Fault diagnosis method and system for electronic oil pump of new energy vehicle

Abstract

The invention relates to the field of fault diagnosis for electronic oil pumps, in particular to a fault diagnosis method and system for an electronic oil pump of a new energy vehicle, and the system comprises a multi-class collection module, an electronic oil pump feature extraction module, a vehicle driving feature module, a battery management feature module and a fault integral judgment module. The electronic oil pump feature extraction module extracts motor current data, pump body pressure data and temperature data, and the fault integral judgment module starts a fault integral unit to obtain and process the fault level of the current electronic oil pump according to the set fault integral level and a secondary early warning signal. The fault grade is judged through the real-time fault integral value, and fault grading early warning and intelligent processing are achieved.

Description

Technical Field

[0001] The present invention relates to the field of fault diagnosis for electronic oil pumps, and in particular to a fault diagnosis method and system for electronic oil pumps of new energy vehicles. Background Art

[0002] With the improvement of environmental protection requirements and the advancement of technology, the new energy vehicle market is expanding rapidly. Electronic oil pumps play an indispensable role in new energy vehicles. The simple threshold judgment method based on sensor data developed later, although it uses sensors such as current, pressure and temperature, is too simple to set only a single threshold to judge faults; with the use of new energy vehicles, the performance of electronic oil pumps will gradually change, and new fault modes may appear; the existing system is difficult to automatically learn and adapt to these changes, and cannot update the fault diagnosis model in time, resulting in limited ability to diagnose new faults or performance changes caused by aging. In terms of fault warning, there is a lack of effective graded warning and intelligent processing mechanisms, and it is impossible to provide drivers with appropriate response guidance according to the severity of the fault.

[0003] The present invention is proposed to address the deficiencies of the above-mentioned prior art. By designing a system that comprehensively collects the electronic oil pump's own parameters, vehicle driving data and battery management data, and using advanced feature extraction technology and fault integral judgment methods, accurate diagnosis and graded warning of electronic oil pump faults can be achieved. Summary of the invention

[0004] In order to solve the technical problems raised by the above-mentioned background technology, the present invention provides a fault diagnosis method and system for an electronic oil pump of a new energy vehicle.

[0005] The purpose of the present invention can be achieved through the following technical solutions: A first aspect of the present invention provides a fault diagnosis system for an electronic oil pump of a new energy vehicle, comprising a plurality of acquisition modules, an electronic oil pump feature extraction module, a vehicle driving feature module, a battery management feature module, a fault integral determination module, a cloud server and a database.

[0006] The multi-class acquisition module collects the electronic oil pump parameters, vehicle driving data and battery management data respectively, and sets the classified storage units to store them respectively. The specific process is as follows: The multi-type acquisition module is provided with an acquisition unit and a classification storage unit. Various types of sensors are installed on the electronic oil pump. The various types of sensors include current sensors, pump body pressure sensors and temperature sensors. The operation status of the electronic oil pump is collected in real time and integrated to obtain the parameters of the electronic oil pump. The input end of the acquisition unit is connected to the output end of the vehicle driving computer and the battery management terminal. The data information of the vehicle in the running state is collected in real time to obtain the vehicle driving data. The battery management data of the vehicle in the running state is collected in real time. The acquisition unit sends the electronic oil pump parameters, vehicle driving data and battery management data to the classification storage unit. The classification storage unit is respectively provided with an electronic oil pump storage area, a vehicle driving data storage area and a battery management data storage area, and each type of data is stored in the corresponding storage area; the output end of the multi-category acquisition module is connected to the input end of the electronic oil pump feature extraction module, the vehicle driving feature module and the battery management feature module, and the obtained data is sent to each module respectively.

