Power assembly collision detection system and method with frequency filtering

Abstract

The invention discloses a power assembly collision detection system with a frequency filtering function. The power assembly collision detection system comprises a data setting module which is used for adjusting the rotating speed and the torque of a motor to the set rotating speed and the set torque; the acceleration sensor is used for collecting vibration signals of the power assembly in all time periods. And the kurtosis numerical value calculation module performs low-pass filtering on the vibration signal amplitude peak value, and calculates a kurtosis numerical value by using the vibration signal amplitude peak value after the low-pass filtering. According to the invention, high-frequency energy can be eliminated, and the problems of high error interception rate, false burrs and high missing interception rate in the prior art are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of powertrain detection, and in particular to a powertrain collision detection system and method with frequency filtering. Background Art

[0002] With the advancement of the global electric vehicle craze, component integration has become an inevitable trend. New energy vehicles, especially electric vehicles, are usually quieter than traditional fuel vehicles due to the working principle of their electric motors. Therefore, NVH (Noise, Vibration and Harshness) testing has become an important indicator of vehicle performance and user experience.

[0003] The NVH problems of new energy vehicles mainly come from the collision of shaft teeth and vibration signal burrs in the powertrain. These problems are generally intercepted by visual inspection and NVH detection. Among them, the detection method is to evaluate through the Kurtosis indicator (used to evaluate the number and density of collision damage). However, the existing indicator identification still has the problems of high false interception rate and missed interception of vibration signal burrs.

[0004] Therefore, it is a technical problem to be solved urgently to invent a powertrain collision detection system that can remove false glitches and eliminate high-frequency energy through frequency filtering to reduce the false interception rate and missed interception rate. Summary of the invention

[0005] The purpose of the present invention is to provide a powertrain collision detection system and method with frequency filtering. The present invention can eliminate false glitches in the powertrain vibration detection signal, eliminate high-frequency energy in the powertrain vibration detection signal, and reduce the technical problems of false interception rate and missed interception rate of vibration signal glitches.

[0006] To achieve this purpose, the present invention is designed to provide a powertrain collision detection system with frequency filtering, which includes:

[0007] The data setting module is used to adjust the motor speed and motor torque to the set motor speed and motor torque;

[0008] The acceleration sensor is used to collect vibration signals of the powertrain at various time periods when the motor is running at a set motor speed and motor torque;

[0009] The peak value calculation module is used to perform low-pass filtering on the amplitude peak value of the vibration signal in each time period, and calculate the peak value of each time period using the amplitude peak value of the vibration signal in each time period after low-pass filtering.

[0010] Preferably, the motor speed setting range is 2000rpm to 5000rpm.

[0011] Preferably, the motor torque setting range is 5Nm to 20Nm.

[0012] Preferably, the peak value calculation module performs low-pass filtering on the peak amplitude of the vibration signal through TasAlyser software to filter out frequencies above 2000 Hz in the vibration signal.

[0013] Preferably, the Kurtosis peak value is a characteristic number that characterizes the height of the peak of the probability density distribution curve at the mean value. The larger the Kurtosis peak value, the larger the variance of the vibration signal. The Kurtosis peak value is proportional to the variance of the vibration signal generated by the powertrain collision interference. The Kurtosis peak value is used to characterize the powertrain collision situation.

[0014] Beneficial effects of the present invention:

[0015] The present invention provides a powertrain collision detection system with frequency filtering, which performs low-pass filtering on the peak amplitude of a vibration signal, filters out frequencies above 2000 Hz in the vibration signal, and then calculates a Kurtosis value.

