Driving motor life prediction method and device, equipment and medium

Abstract

The invention discloses a life prediction method and device of a driving motor, equipment and a medium. The method comprises the following steps: performing a high-low temperature impact durability test on the vehicle driving motor according to temperature spectrum information and a high-low temperature impact acceleration model, and determining an acceleration factor of the high-low temperature impact acceleration model; determining the failure cycle number of the high and low temperature impact durability test according to the operation condition of the vehicle and the acceleration factor, determining the total operation time of the driving motor according to the stator insulation life total damage, and finally determining the first operation time of the single cycle of the failure cycle number through the failure cycle number and the total operation time. And determining the predicted life mileage of the driving motor according to the road spectrum information and the first operation time. The high-temperature structure working condition under the service life damage model and the high-low temperature impact structure working condition under the high-low temperature impact acceleration model are combined, accurate prediction of the predicted service life mileage of the driving motor is achieved through the road spectrum information and the generated first operation time, and the accuracy of service life prediction is improved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the technical field of drive motors, and in particular to a life prediction method, device, equipment and medium for a drive motor. Background Art

[0002] The drive motor of new energy vehicles is an actuator that converts electrical energy into mechanical energy. It is widely used in pure electric vehicles, hybrid vehicles, hydrogen-powered passenger cars, commercial vehicles and construction machinery, and is an important source of power for new energy vehicles. The drive motor of new energy vehicles has the characteristics of compact layout space, complex working environment and harsh operating conditions. The research focus in this field is to ensure the long-term stable and reliable operation of the drive motor while meeting the requirements of small size, high power and high power density. The insulation failure of the drive motor stator winding is one of the main failure modes of the drive motor. After it occurs, it will cause the vehicle to alarm and lose power. Therefore, it is very necessary to make an early prediction of the life of the drive motor stator insulation system during the design stage. Summary of the invention

[0003] The present invention provides a life prediction method, device, equipment and medium for a drive motor, which combines the high-temperature structural condition under a life damage model with the high-temperature impact structural condition under a high-temperature impact acceleration model, and realizes accurate prediction of the predicted life mileage of the drive motor through road spectrum information and the generated first running time, thereby improving the accuracy of life prediction and providing technical support for the design of the drive motor insulation system.

[0004] In a first aspect, an embodiment of the present invention provides a method for predicting the life of a drive motor, comprising:

[0005] Acquire temperature spectrum information of the vehicle operating environment, perform a high and low temperature impact durability test on the vehicle according to the temperature spectrum information and a high and low temperature impact acceleration model, and determine an acceleration factor of the high and low temperature impact acceleration model;

[0006] Acquiring the operating condition of the vehicle, and determining the number of failure cycles of the high and low temperature impact durability test according to the operating condition and the acceleration factor;

[0007] Acquiring operation information of the vehicle, and determining the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period according to the operation information and a life damage model, and determining the total operation time of the drive motor according to the total stator insulation life damage;

[0008] Determine a first operating time of a single cycle under the number of failure cycles according to the number of failure cycles and the total operating time, obtain road spectrum information of the vehicle operation, and determine a predicted life mileage of the drive motor according to the road spectrum information and the first operating time.

[0009] Optionally, performing a high and low temperature impact durability test on the vehicle according to the temperature spectrum information and the high and low temperature impact acceleration model, and determining the acceleration factor of the high and low temperature impact acceleration model includes:

[0010] Determining an average temperature of the vehicle during operation and a difference between a maximum temperature and a minimum temperature of the vehicle during operation according to the temperature spectrum information;

[0011] The acceleration factor is determined according to an average temperature during operation of the vehicle, a difference between a maximum temperature and a minimum temperature during operation of the vehicle, and a high and low temperature shock acceleration model.

[0012] Optionally, the high and low temperature impact acceleration model includes:

[0013]

[0014] Where Acm is the acceleration factor, ΔT Test ΔT is the difference between the highest and lowest temperatures during vehicle operation. Field is the average temperature of the vehicle during operation, and C is the acceleration constant of temperature change.

[0015] Optionally, determining the number of failure cycles of the high and low temperature impact durability test according to the operating condition and the acceleration factor includes:

[0016] Determining the number of high and low temperature cycles of the vehicle according to the operating conditions and the design life of the drive motor;

[0017] The number of failure cycles is determined according to the number of high and low temperature cycles and the acceleration factor.

[0018] Optionally, the obtaining of the operation information of the vehicle and determining the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period according to the operation information and the life damage model includes:

[0019] Preprocessing the operation information to obtain the distribution of the maximum temperature of the stator winding of the drive motor over time under different drive motor cooling temperature conditions;

[0020] According to the temporal distribution of the maximum temperature of the stator winding of the drive motor under different drive motor cooling temperature conditions, the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period is calculated by the life damage model.

