Driving shaft loss compensation method and system in efficiency test

Abstract

The invention relates to a drive shaft loss compensation method in an efficiency test, and the method comprises the following steps: obtaining an installation deflection angle of a drive shaft before the efficiency test of an electric drive product is started, carrying out the efficiency test of the electric drive product based on a preset test point sequence, and obtaining test data in the test process, the test data comprises electric power data of the electric drive product, mechanical power data of the dynamometer, torque data of the dynamometer and rotating speed data of the dynamometer; determining a first rotating speed data set and a first torque data set of a driving shaft loss test based on the test point sequence of the efficiency test; and carrying out loss test on the driving shaft based on the acquired installation deflection angle. According to the efficiency test compensation method and system, the installation deflection angle of the drive shaft is accurately measured, and the torque loss equation of the drive shaft is obtained based on the deflection angle, so that the efficiency test result of an electric drive product is closer to a real value, and the test precision and reliability are remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy vehicles, and particularly relates to a driving shaft loss compensation method and system in efficiency testing. BACKGROUND

[0002] In the era of actively responding to climate change and promoting green and low-carbon transformation, energy saving and emission reduction has become the core goal of industrial upgrading and national strategy. Among them, the innovation of automobile power system is the key breakthrough to realize the "double carbon" vision, and electric drive technology is rapidly rising as an ideal alternative to internal combustion engine and inefficient motor system. However, the full release and objective quantification of the energy saving and emission reduction potential of electric drive products highly depend on the accurate measurement and evaluation of their core performance indicator-efficiency. In order to obtain accurate electric drive product efficiency, according to GB / T 18488-2024 "Electric Drive Motor System for Electric Vehicles" 6.3.8.2.7 efficiency test section, for the case where cable loss and coupling loss need to be considered, the test results can be corrected, but the specific implementation method is not described.

[0003] In the bench efficiency test of electric drive products, due to space limitations, vibration requirements, interface incompatibility and other problems, the torque sensor is usually arranged between the driving shaft and the dynamometer, and it is difficult to directly measure the differential end torque of the electric drive product. In the efficiency test of any electric drive product containing driving shaft transmission torque such as electric drive assembly and electric drive reducer, the driving shaft is a necessary test accessory 13, and itself has mechanical losses such as bearing friction, spline loss, wind resistance, and increases with the increase of driving shaft installation angle (the angle between the middle shaft axis of the driving shaft and the axis of the test piece or the dynamometer, hereinafter referred to as the driving shaft installation angle or installation angle). This part of the loss is included in the total efficiency of the test piece, resulting in a test result lower than the true efficiency of the test piece, affecting the performance evaluation, energy efficiency certification and research and development iteration accuracy of electric drive products.

[0004] The accompanying test piece 13 of the electric drive product efficiency test includes a test cable and a drive shaft. In terms of loss compensation of the accompanying test piece 13, the patent CN112345848B “Electric drive system efficiency test compensation method and electric drive system efficiency test system” provides a compensation method based on the electric power loss of the test cable, which causes the electric drive product efficiency test result to be low, but it does not solve the problem of the electric drive product efficiency test result being low caused by the mechanical loss of the drive shaft. The patent CN119165238A “Electric drive assembly efficiency test method” provides an electric drive assembly efficiency test method for obtaining the friction loss of the test bench itself, and obtaining the drag torque of the test sample when the test sample is loaded onto the test bench under non-working conditions. The drag torque includes the common contribution of the drive shaft and the test piece and only considers the influence of the rotational speed. The drag torque of the test piece is a real loss existing in the system and belongs to the efficiency component of the test piece, which should not be compensated. This method also cannot solve the problem of the electric drive product efficiency test result being low caused by the mechanical loss of the drive shaft. The drive shaft loss changes nonlinearly with the input rotational speed, input torque and installation angle of the drive shaft. This part of the error is uncontrollable. The traditional method does not consider this loss or uses a fixed coefficient to correct the error, which has a large error and affects the accuracy of the electric drive product efficiency performance evaluation. SUMMARY

[0005] The present application provides an efficiency test compensation method and system, which solves the problem of low electric drive product efficiency test result caused by drive shaft loss, accurately restores the real efficiency of the test piece, and improves the accuracy of electric drive product efficiency test.