[0007] The electronic oil pump feature extraction module extracts motor current data, pump body pressure data and temperature data. The specific process is as follows: D001: The output end of the electronic oil pump feature extraction module is connected to the input end of the vehicle driving feature extraction module. The electronic oil pump feature extraction module is provided with a deviation calculation unit and a first fault integration unit. The deviation calculation unit obtains the working current value, the oil pump output pressure value, the motor housing temperature value and the pump body internal oil temperature value during the vehicle driving process, and makes a difference between the working current value and the preset working current value to obtain the working current difference value, makes a difference between the oil pump output pressure value and the preset oil pump output pressure value to obtain the oil pump output pressure difference value, then makes a difference between the motor housing temperature value and the preset motor housing temperature threshold to obtain the motor housing temperature difference value, makes a difference between the pump body internal oil temperature value and the preset pump body internal oil temperature value to obtain the pump body oil temperature difference value, and marks the obtained working current difference value, oil pump output pressure difference value, motor housing temperature difference value and pump body oil temperature difference value as JC, JH, JD and JR respectively, and sends them to the first fault judgment unit; D002: The first fault integration unit normalizes the working current difference, the oil pump output pressure difference, the motor housing temperature difference and the pump body oil temperature difference and then enters them into the formula for calculation. The working condition deviation index JTS of the electronic oil pump is obtained, wherein R1, R2, R3 and R4 are the weight coefficients corresponding to the working current difference, the oil pump output pressure difference, the motor housing temperature difference and the pump body oil temperature difference respectively; D003: Extract the preset operating condition deviation index in the database, compare the real-time operating condition deviation index with the preset operating condition deviation index, if the real-time operating condition deviation index is greater than the preset operating condition deviation index, add one to the fault warning value of the electronic oil pump, and send the real-time operating condition deviation index to the vehicle driving characteristic module.

[0008] The vehicle driving characteristics module extracts vehicle speed data, acceleration data and driving mode data, and analyzes the electronic oil pump characteristics. The specific process is as follows: T001: The output end of the vehicle driving characteristic module is connected to the input end of the fault integral judgment module. The vehicle driving characteristic module is provided with an analysis unit and a second fault judgment unit. The analysis unit sets a preset driving period, divides the preset driving period into a number of preset driving sub-periods, collects each acceleration value of each preset driving sub-period, adds each acceleration value and divides it by the number of preset driving sub-periods to obtain the acceleration mean TE; T002: Obtain the corresponding maximum acceleration value within the preset driving time period, marked as the acceleration peak value TR; T003: Acquire each driving mode within the current preset driving period, and encode each driving mode respectively, i=1, 2, ..., n, i represents the code of the driving mode, and n represents the number of driving modes; T004: Calculate the frequency resolution within the preset driving period based on Fourier transform, set the sampling frequency and number of data points respectively and , using the formula Get frequency resolution , obtaining the maximum frequency point within the preset driving period, and obtaining the vehicle speed fluctuation frequency TY based on the maximum frequency point and the frequency resolution; the analysis unit sends the obtained acceleration mean value, acceleration peak value and vehicle speed fluctuation frequency to the second fault determination unit; T005: The second fault judgment unit substitutes the real-time operating condition deviation index, acceleration mean, acceleration peak and vehicle speed fluctuation frequency into the preset model for calculation. The driving influence fault association value TRW of the electronic oil pump is obtained, wherein P1, P2, P3 and P4 are preset proportional coefficients, which are 0.25, 0.56, 1.24 and 0.67 respectively. It can be seen from the formula that the larger the real-time working condition deviation value, the corresponding driving influence fault association value. The preset driving influence fault association threshold of the data center is extracted, and the obtained driving influence fault association value is compared with the preset driving influence fault association threshold. If the driving influence fault association value is greater than the preset driving influence fault association threshold, the fault warning value of the electronic oil pump is increased by two, and a secondary warning signal is generated and sent to the fault integral judgment module.

[0009] The battery management feature module extracts the battery power data and the charge and discharge current data. The specific process is as follows; F001: the output end of the battery management feature module is connected to the input end of the fault integral judgment module, and the input end of the battery management feature module is connected to the output end of the database, and the battery power value of each preset driving time period is obtained, and the battery power value of each battery is obtained, and any two adjacent battery power values ​​are added and divided by the preset driving time period to obtain the power change rate; F002: extract the standard battery power threshold in the database, mark each battery power time period within the preset driving time period when the battery power is less than the standard battery power threshold as a low-power duration period, count each low-power duration period in each preset driving time period, and obtain the total duration of low power; F003: Obtain the charging and discharging current values ​​within the preset driving time period, calculate the average of the charging and discharging current values ​​and obtain the average charging and discharging current; send the power change rate, the total duration of low power and the average charging and discharging current to the fault integration judgment module.

