GB/T 29307-2022Reliability test methods of drive motor system for electric vehicles (English PDF)

Foreword

This Document was drafted as per the rules specified in GB/T 1.1-2020 Directives for Standardization - Part 1: Rules for the Structure and Drafting of Standardizing Documents.

This Document replaced GB/T 29307-2012 The Reliability Test Methods of Drive Motor System for Electric Vehicles. Compared with GB/T 29307-2012, the major technical changes of this Documents are as follows besides the structural adjustments and editorial modifications.

a) Modify the scope; and add the provisions for special machine models to be implemented by reference (see Clause 1 of this Edition; Clause 1 of 2012 Edition);

b) Modify the term and definition of continuous torque; delete the terms and definitions of maximum operating speed and peak power; and add the terms and definitions of rated speed and rated voltage (see Clause 3 of this Edition; Clause 3 of 2012 Edition);

c) Delete the requirements for the test power supply; and add the cooling requirements for the oil-cooled drive motor system (see Clause 4 of this Edition; Clause 4 of 2012 Edition);

d) Add the running-in requirements before the test when the drive motor system under test includes a reducer (see 5.1.3 of this Edition);

e) Modify the test items of the preliminary test and retest of performance (see 5.2 of this Edition; 5.2 of 2012 Edition);

f) Modify the reliability test specification; and the test item has been changed from one item of torque load cycle to two reliability tests of speed up and down cycle and torque load cycle (see Clause 6 of this Edition; Clause 6 of 2012 Edition);

g) Modify the reliability assessment method (see Clause 9 of this Edition; Clause 9 of 2012 Edition).

Please note some contents of this Document may involve patents. The issuing agency of this Document shall not assume the responsibility to identify these patents.

1 Scope

This Document specifies the test conditions, test procedures, test methods, inspection and maintenance, arrangement of test results, reliability evaluation and test report for bench reliability tests of drive motor systems for electric vehicles.

This Document is applicable to the drive motor system for electric vehicles, and the vehicle motor system with only auxiliary drive function or power generation function shall be implemented as a reference.

2 Normative References

The provisions in following documents become the essential provisions of this Document through reference in this Document. For the dated documents, only the versions with the dates indicated are applicable to this Document; for the undated documents, only the latest version (including all the amendments) is applicable to this Document.

GB/T 2900.13 Electrotechnical terminology - Dependability and quality of service

GB/T 18488.1 Drive motor system for electric vehicles - Part 1: Specification

GB/T 18488.2 Drive motor system for electric vehicles - Part 2: Test methods

GB/T 19596 Terminology of electric vehicles

QC/T 893 Failure Classification and Assessment of Electrical Machine System for Electric Vehicle

QC/T 1022-2015 Technical specification for reduction gearbox of battery electric passenger cars

3 Terms and Definitions

For the purposes of this Document, the terms and definitions given in GB/T 2900.13, GB/T 18488.1, GB/T 19596 and QC/T 893 apply.

4 Test Conditions

5 Test Procedures

6 Test Methods

7 Inspection and Maintenance

8 Processing of Test Result

8.1 Carry out failure records according to QC/T 893, and provide failure-related photos.

8.2 Based on the actual continuous running time (h) of the drive motor system under test and the records during the running process, carry out the evaluation according to Clause 9.

9 Reliability Assessment

9.1 The manufacturer can choose to use the mean time to first failure (MTTFF), the number of downtimes, the mean time between failures (MTBF) and the lower confidence limit (thetaL) of the mean time between failures to carry out a reliability assessment.

The mean time to first failure (MTTFF) can be calculated by Formulas (1) and (2).

9.2 After the reliability test, the performance retest of the drive motor system shall meet the following requirements.

--- Abnormal noise and bearing stagnation shall not occur during operation;

--- The insulation resistance value shall meet the relevant provisions of GB/T 18488.1;

--- Compared with the preliminary test of performance, the peak torque attenuation at rated speed and maximum operating speed shall be no greater than 5%.

10 Test Report

The test report shall at least include the following.

a) foreword. explain the source of the test task;

b) test basis;

c) the purpose of the test;

d) test object. indicate the main parameters of the drive motor system under test, and attach graphics, photos and necessary descriptions;

e) test equipment and instruments. the name, manufacturer, model, accuracy and other basic parameters of the main equipment and instruments, as well as the effective date of calibration and the measurement position shall be stated;

f) differences between test conditions and standards; g) test results.

1) sorting out the original data should be represented by a curve, and important data can be listed;

2) calculation results of reliability evaluation indicators;

3) failure and maintenance statistics;

4) adjustment and replacement records during the test;

5) performance test results.

h) conclusions and recommendations.

1) describe the mode, type and number of failures;

2) describe the mean time to first failure, the number of failure shutdowns and the mean time between failures;

3) when necessary, according to the reliability test results, put forward suggestions for improvement and supplementary tests. i) test date.

Appendix A (Informative) Recommended Principles for Reliability Test Cycle Times

A.1 The number of test cycles for speed up and down cycles and torque load cycles should be selected according to the design life of the drive motor system, as shown in Table A.1.

Design life Levels Levels-1 million km and above A Level-600 thousand km B Level-300 thousand km C

A.2 The number of test samples for the speed up and down cycle and the torque load cycle is 1 set, respectively. If there are more specific requirements for the number of test samples, the number of test cycles can be converted according to the relevant methods in Appendix B of GB/T 28046.1-2011.

A.3 If the use conditions or configuration of the product are special, the manufacturer can also select the number of cycles of the corresponding severity level for the test according to the specific use conditions of the product or the agreement with the user. […]