[0006] In a first aspect, the embodiments of the present application provide a drive shaft loss compensation method in an efficiency test, which includes the following steps: An installation angle of the drive shaft before the electric drive product efficiency test is obtained. The efficiency test of the electric drive product is performed based on a preset test point sequence. Test data in the test process is obtained, which includes electric power data of the electric drive product, mechanical power data of the dynamometer, torque data of the dynamometer, and rotational speed data of the dynamometer; A first rotational speed data set and a first torque data set of the drive shaft loss test are determined based on the test point sequence of the efficiency test; The loss test of the drive shaft is performed based on the obtained installation angle. The loss test includes inputting the first rotational speed data set and the first torque data set to obtain the corresponding output rotational speed data set and output torque data set, and obtaining the torque loss equation of the drive shaft based on the input first rotational speed data set, first torque data set, output rotational speed data set and output torque data set; The compensated electric drive product efficiency is calculated based on the electric power data and the mechanical power data of the dynamometer obtained in the electric drive product efficiency test, and the torque loss equation of the drive shaft obtained in the loss test.

[0007] With reference to the first aspect, in an embodiment, the installation angle of the drive shaft is an angle between a middle shaft axis of the drive shaft and an axis of the electrically driven product or the dynamometer.

[0008] With reference to the first aspect, in an embodiment, the torque loss equation includes an equation with the input first speed data set and the first torque data set as variables and an equation with the output speed data set and the output torque data set as variables.

[0009] With reference to the first aspect, in an embodiment, the equation with the first speed data set and the first torque data set as variables is characterized by the following formula: ; Wherein, is the input first speed data set, is the input first torque data set, is a fixed loss when the input first speed data and the first torque data are 0; is a viscous friction coefficient, is a bearing friction coefficient, is a coupling loss coefficient, is a wind resistance loss coefficient, is a material deformation loss coefficient.

[0010] With reference to the first aspect, in an embodiment, the equation with the output speed data set and the output torque data set as variables is characterized by the following formula: ; Wherein, is the output speed data set, is the output torque data set, is a fixed loss when the output speed data and the output torque data are 0; is a viscous friction coefficient, is a bearing friction coefficient, is a coupling loss coefficient, is a wind resistance loss coefficient, is a material deformation loss coefficient.

[0011] With reference to the first aspect, in an embodiment, the compensated electrically driven product efficiency is obtained based on the obtained electric power data of the electrically driven product, the mechanical power data of the dynamometer, and the torque loss equation of the drive shaft, and specifically includes: The compensated electrically driven product efficiency is obtained by the following formula: ; wherein, is the mechanical power of the i-th dynamometer, is the rotational speed data of the i-th dynamometer, is the torque loss data of the i-th drive shaft under the rotational speed data and the torque data detected by the i-th dynamometer, is the electrical power data input by the electric drive product, and k is the number of drive shafts; Compensated power generation efficiency is obtained by the following formula: ; wherein, is the mechanical power of the i-th dynamometer, is the rotational speed data of the i-th dynamometer, is the torque loss data of the i-th drive shaft under the rotational speed data and the torque data detected by the i-th dynamometer, is the electrical power data output by the electric drive product, and k is the number of drive shafts.

[0012] In a second aspect, an embodiment of the present application provides a system based on the above-mentioned drive shaft loss compensation method in efficiency testing, comprising: a data acquisition module, configured to acquire an installation angle of a drive shaft before efficiency testing of an electric drive product starts and test data in a test process; a processing module, configured to determine a first rotational speed data set and a first torque data set of drive shaft loss testing based on a preset test point sequence, and based on the input first rotational speed data set and the first torque data set to obtain a corresponding output rotational speed data set and an output torque data set, and based on the input first rotational speed data set, the first torque data set, the output rotational speed data set and the output torque data set to obtain a torque loss equation of the drive shaft; a calculation module, configured to calculate a compensated electric drive product efficiency.

