New energy automobile motor temperature cycle test method

Abstract

The invention belongs to the technical field of motor temperature cycle tests, and particularly relates to a new energy automobile motor temperature cycle test method. The test driving motor is placed in a low-temperature box, and the temperature is set to be TA; the time for keeping the temperature in the low-temperature box at TA is t1, the test driving motor is transferred from the low-temperature box to the high-temperature box, and the transfer time is t2; setting the temperature in the high-temperature box as TB, keeping the temperature in the high-temperature box at the high-temperature TB for a specified time t3, transferring the test driving motor from the high-temperature box to the low-temperature box, and repeating the next cycle; according to the invention, the rapid change condition of the environment temperature in the use process of a user can be simulated, the high and low temperature keeping time, the temperature conversion time and the cycle index are stipulated, the failure mode of the electric drive system is verified, and the reliability of the electric drive system is effectively detected.

Description

Technical Field

[0001] The invention belongs to the technical field of motor temperature cycle testing, and specifically relates to a new energy vehicle motor temperature cycle testing method. Background Art

[0002] With the rapid development of electric vehicles, the reliability of electric drive systems is of vital importance. Electric drive systems will face various temperature environments in actual work, and temperature changes may have a significant impact on the performance and life of the electric drive system. Therefore, an effective electric drive temperature cycle test method and device are needed to simulate the temperature changes in actual work to detect the reliability of the electric drive system.

[0003] At present, in the existing standards related to motor temperature cycle tests, only some temperature cycle test methods at the principle level are explained, and there is not much description of the specific test methods, which cannot support specific test work. Summary of the invention

[0004] In order to overcome the above problems, the present invention provides a temperature cycle test method for new energy vehicle motors; it can simulate the rapid changes in ambient temperature during user use, stipulate the time for maintaining high and low temperatures, the time for temperature conversion and the number of cycles, verify the failure mode of the electric drive system, and effectively detect the reliability of the electric drive system.

[0005] A temperature cycle test method for a new energy vehicle motor includes the following contents:

[0006] Step 1: Place the test drive motor in a low temperature box and set the temperature in the low temperature box to TA;

[0007] Step 2: The temperature in the low temperature box is maintained at TA for a specified time t1, where t1 includes the time required for the temperature in the low temperature box to drop to TA after the test drive motor is placed therein;

[0008] Step 3: Transfer the test drive motor from the low temperature box to the high temperature box. The transfer time t2 includes the time taken to take the test drive motor out of the low temperature box and the time taken to put the test drive motor into the high temperature box, as well as the time the test drive motor stays at the ambient temperature of the test room during the process of taking out and putting in.

[0009] Step 4, setting the temperature in the high temperature box to TB, and maintaining the temperature in the high temperature box at high temperature TB for a specified time t3, where the t3 value includes the time required for the temperature in the high temperature box to rise to TB after the test drive motor is placed;

[0010] Step 5, transfer the test drive motor from the high temperature box to the low temperature box, and repeat steps 1 to 5 to proceed to the next cycle.

[0011] Step six: Complete all test cycles as required.

[0012] The time t1 in step 2 is calculated from the moment the test drive motor is placed in the test box.

[0013] The time required for the temperature in the low temperature box to drop to TA after the test drive motor is placed in the step 2 is no more than 0.1*t1.

[0014] The conversion time t2 in step 3 is: <10s.

[0015] The selection of the switching time t2 in step 3 depends on the thermal time constant of the test drive motor and the most rapid temperature change condition it experiences during use.

[0016] The duration t3 in step 4 is calculated from the moment the test drive motor is placed in the high temperature box.

[0017] After the test drive motor is placed in step 4, the time required for the temperature in the high temperature box to rise to TB is no more than 0.1t3.

[0018] The test environment is set as follows: the temperature is set at 18° C. to 28° C., the relative humidity is set at 5% to 75%, and the air pressure is set at 86Kpa to 106Kpa.

[0019] The TA is -40°C, t1 is 3h, t2 is 30s, TB is 85°C, and t3 is 3h.

[0020] The test in step 6 is repeated 100 times, and all the tests are completed.