[0021] Optionally, determining the total operating time of the drive motor according to the total damage of the stator insulation life includes:

[0022] determining the maximum temperature of the vehicle during operation according to the temperature spectrum information;

[0023] Converting the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period into the total stator insulation life damage of a preset conversion temperature under different drive motor cooling temperatures, wherein the preset conversion temperature is the highest temperature during the operation of the vehicle;

[0024] The total operating time of the drive motor is calculated according to the design life of the drive motor and the total damage of the stator insulation life at a preset conversion temperature under different cooling temperatures of the drive motor.

[0025] Optionally, determining the predicted life mileage of the drive motor according to the road spectrum information and the first operating time includes:

[0026] Performing a failure cycle test on the drive motor to determine the actual running time of a single cycle of the drive motor;

[0027] Determining the design life mileage of the drive motor according to the road spectrum information;

[0028] And according to the ratio of the actual operating time to the first operating time and the designed life mileage, the predicted life mileage of the drive motor is determined.

[0029] In a second aspect, an embodiment of the present invention further provides a life prediction device for a drive motor, the life prediction device comprising:

[0030] A first determination module is used to obtain temperature spectrum information of the vehicle operating environment, perform a high and low temperature impact durability test on the vehicle according to the temperature spectrum information and a high and low temperature impact acceleration model, and determine an acceleration factor of the high and low temperature impact acceleration model;

[0031] A second determination module is used to obtain the operating condition of the vehicle, and determine the number of failure cycles of the high and low temperature impact durability test according to the operating condition and the acceleration factor;

[0032] a third determination module, configured to obtain operation information of the vehicle, and determine the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period according to the operation information and a life damage model, and determine the total operation time of the drive motor according to the total stator insulation life damage;

[0033] A life prediction module is used to determine a first running time of a single cycle under the number of failure cycles according to the number of failure cycles and the total running time, and to obtain road spectrum information of the vehicle operation, and to determine a predicted life mileage of the drive motor according to the road spectrum information and the first running time.

[0034] In a third aspect, an embodiment of the present invention further provides a life prediction device, the life prediction device comprising: one or more processors; a storage device for storing one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors can execute the life prediction method described in any embodiment of the present invention.

[0035] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement any life prediction method described in the embodiment of the present invention when executed.

[0036] The embodiment of the present invention obtains the temperature spectrum information of the vehicle operating environment, performs a high and low temperature impact durability test on the vehicle drive motor according to the temperature spectrum information and the high and low temperature impact acceleration model, and determines the acceleration factor of the high and low temperature impact acceleration model. The number of failure cycles of the high and low temperature impact durability test is determined according to the vehicle's operating conditions and the acceleration factor, and the total operating time of the drive motor is determined according to the total damage of the stator insulation life. Finally, the first operating time of a single cycle under the number of failure cycles is determined by the number of failure cycles and the total operating time, and the predicted life mileage of the drive motor is determined according to the road spectrum information and the first operating time. In this way, the high temperature structural condition under the life damage model is combined with the high and low temperature impact structural condition under the high and low temperature impact acceleration model to generate a new condition. Under the new condition, the first operating time of a single cycle under the number of failure cycles is determined according to the total operating time of the drive motor and the number of failure cycles of the high and low temperature impact durability test, and the predicted life mileage of the drive motor is accurately predicted by the road spectrum information and the generated first operating time, thereby improving the accuracy of life prediction. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a specific flow chart of a method for predicting the life of a drive motor provided in Embodiment 1 of the present invention;

[0038] Figure 2 is a specific flow chart of another method for predicting the life of a drive motor provided in the second embodiment of the present invention;

[0039] Figure 3 It is a structural schematic diagram of a life prediction device for a drive motor provided in Embodiment 3 of the present invention;

[0040] Figure 4 It is a structural schematic diagram of a life prediction device provided in Embodiment 4 of the present invention. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0042] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0043] Embodiment 1

[0044] Figure 1 This is a specific flow chart of a life prediction method for a drive motor provided in the first embodiment of the present invention. This embodiment can be applied to the case of predicting the service life of the drive motor insulation system. The method can be executed by the life prediction device provided in the embodiment of the present invention. The device can be implemented in software and / or hardware. The device can be configured in the life prediction device provided in the embodiment of the present invention.

[0045] S110, obtaining temperature spectrum information of the vehicle operating environment, performing a high and low temperature impact durability test on the vehicle according to the temperature spectrum information and a high and low temperature impact acceleration model, and determining an acceleration factor of the high and low temperature impact acceleration model.

