Method for evaluating the overall driving energy of a vehicle in a wind tunnel and storage medium

Abstract

A method and storage medium for evaluating the overall driving energy of a vehicle in a wind tunnel, the method can include estimating the change in fuel efficiency according to the change in the vehicle components, thereby facilitating accurate measurement of driving energy.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method of evaluating the overall running energy of a vehicle in a wind tunnel, which facilitates accurate measurement of the running energy. More particularly, the present invention relates to a method of evaluating the overall running energy of a vehicle in a wind tunnel, which more accurately estimates the change in fuel efficiency according to the change in the vehicle components. BACKGROUND

[0002] In the certification process of the fuel efficiency of a vehicle, actual road coasting is implemented. As shown in FIG. 1, in the coasting test, a test vehicle that is high-speed driven on a straight road without a slope is put in neutral. The coasting test is designed to measure the change in the vehicle speed within a certain time interval or the time taken to decelerate in a certain speed section. The data obtained in the coasting test is analyzed to determine the running resistance acting on the test vehicle. Figure 1

[0003] There are several problems to be solved in the existing coasting test. First, since many interference factors such as temperature, wind speed, humidity, road conditions, and drivers, the error is high, and it is necessary to repeat the test back and forth to ensure the normality of the data, which thus increases the test time. In the coasting test, the external wind speed and the vehicle speed are measured, and it is necessary to install an anemometer and a speedometer on the test vehicle, which can deform the air resistance. Most importantly, the contributions of the acceleration resistance and the deceleration resistance cannot be measured.

[0004] Therefore, there is a need for a method of evaluating the running resistance of a vehicle in a novel way.

[0005] The information included in the Background section of the present invention is only for the purpose of enhancing the understanding of the overall background of the present invention, and it cannot be regarded as recognition that this information constitutes the prior art known to those skilled in the art or any form of suggestion. SUMMARY

[0006] The various aspects of the present invention aim to provide an improved method of evaluating the running energy, which provides enhanced data precision and accuracy.

[0007] ​According to various exemplary embodiments of the present application, a method of evaluating an overall running energy of a vehicle in a wind tunnel includes: placing the vehicle in the wind tunnel; changing a vehicle speed by rotating wheels of the vehicle to obtain a plurality of constant speed sections and a plurality of variable speed sections, wherein the vehicle speed is kept constant in each constant speed section, the plurality of constant speed sections have different constant speeds from each other, and the vehicle speed is increased or decreased in the plurality of variable speed sections between adjacent constant speed sections; measuring and collecting an applied force in each constant speed section and an applied force in each variable speed section; separating the applied force in each constant speed section from the applied force in each variable speed section; determining a running energy of the constant speed section based on the applied force separated in each constant speed section, and determining a running energy of the variable speed section based on the applied force separated in each variable speed section; and obtaining an overall running energy of the vehicle based on the running energy of the constant speed section and the running energy of the variable speed section.

[0008] According to various exemplary embodiments of the present application, a method of evaluating an overall running energy of a vehicle in a wind tunnel, wherein a test vehicle is located in a wind tunnel provided with a wheel rotation device, and wheels of the test vehicle are rotated by the wheel rotation device, the method includes: a preheating step of performing a preheating of the test vehicle; a deceleration evaluation step of evaluating a deceleration of the test vehicle after the preheating step; a section separation step of separating data obtained from the deceleration evaluation step into constant speed sections and variable speed sections; a running energy determination step of determining a running energy of the constant speed sections and a running energy of the variable speed sections; and an overall running energy determination step of obtaining an overall running energy of the vehicle based on the determined running energy of the constant speed sections and the determined running energy of the variable speed sections.

[0009] Other aspects and exemplary embodiments of the present application are discussed below.

[0010] The above and other features of the present application are discussed below.

