably, the specific steps for calibrating the feedforward torque model and the feedback torque model in the seventh step include: Feedforward model calibration: A feedforward compensation model is established based on the collected actual torque data to pre-correct the demand torque command sent to the hybrid system control unit via the pedal signal; Feedback model calibration: Based on the comparison between the actual steady-state output torque value and the required torque, the torque error is adjusted using the calibrated feedback controller.

[0014] Preferably, the data acquisition system synchronously records the target torque signal requested by the vehicle controller (VCU), the throttle opening command issued by the powertrain bench control unit, and the actual torque and speed data collected by the torque sensor and speed sensor during the test, for comparison and calibration of the torque model.

[0015] The beneficial effects of this invention are as follows: Compared with the prior art, this invention has the following beneficial technical effects: 1. High-precision torque testing under multiple scenarios and operating conditions has been achieved. This invention integrates scenario simulation equipment to simulate various real-world operating scenarios in a laboratory environment, such as high and low temperatures (e.g., -20℃ to 60℃) and different battery SOCs (high / low charge). Combined with a powertrain bench and high-precision torque and speed sensors, it enables direct, real-time, and synchronous measurement of the output torque of the engine, motor, and wheel ends, effectively overcoming problems such as poor reproducibility of operating conditions, uncontrollable environmental conditions, and low data consistency in real-vehicle road testing.

[0016] 2. Improved the accuracy and reliability of torque data. By directly placing torque sensors at key power transmission locations such as the engine flywheel, motor output shaft, and drive half-shaft, the problems of signal delay, calibration error, and insufficient accuracy caused by relying on controller signals to indirectly obtain torque in traditional methods are avoided, thereby obtaining real and reliable system torque output data.

[0017] 3. Supports accurate calibration and system optimization of torque models. Based on the acquired measured torque data from multiple scenarios, combined with the VCU requested torque and bench control signals, this invention provides a complete method for calibrating feedforward and feedback torque models. This method can compensate for inherent system errors and perform closed-loop optimization of the torque control strategy, significantly improving the torque control accuracy and dynamic response performance of the hybrid power system.

[0018] 4. Possesses good versatility and scalability. The test system described in this invention has a flexible structure and can be adapted to various bench configurations such as two-motor or four-motor systems, making it suitable for testing hybrid power systems with different architectures. The data acquisition system supports multiple communication methods, including wired and wireless, and has strong compatibility and scalability, making it easy to promote and apply in different test platforms.

[0019] 5. Improve testing efficiency and engineering feasibility By conducting systematic testing under multiple scenarios and operating conditions in a bench environment, the development cycle is significantly shortened, and the cost and safety risks of real-vehicle testing are reduced, providing an efficient and reliable technical means for the development, verification, and performance improvement of hybrid power systems. Attached Figure Description

[0020] Figure 1 This is a block diagram of the overall structure of the present invention; Figure 1 In the middle, 1-load dynamometer; 2-torque sensor; 3-engine; 4-drive motor; 5-hybrid coupling gearbox; 6-hybrid system; 7-drive half-shaft; 8-signal acquisition system; 9-speed sensor; 10-scenario simulation equipment. Detailed Implementation

[0021] 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.

[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0023] In the description of this patent, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this patent according to the specific circumstances.

[0024] 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 one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0026] See Figure 1 The present invention provides a torque testing device for a hybrid power system for multiple scenarios, including a test hybrid power system 6, a powertrain test bench, a torque sensor 2, a speed sensor 3, a signal acquisition system 9, and a scenario simulation equipment 10; The test hybrid system 6 is equipped with a hybrid powertrain including an engine 3 and a drive motor 4; The powertrain test bench includes multiple load dynamometers 1 (i.e. load motors). The input shaft of the load dynamometer 1 is connected to the output drive half shaft of the test hybrid power system 6 via a torque sensor 2 (specifically, through a flange mechanical connection). Torque sensors 2 are respectively installed at the output end of the engine flywheel, the output end of the drive motor shaft, and the connection point between the drive half shaft of the hybrid power system and the output shaft of the load dynamometer. They are used to measure the engine output torque, drive motor output torque, and hybrid power system output half shaft torque in real time, and send the collected torque signals to the data acquisition system 8.