[0046] The temperature spectrum information includes the temperature of the drive motor when the vehicle starts and the temperature when the vehicle is running stably. Affected by environmental factors, the temperature of the drive motor when the vehicle starts is different. For example, in summer, the temperature of the drive motor when the vehicle starts may be between 20℃-30℃, while in winter, the temperature of the drive motor when the vehicle starts may be between -40℃-0℃. The temperature when the vehicle is running stably is mainly affected by the power of the drive motor, for example, it can be 80℃. The temperature of the drive motor when the vehicle starts is quite different from the temperature when the vehicle is running stably. Under temperature alternating stress, the service life of the drive motor is affected. The high and low temperature shock acceleration model is suitable for the acceleration of high and low temperature shock experiments, which can reflect the fatigue damage under the action of temperature alternating stress, and then the high and low temperature shock durability test is carried out according to the high and low temperature shock acceleration model combined with the temperature spectrum information, and the acceleration factor of the high and low temperature shock acceleration model is determined.

[0047] S120, obtaining the operating conditions of the vehicle, and determining the number of failure cycles of the high and low temperature impact durability test according to the operating conditions and the acceleration factor.

[0048] Specifically, the operating conditions of the vehicle can be understood as the main target object and purpose of the vehicle. For example, if the main target object of the vehicle is heavy-duty traction, the purpose is short-distance transportation, it is started twice a day for round trip, and the one-way distance is 1 hour. If the design life is 15 years, the number of starts of the vehicle can be calculated based on the operating conditions and the design life. In other words, the number of high and low temperature cycles of the vehicle can be obtained. In other embodiments, the purpose of the vehicle can also be trunk logistics, then it is started six times a day, each time for 2 hours, the vehicle runs all year round, and the design life is 10 years. The number of high and low temperature cycles under the operating conditions is determined according to the operating conditions, and then the number of failure cycles after acceleration can be obtained according to the number of high and low temperature cycles and the acceleration factor. It can be understood that the number of failure cycles represents the degree of durability under high and low temperature impact.

[0049] S130, obtaining operation information of the vehicle, and determining the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period according to the operation information and the life damage model, and determining the total operation time of the drive motor according to the total stator insulation life damage.

[0050] Specifically, the vehicle's operating information is extracted from the road spectrum information collected from the actual vehicle. The operating information includes the cycle of the cyclic working condition, speed information, torque information, and the distribution ratio of the ambient temperature. Among them, the cyclic working condition is the typical cyclic working condition of the vehicle. If the motor stator insulation system installed in a commercial vehicle is taken as the object of consideration, the typical cyclic working condition can be the CHTC-HT working condition. The distribution ratio of the ambient temperature is the proportion of the vehicle under different ambient temperatures in a typical cyclic working condition period of a normally operating vehicle. The cycle time of the vehicle's cyclic working condition can be set to 1799s, and the vehicle's mileage in a cyclic working condition period is 17.33km. In addition, the collected vehicle operation information can also include the number of vehicle cycles, the proportion of different vehicle working conditions, and other information. The life of the vehicle's drive motor is predicted based on the collected vehicle operation information. On this basis, the vehicle speed information and torque information are converted into the speed torque curves of the two drive motors in the vehicle through the vehicle's transmission ratio or shifting strategy, and then the speed and torque of the drive motor are substituted into the efficiency MAP for loss calculation. The electromagnetic-thermal coupling analysis software is used to calculate the distribution of the maximum temperature of the stator winding of the motor over time under different cooling conditions. Then, based on the distribution of the maximum temperature of the stator winding of the drive motor over time under different motor cooling temperature conditions, the life damage model is used to calculate the stator insulation life damage of different drive motor stator winding temperature distribution segments under a cycle. The life damage model is:

[0051] L=Ae Ea / kT ;

[0052] Among them, L is the stator insulation life damage, A is a constant, Ea is the activation energy, for the drive motor insulation system Ea = 0.75, k is the Boltzmann constant, and T is the winding temperature. Specifically, the life damage model is the Arrhenius model, and the Boltzmann constant is 8.62E-05. The relationship between the stator insulation life and temperature of the drive motor conforms to the Arrhenius model. Through the Arrhenius model, by substituting different winding temperatures, the stator insulation life damage of different drive motor stator winding temperature distribution sections can be calculated.

[0053] In addition, based on the thermal damage accumulation law and the Arrhenius model, the accumulated insulation life damage under different temperature distributions in a working cycle can be converted to life damage at a certain temperature, that is, the stator insulation life damage of different drive motor stator winding temperature distribution segments in a cyclic working cycle is converted into the stator insulation life damage of a preset conversion temperature under different drive motor cooling temperatures, so that the total stator insulation life damage of the drive motor in a cyclic working cycle is obtained by superposition calculation, and then the total operating time of the drive motor is determined according to the design life and the calculated total stator insulation life damage of the drive motor in a cyclic working cycle.

