Test methods, devices, electronic equipment, and vehicles for electric drive systems.

Abstract

This application provides a method, apparatus, electronic device, and vehicle for testing an electric drive system. The method involves controlling the motor torque of the electric drive system from a target negative torque to a target positive torque according to a first torque change rate, and collecting a first vibration signal from the electric drive system; controlling the motor torque of the electric drive system from a target positive torque to a target negative torque according to a second torque change rate, and collecting a second vibration signal from the electric drive system; adjusting the first torque change rate based on the first vibration signal, and adjusting the second torque change rate based on the second vibration signal, to adjust the impact intensity of the electric drive system when the motor torque crosses zero. This application, by testing the electric drive system, identifies the impact intensity of the electric drive system under zero-crossing conditions in advance, optimizes the impact intensity of the electric drive system when the motor torque crosses zero, and controls it within an acceptable range for vehicle occupants, thereby improving the driving comfort of the vehicle under acceleration and deceleration conditions.

Description

Technical Field

[0001] This application relates to the field of testing technology, and in particular to a method, apparatus, electronic device, and vehicle for testing an electric drive system. Background Technology

[0002] Compared to traditional gasoline vehicles, new energy vehicles use electric motors instead of engines as their power source, enabling vehicle propulsion and energy recovery. The electric drive transmission system of new energy vehicles typically uses gears and splines to transmit power, and there is inherent backlash between these gears and splines. The entire electric drive assembly, from the motor to the gear transmission system, and then through the half-shafts to the wheels, involves multiple mechanical transmission gaps. During vehicle acceleration or deceleration, the motor torque of the electric drive system undergoes a transition from positive to negative or vice versa. When the motor torque crosses zero, the driving gear in the transmission system needs to overcome the transmission gaps to reach the driven gear to achieve the functional switch between vehicle propulsion and energy recovery. This process can cause knocking between the driving and driven gears. The faster the rate of change of the motor torque across zero, the stronger the knocking intensity of the transmission system, which can negatively impact the ride comfort of passengers.

[0003] Currently, there is no technical solution that can effectively test, identify, and optimize the impact intensity of electric drive systems when the motor torque crosses zero. Summary of the Invention

[0004] This application provides a method, apparatus, electronic device, and vehicle for testing an electric drive system, aiming to address the problem in the related art of lacking a technical solution that can effectively test, identify, and optimize the impact intensity of an electric drive system under the condition of zero torque crossing.

[0005] To address the aforementioned problems, this application discloses a testing method for a vehicle's electric drive system. The electric drive system includes a motor, which has a corresponding motor torque. The method includes: Acquire test parameters, including target negative torque, target positive torque, first torque change rate, and second torque change rate; According to the first torque change rate, the motor torque of the electric drive system is controlled to change from the target negative torque to the target positive torque, and a first vibration signal of the electric drive system is collected. The first vibration signal reflects the impact intensity of the electric drive system when the motor torque rises from zero. According to the second torque change rate, the motor torque of the electric drive system is controlled to change from the target positive torque to the target negative torque, and a second vibration signal of the electric drive system is collected. The second vibration signal reflects the impact intensity of the electric drive system when the motor torque drops to zero. The first torque change rate is adjusted according to the first vibration signal, and the second torque change rate is adjusted according to the second vibration signal, so as to adjust the knocking intensity of the electric drive system when the motor torque crosses zero.

[0006] This application embodiment simulates the operating state of the electric drive system under the conditions of motor torque rising and falling below zero, respectively, according to a first torque change rate and a second torque change rate. A first vibration signal and a second vibration signal are collected accordingly. The first vibration signal reflects the impact intensity of the electric drive system during the rising of motor torque above zero, and the second vibration signal reflects the impact intensity during the falling of motor torque below zero. By testing the electric drive system, the impact intensity under the condition of motor torque falling below zero can be identified in advance, thereby effectively shortening the development cycle of the electric drive system and reducing the cost of changes during development. This application embodiment adjusts the first and second torque change rates based on the test results to optimize the impact intensity of the electric drive system when the motor torque falls below zero, controlling it within an acceptable range for vehicle occupants to avoid discomfort and thus improve driving comfort during acceleration and deceleration.

[0007] Optionally, adjusting the first torque change rate based on the first vibration signal and adjusting the second torque change rate based on the second vibration signal includes: The first vibration peak value and the first effective vibration value when the electric drive system is struck are determined based on the first vibration signal. The ratio of the first vibration peak value to the first vibration effective value is determined to obtain the zero-crossing rise peak factor of the motor torque, which represents the impact intensity of the electric drive system when the motor torque rises at zero. The second vibration peak value and the second effective vibration value when the electric drive system is struck are determined based on the second vibration signal. The ratio of the second vibration peak value to the second vibration effective value is determined to obtain the zero-crossing drop peak factor of the motor torque, which represents the knocking intensity of the electric drive system when the motor torque drops to zero. The first torque change rate is adjusted according to the zero-crossing rising peak factor, and the second torque change rate is adjusted according to the zero-crossing falling peak factor.

[0008] According to the embodiments of this application, the zero-crossing rising peak factor and the zero-crossing falling peak factor of the motor torque are determined based on the ratio of the vibration peak value to the vibration effective value in the vibration signal. The zero-crossing rising peak factor and the zero-crossing falling peak factor determined by the ratio of the vibration peak value to the vibration effective value can more effectively characterize the impact intensity of the electric drive system when the motor torque crosses zero, thereby improving the accuracy of subsequent adjustments to the first torque change rate and the second torque change rate.

[0009] Optionally, the method includes: According to the first torque change rate, the motor torque of the electric drive system is controlled to change from the target negative torque to the target positive torque, and the first vibration signal of the electric drive system is collected to determine the corresponding zero-crossing rise peak factor based on the first vibration signal. The zero-crossing rise peak factor of the motor torque is determined based on the average value of the zero-crossing rise peak factor. According to the second torque change rate, the motor torque of the electric drive system is controlled to change from the target positive torque to the target negative torque, and the second vibration signal of the electric drive system is collected to determine the corresponding zero-crossing descent peak factor based on the second vibration signal; The zero-crossing descent peak factor of the motor torque is determined based on the average value of the zero-crossing descent peak factor.

[0010] This application embodiment performs multiple zero-crossing tests on the electric drive system. The zero-crossing rising peak factor of the motor torque is determined by the average value of the zero-crossing rising peak factor obtained from multiple tests, and the zero-crossing falling peak factor of the motor torque is determined by the average value of the zero-crossing falling peak factor obtained from multiple tests. This avoids the occasional influence of a single test and improves the accuracy of the striking intensity when the motor torque crosses zero.