[0013] In combination with the second aspect, in an implementation manner, the system further comprises: a result output module, configured to output the compensated electric drive product efficiency, wherein the electric drive product efficiency comprises an electric efficiency and a power generation efficiency.

[0014] In a third aspect, an embodiment of the present application provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to execute the above-mentioned drive shaft loss compensation method in efficiency testing.

[0015] In a fourth aspect, an embodiment of the present application provides a non-transitory computer readable storage medium, wherein the non-transitory computer readable storage medium stores computer instructions, and the computer instructions cause the computer to execute the steps of the above-mentioned drive shaft loss compensation method in efficiency testing.

[0016] The technical scheme provided by the embodiments of the present application has the beneficial effects of: 1、The efficiency test compensation method and system can more accurately compensate the mechanical loss of the drive shaft by accurately measuring the installation angle of the drive shaft and obtaining the torque loss equation of the drive shaft based on the angle, which makes the efficiency test result of the electric drive product closer to the true value, solves the problem of low efficiency test result of the electric drive product caused by the loss of the drive shaft, significantly improves the accuracy and reliability of the test, and provides a more scientific and accurate basis for performance evaluation and energy efficiency certification of the electric drive product.

[0017] 2、The efficiency test compensation method and system are suitable for various electric drive products, including electric drive assemblies and electric drive reducers and any electric drive product efficiency test scene containing drive shaft torque transmission, and such flexibility enables the present application to be used in a wide range of industrial applications, improving its practical application value. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 The flowchart of the compensation method of the present application; Figure 2 The schematic diagram of the efficiency test device of the embodiment of the present application; Figure 3 The drive shaft loss test device of the embodiment of the present application.

[0020] In the figure: 1, first dynamometer; 2, second dynamometer; 3, electric drive assembly; 4, first drive shaft; 5, second drive shaft; 6, battery simulator; 7, power analyzer; 8, first torque sensor; 9, third dynamometer; 10, fourth dynamometer; 11, second torque sensor; 12, third torque sensor. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0022] The embodiment of the present application takes the efficiency test of the electric drive assembly as an example. Specifically, the electric drive assembly needs to be installed on the efficiency test device during the efficiency test, as shown in Figure 2 The efficiency test device comprises: a battery simulator 6, which is configured to simulate the working state of the power battery and provide power interaction for the electric drive assembly 3; a first dynamometer 1 and a second dynamometer 2, which are configured to simulate the wheel load and measure the rotation speed data of the dynamometers; a first drive shaft 4 and a second drive shaft 5, which are respectively arranged at the output ends of the first dynamometer 1 and the second dynamometer 2, the other end of the first drive shaft 4 is connected to the input end of the electric drive assembly 3, and the other end of the second drive shaft 5 is connected to the output end of the electric drive assembly 3, the first drive shaft 4 and the second drive shaft 5 are configured to transmit torque, and specifically comprise an intermediate shaft 401 / 501 and a ball cage 402 / 502; a first torque sensor 8, which is configured to measure the torque data at the end of the first dynamometer 1 and the torque data at the end of the second dynamometer 2; a power analyzer 7, which is configured to accurately measure the electric power data input and output by the electric drive assembly 3, and also calculate the mechanical power of the first dynamometer 1 and the second dynamometer 2 according to the input torque data and the rotation speed data; Please refer to Figure 3 The embodiment also provides a drive shaft loss test device, which comprises: a third dynamometer 9, which is configured to control the input torque data during the loss test and obtain the input rotation speed data; a fourth dynamometer 10, which is configured to control the load during the loss test and obtain the output torque data and the output rotation speed data based on the input torque data and the input rotation speed data of the third dynamometer 9; a second torque sensor 11, which is configured to measure the input torque data of the third dynamometer 9; a third torque sensor 12, which is configured to measure the output torque data of the fourth dynamometer 10.