[0011] It should be understood that the term "vehicle" or "of a vehicle" or other similar terms used herein generally include motor vehicles such as passenger cars (including sport utility vehicles (SUVs), public vehicles, trucks, various commercial vehicles), water vehicles (including various ships, steamers), airplanes, and the like, and include hybrid vehicles, electric vehicles, plug-in hybrid vehicles, hydrogen-powered vehicles, and other alternative fuel (e.g., fuel derived from resources other than petroleum) vehicles. As referred to herein, a hybrid vehicle is a vehicle having two or more power sources (e.g., a gasoline-powered and electric-powered vehicle).

[0012] The methods and apparatus of the present application have other features and advantages that will be apparent from a consideration of the drawings and detailed description of the application, in conjunction with the appended claims. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a graph depicting a prior coastdown test;

[0014] Figure 2 is a flowchart illustrating a method of evaluating the overall road energy of a vehicle in a wind tunnel according to various exemplary embodiments of the present application;

[0015] Figure 3 is a schematic diagram illustrating a ground stimulation device in a wind tunnel in which the method of evaluating the overall road energy of a vehicle in a wind tunnel according to various exemplary embodiments of the present application is performed.

[0016] Figure 4 is a graph of measured data in a pre-heat step of the method of evaluating the overall road energy of a vehicle in a wind tunnel according to various exemplary embodiments of the present application.

[0017] Figure 5 is a graph of measured data in a deceleration step of the method of evaluating the overall road energy of a vehicle in a wind tunnel according to various exemplary embodiments of the present application.

[0018] Figure 6A and Figure 6B is a graph of measured data of a base wheel having prior features and an aerodynamic wheel having improved features evaluated by the method of evaluating the overall road energy of a vehicle in a wind tunnel according to various exemplary embodiments of the present application; and

[0019] Figure 7 is a graph of measured data of a base wheel having prior features and an aerodynamic wheel having improved features evaluated by the method of evaluating the overall road energy of a vehicle in a wind tunnel according to various exemplary embodiments of the present application.

[0020] It is to be understood that the drawings are not necessarily to scale, and that certain features that are represented in slightly simplified form have been purposefully omitted for the sake of clarity. Specific design features of the application as included herein (e.g., including specific dimensions, orientations, locations, and shapes) will be determined in part by the particular intended application and use environment.

[0021] In the drawings, like reference numerals refer to like parts throughout the various drawings. DETAILED DESCRIPTION

[0022] Reference will now be made in detail to various embodiments of the present application, examples of which are illustrated in the accompanying drawings and described below. While the present application will be described in conjunction with the exemplary embodiments, it should be understood that the present application is not limited to those exemplary embodiments. On the contrary, the present application is intended to cover various alternatives, modifications, equivalents and other embodiments that can be included within the spirit and scope of the present application as defined by the appended claims.

[0023] Hereinafter, exemplary embodiments of the present application will be described in detail with reference to the accompanying drawings. The specific construction or function described in the exemplary embodiments of the present application is for illustrative purposes only. Embodiments according to the concept of the present application can be implemented in various forms and it should be understood that they should not be interpreted as being limited to the exemplary embodiments described in the specification, but include all modifications, equivalents or alternatives included within the spirit and scope of the present application.

[0024] It will be understood that, although the terms "first", "second", etc. can be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element discussed below could be termed a second element without departing from the teachings of the present application. Similarly, a second element could be termed a first element.

[0025] It will be understood that when an element is referred to as being "coupled" or "connected" to another element, it can be directly coupled or connected to the other element or intervening elements can be present. In contrast, when an element is referred to as being "directly coupled" or "directly connected" to another element, there are no intervening elements present. Other expressions used herein, such as "between", "directly between", "adjacent to", or "directly adjacent to", should be interpreted in a like fashion.

[0026] Throughout the specification, like drawing reference numerals refer to like elements throughout the specification. Also, as used in the specification, the term "includes" means includes but is not limited to, the term "comprising" means comprising but not limited to, and the term "have" and "has" means have but not limited to. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises", "comprising", "includes" and / or "including", when used herein, specify the presence of stated features, steps, operations, and / or elements, but do not preclude the presence or addition of one or more other features, steps, operations, and / or elements thereof.

[0027] Hereinafter, the present application will be described in detail with reference to the accompanying drawings.