[0010] The fault integral judgment module sets the fault integral level and the secondary warning signal starts the fault integral unit to obtain the current fault level of the electronic oil pump and process it. The specific process is as follows: The fault integral judgment module is provided with a fault integral grade unit, a fault integral calculation unit and a processing unit. The fault integral calculation unit receives a secondary warning signal, and subtracts the real-time working condition deviation index from the preset working condition deviation index to obtain the working condition deviation difference, and respectively subtracts the acceleration mean, the acceleration peak and the vehicle speed fluctuation frequency from the corresponding acceleration standard mean, the acceleration standard peak and the vehicle speed standard fluctuation frequency to obtain the acceleration mean difference, the acceleration peak difference and the vehicle speed fluctuation frequency difference, and then subtracts the power change rate, the low power total duration and the charging and discharging current mean from the corresponding standard power change rate, the low power standard total duration and the standard charging and discharging current mean to obtain the power change difference, the low power duration difference and the charging and discharging current difference; the obtained real-time working condition deviation index, the acceleration mean difference, the acceleration peak difference, the vehicle speed fluctuation frequency difference, the power change difference, the low power duration difference and the charging and discharging current difference are added to obtain the real-time fault integral value; the fault integral calculation unit sends the real-time fault integral value to the fault integral grade unit for judgment; The fault integral level unit divides the current electronic oil pump into three levels, including minor fault level, moderate fault level and severe fault level. If the real-time fault integral value is between 0-30 points, it is judged as a minor fault level; if it is between 31-60 points, it is judged as a moderate fault level; if the real-time fault integral value is above 61 points, it is judged as a severe fault level; If it is determined to be a minor fault, a first-level warning signal is generated and sent to the vehicle display screen with a text description of "minor fault"; If it is determined to be a moderate fault level, a secondary warning signal will be generated, limiting the vehicle's output power by 50%, and the vehicle's voice system will issue a voice alarm "The electronic oil pump has a moderate fault, and the vehicle has entered the safety protection mode. Please drive carefully according to the prompts on the dashboard and contact the maintenance service as soon as possible"; If it is determined to be a serious fault level, a third-level warning signal will be generated, the current vehicle will be stopped, the cloud server will be connected, the current vehicle position will be located through the cloud server, and the location will be sent to the corresponding maintenance personnel's mobile terminal.

[0011] Reference Figure 2 As shown, the second aspect of the present invention provides a fault diagnosis method for an electronic oil pump of a new energy vehicle, and the specific steps are as follows: Step 1: Multi-category collection: electronic oil pump parameters, vehicle driving data and battery management data are collected respectively, and classified storage units are set to store them respectively; Step 2: Extract the characteristics of the electronic oil pump based on the motor current data, pump body pressure data and temperature data; Step 3: The vehicle driving characteristics are extracted based on the vehicle speed data, acceleration data and driving mode data, and analyzed in combination with the electronic oil pump characteristic results; Step 4: The battery management feature extracts the battery power data and the charge and discharge current data, and sends the acquired power change rate, total duration of low power, and average charge and discharge current to the fault integral judgment; Step 5: Fault integral determination Based on the set fault integral level, the secondary warning signal activates the fault integral unit to obtain the current fault level of the electronic oil pump and process it.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: the fault integral determination module divides the fault into minor fault level, moderate fault level and severe fault level according to the real-time fault integral value. This classification method can provide different levels of warnings to the driver according to the severity of the fault. For example, in case of minor fault, the driver can arrange for inspection at a convenient time to avoid excessive tension; in case of moderate fault, the vehicle limits power output and voice prompts the driver to enter safety protection mode and contact maintenance to prevent the fault from worsening; in case of severe fault, the vehicle will be stopped immediately and the vehicle position will be located to notify the maintenance personnel to ensure the safety of the vehicle and personnel; The electronic oil pump feature extraction module calculates the working current difference, oil pump output pressure difference, motor housing temperature difference and pump body oil temperature difference, and normalizes them to obtain the working condition deviation index, which can accurately quantify the degree of deviation between the working state of the electronic oil pump and the normal state.