[0023] Based on the above-mentioned efficiency test device and drive shaft loss test device, the embodiment provides a drive shaft loss compensation method in the efficiency test, which comprises the following steps: S1, obtaining the installation angle of the drive shaft before the efficiency test of the electric drive product starts, performing the efficiency test of the electric drive product based on a preset test point sequence, and obtaining test data in the test process, wherein the test data comprises electric power data of the electric drive product, mechanical power data of the dynamometer, torque data of the dynamometer, and rotation speed data of the dynamometer; Specifically, after the electric drive assembly 3 is installed on the efficiency test device, the installation deviation angles of the first drive shaft 4 and the second drive shaft 5 are measured and recorded respectively by using high-precision three-dimensional measuring equipment; The installation deviation angle of the first drive shaft 4 is the included angle between the intermediate shaft axis of the first drive shaft 4 and the axis of the electric drive assembly 3 or the first dynamometer 1. The installation deviation angle of the second drive shaft 5 is the included angle between the intermediate shaft axis of the second drive shaft 5 and the axis of the electric drive assembly 3 or the second dynamometer 2. Based on the test data obtained in the test process: The electric power data includes input electric power data and output electric power data, which are obtained by the power analyzer 7. The mechanical power data includes the mechanical power of the first dynamometer 1 and the mechanical power of the second dynamometer 2, which are obtained by the power analyzer 7. The torque data of the dynamometer includes the torque data of the first dynamometer 1 and the torque data of the second dynamometer 2, which are obtained by the first torque sensor 8. The speed data of the dynamometer includes the speed data of the first dynamometer 1 and the speed data of the second dynamometer 2, which are obtained by the speed sensors in the first dynamometer 1 and the second dynamometer 2 respectively.

[0024] In addition, during the efficiency test of the electric drive assembly 3, based on the selection of the preset test point sequence, referring to GB / T 18488-2024 “Electric Drive Motor System for Electric Vehicles” 6.3.8.1 chapter and engineering practice, the input speed points can be selected at 500 rpm, 1000 rpm, 1500 rpm……(maximum working speed); the input torque points can be selected at 5 Nm, 10 Nm, 15 Nm,……(peak torque).

[0025] S2, determining a first speed data set and a first torque data set for the drive shaft loss test based on the test point sequence of the efficiency test; Specifically, based on the test point sequence determined in step S1, in order to ensure that the loss test points of the first drive shaft 4 and the second drive shaft 5 are as close as possible to the efficiency test points of the electric drive assembly 3, it is assumed that the speed ratio of the reducer in the electric drive assembly 3 is According to the conversion relationship from the input end to the output end of the electric drive assembly 3, the first speed data set can be set as , , … The first torque data set can be set as , , … .

[0026] S3, based on the installation bias angle obtained, a loss test of the drive shaft is performed, the loss test comprising inputting a first rotating speed data set and a first torque data set to obtain a corresponding output rotating speed data set and an output torque data set, obtaining a torque loss equation of the drive shaft based on the input first rotating speed data set, the first torque data set, the output rotating speed data set and the output torque data set; Specifically: the first drive shaft 4 and the second drive shaft 5 after the efficiency test are dismounted and installed on the loss test device, the installation bias angle of the first drive shaft 4 and the second drive shaft 5 is consistent with the installation bias angle in the step S1, based on the first rotating speed data set and the first torque data set obtained in the step S2 , the third dynamometer 9 is controlled to input the first torque data set , at the same time, the input rotating speed data is obtained through the rotating speed sensor inside the third dynamometer 9, the fourth dynamometer 10 is controlled to load, to ensure that the input rotating speed data of the third dynamometer 9 meets the first rotating speed data set determined in the step S2 , and the output torque data set is obtained through the second torque sensor 11 , and the output rotating speed data set is obtained through the rotating speed sensor inside the fourth dynamometer 10 ; ; The torque loss of the first drive shaft 4 is calculated , regression analysis is performed through data statistical analysis software such as Minitab, and the torque loss equation of the first drive shaft 4 is obtained by using and as variables, and the torque loss equation of the first drive shaft 4 is obtained by using and as variables; ①The torque loss equation of the first drive shaft 4 is obtained by using and as variables, and the torque loss equation of the first drive shaft 4 is obtained by using ; Wherein, is a fixed loss when the input first rotating speed data and the first torque data are 0; is a viscous friction coefficient, is a bearing friction coefficient, is a coupling loss coefficient, is a wind resistance loss coefficient, is a material deformation loss coefficient; ②The torque loss equation of the first drive shaft 4 is obtained by using and as variables, and the torque loss equation of the first drive shaft 4 is obtained by using ; wherein, is the fixed loss when the output speed data and the output torque data are 0; is the viscous friction coefficient, is the bearing friction coefficient, is the coupling loss coefficient, is the wind resistance loss coefficient, is the material deformation loss coefficient.