[0021] Beneficial effects of the present invention:

[0022] The present invention can simulate the rapid changes in ambient temperature during user use, perform temperature change tests with a faster temperature change rate and a wider temperature change range, verify material cracking or sealing failure caused by aging and different temperature expansion coefficients of the electric drive system, and effectively detect the reliability of the electric drive system; and when a test chamber is used for testing, the temperature cycle range, change rate and number of cycles can be adjusted according to different test requirements, which has high flexibility, greatly improves convenience, reduces resource requirements, shortens the test cycle, and improves test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings used in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without creative work.

[0024] Figure 1 It is a schematic diagram of the test temperature and time of the present invention. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0026] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0028] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0029] Example 1

[0030] A temperature cycle test method for a new energy vehicle motor includes the following contents:

[0031] Step 1: Place the test drive motor in a low temperature box and set the temperature in the low temperature box to TA;

[0032] Step 2: The temperature in the low temperature box is maintained at TA for a specified time t1, where t1 includes the time required for the temperature in the low temperature box to drop to TA after the test drive motor is placed therein;

[0033] Step 3: Transfer the test drive motor from the low temperature box to the high temperature box. The transfer time t2 includes the time taken to take the test drive motor out of the low temperature box and the time taken to put the test drive motor into the high temperature box, as well as the time the test drive motor stays at the ambient temperature of the test room during the process of taking out and putting in.

[0034] Step 4, setting the temperature in the high temperature box to TB, and maintaining the temperature in the high temperature box at high temperature TB for a specified time t3, where the t3 value includes the time required for the temperature in the high temperature box to rise to TB after the test drive motor is placed;

[0035] Step 5, transfer the test drive motor from the high temperature box to the low temperature box, and repeat steps 1 to 5 to proceed to the next cycle.

[0036] Step six: Complete all test cycles as required.

[0037] The time t1 in step 2 is calculated from the moment the test drive motor is placed in the test box.

[0038] The time required for the temperature in the low temperature box to drop to TA after the test drive motor is placed in the step 2 is no more than 0.1*t1.

[0039] The conversion time t2 in step 3 is: <10s.

[0040] The selection of the switching time t2 in step 3 depends on the thermal time constant of the test drive motor and the most rapid temperature change condition it experiences during use.

[0041] The duration t3 in step 4 is calculated from the moment the test drive motor is placed in the high temperature box.

[0042] After the test drive motor is placed in step 4, the time required for the temperature in the high temperature box to rise to TB is no more than 0.1t3.

[0043] The test environment is set as follows: the temperature is set at 18° C. to 28° C., the relative humidity is set at 5% to 75%, and the air pressure is set at 86Kpa to 106Kpa.

[0044] The TA is -40°C, t1 is 3h, t2 is 30s, TB is 85°C, and t3 is 3h.

[0045] The test in step 6 is repeated 100 times, and all the tests are completed.

[0046] Example 2

[0047] Test environment settings: set the temperature, relative humidity, air pressure and altitude as required;

[0048] Temperature cycle test with specified switching time:

[0049] B1. Pre-adjust the temperature in the low-temperature box to the required low temperature TA, and then place the test drive motor into the box.

[0050] B2. The temperature of the low temperature box should be maintained at TA for a specified time t1. The t1 value includes the time required for the temperature in the box to stabilize to TA after the test drive motor is placed. This time should not be greater than 0.1t1. The duration t1 is calculated from the moment the test drive motor is placed in the test box.

[0051] B3. Then, transfer the test drive motor from the low temperature box to the high temperature box. The transfer time t2 includes the time to take it out of one box and put it into the second box, as well as the time to stay at the ambient temperature of the test room.

[0052] The conversion time should be: <10s.

[0053] The selection of the switching time t2 depends on the thermal time constant of the test drive motor and the most rapid temperature change conditions it experiences during use.

[0054] B4. The temperature of the high temperature box should be maintained at high temperature TB for a specified time t1. The t1 value includes the time required for the temperature in the box to stabilize to TB after the test drive motor is placed. This time should not be greater than 0.1t1. The duration t1 is calculated from the moment the test drive motor is placed in the test box.