[0013] The acceleration mean, peak value, speed fluctuation frequency and other features extracted by the vehicle driving characteristic module are combined with the electronic oil pump data to further analyze the impact of driving conditions on the oil pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. The following drawings are not intentionally scaled to the actual size, and the focus is on illustrating the main purpose of the present invention.

[0015] Figure 1 It is a principle block diagram of the present invention.

[0016] Figure 2 It is a diagram of the method steps of the present invention. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work also fall within the scope of protection of the present invention.

[0018] Please refer to Figure 1 As shown, the first aspect of the present invention provides a fault diagnosis system for an electronic oil pump of a new energy vehicle, comprising multiple types of acquisition modules, an electronic oil pump feature extraction module, a vehicle driving feature module, a battery management feature module, a fault integration judgment module, a cloud server and a database.

[0019] The multi-class acquisition module collects the electronic oil pump parameters, vehicle driving data and battery management data respectively, and sets the classified storage units to store them respectively. The specific process is as follows: The multi-type acquisition module is provided with an acquisition unit and a classification storage unit. Various types of sensors are installed on the electronic oil pump. The various types of sensors include current sensors, pump body pressure sensors and temperature sensors. The operation status of the electronic oil pump is collected in real time and integrated to obtain the parameters of the electronic oil pump. The input end of the acquisition unit is connected to the output end of the vehicle driving computer and the battery management terminal. The data information of the vehicle in the running state is collected in real time to obtain the vehicle driving data. The battery management data of the vehicle in the running state is collected in real time. The acquisition unit sends the electronic oil pump parameters, vehicle driving data and battery management data to the classification storage unit. The classification storage unit is respectively provided with an electronic oil pump storage area, a vehicle driving data storage area and a battery management data storage area, and each type of data is stored in the corresponding storage area; the output end of the multi-category acquisition module is connected to the input end of the electronic oil pump feature extraction module, the vehicle driving feature module and the battery management feature module, and the obtained data is sent to each module respectively.

[0020] The electronic oil pump feature extraction module extracts motor current data, pump body pressure data and temperature data. The specific process is as follows: D001: The output end of the electronic oil pump feature extraction module is connected to the input end of the vehicle driving feature extraction module. The electronic oil pump feature extraction module is provided with a deviation calculation unit and a first fault integration unit. The deviation calculation unit obtains the working current value, the oil pump output pressure value, the motor housing temperature value and the pump body internal oil temperature value during the vehicle driving process, and makes a difference between the working current value and the preset working current value to obtain the working current difference value, makes a difference between the oil pump output pressure value and the preset oil pump output pressure value to obtain the oil pump output pressure difference value, then makes a difference between the motor housing temperature value and the preset motor housing temperature threshold to obtain the motor housing temperature difference value, makes a difference between the pump body internal oil temperature value and the preset pump body internal oil temperature value to obtain the pump body oil temperature difference value, and marks the obtained working current difference value, oil pump output pressure difference value, motor housing temperature difference value and pump body oil temperature difference value as JC, JH, JD and JR respectively, and sends them to the first fault judgment unit; D002: The first fault integration unit normalizes the working current difference, the oil pump output pressure difference, the motor housing temperature difference and the pump body oil temperature difference and then enters them into the formula for calculation. The working condition deviation index JTS of the electronic oil pump is obtained, wherein R1, R2, R3 and R4 are the weight coefficients corresponding to the working current difference, the oil pump output pressure difference, the motor housing temperature difference and the pump body oil temperature difference respectively; D003: Extract the preset operating condition deviation index in the database, compare the real-time operating condition deviation index with the preset operating condition deviation index, if the real-time operating condition deviation index is greater than the preset operating condition deviation index, add one to the fault warning value of the electronic oil pump, and send the real-time operating condition deviation index to the vehicle driving characteristic module.