[0027] In addition, in order to ensure that the obtained torque loss equation of the first drive shaft 4 has high accuracy and generalization ability, the following evaluations need to be performed. If the following conditions are not met, the abnormal values or insignificant variables need to be removed according to the principles of mathematical statistics until the following conditions are met: 1. Adjust > 0.95; 2. Regression equation F test is significant (p < 0.05); 3. All regression coefficients t test is significant (p < 0.05); 4. The residual plot is roughly randomly distributed and cannot appear U-shaped or horn-shaped distribution; 5. VIF is less than 2, and there is no multicollinearity.

[0028] ③Similarly, the torque loss equation of the second drive shaft 5 is obtained and .

[0029] S4, based on the electric power data obtained by the electric drive product efficiency test and the mechanical power data of the dynamometer, as well as the torque loss equation of the drive shaft obtained by the loss test, the compensated electric drive product efficiency is calculated.

[0030] ①The compensated electric efficiency of the electric drive assembly 3 is obtained by the following formula: ; wherein, is the mechanical power of the first dynamometer 1, is the mechanical power of the second dynamometer 2, is the speed data detected by the first dynamometer 1, is the torque loss data of the first drive shaft 4 under the condition that the speed data detected by the first dynamometer 1 is and the torque data detected by the first torque sensor 8 is , is the speed data detected by the second dynamometer 2, is the torque loss data of the second drive shaft 5 under the condition that the speed data detected by the second dynamometer 2 is and the torque data detected by the first torque sensor 8 is , 9.55 is the electric power data input to the electric drive assembly 3; it is a conversion factor used to convert torque and speed into power. ② Power generation efficiency of electric drive assembly 3 after compensation Obtain it using the following formula: ; in, The mechanical power of the first dynamometer 1 The mechanical power of the second dynamometer 2 The rotational speed data detected by the first dynamometer 1. The rotational speed data of the first drive shaft 4 detected by the first dynamometer 1 is as follows: The input torque detected by the first torque sensor 8 is Torque loss data below, The rotational speed data detected by the second dynamometer 2. The rotational speed data detected by the second dynamometer 2 is The output torque detected by the first torque sensor 8 is Torque loss data below, This is the electric power output data of the electric drive assembly 3. 9.55 is the conversion factor used to convert torque and speed into power.

[0031] Based on the same technical concept as the above embodiments, this embodiment also provides a system for a drive shaft loss compensation method in efficiency testing, comprising: Data acquisition module: It is used to acquire the installation angle of the first drive shaft 4 and the second drive shaft 5 before the start of the efficiency test of electric drive assembly 3 and the test data during the efficiency test of electric drive assembly 3; Specifically, it measures the installation angle of the first drive shaft 4 and the second drive shaft 5 using high-precision three-dimensional measuring equipment (such as FARO); The electrical power data in the test data includes input electric power data and output electric power data, which are obtained through power analyzer 7; The mechanical power data based on the test data includes the mechanical power of the first dynamometer 1 and the mechanical power of the second dynamometer 2, which is obtained through the power analyzer 7. The torque data from the dynamometers in the test data includes the torque data of the first dynamometer 1 and the torque data of the second dynamometer 2, which are acquired through the first torque sensor 8. The speed data of the dynamometers in the test data includes the speed data of the first dynamometer 1 and the speed data of the second dynamometer 2, which are obtained by the speed sensors in the first dynamometer 1 and the second dynamometer 2, respectively. a processing module configured to determine a first rotation speed data set of the first drive shaft 4 and the second drive shaft 5 during the loss test based on a test point sequence of the electric drive assembly 3 efficiency test and a first torque data set , and based on the input and to obtain a corresponding output rotation speed data set and an output torque data set , and based on the input , , and to obtain a torque loss equation of the drive shaft; wherein the torque loss equation comprises an equation obtained using and as variables and an equation obtained using and as variables.