[0011] Optionally, adjusting the first torque change rate according to the zero-crossing rising peak factor and adjusting the second torque change rate according to the zero-crossing falling peak factor includes: If the zero-crossing rise peak factor is greater than the first factor threshold, then the first torque change rate is adjusted according to the ratio of the zero-crossing rise peak factor to the first factor threshold; and / or, If the zero-crossing descent peak factor is greater than the second factor threshold, the second torque change rate is adjusted according to the ratio of the zero-crossing descent peak factor to the second factor threshold.

[0012] This application embodiment identifies and judges the impact intensity of the electric drive system under the condition of zero-crossing torque by using the zero-crossing rising peak factor and the zero-crossing falling peak factor. When the zero-crossing rising peak factor is greater than the first factor threshold and / or the zero-crossing falling peak factor is greater than the second factor threshold, the corresponding torque change rate needs to be adjusted, thereby optimizing the impact intensity of the electric drive system under the condition of zero-crossing torque, so that the impact intensity is controlled within the acceptable range for the occupants, avoiding discomfort, and thus improving the driving comfort of the vehicle under acceleration and deceleration conditions.

[0013] Optionally, the method further includes: If the zero-crossing rising peak factor is less than or equal to the first factor threshold, and the zero-crossing falling peak factor is less than or equal to the second factor threshold, then the first torque change rate and the second torque change rate are output.

[0014] In this embodiment of the application, when the zero-crossing rising peak factor is less than or equal to the first factor threshold and the zero-crossing falling peak factor is less than or equal to the second factor threshold, it can be considered that the impact intensity of the electric drive system under the zero-crossing motor torque condition is within the acceptable range for the occupants. The zero-crossing motor torque condition of the vehicle's electric drive system can be controlled according to the current first torque change rate and second torque change rate, thereby improving the driving comfort of the vehicle under acceleration and deceleration conditions.

[0015] Optionally, the electric drive system includes a suspension bracket, the electric drive system is located on a preset electric drive test bench, and the electric drive test bench is used to control the change of the motor torque; The motor includes an input gear; A vibration sensor is arranged at the target suspension bracket mounting point closest to the input gear transmission position of the motor in the electric drive system. The vibration sensor is used to collect the first vibration signal and the second vibration signal.

[0016] This application embodiment utilizes an electric drive test bench to simulate the impact phenomenon of a vehicle's electric drive system. It eliminates the need to install vibration sensors on the new energy vehicle for testing and judgment. Furthermore, by placing a vibration sensor at the target suspension bracket mounting point closest to the input gear transmission position of the motor, vibration signals that better reflect the impact intensity of the electric drive system can be collected. This effectively simulates the impact phenomenon of the vehicle's electric drive system and collects test data for subsequent identification and judgment of the impact intensity of the electric drive system. This shortens the development cycle of the vehicle and its electric drive system, and reduces the testing and optimization costs of the electric drive system.

[0017] Optionally, the electric drive test bench includes a left half-shaft and a right half-shaft. After obtaining the target negative torque, the target positive torque, the first torque change rate, and the second torque change rate, the method includes: Obtain the test speed of the vehicle; The test speeds of the left and right half-shafts of the electric drive test bench are determined based on the test vehicle speed. The electric drive system is tested when the left and right half-shafts of the electric drive test bench rotate at the test speed.

[0018] This application embodiment simulates the impact phenomenon of the electric drive system of a vehicle at the test speed using an electric drive test bench. This eliminates the need to install vibration sensors on the new energy vehicle for testing and judgment, shortens the development cycle of the vehicle and the vehicle's electric drive system, and reduces the testing and optimization costs of the electric drive system.

[0019] This application also discloses a vehicle electric drive system testing device, the electric drive system including a motor, the motor having a corresponding motor torque, and the device comprising: The data acquisition module is used to acquire the target negative torque, the target positive torque, the first torque change rate, and the second torque change rate; The first test module is used to control the motor torque of the electric drive system to change from the target negative torque to the target positive torque according to the first torque change rate, and to collect the first vibration signal of the electric drive system, wherein the first vibration signal reflects the impact intensity of the electric drive system when the motor torque rises from zero. The second test module is used to control the motor torque of the electric drive system to change from the target positive torque to the target negative torque according to the second torque change rate, and to collect the second vibration signal of the electric drive system, the second vibration signal reflecting the impact intensity of the electric drive system when the motor torque drops to zero; The data adjustment module is used to adjust the first torque change rate and the second torque change rate according to the first vibration signal and the second vibration signal, respectively, so as to adjust the impact intensity of the electric drive system when the motor torque crosses zero.

[0020] This application also discloses an electronic device, including a processor and a memory, wherein the memory is used to store computer programs; the processor is used to execute the programs stored in the memory to implement the electric drive system testing method for a vehicle as described in one or more of the embodiments of this application.

[0021] This application also discloses a vehicle that includes electronic devices as described in the embodiments of this application. Attached Figure Description

[0022] Figure 1A This is a schematic diagram of the energy recovery of the electric drive system in a vehicle electric drive system testing method provided in an embodiment of this application; Figure 1BThis is a schematic diagram of an electric drive system driving a vehicle, provided in an embodiment of the vehicle electric drive system testing method of this application; Figure 2A This is a schematic diagram of the forward impact of the electric drive system in a vehicle electric drive system testing method provided in an embodiment of this application; Figure 2B This is a schematic diagram of the tooth removal of the electric drive system in a vehicle electric drive system testing method provided in an embodiment of this application; Figure 2C This is a schematic diagram of the reverse impact of the electric drive system in a vehicle electric drive system testing method provided in an embodiment of this application; Figure 3 This is a flowchart of a vehicle electric drive system testing method provided in one embodiment of this application; Figure 4A This is a schematic diagram of the motor torque zero-crossing vibration signal processing in a vehicle electric drive system testing method provided in an embodiment of this application. Figure 4B This is a schematic diagram of the vibration signal processing for the zero-crossing vibration of the motor torque in a vehicle electric drive system testing method provided in an embodiment of this application; Figure 5 This is a test flowchart of a vehicle electric drive system test method provided in one embodiment of this application; Figure 6 This is a structural diagram of the vehicle electric drive system testing device provided in the embodiments of this application; Figure 7 This is a structural diagram of the electronic device provided in the embodiments of this application. Detailed Implementation

[0023] To make the technical problems, technical solutions, and beneficial effects solved by this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0024] With social progress and technological development, environmental and energy issues are becoming increasingly prominent, making the development and popularization of new energy vehicles a mainstream trend. In recent years, new energy vehicles have developed rapidly, with a large number appearing on the market. As new energy vehicles rapidly become more widespread, people's requirements for them are becoming increasingly stringent. Comfort, safety, and durability have become important evaluation indicators for consumers when purchasing vehicles. Compared to traditional fuel vehicles, the power source of a new energy vehicle has changed from an engine to an electric motor. Electric motors offer faster torque response than engines, providing instantaneous response, and they can also achieve energy recovery functions that fuel vehicles lack, such as… Figures 1A-1B As shown.