[0028] As Figure 2As shown, the method of evaluating the comprehensive running energy of a vehicle in a wind tunnel according to various exemplary embodiments of the present application: includes a step S10 of performing preheating, a step S20 of evaluating deceleration, a step S30 of evaluating acceleration, a step S40 of separating sections, a step S50 of determining running energy, and a step S60 of acquiring comprehensive running energy.

[0029] Referring to Figure 3 , the evaluation method according to various exemplary embodiments of the present application can be implemented in a wind tunnel 2. A fan or the like configured to adjust the speed of air is provided in the wind tunnel 2. Since the evaluation method of the present application can be performed in the wind tunnel 2, the amount of time required to take measurements can be greatly reduced, and errors caused by disturbances can be minimized. Thus, the precision of test results can be improved.

[0030] A ground stimulation device 4 is provided in the wind tunnel 2. The ground stimulation device 4 includes a wheel rotation device 14 including a drum 114 and a belt 214. The drum 114 is configured to be rotatable by a driving force applied from an external source, and the belt 214 is disposed on the outer circumference of the drum 114 and is configured to be rotatable with the drum 114. The wheel of the test vehicle V is configured to be in contact with the belt 214 that supports the wheel.

[0031] The wheel rotation device 14 is housed in a measurement platform 24. The measurement platform 24 is configured to be supported from the ground by air bearings 34 to minimize the effects of other frictional factors. In addition, the test vehicle V is supported and connected by one or more vertical struts 44 formed in the ground stimulation device 4.

[0032] The wheel rotation device 14 is provided with a force measuring portion 54 that measures the force with which the drum 114 drives the belt 214. As a non-limiting example, the force measuring portion 54 can include a load cell.

[0033] As Figure 4 shown, the step S10 of performing preheating is to minimize errors caused by deformation of the tire before evaluating the comprehensive running energy. According to various exemplary embodiments of the present application, in the step S10 of preheating, the wheel of the test vehicle V is rotated by the wheel rotation device 14 to raise the temperature of the tire. According to various exemplary embodiments of the present application, the wind speed in the wind tunnel 2 is set to 0 kilometers per hour (km / h), and the wheel is rotated at a rotational speed of 140 km / h or higher in a fixed manner, so that the temperature of the tire is rapidly raised. This can raise the temperature of the tire as quickly as possible (i.e., as much as possible to reduce the amount of time taken to perform the step S10 of preheating).

[0034] Meanwhile, in the step S10 of warming-up, the force to drive the wheels of the test vehicle V can be measured by the force of the belt 214 driving the wheel rotation device 14, and the force can be measured by the force measuring section 54. Further, according to various exemplary embodiments of the present application, the force and speed data can be taken at a frequency of 10 Hertz (Hz) or more to collect a sufficient amount of data. The step S10 of warming-up is terminated when the error of the force measurement obtained in a predetermined first time period is maintained within a certain range. According to various exemplary embodiments of the present application, the predetermined first time period is 200 seconds, and the error range of the force is ±1 N. That is, the step S10 of warming-up is terminated when the error of the applied force measured by the force measuring section 54 in 200 seconds is maintained within ±1 N.

[0035] In the step S20 of evaluating deceleration and the step S30 of evaluating acceleration, the force applied in each constant speed section and the force applied in each variable speed section are measured for certain speed sections. According to various exemplary embodiments of the present application, the step S20 of evaluating deceleration is performed before the step S30 of evaluating acceleration. According to various exemplary embodiments of the present application, the step S30 of evaluating acceleration is implemented before the step S20 of evaluating deceleration.

[0036] Figure 5 The measured data in the step S20 of evaluating deceleration is described. The step S30 of evaluating acceleration is performed in a similar manner to the step S20 of evaluating deceleration except that the speed is increased for each speed section, and thus the step S20 of evaluating deceleration will be representatively described herein.

[0037] Referring to Figure 5 In the steps S20 and S30, the speed of the wheels and the force applied to rotate the wheels are measured at a preset speed interval. As a non-limiting example, the preset speed interval can be 10 km / h as shown in Figure 5 As a non-limiting example, the preset speed interval can be 5 km / h or 20 km / h. The preset speed interval is not limited to these values provided as non-limiting examples, and the preset speed interval can be changed as necessary.