[0021] The vehicle driving characteristics module extracts vehicle speed data, acceleration data and driving mode data, and analyzes the electronic oil pump characteristics. The specific process is as follows: T001: The output end of the vehicle driving characteristic module is connected to the input end of the fault integral judgment module. The vehicle driving characteristic module is provided with an analysis unit and a second fault judgment unit. The analysis unit sets a preset driving period, divides the preset driving period into a number of preset driving sub-periods, collects each acceleration value of each preset driving sub-period, adds each acceleration value and divides it by the number of preset driving sub-periods to obtain the acceleration mean TE; T002: Obtain the corresponding maximum acceleration value within the preset driving time period, marked as the acceleration peak value TR; T003: Acquire each driving mode within the current preset driving period, and encode each driving mode respectively, i=1, 2, ..., n, i represents the code of the driving mode, and n represents the number of driving modes; T004: Calculate the frequency resolution within the preset driving period based on Fourier transform, set the sampling frequency and number of data points respectively and , using the formula Get frequency resolution , obtaining the maximum frequency point within the preset driving period, and obtaining the vehicle speed fluctuation frequency TY based on the maximum frequency point and the frequency resolution; the analysis unit sends the obtained acceleration mean value, acceleration peak value and vehicle speed fluctuation frequency to the second fault determination unit; T005: The second fault judgment unit substitutes the real-time operating condition deviation index, acceleration mean, acceleration peak and vehicle speed fluctuation frequency into the preset model for calculation. The driving influence fault association value TRW of the electronic oil pump is obtained, wherein P1, P2, P3 and P4 are preset proportional coefficients, which are 0.25, 0.56, 1.24 and 0.67 respectively. It can be seen from the formula that the larger the real-time working condition deviation value, the corresponding driving influence fault association value. The preset driving influence fault association threshold of the data center is extracted, and the obtained driving influence fault association value is compared with the preset driving influence fault association threshold. If the driving influence fault association value is greater than the preset driving influence fault association threshold, the fault warning value of the electronic oil pump is increased by two, and a secondary warning signal is generated and sent to the fault integral judgment module.

[0022] The battery management feature module extracts the battery power data and the charge and discharge current data. The specific process is as follows: F001: the output end of the battery management feature module is connected to the input end of the fault integral judgment module, and the input end of the battery management feature module is connected to the output end of the database, and the battery power value of each preset driving time period is obtained, and the battery power value of each battery is obtained, and any two adjacent battery power values ​​are added and divided by the preset driving time period to obtain the power change rate; F002: extract the standard battery power threshold in the database, mark each battery power time period within the preset driving time period when the battery power is less than the standard battery power threshold as a low-power duration period, count each low-power duration period in each preset driving time period, and obtain the total duration of low power; F003: Obtain the charging and discharging current values ​​within the preset driving time period, calculate the average of the charging and discharging current values ​​and obtain the average charging and discharging current; send the power change rate, the total duration of low power and the average charging and discharging current to the fault integration judgment module.

[0023] The fault integral judgment module sets the fault integral level and the secondary warning signal starts the fault integral unit to obtain the current fault level of the electronic oil pump and process it. The specific process is as follows: The fault integral judgment module is provided with a fault integral grade unit, a fault integral calculation unit and a processing unit. The fault integral calculation unit receives a secondary warning signal, and subtracts the real-time working condition deviation index from the preset working condition deviation index to obtain the working condition deviation difference, and respectively subtracts the acceleration mean, the acceleration peak and the vehicle speed fluctuation frequency from the corresponding acceleration standard mean, the acceleration standard peak and the vehicle speed standard fluctuation frequency to obtain the acceleration mean difference, the acceleration peak difference and the vehicle speed fluctuation frequency difference, and then subtracts the power change rate, the low power total duration and the charging and discharging current mean from the corresponding standard power change rate, the low power standard total duration and the standard charging and discharging current mean to obtain the power change difference, the low power duration difference and the charging and discharging current difference; the obtained real-time working condition deviation index, the acceleration mean difference, the acceleration peak difference, the vehicle speed fluctuation frequency difference, the power change difference, the low power duration difference and the charging and discharging current difference are added to obtain the real-time fault integral value; the fault integral calculation unit sends the real-time fault integral value to the fault integral grade unit for judgment; The fault integral level unit divides the current electronic oil pump into three levels, including minor fault level, moderate fault level and severe fault level. If the real-time fault integral value is between 0-30 points, it is judged as a minor fault level; if it is between 31-60 points, it is judged as a moderate fault level; if the real-time fault integral value is above 61 points, it is judged as a severe fault level; If it is determined to be a minor fault, a first-level warning signal is generated and sent to the vehicle display screen with a text description of "minor fault"; If it is determined to be a moderate fault level, a secondary warning signal will be generated, limiting the vehicle's output power by 50%, and the vehicle's voice system will issue a voice alarm "The electronic oil pump has a moderate fault, and the vehicle has entered the safety protection mode. Please drive carefully according to the prompts on the dashboard and contact the maintenance service as soon as possible"; If it is determined to be a serious fault level, a third-level warning signal will be generated, the current vehicle will be stopped, the cloud server will be connected, the current vehicle position will be located through the cloud server, and the location will be sent to the corresponding maintenance personnel's mobile terminal.