[0027] Each load dynamometer 1 is equipped with a speed sensor 3; The speed sensor 9 is connected to the input shaft of the load dynamometer 1 and is used to obtain the output speed of the drive half shaft of the test hybrid power system 6 connected to the input shaft by measuring the speed of the input shaft of the load dynamometer 1, and send the collected speed signal to the data acquisition system 8. The data acquisition system 8 is connected to the torque sensor 2 and the speed sensor 9 respectively, and is used to collect and store in real time the actual engine output torque, actual drive motor output torque, actual output end drive half shaft torque and actual output end drive half shaft speed of the test hybrid power system 6.

[0028] It should be noted that the engine, drive motor, and drive shaft are well-known and technologically mature components in existing hybrid vehicles, and will not be elaborated upon here.

[0029] In this invention, specifically, the bottom of each load dynamometer 1 included in the powertrain test bench is respectively mounted on an external horizontal mounting platform via vertically distributed dynamometer brackets.

[0030] In this invention, specifically, the hybrid power system includes an engine 3 disposed within the power system and a drive motor 4 disposed within the power system; In practice, the output drive half-shaft of the test hybrid power system 6 is connected to the torque sensor 2, which is connected to the input shaft of the load dynamometer 1 in the powertrain test bench, through a flange fixture (e.g., a flange).

[0031] It should be noted that the powertrain test bench is a mature existing technology test bench. Specifically, a powertrain test bench manufactured by AVL in Austria can be used to conduct working condition tests, which will not be elaborated here. The control system installed on the powertrain test bench is used to control the load dynamometer 1 to run at a preset speed, thereby controlling the vehicle speed. When the vehicle speed increases, the load dynamometer 1 uses AC frequency conversion to adjust the wheel end speed in real time.

[0032] It should be noted that a powertrain test bench is an indoor bench testing equipment used to test a vehicle's performance, fuel economy under various operating conditions, pure electric driving range, and pure electric energy consumption. The powertrain test bench simulates road resistance and uses a loading device to simulate different operating conditions of the vehicle.

[0033] In practice, the output drive half-shaft of the hybrid powertrain of the test hybrid system 6 and the input shaft of the load dynamometer 1 of the powertrain test bench are installed at the same height.

[0034] In this invention, specifically, a first connecting flange is provided between one end of the torque sensor 2 and the drive half-shaft of the test hybrid power system 6; A second connecting flange is provided between the other end of the torque sensor 2 and the input shaft of the load dynamometer 1.

[0035] In this invention, specifically, the throttle control harness of the test hybrid system 6 is connected to a controller installed on the powertrain bench, thereby enabling control of the throttle opening of the test hybrid system 6 via the powertrain bench.

[0036] Based on the torque testing device for multi-scenario hybrid power systems provided by the present invention, the present invention also provides a torque testing and model calibration method for multi-scenario hybrid power systems, specifically including the following steps: Step S1: Perform stress analysis on the mechanical structure of the engine flywheel and drive motor output shaft using the finite element analysis method to determine the positions of torque sensors on the engine flywheel disc and drive motor output shaft; Step S2: Set up the test system, rigidly fix the hybrid power system on the bench base inside the scenario simulation equipment, and connect its output drive half shaft to the torque sensor and load dynamometer in sequence through the connecting flange to ensure that each shaft system is aligned; Step S3: Connect the throttle signal line of the target hybrid system controller to the powertrain bench control unit, and send throttle commands to the target hybrid system through the bench control unit; Step S4: Set the test scenario for the target hybrid system, that is, set the battery SOC and operating ambient temperature of the target hybrid system; the temperature scenario is set as a high temperature scenario (ambient temperature 60℃±3℃) and a low temperature scenario (ambient temperature -20℃±3℃); the battery SOC is set as high SOC (SOC≥80%) and low SOC (SOC≤20%); and four scenarios are set in combination, namely high SOC & high temperature scenario, high SOC & low temperature scenario, low SOC & high temperature scenario, and low SOC & low temperature scenario. Step S5: Set the target operating condition matrix (Ni, βj) for the power characteristics of the target hybrid system. This test target operating condition matrix includes multiple different target speeds Ni and multiple different target throttle openings βj; there is a one-to-many mapping relationship between the target throttle opening βj and the target speed Ni. The test target operating condition matrix includes multiple operating condition points; Each operating point includes a target speed Ni and a target throttle opening βj corresponding to the target vehicle speed Ni; It should be noted that in a matrix, i and j usually represent the position index of the element. i: represents the row of the element, starting from 1 (or 0 in some scenarios). j: represents the column of the element, starting from 1 (or 0 in some scenarios).