[0054] It should be noted that the preset conversion temperature may be the maximum temperature of the vehicle in the high and low temperature shock acceleration model, that is, the maximum temperature of the vehicle during operation is determined according to the temperature spectrum information, and thus the preset conversion temperature is determined according to the maximum temperature of the vehicle during operation.

[0055] S140. Determine the first running time of a single cycle under the number of failure cycles according to the number of failure cycles and the total running time, obtain the road spectrum information of the vehicle operation, and determine the predicted life mileage of the drive motor according to the road spectrum information and the first running time.

[0056] Specifically, after the number of failure cycles is calculated by step S120 and the total running time of the drive motor is calculated by step S130, since the total running time of the drive motor calculated by step S130 is the total running time when converted to the preset conversion temperature (i.e., the highest temperature of the vehicle operation in the high and low temperature impact acceleration model), the high temperature structural condition under the life damage model can be combined with the high and low temperature impact structural condition under the high and low temperature impact acceleration model to generate a new condition, that is, the first running time of a single cycle under the number of failure cycles is determined according to the number of failure cycles of the high and low temperature impact structural condition and the total running time of the high temperature structural condition. In addition, it is also necessary to determine whether the actual running time of a single cycle of the drive motor can reach the first running time. If the actual running time of a single cycle of the drive motor is less than the first running time, it indicates that the predicted life mileage of the drive motor is less than the designed life mileage. If the actual running time of a single cycle of the drive motor exceeds the first running time, it indicates that the predicted life mileage of the drive motor exceeds the designed life mileage. In this way, the high-temperature structural condition under the life damage model is combined with the high-temperature impact structural condition under the high-temperature impact acceleration model to generate a new condition. Under the new condition, the first operating time of a single cycle under the number of failure cycles is determined according to the total operating time of the drive motor and the number of failure cycles of the high-temperature impact endurance test, and the predicted life mileage of the drive motor is accurately predicted through the road spectrum information and the generated first operating time, which improves the accuracy of life prediction and provides technical support for the design of the drive motor insulation system.

[0057] In summary, the embodiment of the present invention obtains the temperature spectrum information of the vehicle operating environment, performs a high and low temperature impact durability test on the vehicle drive motor according to the temperature spectrum information and the high and low temperature impact acceleration model, and determines the acceleration factor of the high and low temperature impact acceleration model. The number of failure cycles of the high and low temperature impact durability test is determined according to the vehicle's operating conditions and the acceleration factor, and the total operating time of the drive motor is determined according to the total damage of the stator insulation life. Finally, the first operating time of a single cycle under the number of failure cycles is determined by the number of failure cycles and the total operating time, and the predicted life mileage of the drive motor is determined according to the road spectrum information and the first operating time. In this way, the high temperature structural condition under the life damage model is combined with the high and low temperature impact structural condition under the high and low temperature impact acceleration model to generate a new condition. Under the new condition, the first operating time of a single cycle under the number of failure cycles is determined according to the total operating time of the drive motor and the number of failure cycles of the high and low temperature impact durability test, and the predicted life mileage of the drive motor is accurately predicted through the road spectrum information and the generated first operating time, thereby improving the accuracy of life prediction.

[0058] Embodiment 2

[0059] Figure 2 is a specific flow chart of another method for predicting the life of a drive motor provided by the second embodiment of the present invention. Figure 2 , the life prediction method includes:

[0060] S210. Determine the average temperature of the vehicle during operation and the difference between the highest temperature and the lowest temperature during operation of the vehicle according to the temperature spectrum information, and determine the acceleration factor according to the average temperature of the vehicle during operation, the difference between the highest temperature and the lowest temperature during operation of the vehicle, and the high and low temperature impact acceleration model.

[0061] Specifically, the high and low temperature impact acceleration model may be a Coffin-Manson acceleration model under high and low temperature impact, and the high and low temperature impact acceleration model includes:

[0062]

[0063] Where Acm is the acceleration factor, ΔT Test ΔT is the difference between the highest and lowest temperatures during vehicle operation. Fieldis the average temperature of the vehicle during operation, and C is the acceleration constant of temperature change. Then, the average temperature of the vehicle during operation and the difference between the highest temperature and the lowest temperature of the vehicle during operation are determined according to the temperature spectrum information, and the average temperature of the vehicle during operation and the difference between the highest temperature and the lowest temperature of the vehicle during operation are respectively substituted into the high and low temperature impact acceleration model to determine the acceleration factor. Among them, the value of C is related to the failure mode and can be defined by the vehicle manufacturer. For example, assuming that the average temperature of the vehicle during operation is 40°C, the highest temperature of the vehicle during operation is 80°C, and the lowest temperature of the vehicle during operation is -40°C. The acceleration factor can be calculated to be 15.59.

[0064] S220. Determine the number of high and low temperature cycles of the vehicle according to the operating conditions and the design life of the drive motor, and determine the number of failure cycles according to the number of high and low temperature cycles and the acceleration factor.