[0038] According to various exemplary embodiments of the present application, the data in each constant speed section (i.e., a section in which the constant speed is maintained) is measured for a preset time or more. As a non-limiting example, the preset time can be 10 seconds.

[0039] In the step S20 of evaluating deceleration, it is preferable to measure from the vehicle speed higher than the maximum speed in the fuel efficiency certification mode. For example, the reference vehicle speed of the World Light-duty Vehicle Test Cycle (WLTC) is 140 km / h. In the experiment provided in Figure 5 the measurement is started at a vehicle speed of 140 km, but the vehicle speed is not limited to this speed value.

[0040] In steps S20 and S30, the force in each constant speed section (i.e., the force of the roller 114 rotating the belt 214) can be measured by the force measuring unit 54. Rolling resistance, wheel rotation resistance, acceleration resistance, and deceleration resistance can be derived from the measured force. In addition, air resistance is measured by the vertical support 44 of the ground stimulation device 4 and the measuring platform 24.

[0041] In step S40, the force measured in step S20 (evaluating deceleration) or step S30 (evaluating acceleration) is separated into forces in the constant speed segment and forces in the variable speed segment. When the preset speed interval is 10 km / h, the variable speed segments are classified in 10 km / h intervals. According to various exemplary embodiments of the invention, a preset force difference is considered to determine the criteria for classifying the forces in the constant speed segment and the forces in the variable speed segment. For example, when an applied force of approximately 140 N is measured in the 120 km / h speed segment, values ​​in the range of 135 N to 139 N are excluded from the constant speed segment at 120 km / h. These values ​​are illustrative.

[0042] In step S50 of determining the driving energy, the required driving energy is determined based on the forces in the constant speed section and the variable speed section separated in step S40 of the separation section. Step S50 of determining the driving energy includes step S52 of determining the driving energy in the constant speed section and step S54 of determining the driving energy in the variable speed section.

[0043] In step S52, determining the driving energy in the constant speed segment is achieved by measuring the force F in each constant speed segment. c The average wheel speed v avg,c and the required time t c Multiply to obtain the driving energy E in each constant speed section. c .

[0044] [Formula 1]

[0045] E c =F c ·v avg，C ·t C

[0046] In step S54, in determining the travel energy in the shift section, force data of the shift section falling within a certain value range (as a non-limiting example, approximately 5 N) compared to the constant speed section is excluded. These excluded data values are basically included in the next constant speed section. However, even if the data value is within the 5 N range, when the speed at the force fails to reach the speed in the next adjacent speed section, the data value is rather included as the force in the shift section. Referring to the above example, in the case of a shift section in which deceleration from the constant speed section of 120 km / h (measured force: approximately 140 N) to the constant speed section of 110 km / h (measured force: approximately 138 N) is performed, when the travel energy in the shift section is determined, data values within the range of 135 N to 140 N (5 N range of 140 N) are excluded. However, even if the force measurement is within the above range of 135 N to 140 N, if the speed of the current force measurement fails to reach the speed of the next constant speed section (i.e., the speed section of 110 km / h), the current force measurement is included in the determination of the force as the shift section between 120 km / h and 110 km / h. This example is provided to aid understanding.

[0047] The travel energy E in the shift section is obtained by multiplying the force F of each shift section obtained as above v by the average value V of the wheel speed of each time as provided in Equation 2 below avg,v and the time t v . v .

[0048] [Equation 2]

[0049] E v = F v · v avg，v t v

[0050] Meanwhile, when there is an unmeasured section in the conversion of the travel energy in the constant speed section and the shift section, the travel energy in the unmeasured section is determined by a regression equation between the speed and the applied force.