[0024] Reference Figure 2 As shown, the second aspect of the present invention provides a fault diagnosis method for an electronic oil pump of a new energy vehicle, and the specific steps are as follows: Step 1: Multi-category collection: electronic oil pump parameters, vehicle driving data and battery management data are collected respectively, and classified storage units are set to store them respectively; Step 2: Extract the characteristics of the electronic oil pump based on the motor current data, pump body pressure data and temperature data; Step 3: The vehicle driving characteristics are extracted based on the vehicle speed data, acceleration data and driving mode data, and analyzed in combination with the electronic oil pump characteristic results; Step 4: The battery management feature extracts the battery power data and the charge and discharge current data, and sends the acquired power change rate, total duration of low power, and average charge and discharge current to the fault integral judgment; Step 5: Fault integral determination Based on the set fault integral level, the secondary warning signal activates the fault integral unit to obtain the current fault level of the electronic oil pump and process it.

[0025] The above is an explanation of the present invention and should not be considered as a limitation thereof. Although several exemplary embodiments of the present invention have been described, it will be readily appreciated by those skilled in the art that many modifications may be made to the exemplary embodiments without departing from the novel teachings and advantages of the present invention. Therefore, all such modifications are intended to be included within the scope of the present invention as defined in the claims. It should be understood that the above is an explanation of the present invention and should not be considered as being limited to the specific embodiments disclosed, and modifications to the disclosed embodiments and other embodiments are intended to be included within the scope of the appended claims. The present invention is defined by the claims and their equivalents.

Claims

1. A fault diagnosis system for an electronic oil pump of a new energy vehicle, comprising a multi-type acquisition module, a vehicle driving characteristic module, a battery management characteristic module, a fault integral determination module, a cloud server and a database, characterized in that: It also includes an electronic oil pump feature extraction module; The electronic oil pump feature extraction module extracts data based on the motor current data, pump body pressure data and temperature data. The output end of the electronic oil pump feature extraction module is connected to the input end of the vehicle driving feature extraction module. The electronic oil pump feature extraction module is provided with a deviation calculation unit and a first fault integration unit. The deviation calculation unit obtains the working current value, the oil pump output pressure value, the motor housing temperature value and the pump body internal oil temperature value during vehicle driving, and subtracts the working current value from the preset working current value to obtain the working current difference, and subtracts the oil pump output pressure value from the preset oil pump output pressure value to obtain the oil pump output pressure difference, and then subtracts the motor housing temperature value from the preset motor housing temperature threshold to obtain the motor housing temperature difference, and subtracts the pump body internal oil temperature value from the preset pump body internal oil temperature value to obtain the pump body oil temperature difference, and sends the obtained working current difference, oil pump output pressure difference, motor housing temperature difference and pump body oil temperature difference to the first fault judgment unit.