[0037] In this invention, specifically, the test target operating condition matrix (Ni, βj) includes multiple target speeds Ni ranging from 100 r / min to the theoretical maximum speed, and the difference (i.e., the interval) between two target vehicle speeds Ni with similar values ​​is 100 r / min. In specific implementation, the test target working condition matrix (Ni, βj) can include a total of 10 target vehicle speeds, then i=10; In this invention, specifically, the test target working condition matrix (Ni, βj) includes multiple target throttle openings βj (i.e., target wheel speeds) with a value range of 0% to 100%, and the difference (i.e., interval) between two target throttle openings βj with similar values ​​is 10%. In specific implementation, the test target operating condition matrix (Ni, βj) can include a total of 10 target throttle openings, then j=10, thus obtaining the test operating condition matrix (Ni, βj) of the test hybrid system 6 for speed and throttle opening.

[0038] In this invention, specifically, before setting the test target operating condition matrix for the test hybrid power system 6, it is necessary to refer to... Figure 1 As shown, the powertrain test bench has been set up.

[0039] Step S6: Start the test system. The target hybrid power system is controlled by the test bench controller on the powertrain test bench to run under the operating conditions set in step S5 and the scenarios set in step S4 respectively. In step S5, the specific implementation includes the following steps: Step S51: For any working point in the test target working condition matrix, adjust the input shaft speed of the load dynamometer 1 to match the target speed Ni of that working condition, so that the actual speed N of the test hybrid power system 6 reaches the target speed Ni specified in that working condition and maintains stable driving at the target speed Ni. Step S52: For any working point in the test target working condition matrix, the throttle opening of the test hybrid system 6 is adjusted by the powertrain bench controller so that its throttle opening β reaches βi in the target working condition and is kept stable at the target βi.

[0040] Step S6: The actual output torque of the engine and drive motor is directly measured in real time through the first torque sensor and the second torque sensor; the input shaft torque of the load dynamometer is directly measured in real time through the half-shaft torque sensor, that is, the real-time data of the output half-shaft torque of the hybrid vehicle system. Step S7: The data acquisition system synchronously records the measured data of all sensors and the internal signal data of the VCU, and analyzes and processes the data to obtain accurate torque parameters of the power system.

[0041] Step S8: Based on the actual steady-state output torque values ​​of the engine and motor under different scenarios and loads, as well as the corresponding pedal opening signal values ​​issued by the bench control unit, the torque model can be calibrated, as follows; Step S8 1. Feedforward model calibration: Based on the torque parameters obtained in S7, a feedforward compensation model is established; this model is used to pre-correct the demand torque command executed after being sent to the hybrid power system control unit through the pedal signal, so as to offset the inherent error of the system.

[0042] Step S8 2, Feedback Model Calibration: Calibrate the parameters of the closed-loop feedback control unit based on the actual torque calculation; based on the actual steady-state output torque value obtained from tests under different scenarios and loads, compare it with the required torque using a large amount of data, and adjust the torque error using the calibrated feedback controller.

[0043] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A torque testing and model calibration device for multi-scenario hybrid power systems, characterized in that, include: The test hybrid system (6) includes an engine (3), a drive motor (4) and a hybrid coupling transmission (5). A powertrain test bench, including at least one load dynamometer (1). Multiple torque sensors (2) are respectively located at the flywheel output end of the engine (3), the output shaft end of the drive motor (4), and between the drive half shaft (7) of the test hybrid power system (6) and the input shaft of the load dynamometer (1); A speed sensor (9) is installed inside the load dynamometer (1) and is used to measure the input shaft speed of the load dynamometer (1); The data acquisition system (8) is communicatively connected to the torque sensor (2) and the speed sensor (9) and is used to collect and store engine output torque, motor output torque, drive half shaft torque and speed data in real time; A scenario simulation device (10) is used to simulate at least one test scenario among ambient temperature, altitude and battery SOC.