[0051] In step S60 of acquiring the comprehensive travel energy, the comprehensive travel energy is determined based on the determined travel energy of the constant speed section and the travel energy of the shift section. The comprehensive travel energy is determined by adding the travel energy used during deceleration or acceleration to the travel energy in the constant speed section, and the deceleration energy or the acceleration energy is increased by determining the energy used at 10 km / h section intervals. Exemplary deceleration energy values for each speed section are given in Table 1.

[0052]

[0053]

[0054] Table 1

[0055] As Figure 6A and Figure 6B As shown in the table 1, the fuel efficiency after applying the air dynamic wheel 20 is evaluated according to various exemplary embodiments of the present application by comparing the base wheel 10 having the existing characteristics with the air dynamic wheel 20 having the improved characteristics.

[0056] Table 2 shows the measurement items and their corresponding values with respect to the base wheel 10 and the air dynamic wheel 20; Figure 7 The driving energy graph according to the application of the base wheel 10 and the air dynamic wheel 20 is shown. In Figure 7 In the table 2, the "Base Wheel" indicates the driving energy of the base wheel 10, and the "HEV Wheel" indicates the driving energy of the air dynamic wheel 20.

[0057]

[0058]

[0059] Table 2

[0060] As can be seen from the above table 2, the air dynamic performance of the air dynamic wheel 20 is improved to have a positive effect on the fuel efficiency, but, in terms of the weight and inertia, the air dynamic wheel 20 has a negative effect on the fuel efficiency. That is, according to the existing evaluation method, when the air dynamic wheel 20 is applied, it is not clear whether the overall fuel efficiency is improved, and it is difficult to collect quantitative data according to the speed due to the tire deformation.

[0061] On the other hand, according to various exemplary embodiments of the present application, it is found that the integrated driving energy is reduced by about 208 kJ. That is, by the evaluation method according to various exemplary embodiments of the present application, quantitative data can be obtained and it can be determined whether the integrated fuel efficiency is improved regardless of the fuel efficiency conflicting factors.

[0062] The method of evaluating the integrated driving energy of a vehicle in a wind tunnel according to the present application has the advantages of significantly improving the driving energy measurement accuracy and reducing the measurement time since the interference factors are reduced in measuring the integrated driving energy compared to the existing evaluation method.

[0063] In addition, according to various exemplary embodiments of the present application, since the anemometer or the speedometer is not installed on the test vehicle, the air resistance deformation can be avoided, and the acceleration / deceleration resistance can be measured. Therefore, it can be quantitatively measured whether the final fuel efficiency is improved with respect to various conflicting fuel efficiency improvement plans.

[0064] According to various exemplary embodiments of the present application, it is possible to accurately measure the amount of improvement in applied energy and fuel efficiency with respect to the rotational part and the wheel / tire part that are deformed with respect to speed, which has been difficult to measure so far. In addition, according to various exemplary embodiments of the present application, it is possible to quantitatively measure the final fuel efficiency improvement effect with respect to all fuel efficiency improvement plans according to the changes in various parts of the vehicle.

[0065] According to various aspects of the present application, there is provided a method of evaluating the overall running energy of a vehicle in a wind tunnel, which can minimize the influence of disturbance factors through measurement in the wind tunnel, compared to the existing method.

[0066] According to various aspects of the present application, there is provided a method of evaluating the overall running energy of a vehicle in a wind tunnel, which can improve data accuracy and reduce measurement time through measurement in the wind tunnel.

[0067] According to various aspects of the present application, there is provided a method of evaluating the overall running energy of a vehicle in a wind tunnel, which can measure acceleration resistance and deceleration resistance.

[0068] According to various aspects of the present application, the method of evaluating the overall running energy of a vehicle in a wind tunnel can accurately measure the amount of improvement in applied energy and fuel efficiency due to changes in parts of the vehicle.

[0069] In various exemplary embodiments of the present application, a controller can perform the method of evaluating the overall running energy of a vehicle in a wind tunnel.