[0032] a calculation module configured to calculate a compensated electric drive assembly 3 efficiency; wherein the compensated electric drive assembly 3 efficiency comprises a compensated power generation efficiency and a compensated motoring efficiency.

[0033] a result output module configured to output the compensated power generation efficiency and the compensated motoring efficiency of the electric drive assembly 3.

[0034] In addition, the embodiment further provides an electronic device including a memory and a processor, the memory stores a computer program, and the processor implements the efficiency test drive shaft loss compensation method in the above embodiment when executing the computer program.

[0035] The memory can be a hard disk, a solid state disk, a flash memory or other non-transitory storage medium, used to store the computer program, test data, installation bias angle, torque loss equation and the like for implementing the efficiency test drive shaft loss compensation method; The processor can be a central processing unit (CPU), a graphics processing unit (GPU) or other programmable logic device, used to perform data acquisition, processing, calculation and result output and the like, and the processor implements the following steps when executing the computer program: data acquisition: acquiring the installation bias angle of the first drive shaft 4 and the second drive shaft 5 before the electric drive assembly 3 efficiency test starts and the test data during the electric drive assembly 3 efficiency test through the data acquisition module.

[0036] processing: determining a first rotation speed data set of the first drive shaft 4 and the second drive shaft 5 during the loss test based on a test point sequence of the electric drive assembly 3 efficiency test and a first torque data set , based on the installation bias angle of the efficiency test, the third dynamometer 9 inputs the first torque data set through the processing module At the same time, the input speed data is obtained through the speed sensor inside the third dynamometer 9, and the fourth dynamometer 10 is controlled to load to ensure that the input speed data of the third dynamometer 9 meets the first speed data set , and the output torque data set is obtained through the second torque sensor 11 , and the output speed data set is obtained through the speed sensor inside the fourth dynamometer 10 , and based on these data, the torque loss equation of the first drive shaft 4 and the second drive shaft 5 is obtained.

[0037] Calculation: Calculate the power generation efficiency and motor efficiency of the compensated electric drive assembly 3 through the calculation module.

[0038] Result output: Output the power generation efficiency and motor efficiency of the compensated electric drive assembly 3 through the result output module.

[0039] A non-transitory computer readable storage medium stores computer instructions, which make the computer execute the steps of the drive shaft loss compensation method in the efficiency test in one of the above embodiments; The storage medium can be a hard disk, a solid state disk, a flash memory, an optical disk or other non-transitory storage medium, used to store a computer program for implementing the drive shaft loss compensation method in the efficiency test, test data, installation bias angle, torque loss equation, etc. The computer instructions include specific code implementation of data acquisition, processing, calculation and result output operations, and these instructions can realize the above test functions when executed by the processor.

[0040] In the description of the present application, it should be explained that the positions or position relationships indicated by the terms "upper", "lower" and the like are based on the positions or position relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and are not indicative or imply that the indicated devices or elements must have a particular position, be constructed and operated in a particular position, and therefore cannot be understood as a limitation on the present application. Unless otherwise specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0041] It should be noted that, in the present application, the relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another, without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0042] The foregoing is merely illustrative of the principles of the application and various modifications can be made by those skilled in the art without departing from the spirit and scope of the application. The above embodiments are illustrative, and not restrictive, of the scope of the application.