2. The apparatus as claimed in claim 1, characterized in that, The torque sensor (2) is connected to the flywheel of the engine (3), the output shaft of the drive motor (4) and the drive half shaft (7) respectively via a flange; and / or, the output shaft of the test hybrid power system (6) is installed at the same height as the input shaft of the load dynamometer (1).

3. The apparatus as described in claim 1, characterized in that, The data acquisition system (8) supports wired and wireless communication methods, and is used to synchronously acquire the signals of the torque sensor (2) and the speed sensor (9), and communicate with the vehicle controller (VCU) to obtain the target torque request signal.

4. The apparatus as claimed in claim 1, characterized in that, The scene simulation device (10) is capable of simulating the following scene combinations: High temperature environment: 60℃±3℃ and low temperature environment: -20℃±3℃; High-altitude and low-altitude environments; High SOC state: SOC ≥ 80% and low SOC state: SOC ≤ 20%; Among them, at least eight test scenarios are formed through permutation and combination.

5. The apparatus as claimed in claim 1, characterized in that, The powertrain test bench is a two-motor test bench or a four-motor test bench, and the number of load dynamometers (1) matches the number of output terminals of the test hybrid power system (6).

6. A method for torque testing and model calibration of a multi-scenario hybrid power system, employing the apparatus as described in any one of claims 1-5, characterized in that, Includes the following steps: Step S1: Perform stress analysis on the flywheel mechanical structure of the engine (3) and the output shaft structure of the drive motor (4), and install torque sensors (2) on the flywheel disk and the output shaft. Step S2: Install the test hybrid power system (6) on the bench base in the scenario simulation equipment (10), and connect the drive half shaft (7) to the load dynamometer (1) of the powertrain bench through the connecting flange, and arrange the torque sensor (2) at the connection point. Step S3: Connect the controller throttle signal line of the test hybrid system (6) to the control unit of the powertrain bench; Step S4: Set the test scenario, including the battery SOC, ambient temperature and altitude of the test hybrid power system (6); Step S5: Set the test operating point, including the power system output speed N(i,j) and throttle opening command β(i,j); Step S6: Run the test under the set test scenario and test condition points, and collect the engine output torque, electric motor output torque and wheel end output torque through the torque sensor (2) and the speed sensor (9); Step S7: Based on the collected torque data, calibrate the feedforward torque model and the feedback torque model.

7. The method as described in claim 6, characterized in that, The test scenario set in step S4 includes one of the following eight combinations: High altitude, high SOC, and high temperature environments; High altitude, high SOC, low temperature environments; High altitude, low SOC, high temperature scenarios; High-altitude, low-SOC, and low-temperature environments; Low altitude, high SOC, high temperature scenarios; Low altitude, high SOC, low temperature scenarios; Low altitude, low SOC, high temperature scenarios; Low altitude, low SOC, and low temperature scenarios.

8. The method as described in claim 6, characterized in that, The specific steps for setting the test condition points in step S5 include: Step S51: For each working point in the test target working condition matrix, adjust the input shaft speed of the load dynamometer (1) to match the target speed Ni; Step S52: Send a throttle opening command through the powertrain bench control unit to adjust the throttle opening of the test hybrid system (6) to the target throttle opening βi; Step S53: After the test hybrid power system (6) enters a steady state and remains stable for a preset duration, torque and speed data for a preset test duration T are collected by the torque sensor (2) and the speed sensor (9).

9. The method as described in claim 6, characterized in that, The specific steps for calibrating the feedforward torque model and the feedback torque model in step S7 include: Feedforward model calibration: A feedforward compensation model is established based on the collected actual torque data to pre-correct the demand torque command sent to the hybrid system control unit via the pedal signal; Feedback model calibration: Based on the comparison between the actual steady-state output torque value and the required torque, the torque error is adjusted using the calibrated feedback controller.

10. The method as described in claim 6, characterized in that, The data acquisition system (8) synchronously records the target torque signal requested by the vehicle controller (VCU), the throttle opening command issued by the powertrain bench control unit, and the actual torque and speed data collected by the torque sensor (2) and the speed sensor (9) during the test, for comparison and calibration of the torque model.

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