2. A fault diagnosis system for an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: The electronic oil pump feature extraction module also includes a first fault integration unit, and the specific process is as follows: The first fault integration unit normalizes the working current difference, the oil pump output pressure difference, the motor housing temperature difference and the pump body oil temperature difference and then enters them into the formula for calculation. The working condition deviation index JTS of the electronic oil pump is obtained, where JC, JH, JD and JR are the working current difference, the oil pump output pressure difference, the motor housing temperature difference and the pump body oil temperature difference respectively; R1, R2, R3 and R4 are the set weight coefficients corresponding to the working current difference, the oil pump output pressure difference, the motor housing temperature difference and the pump body oil temperature difference respectively; Extract the preset operating condition deviation index in the database, compare the real-time operating condition deviation index with the preset operating condition deviation index, if the real-time operating condition deviation index is greater than the preset operating condition deviation index, add one to the fault warning value of the electronic oil pump, and send the real-time operating condition deviation index to the vehicle driving characteristic module.

3. A fault diagnosis system for an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: The vehicle driving characteristics module extracts vehicle speed data, acceleration data and driving mode data, and analyzes the electronic oil pump characteristics. The specific process is as follows: The output end of the vehicle driving characteristic module is connected to the input end of the fault integral determination module. The vehicle driving characteristic module is provided with an analysis unit and a second fault determination unit. The analysis unit sets a preset driving period, divides the preset driving period into a plurality of preset driving sub-periods, collects each acceleration value of each preset driving sub-period, adds each acceleration value and divides it by the number of preset driving sub-periods to obtain an acceleration mean TE. Obtain the corresponding maximum acceleration value within the preset driving time period, marked as the acceleration peak value TR; Acquire each driving mode within the current preset driving period, and encode each driving mode respectively; The frequency resolution within the preset driving period is calculated based on Fourier transform, and the sampling frequency and number of data points are set respectively. and , using the formula Get frequency resolution , obtain the maximum frequency point within the preset driving period, and obtain the vehicle speed fluctuation frequency TY based on the maximum frequency point and the frequency resolution; the analysis unit sends the obtained acceleration mean, acceleration peak and vehicle speed fluctuation frequency to the second fault judgment unit.

4. A fault diagnosis system for an electronic oil pump of a new energy vehicle according to claim 3, characterized in that: The specific determination process of the second fault determination unit is as follows: Substitute the real-time operating condition deviation index, acceleration mean, acceleration peak and vehicle speed fluctuation frequency into the preset model The driving impact fault association value TRW of the electronic oil pump is calculated, wherein P1, P2, P3 and P4 are preset proportional coefficients, the preset driving impact fault association threshold of the data center is extracted, and the obtained driving impact fault association value is compared with the preset driving impact fault association threshold. If the driving impact fault association value is greater than the preset driving impact fault association threshold, the fault warning value of the electronic oil pump is increased by two, and a secondary warning signal is generated and sent to the fault integration judgment module.

5. A fault diagnosis system for an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: The battery management feature module extracts the battery power data and the charge and discharge current data. The specific process is as follows; The output end of the battery management feature module is connected to the input end of the fault integral determination module, and the input end of the battery management feature module is connected to the output end of the database, and the battery power value of each preset driving time period is obtained to obtain each battery power value, and any two adjacent battery power values ​​are added and divided by the preset driving time period to obtain the power change rate; Extract the standard battery power threshold in the database, mark each battery power time period within the preset driving time period when the battery power is less than the standard battery power threshold as a low-power duration period, count each low-power duration period in each preset driving time period, and obtain the total duration of low power; Obtain each charging and discharging current value within a preset driving time period, and calculate the average of each charging and discharging current value to obtain the average charging and discharging current value; The rate of change of power, the total duration of low power and the average value of charging and discharging current are sent to the fault integration judgment module.

6. A fault diagnosis system for an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: The fault integral judgment module sets the fault integral level and the secondary warning signal starts the fault integral unit to obtain the current fault level of the electronic oil pump and process it. The specific process is as follows: The fault integral judgment module is provided with a fault integral grade unit, a fault integral calculation unit and a processing unit. The fault integral calculation unit receives a secondary warning signal, and subtracts the real-time working condition deviation index from the preset working condition deviation index to obtain the working condition deviation difference, and respectively subtracts the acceleration mean, the acceleration peak and the vehicle speed fluctuation frequency from the corresponding acceleration standard mean, the acceleration standard peak and the vehicle speed standard fluctuation frequency to obtain the acceleration mean difference, the acceleration peak difference and the vehicle speed fluctuation frequency difference, and then subtracts the power change rate, the low power total duration and the charging and discharging current mean from the corresponding standard power change rate, the low power standard total duration and the standard charging and discharging current mean to obtain the power change difference, the low power duration difference and the charging and discharging current difference; the obtained real-time working condition deviation index, the acceleration mean difference, the acceleration peak difference, the vehicle speed fluctuation frequency difference, the power change difference, the low power duration difference and the charging and discharging current difference are added to obtain the real-time fault integral value; the fault integral calculation unit sends the real-time fault integral value to the fault integral grade unit for judgment.