[0025] Reference Figure 1AThis is a schematic diagram of the energy recovery of the electric drive system in a vehicle electric drive system testing method provided in an embodiment of this application.

[0026] like Figure 1A As shown, when the vehicle is decelerating, the kinetic energy of the entire vehicle is transferred from the wheels to the electric drive system (i.e., the electric drive assembly) through the half-shaft. The electric drive system motor has a negative torque, which converts the kinetic energy of the entire vehicle into electrical energy and stores it in the battery, thereby achieving deceleration of the entire vehicle while increasing the driving range of the electric vehicle.

[0027] Reference Figure 1B This is a schematic diagram of an electric drive system driving a vehicle, provided in an embodiment of the present application, for testing the electric drive system of a vehicle.

[0028] like Figure 1B As shown, when the vehicle is accelerating, the battery outputs electrical energy to the electric drive system, the motor torque is positive, and the wheels are driven through the half-shaft to achieve vehicle acceleration.

[0029] In vehicle electric drive systems, transmission typically occurs via gears and splines. Backlash exists between gear and spline pairs, such as... Figures 2A-2C As shown, the electric drive assembly, from the motor to the gear transmission system, and then through the half-shafts to the wheels, involves multiple mechanical transmission backlashes. These backlashes accumulate, and the powertrain transmission backlashes cannot be completely eliminated; they can only be controlled within a certain range. When the vehicle is accelerating or decelerating, the electric drive system's motor torque changes from positive to negative torque, and vice versa. During this process, when the motor torque passes through zero torque, the driving gear in the transmission system needs to overcome the transmission backlash to reach the driven gear to switch between vehicle driving or energy recovery functions. This results in a knocking phenomenon between the driving and driven gears in the transmission system. The faster the rate of change of the motor torque at zero, the greater the knocking in the transmission system. Therefore, it is necessary to adjust the zero-crossing slope of the motor torque to reduce gear knocking.

[0030] exist Figures 2A-2C In the diagram, X1(t) represents the displacement of the driving gear, X2(t) represents the displacement of the driven gear, b represents half the gear clearance, and m... e F is the equivalent mass of the gear. r F D r is the force acting on the gear. b1 ,θ1,r b2 θ2 are the physical parameters of the gear.

[0031] Reference Figure 2A This is a schematic diagram of the positive impact of the electric drive system in the electric drive system test method of a vehicle provided in an embodiment of this application, that is, when X1(t)-X2(t)>2b, the gear is subjected to a positive impact.

[0032] Reference Figure 2B This is a schematic diagram of the gear de-gearing state of the electric drive system of the vehicle electric drive system test method provided in an embodiment of this application, that is, when 2b>X1(t)-X2(t)>-2b gear de-gearing state.

[0033] Reference Figure 2C This is a schematic diagram of the reverse impact of the electric drive system in a vehicle electric drive system testing method provided in an embodiment of this application, that is, when X1(t)-X2(t)<-2b, the gear experiences a reverse impact.

[0034] exist Figures 2A to 2C In the electric drive system, the motor torque changes from positive to negative. Initially, the gears are in positive engagement. As the torque reaches zero, the gears begin to disengage. When the torque reaches negative, the displacement of the primary and driven gears reaches 2b, and the gears produce a reverse knocking motion. In the electric drive system, the motor torque changes from negative to positive. Initially, the gears are in reverse engagement. As the torque reaches zero, the gears begin to disengage. When the torque reaches positive, the displacement of the primary and driven gears reaches 2b, and the gears produce a positive knocking motion.

[0035] However, the relevant technologies only involve technical solutions such as the identification of knocking under no-load conditions of electric drive systems, the location diagnosis and identification of vehicle impact noise, and the control method for preventing transmission system gap impact when the motor torque of new energy vehicles crosses zero. None of them consider the effective testing, identification and optimization of the knocking intensity of electric drive systems under the condition of motor torque crossing zero.

[0036] Therefore, this application provides a method for testing an electric drive system of a vehicle. The electric drive system includes a motor with a corresponding motor torque. The method includes: acquiring test parameters, including a target negative torque, a target positive torque, a first torque change rate, and a second torque change rate; controlling the motor torque of the electric drive system to change from the target negative torque to the target positive torque according to the first torque change rate, and collecting a first vibration signal of the electric drive system, the first vibration signal reflecting the impact intensity of the electric drive system when the motor torque rises above zero; controlling the motor torque of the electric drive system to change from the target positive torque to the target negative torque according to the second torque change rate, and collecting a second vibration signal of the electric drive system, the second vibration signal reflecting the impact intensity of the electric drive system when the motor torque falls below zero; adjusting the first torque change rate according to the first vibration signal, and adjusting the second torque change rate according to the second vibration signal, to adjust the impact intensity of the electric drive system when the motor torque falls below zero.

[0037] This application embodiment simulates the operating state of the electric drive system under the conditions of motor torque rising and falling below zero, respectively, according to a first torque change rate and a second torque change rate. A first vibration signal and a second vibration signal are collected accordingly. The first vibration signal reflects the impact intensity of the electric drive system during the rising of motor torque above zero, and the second vibration signal reflects the impact intensity during the falling of motor torque below zero. By testing the electric drive system, the impact intensity under the condition of motor torque falling below zero can be identified in advance, thereby effectively shortening the development cycle of the electric drive system and reducing the cost of changes during development. This application embodiment adjusts the first and second torque change rates based on the test results to optimize the impact intensity of the electric drive system when the motor torque falls below zero, controlling it within an acceptable range for vehicle occupants to avoid discomfort and thus improve driving comfort during acceleration and deceleration.

[0038] Example 1 This application provides a method for testing a vehicle's electric drive system. Please refer to [the relevant documentation]. Figure 3 This includes the following steps: S310: Obtain test parameters, including target negative torque, target positive torque, first torque change rate, and second torque change rate.

[0039] The electric drive system in this application embodiment is an electric drive system on a vehicle, wherein the electric drive system includes a motor, and the motor has a corresponding motor torque.

[0040] In step S310, the obtained test parameters include the target negative torque -T (Nm), the target positive torque T (Nm), the first torque change rate A1 (Nm / s), and the second torque change rate A2 (Nm / s).

[0041] In one example, T can be selected within the range of 5-20 Nm, the initial first torque change rate can be 40 Nm / s, and the initial second torque change rate can be 10 Nm / s. The specific values ​​mentioned above are merely examples, and this application does not limit the specific values ​​of the test parameters.

[0042] S320: According to the first torque change rate, control the motor torque of the electric drive system to change from the target negative torque to the target positive torque, and collect the first vibration signal of the electric drive system, the first vibration signal reflecting the impact intensity of the electric drive system when the motor torque rises above zero.