Claims

1. A method of drive shaft loss compensation in efficiency testing, characterized by, The method comprises the following steps: obtaining the installation angle of the drive shaft before the efficiency test of the electric drive product starts, performing the efficiency test of the electric drive product based on a preset test point sequence, obtaining test data in the test process, the test data comprising electric power data of the electric drive product, mechanical power data of the dynamometer, torque data of the dynamometer, and rotational speed data of the dynamometer; determining a first rotational speed data set and a first torque data set for the drive shaft loss test based on the test point sequence of the efficiency test; performing the loss test of the drive shaft based on the obtained installation angle, the loss test comprising inputting the first rotational speed data set and the first torque data set to obtain a corresponding output rotational speed data set and an output torque data set, and obtaining a torque loss equation of the drive shaft based on the input first rotational speed data set, the first torque data set, the output rotational speed data set, and the output torque data set; calculating the compensated electric drive product efficiency based on the electric power data and the mechanical power data of the dynamometer obtained in the efficiency test of the electric drive product and the torque loss equation of the drive shaft obtained in the loss test.

2. The method of claim 1, wherein, The installation angle of the drive shaft is the included angle between the intermediate shaft axis of the drive shaft and the axis of the electric drive product or the axis of the dynamometer.

3. The method of claim 1, wherein, The torque loss equation comprises an equation with the input first rotational speed data set and the first torque data set as variables and an equation with the output rotational speed data set and the output torque data set as variables.

4. The method of claim 3, wherein, The equation with the first rotational speed data set and the first torque data set as variables is represented by the following formula: ； wherein, is a first set of rotational speed data, is a first set of torque data, is a fixed loss when the first rotational speed data and the first torque data are 0; is a viscous friction coefficient, is a bearing friction coefficient, is a coupling loss coefficient, is a windage loss coefficient, is a material deformation loss coefficient.

5. The method of claim 3, wherein, The equation with the output rotational speed data set and the output torque data set as variables is represented by the following formula: ； wherein, is a set of output speed data, is a set of output torque data, is a fixed loss when the output speed data and the output torque data are 0; is a viscous friction coefficient, is a bearing friction coefficient, is a coupling loss coefficient, is a windage loss coefficient, is a material deformation loss coefficient.

6. The method of claim 1, wherein, The compensated electric drive product efficiency is obtained based on the electric power data of the electric drive product, the mechanical power data of the dynamometer, and the torque loss equation of the drive shaft, and specifically comprises: Compensated electric efficiency Obtained by the following equation: ； wherein, is the mechanical power of the ith dynamometer, is the rotational speed data of the ith dynamometer, is the torque loss data of the ith drive shaft under the rotational speed data and the torque data detected by the ith dynamometer, is the electrical power data input by the electric drive product, k is the number of drive shafts; Compensated power generation efficiency Obtained by the following equation: ； wherein, is the mechanical power of the i-th dynamometer, is the rotational speed data of the i-th dynamometer, is the torque loss data of the i-th drive shaft at the rotational speed data and the torque data detected by the i-th dynamometer, is the electrical power data output by the electric drive product, k is the number of drive shafts.

7. A system based on the method of drive shaft loss compensation in efficiency test of claim 1, characterized by, comprises: a data acquisition module for obtaining the installation angle of the drive shaft before the efficiency test of the electric drive product starts and test data in the test process; a processing module for determining a first rotational speed data set and a first torque data set for the drive shaft loss test based on a preset test point sequence, and obtaining a corresponding output rotational speed data set and an output torque data set based on the input first rotational speed data set and the first torque data set, and obtaining a torque loss equation of the drive shaft based on the input first rotational speed data set, the first torque data set, the output rotational speed data set, and the output torque data set; a calculation module for calculating the compensated electric drive product efficiency.

8. The system for drive shaft loss compensation in efficiency test method according to claim 7, characterized in that, further comprises: a result output module for outputting the compensated electric drive product efficiency, the electric drive product efficiency comprising electric motor efficiency and electric generator efficiency. 9.An electronic device comprising a memory and a processor, the memory storing a computer program, wherein, The processor executes the computer program to implement the efficiency test drive shaft loss compensation method of any one of claims 1-6.

10. A non-transitory computer-readable storage medium, comprising: The non-transitory computer readable storage medium stores computer instructions, which cause the computer to perform the steps of the efficiency test drive shaft loss compensation method of any one of claims 1-6.

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