[0055] B5. Then, the test drive motor is transferred from the high temperature box to the low temperature box for the next cycle. The conversion time t2 includes the time to take it out of one box and put it into the second box, as well as the time it stays at the ambient temperature of the test room.

[0056] B6. Complete all test cycles as specified in the protocol.

[0057] After completing all test cycles, evaluate and inspect the motor according to the specified requirements:

[0058] 1. Appearance evaluation

[0059] Serial number Check content Evaluation Criteria 1 Appearance defects No cracks, etc. are allowed 2 Plastic parts Deformation due to high temperature is not allowed 3 Leakage inspection No liquid leakage, etc.

[0060] 2. Performance Check

[0061] According to the test method in GB / T 18488, the performance test of the drive motor system under test is carried out.

[0062] Serial number Inspection items Evaluation Criteria 1 Peak Power Reference technical description is executed as agreed by both parties 2 Peak Torque Reference technical description is executed as agreed by both parties 3 Insulation resistance According to the agreement or GB / T 18488 4 Cooling circuit tightness According to the agreement or GB / T 18488

[0063] 3. Disassembly inspection

[0064]

[0065]

[0066] Further, in step A, the temperature is set to 18° C. to 28° C., the relative humidity is set to 5% to 75%, and the air pressure is set to 86Kpa to 106Kpa.

[0067] Further, in step B1, the test drive motor is placed in a low temperature test box, and the temperature of the test box is adjusted to -40°C.

[0068] Furthermore, in step B2, the temperature of the low temperature box should be maintained at -40°C for a prescribed time of 3 hours, including the time required for the temperature in the box to stabilize to -40°C after the test drive motor is placed in the box, which time should not be greater than 0.3 hours.

[0069] Further, in step B3, the test drive motor is transferred from the low temperature box to the high temperature box, and the conversion time is ≤30s, which includes the time of taking it out from one box and putting it into the second box, as well as the time of staying at the ambient temperature of the test room.

[0070] Furthermore, in step B4, the temperature of the high temperature box should be maintained at a high temperature of 85°C for a prescribed time of 3 hours, including the time required for the temperature in the box to stabilize to 85°C after the test drive motor is placed in the box, and this time should not be greater than 0.3 hours.

[0071] Further, in step B6, the test cycle is repeated 100 times, and all the tests are completed.

[0072] Furthermore, after the test has been carried out for the prescribed time of 3 hours, if the next transition from low temperature to high temperature or from high temperature to low temperature cannot be started immediately (such as overnight or weekend rest, etc.), the test samples can be kept in the low temperature box.

[0073] Furthermore, after all cycles are completed, the test samples should be kept under the test standard atmospheric conditions for a sufficient period of time to achieve temperature stabilization.

[0074] Example 3

[0075] The temperature cycle test method for new energy vehicle motors was applied to the temperature cycle test during the development of the Pentium E541 model motor, guiding the entire test cycle and successfully completing the test content.

[0076] 1. Test preparation

[0077] 11. Test environment settings:

[0078] Set the temperature to 18-28°C, the relative humidity to 5-75%, and the air pressure to 86Kpa-106Kpa.

[0079] 12. Test equipment requirements:

[0080] The motor temperature cycle test is carried out in a test chamber. Any area in the test chamber where the test drive motor system is placed should be able to maintain the air temperature specified in the test. The performance requirements of the test chamber are shown in the table below:

[0081]

[0082] 13. Installation or support of test drive electric drive system

[0083] Unless otherwise specified in the relevant specifications, the mounting or supporting frame shall have low thermal conductivity so that the test drive-motor system is effectively thermally isolated.

[0084] The test drive motor system shall be positioned so that air can circulate freely between the test drive motor system and the interior surfaces of the test chamber.

[0085] 2. Temperature cycle test

[0086] Place the test drive motor into a low-temperature test chamber and adjust the chamber temperature to -40°C.

[0087] The temperature of the low temperature box should be maintained at -40℃ for the specified time of 3h, including the time required for the temperature in the box to stabilize to -40℃ after the test drive motor is placed in it. This time should not be more than 0.3h.