[0043] In step S320, the motor torque of the electric drive system is controlled to change from the target negative torque to the target positive torque according to the first torque change rate, simulating the vehicle's coasting to low speed and then acceleration. During this process, the first vibration signal of the electric drive system is collected by the vibration sensor. The first vibration signal can reflect the impact intensity of the electric drive system when the motor torque rises from zero.

[0044] In one example, because the faster the motor torque changes when it crosses zero torque, the greater the impact vibration, the motor's zero-torque rate is generally controlled within 80 Nm / s. Therefore, the initial first torque change rate is set to 40 Nm / s. The target negative torque is -10 Nm, and the target positive torque is 10 Nm. The motor torque changes from the target negative torque to the target positive torque at a first torque change rate of 40 Nm / s, taking 0.5 seconds. During this process, the first vibration signal of the electric drive system is collected.

[0045] S330: According to the second torque change rate, control the motor torque of the electric drive system to change from the target positive torque to the target negative torque, and collect the second vibration signal of the electric drive system, the second vibration signal reflecting the impact intensity of the electric drive system when the motor torque drops to zero.

[0046] In step S330, the motor torque of the electric drive system is controlled to change from the target positive torque to the target negative torque according to the second torque change rate, simulating the acceleration and coasting recovery of the vehicle. During this process, the second vibration signal of the electric drive system is collected by the vibration sensor. The second vibration signal can reflect the impact intensity of the electric drive system when the motor torque drops to zero.

[0047] In one example, because the electric drive system has internal resistance and negative torque, the vibration from positive torque to negative torque is greater than the vibration from negative torque to positive torque. Therefore, the second rate of change from positive torque to negative torque usually needs to be set smaller than the first rate of change. Simultaneously, when the driver releases the accelerator, the rate of decrease in motor torque should not be too rapid to avoid noticeable jerking and dragging sensations in the vehicle, which could cause motion sickness and discomfort for passengers. Therefore, the initial second torque change rate is set to 10 Nm / s. The target negative torque is -10 Nm, and the target positive torque is 10 Nm. The motor torque changes from the target positive torque to the target negative torque at a second torque change rate of 10 Nm / s, taking 2 seconds. During this process, the second vibration signal of the electric drive system is collected.

[0048] S340: Adjust the first torque change rate according to the first vibration signal, and adjust the second torque change rate according to the second vibration signal to adjust the impact intensity of the electric drive system when the motor torque crosses zero.

[0049] In step S340, the impact intensity of the electric drive system motor torque rising when it crosses zero can be identified and determined by analyzing the first vibration signal collected from the vibration sensor data, and the impact intensity of the electric drive system motor torque falling when it crosses zero can be identified and determined by analyzing the second vibration signal collected from the vibration sensor data. The first torque change rate is adjusted based on the first vibration signal, and the second torque change rate is adjusted based on the second vibration signal, thereby optimizing the impact intensity of the electric drive system when the motor torque crosses zero by adjusting the zero-crossing slope, so that the impact intensity of the electric drive system when the motor torque crosses zero is within an acceptable range for the occupants of the vehicle.

[0050] In one embodiment, the impact intensity of the electric drive system can also be reduced by decreasing the transmission clearance of the electric drive system.

[0051] This application embodiment simulates the operating state of the electric drive system under the conditions of motor torque rising and falling below zero, respectively, according to a first torque change rate and a second torque change rate. A first vibration signal and a second vibration signal are collected accordingly. The first vibration signal reflects the impact intensity of the electric drive system during the rising of motor torque above zero, and the second vibration signal reflects the impact intensity during the falling of motor torque below zero. By testing the electric drive system, the impact intensity under the condition of motor torque falling below zero can be identified in advance, thereby effectively shortening the development cycle of the electric drive system and reducing the cost of changes during development. This application embodiment adjusts the first and second torque change rates based on the test results to optimize the impact intensity of the electric drive system when the motor torque falls below zero, controlling it within an acceptable range for vehicle occupants to avoid discomfort and thus improve driving comfort during acceleration and deceleration.

[0052] Optionally, the electric drive system includes a suspension bracket, the electric drive system is located on a preset electric drive test bench, and the electric drive test bench is used to control the change of the motor torque; The motor includes an input gear; A vibration sensor is arranged at the target suspension bracket mounting point closest to the input gear transmission position of the motor in the electric drive system. The vibration sensor is used to collect the first vibration signal and the second vibration signal.

[0053] In the design verification stage of the electric drive system, this application embodiment can identify and optimize the impact intensity of the electric drive system when the motor torque crosses zero by conducting tests on an electric drive test bench.

[0054] Specifically, before the test begins, the electric drive system is installed on a preset electric drive test bench. The electric drive test bench is used to control the change of the machine torque. The electric drive system needs to be connected to high and low voltage power supplies, a cooling system, and the left and right half-shafts. The left and right half-shafts are connected to the dynamometer to ensure that the electric drive system can work normally.

[0055] The motor includes an input gear. Since the first transmission gap transmitted by the motor torque when it changes signifies a change in torque is the transmission gap position of the input gear, and since the vibration of the electric drive system is transmitted to the vehicle subframe and body through the suspension bracket, this embodiment of the application determines the impact intensity of the electric drive system by collecting the vibration signal from the target suspension bracket mounting point closest to the transmission position of the motor's input gear. A vibration sensor is arranged at the target suspension bracket mounting point closest to the transmission position of the motor's input gear in the electric drive system. The vibration sensor is used to collect the first vibration signal and the second vibration signal.

[0056] This application embodiment utilizes an electric drive test bench to simulate the impact phenomenon of a vehicle's electric drive system. It eliminates the need to install vibration sensors on the new energy vehicle for testing and judgment. Furthermore, by placing a vibration sensor at the target suspension bracket mounting point closest to the input gear transmission position of the motor, vibration signals that better reflect the impact intensity of the electric drive system can be collected. This effectively simulates the impact phenomenon of the vehicle's electric drive system and collects test data for subsequent identification and judgment of the impact intensity of the electric drive system. This shortens the development cycle of the vehicle and its electric drive system, and reduces the testing and optimization costs of the electric drive system.

[0057] Optionally, the electric drive test bench includes a left half-shaft and a right half-shaft, and after step S310, the method includes: Obtain the test speed of the vehicle; The test speeds of the left and right half-shafts of the electric drive test bench are determined based on the test vehicle speed. The electric drive system is tested when the left and right half-shafts of the electric drive test bench rotate at the test speed.

[0058] In this embodiment of the application, after the electric drive system is installed on the electric drive test bench and vibration sensors are arranged, before starting the subsequent test steps, the left and right half-shafts of the electric drive test bench are controlled to rotate at the test speed to simulate the knocking phenomenon of the vehicle at the test speed.