[0065] For example, if the main target of the vehicle is heavy-duty traction, the purpose is short-distance transportation, it is started twice a day, the one-way distance is 1 hour, and it runs 365 days a year. Assuming that the design life of the drive motor is 15 years, the number of high and low temperature cycles of the vehicle can be calculated to be 2*365*15=10950 times, and then the ratio of the number of high and low temperature cycles to the acceleration factor is calculated to obtain the number of failure cycles. For example, if the acceleration factor is 15.59, the number of failure cycles can be calculated to be 702 times.

[0066] It should be noted that, when determining the number of failure cycles, the embodiments of the present invention may calculate the number of failure cycles in the entire life cycle through the design life as described above, or may calculate the number of sub-failure cycles per year in units of years, and then obtain the number of failure cycles by accumulating the number of sub-failure cycles over many years. The embodiments of the present invention do not limit this, and those skilled in the art may set it as needed.

[0067] S230. Preprocess the operation information to obtain the temporal distribution of the maximum temperature of the stator winding of the drive motor under different drive motor cooling temperature conditions. According to the temporal distribution of the maximum temperature of the stator winding of the drive motor under different drive motor cooling temperature conditions, the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period is calculated by a life damage model.

[0068] Specifically, through the vehicle thermal management system, the distribution of the cooling temperature of the drive motor under different ambient temperatures can be obtained according to the distribution ratio of the ambient temperature, and the speed information and torque information of the vehicle can be converted into the speed and torque of the drive motor according to the transmission ratio of the vehicle. The maximum temperature distribution of the stator winding of the drive motor under different cooling temperature conditions of the drive motor is calculated according to the speed and torque of the drive motor. The maximum temperature distribution of the stator winding of the drive motor over time is the thermal damage of the stator winding of the drive motor under different conditions. The life damage of the drive motor is calculated by the maximum temperature distribution of the stator winding of the drive motor over time. In an optional implementation of this embodiment, the maximum temperature distribution of the stator winding of the drive motor under different cooling temperature conditions of the drive motor is calculated according to the speed and torque of the drive motor, including: substituting the speed and torque of the drive motor into the vehicle efficiency MAP for loss calculation to obtain the power loss of the drive motor at different speeds. The power loss of the drive motor at different speeds is used as the input source of the electromagnetic-thermal coupling calculation of the drive motor to obtain the maximum temperature distribution of the stator winding of the drive motor under different cooling temperature conditions of the drive motor. Then, according to the distribution of the maximum temperature of the stator winding of the drive motor over time under different drive motor cooling temperature conditions, the life damage model is used to calculate the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period.

[0069] S240. Convert the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period into the total stator insulation life damage at a preset conversion temperature at different drive motor cooling temperatures, and calculate the total operating time of the drive motor based on the design life of the drive motor and the total stator insulation life damage at a preset conversion temperature at different drive motor cooling temperatures.

[0070] Specifically, the stator insulation life damage of different drive motor stator winding temperature distribution sections under a cycle operating period is converted into the total stator insulation life damage of the preset conversion temperature under different drive motor cooling temperatures, including: respectively converting the stator insulation life damage of different drive motor stator winding temperature distribution sections into the stator insulation life under the preset conversion temperature. According to the distribution of the drive motor cooling temperature under different ambient temperatures and the distribution of the maximum temperature of the drive motor stator winding over time under different drive motor cooling temperature conditions, the stator insulation life under the preset conversion temperature is weightedly calculated to obtain the total stator insulation life damage time under the preset conversion temperature under different drive motor cooling temperatures. Among them, the preset conversion temperature can be the highest temperature of the vehicle operation in the high and low temperature impact acceleration model, that is, the highest temperature of the vehicle operation is determined according to the temperature spectrum information, so as to determine the preset conversion temperature according to the highest temperature of the vehicle operation. Specifically, the preset conversion temperature can be set to 120°C, that is, the stator insulation life damage of other different drive motor stator winding temperature distribution sections can be converted into the stator insulation life at 120°C, and the equivalent thermal damage distribution at 120°C under a working cycle can be obtained. According to the distribution of the cooling temperature of the drive motor under different ambient temperatures and the distribution of the maximum temperature of the stator winding of the drive motor over time under different drive motor cooling temperature conditions, the stator insulation life at 120°C is weightedly calculated to obtain the total stator insulation life damage at 120°C. Afterwards, the stator insulation life damage of different drive motor stator winding temperature distribution sections is converted into the stator insulation life at the preset conversion temperature through the conversion formula. The conversion formula is:

[0071]

[0072] Among them, T test is the preset conversion temperature, T field is the actual stator winding temperature of the drive motor, L test is the stator insulation life at the preset conversion temperature, L field is the stator insulation life damage at the actual stator winding temperature of the drive motor. field , preset conversion temperature T test and the actual drive motor stator winding temperature, T field Substitute it into the conversion formula to calculate the stator insulation life at the preset conversion temperature. The stator insulation life damage at the actual drive motor stator winding temperature is the life damage time, and the stator insulation life at the preset conversion temperature is the life damage time.