[0088] The test drive motor is transferred from the low temperature box to the high temperature box, and the conversion time is ≤30s, which includes the time of taking it out from one box and putting it into the second box, as well as the time it stays at the ambient temperature of the test room.

[0089] The temperature of the high temperature box should be maintained at 85℃ for the specified time of 3h, including the time required for the temperature in the box to stabilize to 85℃ after the test drive motor is placed in the box. This time should not be greater than 0.3h.

[0090] The test drive motor is then transferred from the high temperature box to the low temperature box for the next cycle. The transfer time is ≤ 30s, including the time to take it out of one box and put it into the second box, as well as the time it stays at the ambient temperature of the test room.

[0091] The test cycle was repeated 100 times and all the tests were completed.

[0092] 3. Evaluation

[0093] 31. Appearance evaluation

[0094] Serial number Check content Evaluation Criteria 1 Appearance defects No cracks, etc. are allowed 2 Plastic parts Deformation due to high temperature is not allowed 3 Leakage inspection No liquid leakage, etc.

[0095] 32. Performance Check

[0096] According to the test method in GB / T 18488, the performance test of the drive motor system under test is carried out.

[0097]

[0098]

[0099] 33. Disassembly and evaluation

[0100]

[0101] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the protection scope of the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention. These simple variations all belong to the protection scope of the present invention.

[0102] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0103] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A temperature cycle test method for a new energy vehicle motor, characterized in that: It includes the following: Step 1: Place the test drive motor in a low temperature box and set the temperature in the low temperature box to TA; Step 2: The temperature in the low temperature box is maintained at TA for a specified time t1, where t1 includes the time required for the temperature in the low temperature box to drop to TA after the test drive motor is placed therein; Step 3: Transfer the test drive motor from the low temperature box to the high temperature box. The transfer time t2 includes the time taken to take the test drive motor out of the low temperature box and the time taken to put the test drive motor into the high temperature box, as well as the time the test drive motor stays at the ambient temperature of the test room during the process of taking out and putting in. Step 4, setting the temperature in the high temperature box to TB, and maintaining the temperature in the high temperature box at high temperature TB for a specified time t3, where the t3 value includes the time required for the temperature in the high temperature box to rise to TB after the test drive motor is placed; Step 5, transfer the test drive motor from the high temperature box to the low temperature box, and repeat steps 1 to 5 to proceed to the next cycle. Step six: Complete all test cycles as required.

2. A new energy vehicle motor temperature cycle test method according to claim 1, characterized in that: The time t1 in step 2 is calculated from the moment the test drive motor is placed in the test box.

3. A new energy vehicle motor temperature cycle test method according to claim 1, characterized in that: The time required for the temperature in the low temperature box to drop to TA after the test drive motor is placed in the step 2 is no more than 0.1*t1.

4. A new energy vehicle motor temperature cycle test method according to claim 1, characterized in that: The conversion time t2 in step 3 is: <10s.

5. A new energy vehicle motor temperature cycle test method according to claim 1, characterized in that: The selection of the switching time t2 in step 3 depends on the thermal time constant of the test drive motor and the most rapid temperature change condition it experiences during use.

6. A new energy vehicle motor temperature cycle test method according to claim 1, characterized in that: The duration t3 in step 4 is calculated from the moment the test drive motor is placed in the high temperature box.

7. A new energy vehicle motor temperature cycle test method according to claim 1, characterized in that: After the test drive motor is placed in step 4, the time required for the temperature in the high temperature box to rise to TB is no more than 0.1t3.

8. A new energy vehicle motor temperature cycle test method according to claim 1, characterized in that: The test environment is set as follows: the temperature is set at 18° C. to 28° C., the relative humidity is set at 5% to 75%, and the air pressure is set at 86Kpa to 106Kpa.

9. A new energy vehicle motor temperature cycle test method according to claim 1, characterized in that: The TA is -40°C, t1 is 3h, t2 is 30s, TB is 85°C, and t3 is 3h.

10. A new energy vehicle motor temperature cycle test method according to claim 1, characterized in that: The test in step 6 is repeated 100 times, and all the tests are completed.

Images