[0059] Specifically, on the electric drive test bench, the speed range in which the electric drive system of the vehicle is most affected by the impact is identified, and the test speed is selected from the speed range.

[0060] In one embodiment, the vehicle speed range can be determined empirically. Because the background noise inside the vehicle is low at low speeds, the knocking sound from the electric drive system is more noticeable; conversely, the higher the vehicle speed, the higher the electric drive speed, and the faster the zero torque passes through the transmission gap, making knocking less likely. Typically, when the vehicle speed is below 8 km / h, it is in crawl mode, and the motor maintains positive torque to drive the vehicle in a crawling motion. Therefore, a speed range of 8–20 km / h can be used for testing, as the knocking sound from the electric drive system has the greatest impact on the occupants within this speed range.

[0061] After obtaining the test speed of the vehicle in this embodiment, the test speed corresponding to the left and right half-shafts of the electric drive test bench is determined according to the test speed. The left and right half-shafts are then rotated according to the test speed. While the left and right half-shafts are rotating according to the test speed, the electric drive system is tested to simulate the operating state of the electric drive system under the conditions of zero torque rise and zero torque fall, according to the first torque change rate and the second torque change rate.

[0062] In one example, the test vehicle speed can be set to 10 km / h, corresponding to a test rotation speed of 75 r / min. The left and right half-shafts of the electric drive test bench are controlled to rotate at 75 r / min for subsequent testing procedures.

[0063] This application embodiment simulates the impact phenomenon of the electric drive system of a vehicle at the test speed using an electric drive test bench. This eliminates the need to install vibration sensors on the new energy vehicle for testing and judgment, shortens the development cycle of the vehicle and the vehicle's electric drive system, and reduces the testing and optimization costs of the electric drive system.

[0064] Optionally, adjusting the first torque change rate based on the first vibration signal and adjusting the second torque change rate based on the second vibration signal includes: The first vibration peak value and the first effective vibration value when the electric drive system is struck are determined based on the first vibration signal. The ratio of the first vibration peak value to the first vibration effective value is determined to obtain the zero-crossing rise peak factor of the motor torque, which represents the impact intensity of the electric drive system when the motor torque rises at zero. The second vibration peak value and the second effective vibration value when the electric drive system is struck are determined based on the second vibration signal. The ratio of the second vibration peak value to the second vibration effective value is determined to obtain the zero-crossing drop peak factor of the motor torque, which represents the knocking intensity of the electric drive system when the motor torque drops to zero. The first torque change rate is adjusted according to the zero-crossing rising peak factor, and the second torque change rate is adjusted according to the zero-crossing falling peak factor.

[0065] In this embodiment of the application, after collecting the first vibration signal and the second vibration signal, the impact intensity of the electric drive system when the motor torque crosses zero is identified and judged based on the collected first vibration signal and the second vibration signal. That is, the zero-crossing rising peak factor and the zero-crossing falling peak factor of the electric drive system are calculated respectively through the first vibration signal and the second vibration signal to judge the impact intensity of the electric drive system.

[0066] Specifically, the first vibration peak value X is read from the first vibration signal. 1max The first effective value X of the vibration when the electric drive system is struck 1rms The testing software automatically identifies the target vibration signal corresponding to the impact time period of the electric drive system from the first vibration signal, and automatically identifies the effective value from the target vibration signal to obtain the first vibration effective value. The ratio of the first vibration peak value to the first vibration effective value is then calculated. The zero-crossing rise peak factor C1 of the motor torque is obtained. The zero-crossing rise peak factor represents the impact intensity of the electric drive system when the motor torque rises to zero.

[0067] Reference Figure 4A This is a schematic diagram of the vibration signal processing of the motor torque zero-crossing rise in a vehicle electric drive system testing method provided in an embodiment of this application.

[0068] like Figure 4A As shown, Y1 is the first vibration signal, and Y2 is the torque signal indicating the change of motor torque from the target negative torque to the target positive torque. By processing Y1 and Y2 through the testing software, the first vibration peak X in the first vibration signal can be automatically identified. 1max The first effective value X of the vibration when the electric drive system is struck 1rms Thus, the zero-crossing peak rise factor of the motor torque can be calculated.

[0069] Similarly, the second vibration peak value X is read from the second vibration signal. 2max The second effective value X of the vibration when the electric drive system is struck 2rms The testing software automatically identifies the target vibration signal corresponding to the impact time period of the electric drive system from the second vibration signal, and automatically identifies the effective value from the target vibration signal to obtain the effective value of the second vibration. The ratio of the peak value of the second vibration to the effective value of the second vibration is then calculated. The zero-crossing drop peak factor C2 of the motor torque is obtained. The zero-crossing drop peak factor represents the impact intensity of the electric drive system when the motor torque drops to zero.

[0070] Reference Figure 4B This is a schematic diagram of the vibration signal processing for the zero-crossing vibration of the motor torque in a vehicle electric drive system testing method provided in an embodiment of this application.

[0071] like Figure 4B As shown, Y1 is the second vibration signal, and Y2 is the torque signal indicating the change of motor torque from the target positive torque to the target negative torque. By processing Y1 and Y2 through testing software, the second vibration peak value X in the second vibration signal can be automatically identified. 2max The second effective value X of the vibration when the electric drive system is struck 2rms Thus, the zero-crossing drop peak factor of the motor torque can be calculated.

[0072] After obtaining the zero-crossing rising peak factor and the zero-crossing falling peak factor, the impact intensity of the electric drive system when the motor torque crosses zero and rises or falls can be determined. Thus, the first torque change rate is adjusted according to the zero-crossing rising peak factor, and the second torque change rate is adjusted according to the zero-crossing falling peak factor.

[0073] According to the embodiments of this application, the zero-crossing rising peak factor and the zero-crossing falling peak factor of the motor torque are determined based on the ratio of the vibration peak value to the vibration effective value in the vibration signal. The zero-crossing rising peak factor and the zero-crossing falling peak factor determined by the ratio of the vibration peak value to the vibration effective value can more effectively characterize the impact intensity of the electric drive system when the motor torque crosses zero, thereby improving the accuracy of subsequent adjustments to the first torque change rate and the second torque change rate.

[0074] Optionally, the method includes: According to the first torque change rate, the motor torque of the electric drive system is controlled to change from the target negative torque to the target positive torque, and the first vibration signal of the electric drive system is collected to determine the corresponding zero-crossing rise peak factor based on the first vibration signal. The zero-crossing rise peak factor of the motor torque is determined based on the average value of the zero-crossing rise peak factor. According to the second torque change rate, the motor torque of the electric drive system is controlled to change from the target positive torque to the target negative torque, and the second vibration signal of the electric drive system is collected to determine the corresponding zero-crossing descent peak factor based on the second vibration signal; The zero-crossing descent peak factor of the motor torque is determined based on the average value of the zero-crossing descent peak factor.