[0073] The total operating time of the drive motor is calculated based on the design life of the drive motor and the total damage of the stator insulation life at the preset conversion temperature under different cooling temperatures of the drive motor. For example, according to the E-level assessment, that is, at least 20,000 hours of operation at 120°C, the cooling water temperatures are set to 20°C, 30°C, 40°C, 50°C and 65°C, and the corresponding distributions of the cooling water temperatures are 0.05, 0.18, 0.32, 0.25 and 0.2, respectively. The conversion life damage of the drive motor at 120°C under different cooling water temperatures is 0.04, 0.05, 0.07, 0.10 and 0.17, respectively. Through weighted calculation, the life damage of the drive motor under a cycle operating period is 0.0924, and the total operating time of the drive motor is 20,000÷0.924≈21,645h.

[0074] S250. Determine the first running time of a single cycle under the number of failure cycles according to the number of failure cycles and the total running time, perform a failure cycle test on the drive motor to determine the actual running time of a single cycle of the drive motor, determine the design life mileage of the drive motor according to the road spectrum information, and determine the predicted life mileage of the drive motor according to the ratio of the actual running time to the first running time and the design life mileage.

[0075] Specifically, after the failure cycle number is calculated in step S120 and the theoretical total operating time of the drive motor is calculated in step S130, the first operating time of a single cycle under the failure cycle number is determined according to the failure cycle number and the total operating time, that is, the first operating time of a single cycle is the ratio of the total operating time to the failure cycle number, and then the failure cycle test is performed on the drive motor to determine the actual operating time of the single cycle of the drive motor, and the design life mileage of the drive motor is determined according to the road spectrum information of the vehicle operation, and finally the predicted life mileage of the drive motor is determined according to the ratio of the actual operating time to the first operating time and the design life mileage. For example, it is assumed that the design life mileage of the drive motor is 300w kilometers. If the ratio of the actual running time of a single cycle of the drive motor to the first running time is 80%, it indicates that the predicted life mileage of the drive motor is less than 300,000 kilometers, which should be 300×80%=240,000 kilometers. If the ratio of the actual running time of a single cycle of the drive motor to the first running time is 120%, it indicates that the predicted life mileage of the drive motor exceeds 375 kilometers, which should be 300×120%=360,000 kilometers.

[0076] In summary, the embodiment of the present invention predicts the first operating life mileage of the drive motor through a life damage model, and corrects the first operating life mileage in combination with the number of failure cycles of the high and low temperature impact acceleration model, thereby achieving accurate prediction of the predicted life mileage of the drive motor, improving the accuracy of life prediction, and providing technical support for the design of the drive motor insulation system.

[0077] Embodiment 3

[0078] Figure 3 : is a schematic diagram of the structure of a life prediction device for a drive motor provided by an embodiment of the present invention. This embodiment is applicable to the case of predicting the life of the drive motor insulation system. The specific structure of the life prediction device is as follows:

[0079] The first determination module 100 is used to obtain temperature spectrum information of the vehicle operating environment, perform a high and low temperature impact durability test on the vehicle according to the temperature spectrum information and a high and low temperature impact acceleration model, and determine an acceleration factor of the high and low temperature impact acceleration model.

[0080] The second determination module 200 is used to obtain the operating conditions of the vehicle and determine the number of failure cycles of the high and low temperature impact durability test according to the operating conditions and the acceleration factor.

[0081] The third determination module 300 is used to obtain the operating information of the vehicle, and determine the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period based on the operating information and the life damage model, and determine the total operating time of the drive motor based on the total stator insulation life damage.

[0082] The life prediction module 100 is used to determine the first running time of a single cycle under the number of failure cycles according to the number of failure cycles and the total running time, and obtain the road spectrum information of the vehicle operation, and determine the predicted life mileage of the drive motor according to the road spectrum information and the first running time.

[0083] The first determination module 100 is also used to determine the average temperature of the vehicle during operation and the difference between the highest temperature and the lowest temperature during operation of the vehicle based on the temperature spectrum information, and to determine the acceleration factor based on the average temperature of the vehicle during operation, the difference between the highest temperature and the lowest temperature during operation of the vehicle, and the high and low temperature impact acceleration model.

[0084] High and low temperature shock acceleration models include:

[0085]

[0086] Where Acm is the acceleration factor, ΔT Test ΔT is the difference between the highest and lowest temperatures during vehicle operation. Field is the average temperature of the vehicle during operation, and C is the acceleration constant of temperature change.