[0070] In addition, the term related to a control device such as "controller", "control unit", "control means", or "control module" means a hardware device including a memory and a processor configured to perform one or more steps interpreted as an algorithm structure. The memory stores the algorithm steps, and the processor performs the algorithm steps to perform one or more processes of the method according to various exemplary embodiments of the present application. The control device according to exemplary embodiments of the present application can be implemented by a non-volatile memory configured to store data for controlling the operation of various parts of the vehicle or a software command for performing an algorithm, and a processor configured to perform the above operation using the data stored in the memory. The memory and the processor can be separate chips. Alternatively, the memory and the processor can be integrated in a single chip. The processor can be implemented as one or more processors. The processor can include various logic circuits and operation circuits, can process data according to a program provided from the memory, and can generate a control signal according to the processing result.

[0071] The control device can be at least one microprocessor operated by a predetermined program, which can include a series of commands for performing the method included in the aforementioned various exemplary embodiments of the present application.

[0072] The aforementioned application can also be embodied as computer readable codes on a computer readable recording medium. The computer readable recording medium is any data storage device that can store data which can be thereafter read by a computer system. Examples of the computer readable recording medium include a hard disk drive (HDD), a solid state disk (SSD), a silicon disk drive (SDD), a read-only memory (ROM), a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc., and is implemented as a carrier wave (e.g., transmission through the Internet).

[0073] In the various exemplary embodiments of the present application, each of the above-described operations can be performed by a control device, and the control device can be configured by a plurality of control devices or an integrated single control device.

[0074] In the various exemplary embodiments of the present application, the control device can be implemented in the form of hardware or software, or can be implemented in a combination of hardware and software.

[0075] For the convenience of explanation and accurate definition of the appended claims, the terms "above", "below", "inner", "outer", "upper", "lower", "upward", "downward", "front", "rear", "back", "interior", "exterior", "inward", "outward", "internal", "external", "inside", "outside", "forward", and "rearward" are used to describe the features of the exemplary embodiments with reference to the positions as shown in the drawings. It will also be understood that the term "connected" or its derivatives refers both to direct and indirect connections.

[0076] In addition, the term "fixed connection" means that the members of the fixed connection always rotate at the same speed. In addition, the term "selectively connectable" means that "when the selectively connectable members are not engaged with each other, the selectively connectable members rotate separately, when the selectively connectable members are engaged with each other, the selectively connectable members rotate at the same speed, and when at least one of the selectively connectable members is a stationary member and the remaining selectively connectable members are engaged to the stationary member, the selectively connectable members are stationary".

[0077] The foregoing description of specific exemplary embodiments of the application has been presented for the purposes of illustration and description. They are not intended to be exhaustive or to limit the application to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the application and their practical application to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present application, and various alternatives and modifications thereof. It is intended that the scope of the application be defined by the claims appended hereto and their equivalents.

Claims

1. A method for evaluating the overall driving energy of a vehicle in a wind tunnel, the method comprising: The vehicle is placed in the wind tunnel; The vehicle speed is changed by rotating the wheels of the vehicle to obtain multiple constant speed segments and multiple variable speed segments, wherein the vehicle speed remains constant in each constant speed segment, the multiple constant speed segments have different constant speeds from each other, and the vehicle speed is increased or decreased in the multiple variable speed segments between adjacent constant speed segments. The applied force for rotating the wheel is measured and collected in each of the plurality of constant speed sections and in each of the plurality of variable speed sections; Separate the applied force in each of the plurality of constant speed sections from the applied force in each of the plurality of variable speed sections; The driving energy of the plurality of constant speed sections is determined based on the separately applied force in each of the plurality of constant speed sections, and the driving energy of the plurality of variable speed sections is determined based on the separately applied force in each of the plurality of variable speed sections; and The vehicle's overall driving energy is obtained based on the driving energy in the multiple constant speed ranges and the driving energy in the multiple variable speed ranges.

2. The method according to claim 1, wherein, The wind tunnel includes: A wheel rotating device is configured to rotate the wheels of the vehicle; and A force measuring unit is configured to measure the applied force by measuring the driving force, and the wheel rotating device rotates the wheel by the driving force.

3. The method according to claim 1, further comprising: Before obtaining the plurality of constant speed sections and the plurality of variable speed sections, the wheels are preheated, in which the wheels of the vehicle are rotated at a constant speed for a predetermined period of time and the applied force used to rotate the wheels is measured and collected.