[0075] Since the knocking during the switching of positive and negative torque in the electric drive is a transient phenomenon, the vibration data of each knock may have a large deviation. It is necessary to collect multiple vibration signals to comprehensively judge and confirm the knocking level of the electric drive system. Therefore, the embodiments of this application repeat the test process and calculate the average value of the zero-crossing rising peak factor and the average value of the zero-crossing falling peak factor corresponding to multiple tests to avoid the occasional influence of a single test.

[0076] Specifically, the process of repeatedly controlling the motor torque of the electric drive system to change from the target negative torque to the target positive torque according to the first torque change rate, and collecting the first vibration signal of the electric drive system, is repeated, and the zero-crossing rise peak factor corresponding to each execution is calculated. The average value C of the zero-crossing rise peak factor corresponding to each execution is calculated. 1avg The average value of the zero-crossing rise peak factor for each execution is taken as the zero-crossing rise peak factor C1 of the motor torque. In one example, the zero-crossing rise test process can be executed 5 times.

[0077] The process of repeatedly controlling the motor torque of the electric drive system to change from the target positive torque to the target negative torque according to the second torque change rate, and collecting the second vibration signal of the electric drive system, is performed. The zero-crossing descent peak factor corresponding to each execution is calculated. The average value C of the zero-crossing descent peak factor corresponding to each execution is calculated. 2avg The average value of the zero-crossing drop peak factor for each execution is taken as the zero-crossing drop peak factor C2 of the motor torque. In one example, the zero-crossing drop test process can be executed 5 times.

[0078] This application embodiment performs multiple zero-crossing tests on the electric drive system. The zero-crossing rising peak factor of the motor torque is determined by the average value of the zero-crossing rising peak factor obtained from multiple tests, and the zero-crossing falling peak factor of the motor torque is determined by the average value of the zero-crossing falling peak factor obtained from multiple tests. This avoids the occasional influence of a single test and improves the accuracy of the striking intensity when the motor torque crosses zero.

[0079] Optionally, adjusting the first torque change rate according to the zero-crossing rising peak factor and adjusting the second torque change rate according to the zero-crossing falling peak factor includes: If the zero-crossing rise peak factor is greater than the first factor threshold, then the first torque change rate is adjusted according to the ratio of the zero-crossing rise peak factor to the first factor threshold; and / or, If the zero-crossing descent peak factor is greater than the second factor threshold, the second torque change rate is adjusted according to the ratio of the zero-crossing descent peak factor to the second factor threshold.

[0080] In this embodiment, the zero-crossing rising peak factor and the zero-crossing falling peak factor are used to determine whether it is necessary to adjust the first torque change rate and / or the second torque change rate accordingly, so as to adjust the knocking intensity of the electric drive system when the motor torque crosses zero.

[0081] Specifically, if the zero-crossing rising peak factor is greater than the first factor threshold, the first torque change rate is adjusted according to the ratio of the zero-crossing rising peak factor to the first factor threshold; and / or, if the zero-crossing falling peak factor is greater than the second factor threshold, the second torque change rate is adjusted according to the ratio of the zero-crossing falling peak factor to the second factor threshold.

[0082] In one embodiment, the first factor threshold and the second factor threshold can be the same or different, and can be set according to actual needs in actual implementation.

[0083] In one example, both the first factor threshold and the second factor threshold are set to 10. When the zero-crossing rising peak factor is greater than 10, the first torque change rate needs to be adjusted, and / or, when the zero-crossing falling peak factor is greater than 10, the second torque change rate needs to be adjusted. In one embodiment of this application, the adjustment ratio is... The torque change rate is adjusted, where C is the zero-crossing peak factor greater than the corresponding factor threshold, 10 is the factor threshold, and A... a A represents the rate of change of torque before adjustment. b This is the adjusted torque change rate. For example, if the zero-crossing rise factor is greater than 10, then C is the zero-crossing rise factor, and A... a A represents the first torque change rate before adjustment. b This represents the adjusted first torque change rate.

[0084] This application embodiment identifies and judges the impact intensity of the electric drive system under the condition of zero-crossing torque by using the zero-crossing rising peak factor and the zero-crossing falling peak factor. When the zero-crossing rising peak factor is greater than the first factor threshold and / or the zero-crossing falling peak factor is greater than the second factor threshold, the corresponding torque change rate needs to be adjusted, thereby optimizing the impact intensity of the electric drive system under the condition of zero-crossing torque, so that the impact intensity is controlled within the acceptable range for the occupants, avoiding discomfort, and thus improving the driving comfort of the vehicle under acceleration and deceleration conditions.

[0085] Optionally, the method further includes: If the zero-crossing rising peak factor is less than or equal to the first factor threshold, and the zero-crossing falling peak factor is less than or equal to the second factor threshold, then the first torque change rate and the second torque change rate are output.

[0086] In this embodiment of the application, when the zero-crossing rising peak factor is less than or equal to the first factor threshold and the zero-crossing falling peak factor is less than or equal to the second factor threshold, it is determined that the impact intensity of the electric drive system under the zero-crossing motor torque condition is within the acceptable range for the occupants, and the test ends, and the first torque change rate and the second torque change rate are output.

[0087] In one example, the first torque change rate and the second torque change rate are output to the vehicle controller. The calibration parameters of the vehicle controller include torque slope control parameters within the motor torque range. The first and second torque change rates are used to calibrate the zero-crossing slope of the electric drive system torque. For example, within the motor torque range of -5Nm to 5Nm, a motor torque change rate of A=20Nm / s can be used to control the change in motor torque.

[0088] In this embodiment of the application, when the zero-crossing rising peak factor is less than or equal to the first factor threshold and the zero-crossing falling peak factor is less than or equal to the second factor threshold, it can be considered that the impact intensity of the electric drive system under the zero-crossing motor torque condition is within the acceptable range for the occupants. The zero-crossing motor torque condition of the vehicle's electric drive system can be controlled according to the current first torque change rate and second torque change rate, thereby improving the driving comfort of the vehicle under acceleration and deceleration conditions.

[0089] Example 2 To enable those skilled in the art to more clearly understand the vehicle electric drive system testing method provided in the embodiments of this application, through... Figure 7 The test method for the electric drive system of the vehicle shown in the embodiments of this application will be explained.

[0090] Reference Figure 5 This is a test flowchart of a vehicle electric drive system test method provided in an embodiment of this application.

[0091] Step 501: Install the electric drive system onto the electric drive test bench.

[0092] Step 502: Install a vibration sensor at the mounting point of the suspension bracket closest to the motor input gear transmission position in the electric drive system.

[0093] Step 503: Control the left and right half-shaft dynamometers of the electric drive test bench under the electric drive system to rotate at a speed of V, for example, the speed V is 75 r / min.

[0094] Step 504: Start the test and collect vibration sensor data.