7. A fault diagnosis system for an electronic oil pump of a new energy vehicle according to claim 6, characterized in that: The fault integral determination module also includes a fault integral level unit and a processing unit. The specific operation process is as follows: The current electronic oil pump is divided into three levels, including minor fault level, moderate fault level and severe fault level. If the real-time fault integral value is between 0-30 points, it is judged as a minor fault level; if it is between 31-60 points, it is judged as a moderate fault level; if the real-time fault integral value is above 61 points, it is judged as a severe fault level; If it is determined to be a minor fault, a first-level warning signal is generated and sent to the vehicle display screen in the form of a minor fault text description; If it is determined to be a moderate fault level, a secondary warning signal will be generated, limiting the vehicle's output power by 50%, and the vehicle's voice system will issue a voice alarm that the electronic oil pump has a moderate fault and the vehicle has entered a safety protection mode. Please follow the instrument panel prompts to drive carefully and contact maintenance service as soon as possible; If it is determined to be a serious fault level, a third-level warning signal will be generated, the current vehicle will be stopped, the cloud server will be connected, the current vehicle position will be located through the cloud server, and the location will be sent to the corresponding maintenance personnel's mobile terminal.

8. A fault diagnosis system for an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: The multi-class acquisition module collects the electronic oil pump parameters, vehicle driving data and battery management data respectively, and sets the classified storage units to store them respectively. The specific process is as follows: The multi-type acquisition module is provided with an acquisition unit and a classification storage unit. Various types of sensors are installed on the electronic oil pump. The various types of sensors include current sensors, pump pressure sensors and temperature sensors. The operating status of the electronic oil pump is collected in real time and integrated to obtain the electronic oil pump parameters. The input end of the acquisition unit is connected to the output end of the vehicle's driving computer and the battery management terminal. The data information of the vehicle in the operating state is collected in real time to obtain the vehicle driving data. The battery management data of the vehicle in the operating state is collected in real time. The acquisition unit sends the electronic oil pump parameters, vehicle driving data and battery management data to the classification storage unit.

9. A fault diagnosis system for an electronic oil pump of a new energy vehicle according to claim 8, characterized in that: The multi-class acquisition module also includes a classification storage unit, and the specific process is as follows: The classification storage unit is respectively provided with an electronic oil pump storage area, a vehicle driving data storage area and a battery management data storage area, and each type of data is stored in the corresponding storage area; the output end of the multi-category acquisition module is connected to the input end of the electronic oil pump feature extraction module, the vehicle driving feature module and the battery management feature module, and the obtained data is sent to each module respectively.

10. A fault diagnosis method for an electronic oil pump of a new energy vehicle, characterized in that: A fault diagnosis system for an electronic oil pump of a new energy vehicle as described in any one of claims 1 to 9, wherein the specific steps are as follows: Step 1: Multi-category collection: electronic oil pump parameters, vehicle driving data and battery management data are collected separately, and classified storage units are set to store them separately; Step 2: Extracting the characteristics of the electronic oil pump: extracting the motor current data, pump body pressure data and temperature data; Step 3: Vehicle driving characteristics: Based on the extraction of vehicle speed data, acceleration data and driving mode data, combined with the analysis of electronic oil pump characteristic results; Step 4: Battery management features: extract the battery power data and charge and discharge current data, and send the acquired power change rate, total duration of low power, and charge and discharge current average to the fault integral judgment; Step 5: Fault integral determination: According to the set fault integral level, the secondary warning signal activates the fault integral unit to obtain the current fault level of the electronic oil pump and process it.

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