4. The method according to claim 3, wherein, During the preheating of the wheel, the wind speed in the wind tunnel is set to zero, and the wheel is rotated at the constant speed.

5. The method according to claim 3, wherein, The preheating process is terminated when the measured force change remains within a predetermined range for a preset time period.

6. The method according to claim 1, wherein, Each of the plurality of constant speed sections is arranged to be spaced apart by a preset speed interval, and the speed of the wheel maintained in each of the plurality of constant speed sections is measured for a preset time or for a time longer than the preset time.

7. The method according to claim 6, wherein, The applied force in each of the plurality of constant speed sections is separated from the applied force in each of the plurality of variable speed sections according to a preset force difference.

8. The method according to claim 7, wherein, The multiple constant speed sections include: In the first constant speed section, the first speed of the wheel is maintained and a first force is applied to make the wheel rotate; The second constant speed section, wherein a second speed is maintained that is smaller than the first speed by the preset speed interval, and a second force smaller than the first force is applied to rotate the wheel; and In the first gear shift section, the first speed decreases to the second speed. The magnitude of the force measured in the first speed change section is within a range between the first force and the second force, and also includes a magnitude lower than the second force.

9. The method according to claim 8, wherein, The measured force values ​​that fall within the range of the first force and the preset lower limit force are excluded from the forces in the first gear shift section, and the preset lower limit force is obtained by subtracting the preset force difference from the first force.

10. The method according to claim 9, wherein, When the speed at which one of the measured force values ​​excluded from the first gear shift section is measured is greater than the second speed, the measured force value is included in the force in the first gear shift section.

11. The method according to claim 1, wherein, When determining the driving energy in the plurality of constant speed segments, the driving energy in each constant speed segment is obtained by multiplying the applied force, the average wheel speed, and the time in each constant speed segment.

12. The method according to claim 1, wherein, When determining the driving energy in a gear shift segment, the driving energy is determined by multiplying the applied force in each gear shift segment by the average wheel speed at each time and the time.

13. The method according to claim 1, wherein, The combined driving energy is determined by adding the driving energy used during deceleration or acceleration to the driving energy in the constant speed section.

14. A non-transitory computer-readable storage medium having a program recorded thereon for performing the method according to claim 1.

15. A method for evaluating the comprehensive driving energy of a vehicle in a wind tunnel, wherein, The test vehicle is located in the wind tunnel equipped with a wheel rotation device, and the wheels of the test vehicle are rotated by the wheel rotation device, the method comprising: Perform preheating of the test vehicle; Assess the deceleration of the test vehicle; The data obtained from the deceleration assessment of the test vehicle will be separated into multiple constant speed ranges and variable speed ranges; Determine the driving energy of the multiple constant speed sections and the driving energy of the variable speed sections; and The vehicle's overall driving energy is obtained based on the driving energy determined in the multiple constant speed ranges and the driving energy determined in the variable speed ranges.

16. The method according to claim 15, wherein, During the preheating of the wheel, the wind speed in the wind tunnel is set to zero, and the wheel is rotated at a constant speed.

17. The method of claim 15, further comprising: The acceleration of the test vehicle is evaluated before or after the deceleration of the test vehicle.

18. The method of claim 15, wherein, The assessment of the deceleration of the test vehicle includes: The plurality of constant speed sections and the plurality of variable speed sections are arranged such that, within each of the constant speed sections, the constant speed of the wheel is maintained for a predetermined time period, and the variable speed sections are arranged between the plurality of constant speed sections, in which the speed of the wheel is reduced; and The force applied in each of the multiple constant speed sections and the force applied in the variable speed sections are measured.

19. The method according to claim 18, wherein, When separating the data obtained from the deceleration assessment of the test vehicle into the plurality of constant speed segments and the plurality of variable speed segments, the force applied in each of the plurality of constant speed segments and the force applied in the variable speed segment are classified according to a preset standard.

20. A non-transitory computer-readable storage medium having a program recorded thereon for performing the method according to claim 15.

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