[0095] Step 505: Control the motor torque from -T to T, changing it at a first torque change rate A1, and collect the first vibration signal. For example, from -10Nm to 10Nm, changing it at a first torque change rate of 40Nm / s, taking 0.5s.

[0096] Step 506: Control the motor torque from T to -T, varying it at a second torque change rate A2, and collect the second vibration signal. For example, from 10 Nm to -10 Nm, vary it at a second torque change rate of 20 Nm / s, taking 1 second.

[0097] Steps 507, 505 and 506 are repeated 5 times, then data acquisition is stopped.

[0098] Step 508: Set both the first factor threshold and the second factor threshold to 10, and determine whether it meets the requirement (C). 1avg ≤10)&&(C 2avg ≤10), that is, the average value C of the zero-crossing rising peak factor corresponding to each execution. 1avg Less than or equal to the first factor threshold, and the average value C of the corresponding zero-crossing descent peak factor for each execution. 2avg If the value is less than or equal to the second factor threshold, and if it does not meet the requirement, then A1 and / or A2 are reduced and the test is repeated until it meets the requirement (C). 1avg ≤10)&&(C 2avg ≤10). For example, analyzing the first vibration data of a certain execution yields X. 1max =1.8m / s 2 ,X 1rms =0.22m / s 2 The zero-crossing rising peak factor corresponding to this execution Analyze C1 five times and take the average to obtain C. 1avg =8, and similarly we get C. 2avg =12, determine C 1avg ≤10, but C 2avg >10, therefore A2 is reduced from 20 Nm / s to 10 Nm / s, and steps 704-708 are restarted for testing and analysis to obtain C. 1avg =8, C 2avg =7, then C 1avg ≤10 and C 2avg ≤10.

[0099] Step 509: Stop the test and output A1 and A2 to the vehicle controller. The vehicle controller calibrates the zero-crossing rise and fall slope of the electric drive system torque according to A1 and A2, which can effectively control the impact intensity of the electric drive system under low-speed acceleration and deceleration conditions of new energy vehicles.

[0100] This application embodiment simulates the operating state of the electric drive system under the conditions of motor torque rising and falling below zero, respectively, according to a first torque change rate and a second torque change rate. A first vibration signal and a second vibration signal are collected accordingly. The first vibration signal reflects the impact intensity of the electric drive system during the rising of motor torque above zero, and the second vibration signal reflects the impact intensity during the falling of motor torque below zero. By testing the electric drive system, the impact intensity under the condition of motor torque falling below zero can be identified in advance, thereby effectively shortening the development cycle of the electric drive system and reducing the cost of changes during development. This application embodiment adjusts the first and second torque change rates based on the test results to optimize the impact intensity of the electric drive system when the motor torque falls below zero, controlling it within an acceptable range for vehicle occupants to avoid discomfort and thus improve driving comfort during acceleration and deceleration.

[0101] This application also provides a vehicle electric drive system testing device 60, please refer to... Figure 6 ,include: The data acquisition module 610 is used to acquire the target negative torque, the target positive torque, the first torque change rate, and the second torque change rate; The first test module 620 is used to control the motor torque of the electric drive system to change from the target negative torque to the target positive torque according to the first torque change rate, and to collect the first vibration signal of the electric drive system, wherein the first vibration signal reflects the impact intensity of the electric drive system when the motor torque rises from zero. The second test module 630 is used to control the motor torque of the electric drive system to change from the target positive torque to the target negative torque according to the second torque change rate, and to collect the second vibration signal of the electric drive system, the second vibration signal reflecting the impact intensity of the electric drive system when the motor torque drops to zero; The data adjustment module 640 is used to adjust the first torque change rate and the second torque change rate according to the first vibration signal and the second vibration signal, respectively, so as to adjust the impact intensity of the electric drive system when the motor torque crosses zero.

[0102] Optionally, the data adjustment module 640 includes: The first processing submodule is used to determine the first vibration peak value and the first effective vibration value when the electric drive system is struck, based on the first vibration signal. The first factor determination submodule is used to determine the ratio of the first vibration peak value to the first vibration effective value, and obtain the zero-crossing rise peak factor of the motor torque. The zero-crossing rise peak factor represents the impact intensity of the electric drive system when the motor torque rises at zero. The second processing submodule is used to determine the second vibration peak value and the second vibration effective value when the electric drive system is struck, based on the second vibration signal. The second factor determination submodule is used to determine the ratio of the second vibration peak value to the second vibration effective value, and to obtain the zero-crossing drop peak factor of the motor torque. The zero-crossing drop peak factor represents the impact intensity of the electric drive system when the motor torque drops to zero. The rate of change adjustment submodule is used to adjust the first torque rate of change according to the zero-crossing rising peak factor, and to adjust the second torque rate of change according to the zero-crossing falling peak factor.

[0103] Optionally, the device includes: The first repeatable test module is used to control the motor torque of the electric drive system to change from the target negative torque to the target positive torque according to the first torque change rate, and to collect the first vibration signal of the electric drive system to determine the corresponding zero-crossing rise peak factor based on the first vibration signal. The first mean determination module is used to determine the zero-crossing rise peak factor of the motor torque based on the average value of the zero-crossing rise peak factor. The second repeat test module is used to control the motor torque of the electric drive system to change from the target positive torque to the target negative torque according to the second torque change rate, and to collect the second vibration signal of the electric drive system to determine the corresponding zero-crossing descent peak factor based on the second vibration signal. The second mean determination module is used to determine the zero-crossing descent peak factor of the motor torque based on the average value of the zero-crossing descent peak factor.

[0104] Optionally, the rate of change adjustment submodule is specifically used for: If the zero-crossing rise peak factor is greater than the first factor threshold, then the first torque change rate is adjusted according to the ratio of the zero-crossing rise peak factor to the first factor threshold; and / or, If the zero-crossing descent peak factor is greater than the second factor threshold, the second torque change rate is adjusted according to the ratio of the zero-crossing descent peak factor to the second factor threshold.

[0105] Optionally, the rate of change adjustment submodule is further configured to: If the zero-crossing rising peak factor is less than or equal to the first factor threshold, and the zero-crossing falling peak factor is less than or equal to the second factor threshold, then the first torque change rate and the second torque change rate are output.

[0106] Optionally, the electric drive system includes a suspension bracket, the electric drive system is located on a preset electric drive test bench, and the electric drive test bench is used to control the change of the motor torque; The motor includes an input gear; A vibration sensor is arranged at the target suspension bracket mounting point closest to the input gear transmission position of the motor in the electric drive system. The vibration sensor is used to collect the first vibration signal and the second vibration signal.