[0087] The second determination module 200 is further used to determine the high and low temperature cycle times of the vehicle according to the operating conditions and the design life of the drive motor, and to determine the failure cycle times according to the high and low temperature cycle times and the acceleration factor.

[0088] The third determination module 300 is also used to pre-process the operating information to obtain the temporal distribution of the maximum temperature of the stator winding of the drive motor under different drive motor cooling temperature conditions. According to the temporal distribution of the maximum temperature of the stator winding of the drive motor under different drive motor cooling temperature conditions, the total stator insulation life damage of the drive motor in different temperature distribution segments under a cyclic operating period is calculated by a life damage model.

[0089] In addition, the third determination module 300 is also used to determine the maximum temperature during vehicle operation based on the temperature spectrum information, and convert the total stator insulation life damage of the drive motor in different temperature distribution sections under a cycle of operating conditions into the total stator insulation life damage at a preset conversion temperature at different drive motor cooling temperatures, wherein the preset conversion temperature is the maximum temperature during vehicle operation. The total operating time of the drive motor is calculated based on the design life of the drive motor and the total stator insulation life damage at the preset conversion temperature at different drive motor cooling temperatures.

[0090] The life prediction module 400 is also used to perform a failure cycle test on the drive motor, determine the actual operating time of a single cycle of the drive motor, determine the design life mileage of the drive motor based on the road spectrum information, and determine the predicted life mileage of the drive motor based on the ratio of the actual operating time to the first operating time and the design life mileage.

[0091] In summary, the embodiment of the present invention obtains the temperature spectrum information of the vehicle operating environment, performs a high and low temperature impact durability test on the vehicle drive motor according to the temperature spectrum information and the high and low temperature impact acceleration model, and determines the acceleration factor of the high and low temperature impact acceleration model. The number of failure cycles of the high and low temperature impact durability test is determined according to the vehicle's operating conditions and the acceleration factor, and the total operating time of the drive motor is determined according to the total damage of the stator insulation life. Finally, the first operating time of a single cycle under the number of failure cycles is determined by the number of failure cycles and the total operating time, and the predicted life mileage of the drive motor is determined according to the road spectrum information and the first operating time. In this way, the high temperature structural condition under the life damage model is combined with the high and low temperature impact structural condition under the high and low temperature impact acceleration model to generate a new condition. Under the new condition, the first operating time of a single cycle under the number of failure cycles is determined according to the total operating time of the drive motor and the number of failure cycles of the high and low temperature impact durability test, and the predicted life mileage of the drive motor is accurately predicted through the road spectrum information and the generated first operating time, thereby improving the accuracy of life prediction.

[0092] Embodiment 4

[0093] Figure 4: is a schematic diagram of the structure of a life prediction device provided by Embodiment 4 of the present invention. The life prediction device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The life prediction device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0094] like Figure 4 As shown, the life prediction device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In RAM 13, various programs and data required for the operation of the life prediction device can also be stored. The processor 11, ROM 12 and RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0095] A number of components in the life prediction device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the life prediction device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0096] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 performs the various methods and processes described above.

[0097] In some embodiments, the life prediction device method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the life prediction device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the control method described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to execute the control method in any other appropriate manner (e.g., by means of firmware).

[0098] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0099] Embodiment 5

[0100] Embodiment 5 of the present invention further provides a storage medium including computer executable instructions. When the computer executable instructions are executed by a computer processor, they are used to execute a life prediction method for a drive motor. The life prediction method includes:

[0101] Obtain temperature spectrum information of the vehicle's operating environment, perform high and low temperature impact durability tests on the vehicle based on the temperature spectrum information and the high and low temperature impact acceleration model, and determine the acceleration factor of the high and low temperature impact acceleration model;

[0102] Obtain the operating conditions of the vehicle, and determine the number of failure cycles of the high and low temperature impact durability test based on the operating conditions and acceleration factors;

[0103] Obtaining the operation information of the vehicle, and determining the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period according to the operation information and the life damage model, and determining the first operation life mileage of the drive motor according to the total stator insulation life damage;

[0104] The predicted life mileage of the drive motor is determined based on the number of failure cycles and the first operating life mileage.

[0105] Of course, the computer executable instructions of a storage medium containing computer executable instructions provided in an embodiment of the present invention are not limited to the method operations described above, and can also execute related operations in the life prediction method of the drive motor provided in any embodiment of the present invention.

[0106] Through the above description of the implementation methods, the technicians in the relevant field can clearly understand that the present invention can be implemented by means of software and necessary general hardware, and of course it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory (FLASH), hard disk or optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0107] It is worth noting that in the embodiment of the above-mentioned search device, the various units and modules included are only divided according to functional logic, but are not limited to the above-mentioned division, as long as the corresponding functions can be achieved; in addition, the specific names of the functional units are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention.