[0107] Optionally, the electric drive test bench includes a left half-shaft and a right half-shaft, and the device includes: The vehicle speed acquisition module is used to acquire the test speed of the vehicle. The rotational speed determination module is used to determine the test rotational speeds of the left and right half-shafts of the electric drive test bench based on the test vehicle speed. The system testing module is used to test the electric drive system when the left and right half-shafts of the electric drive test bench rotate at the test speed.

[0108] This application also provides an electronic device 70, please refer to... Figure 7 It includes a processor 710 and a memory 720, wherein the memory 710 is used to store computer programs; the processor 720 is used to execute the programs stored in the memory 710 to implement the vehicle electric drive system testing method described in any embodiment of this application.

[0109] This application also provides a vehicle that includes the electronic equipment described in this application.

[0110] In this application, "multiple" refers to two or more.

[0111] In this application, unless otherwise expressly defined, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0112] The terms “first,” “second,” “third,” “fourth,” etc., in this application (if present) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0113] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0114] Unless otherwise specified, all steps in this application may be performed sequentially or randomly. For example, if the method includes steps A and B, it means that the method may include steps A and B performed sequentially, or it may include steps B and A performed sequentially. For example, if the method may also include step C, it means that step C may be added to the method in any order. For example, the method may include steps A, B, and C, or it may include steps A, C, and B, or it may include steps C, A, and B, etc.

[0115] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for testing an electric drive system of a vehicle, characterized in that, The electric drive system includes a motor, the motor having a corresponding motor torque, and the method includes: Acquire test parameters, including target negative torque, target positive torque, first torque change rate, and second torque change rate; According to the first torque change rate, the motor torque of the electric drive system is controlled to change from the target negative torque to the target positive torque, and a first vibration signal of the electric drive system is collected. The first vibration signal reflects the impact intensity of the electric drive system when the motor torque rises from zero. According to the second torque change rate, the motor torque of the electric drive system is controlled to change from the target positive torque to the target negative torque, and a second vibration signal of the electric drive system is collected. The second vibration signal reflects the impact intensity of the electric drive system when the motor torque drops to zero. The first torque change rate is adjusted according to the first vibration signal, and the second torque change rate is adjusted according to the second vibration signal, so as to adjust the knocking intensity of the electric drive system when the motor torque crosses zero.

2. The test method for the electric drive system of a vehicle according to claim 1, characterized in that, The steps of adjusting the first torque change rate based on the first vibration signal and adjusting the second torque change rate based on the second vibration signal include: The first vibration peak value and the first effective vibration value when the electric drive system is struck are determined based on the first vibration signal. The ratio of the first vibration peak value to the first vibration effective value is determined to obtain the zero-crossing rise peak factor of the motor torque, wherein the zero-crossing rise peak factor represents the impact intensity of the electric drive system when the motor torque rises at zero. The second vibration peak value and the second effective vibration value when the electric drive system is struck are determined based on the second vibration signal. The ratio of the second vibration peak value to the second vibration effective value is determined to obtain the zero-crossing drop peak factor of the motor torque, which represents the knocking intensity of the electric drive system when the motor torque drops to zero. The first torque change rate is adjusted according to the zero-crossing rising peak factor, and the second torque change rate is adjusted according to the zero-crossing falling peak factor.

3. The test method for the electric drive system of a vehicle according to claim 2, characterized in that, The method includes: According to the first torque change rate, the motor torque of the electric drive system is controlled to change from the target negative torque to the target positive torque, and the first vibration signal of the electric drive system is collected to determine the corresponding zero-crossing rise peak factor based on the first vibration signal. The zero-crossing rise peak factor of the motor torque is determined based on the average value of the zero-crossing rise peak factor. According to the second torque change rate, the motor torque of the electric drive system is controlled to change from the target positive torque to the target negative torque, and the second vibration signal of the electric drive system is collected to determine the corresponding zero-crossing descent peak factor based on the second vibration signal; The zero-crossing descent peak factor of the motor torque is determined based on the average value of the zero-crossing descent peak factor.

4. The test method for the electric drive system of a vehicle according to claim 2, characterized in that, The step of adjusting the first torque change rate according to the zero-crossing rising peak factor and adjusting the second torque change rate according to the zero-crossing falling peak factor includes: If the zero-crossing rise peak factor is greater than the first factor threshold, then the first torque change rate is adjusted according to the ratio of the zero-crossing rise peak factor to the first factor threshold; and / or, If the zero-crossing descent peak factor is greater than the second factor threshold, the second torque change rate is adjusted according to the ratio of the zero-crossing descent peak factor to the second factor threshold.

5. The test method for the electric drive system of a vehicle according to claim 4, characterized in that, The method further includes: If the zero-crossing rising peak factor is less than or equal to the first factor threshold, and the zero-crossing falling peak factor is less than or equal to the second factor threshold, then the first torque change rate and the second torque change rate are output.

6. The test method for the electric drive system of a vehicle according to claim 1, characterized in that, The electric drive system includes a suspension bracket, and the electric drive system is located on a preset electric drive test bench, which is used to control the change of the motor torque; The motor includes an input gear; A vibration sensor is arranged at the target suspension bracket mounting point closest to the input gear transmission position of the motor in the electric drive system. The vibration sensor is used to collect the first vibration signal and the second vibration signal.

7. The test method for the electric drive system of a vehicle according to claim 6, characterized in that, The electric drive test bench includes a left half-shaft and a right half-shaft. After obtaining the target negative torque, target positive torque, first torque change rate, and second torque change rate, the method includes: Obtain the test speed of the vehicle; The test speeds of the left and right half-shafts of the electric drive test bench are determined based on the test vehicle speed. The electric drive system is tested when the left and right half-shafts of the electric drive test bench rotate at the test speed.

8. A testing device for an electric drive system of a vehicle, characterized in that, The electric drive system includes a motor, the motor having a corresponding motor torque, and the device includes: The data acquisition module is used to acquire the target negative torque, the target positive torque, the first torque change rate, and the second torque change rate; The first test module is used to control the motor torque of the electric drive system to change from the target negative torque to the target positive torque according to the first torque change rate, and to collect the first vibration signal of the electric drive system, wherein the first vibration signal reflects the impact intensity of the electric drive system when the motor torque rises from zero. The second test module is used to control the motor torque of the electric drive system to change from the target positive torque to the target negative torque according to the second torque change rate, and to collect the second vibration signal of the electric drive system, the second vibration signal reflecting the impact intensity of the electric drive system when the motor torque drops to zero; The data adjustment module is used to adjust the first torque change rate and the second torque change rate according to the first vibration signal and the second vibration signal, respectively, so as to adjust the impact intensity of the electric drive system when the motor torque crosses zero.

9. An electronic device, characterized in that, Including processor and memory, among which Memory, used to store computer programs; A processor for executing a program stored in a memory to implement the test method for the electric drive system of the vehicle as described in any one of claims 1-7.

10. A vehicle, characterized in that, It includes the electronic device as described in claim 9.

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