[0108] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for predicting the life of a drive motor, characterized in that: include: Acquire temperature spectrum information of the vehicle operating environment, perform a high and low temperature impact durability test on the vehicle according to the temperature spectrum information and a high and low temperature impact acceleration model, and determine an acceleration factor of the high and low temperature impact acceleration model; Acquiring the operating condition of the vehicle, and determining the number of failure cycles of the high and low temperature impact durability test according to the operating condition and the acceleration factor; Acquiring operation information of the vehicle, and determining the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period according to the operation information and a life damage model, and determining the total operation time of the drive motor according to the total stator insulation life damage; Determine a first operating time of a single cycle under the number of failure cycles according to the number of failure cycles and the total operating time, obtain road spectrum information of the vehicle operation, and determine a predicted life mileage of the drive motor according to the road spectrum information and the first operating time.

2. The life prediction method according to claim 1, characterized in that: The step of performing a high and low temperature impact durability test on the vehicle according to the temperature spectrum information and the high and low temperature impact acceleration model, and determining the acceleration factor of the high and low temperature impact acceleration model comprises: Determining an average temperature of the vehicle during operation and a difference between a maximum temperature and a minimum temperature of the vehicle during operation according to the temperature spectrum information; The acceleration factor is determined according to an average temperature during operation of the vehicle, a difference between a maximum temperature and a minimum temperature during operation of the vehicle, and a high and low temperature shock acceleration model.

3. The life prediction method according to claim 2, characterized in that: The high and low temperature impact acceleration model includes: Where Acm is the acceleration factor, ΔT Test ΔT is the difference between the highest and lowest temperatures during vehicle operation. Field is the average temperature of the vehicle during operation, and C is the acceleration constant of temperature change.

4. The life prediction method according to claim 1, characterized in that: The determining the number of failure cycles of the high and low temperature impact durability test according to the operating conditions and the acceleration factor comprises: Determining the number of high and low temperature cycles of the vehicle according to the operating conditions and the design life of the drive motor; The number of failure cycles is determined according to the number of high and low temperature cycles and the acceleration factor.

5. The life prediction method according to claim 1, characterized in that: The obtaining of the operation information of the vehicle and determining the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period according to the operation information and the life damage model includes: Preprocessing the operation information to obtain the distribution of the maximum temperature of the stator winding of the drive motor over time under different drive motor cooling temperature conditions; According to the temporal distribution of the maximum temperature of the stator winding of the drive motor under different drive motor cooling temperature conditions, the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period is calculated by the life damage model.

6. The life prediction method according to claim 5, characterized in that: Determining the total operating time of the drive motor according to the total stator insulation life damage includes: determining the maximum temperature of the vehicle during operation according to the temperature spectrum information; Converting the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period into the total stator insulation life damage of a preset conversion temperature under different drive motor cooling temperatures, wherein the preset conversion temperature is the highest temperature during the operation of the vehicle; The total operating time of the drive motor is calculated according to the design life of the drive motor and the total damage of the stator insulation life at a preset conversion temperature under different cooling temperatures of the drive motor.

7. The life prediction method according to claim 1, characterized in that: The step of determining the predicted life mileage of the drive motor according to the road spectrum information and the first operating time includes: Performing a failure cycle test on the drive motor to determine the actual running time of a single cycle of the drive motor; Determining the design life mileage of the drive motor according to the road spectrum information; And according to the ratio of the actual operating time to the first operating time and the designed life mileage, the predicted life mileage of the drive motor is determined.

8. A life prediction device for a drive motor, characterized in that: include: A first determination module is used to obtain temperature spectrum information of the vehicle operating environment, perform a high and low temperature impact durability test on the vehicle according to the temperature spectrum information and a high and low temperature impact acceleration model, and determine an acceleration factor of the high and low temperature impact acceleration model; A second determination module is used to obtain the operating condition of the vehicle, and determine the number of failure cycles of the high and low temperature impact durability test according to the operating condition and the acceleration factor; a third determination module, configured to obtain operation information of the vehicle, and determine the total stator insulation life damage of the drive motor in different temperature distribution sections under a cyclic operating period according to the operation information and a life damage model, and determine the total operation time of the drive motor according to the total stator insulation life damage; A life prediction module is used to determine a first running time of a single cycle under the number of failure cycles according to the number of failure cycles and the total running time, and to obtain road spectrum information of the vehicle operation, and to determine a predicted life mileage of the drive motor according to the road spectrum information and the first running time.

9. A life prediction device, characterized in that: The life prediction device comprises: one or more processors; a storage device for storing one or more programs, When the one or more programs are executed by the one or more processors, the one or more processors implement the life prediction method of the drive motor as described in any one of claims 1-7.

10. A storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the life prediction method of a drive motor as described in any one of claims 1 to 7 is implemented.

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