[0016] High-frequency energy may contain noise or interference signals, which may be mistakenly identified by the system as target signals, resulting in an increase in the false interception rate. As the impact of the integrated drive system NVH on the performance of the entire vehicle becomes greater, the vibration and noise of the drive system directly affects the NVH performance of electric vehicles. By reducing these high-frequency interferences, the detection system can more accurately identify collision events, thereby reducing the false interception rate and missed interception rate. This solution eliminates high-frequency energy through filtering, solving the problem of high false interception rate and high missed interception rate in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention;

[0018] Figure 2 It is an implementation flow chart of the present invention. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions 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 part of the embodiments of the present invention, not all of the embodiments. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0021] Example 1

[0022] A powertrain collision detection system with frequency filtering, such as Figure 1 As shown, it includes:

[0023] The data setting module is used to adjust the motor speed and motor torque to the set motor speed and motor torque;

[0024] The acceleration sensor is used to collect vibration signals of the powertrain at various time periods when the motor is running at a set motor speed and motor torque;

[0025] The peak value calculation module is used to perform low-pass filtering on the amplitude peak value of the vibration signal in each time period, and calculate the peak value of each time period using the amplitude peak value of the vibration signal in each time period after low-pass filtering.

[0026] In the above technical solution, the motor speed setting range is 2000rpm~5000rpm; the motor torque setting range is 5Nm~20Nm; the vibration characteristics of the motor are closely related to its speed and torque. Under the above speed and torque, the vibration signal generated by the motor has specific frequency and amplitude characteristics, thereby having relatively stable frequency and amplitude characteristics, and can also ensure that each test is carried out under the same conditions, thereby improving the accuracy and comparability of the test results. At this time, the collected signal can more truly reflect the operating state of the powertrain, avoiding signal interference and errors caused by changes in speed and torque; if the motor speed and torque are unstable or not within the set range, the vibration signal of the powertrain will be interfered, resulting in inaccurate data collected by the acceleration sensor, which will directly affect the calculation of the peak value and the accuracy of bump detection;

[0027] During actual operation, the speed and torque of the motor may change due to a variety of external factors, such as load changes, power supply voltage fluctuations, etc. These factors may cause fluctuations and interference in the vibration signal, thereby affecting the accuracy of fault detection. By collecting signals at the set motor speed and torque, these changes can be more easily captured, minimizing the interference of these external factors. By real-time monitoring of significant changes in vibration signals, signs of faults can be discovered earlier, potential fault trends can be discovered in a timely manner, providing strong support for repairs and maintenance, and improving the sensitivity of fault detection.

[0028] In the above technical solutions, the design of the low-pass filter is usually targeted at a specific frequency range. Under the set motor speed and torque, the vibration signal of the powertrain may be concentrated in a specific frequency range, which enables the low-pass filter to more effectively remove high-frequency noise and retain useful vibration information.

[0029] In the above technical solution, the peak value calculation module performs low-pass filtering on the peak amplitude of the vibration signal to filter out the frequencies above 2000 Hz in the vibration signal. The vibration signal of the powertrain usually contains multiple frequency components, among which the low-frequency components are often closely related to the vibration state of the mechanical parts, while the high-frequency components may come from multiple interference sources. Therefore, removing high-frequency noise through low-pass filtering can more accurately reflect the vibration state of the mechanical parts, effectively remove these high-frequency noises, purify the vibration signal, and make the amplitude peak more accurate; under the influence of high-frequency noise, the amplitude distribution form of the signal may change, resulting in inaccurate peak value, so before calculating the peak value, the amplitude peak needs to be low-pass filtered to eliminate the influence of high-frequency noise.

[0030] In the above technical solution, the specific calculation formula for calculating the peak state value in the peak state value calculation module using the peak value of the vibration signal amplitude after low-pass filtering is:

[0031]

[0032] Among them, Kurtosis is the peak value of a certain period of time, X is the peak amplitude value of the vibration signal in a certain period of time after low-pass filtering, μ is the average value of the peak amplitude value of the vibration signal in a certain period of time after low-pass filtering, σ is the standard deviation of the peak amplitude value of the vibration signal in a certain period of time after low-pass filtering, and E is expressed as the expected value of the peak amplitude value of the vibration signal in a certain period of time after low-pass filtering. The expected value of the peak amplitude value is used to describe the average level of the peak amplitude in the vibration waveform, and the standard deviation of the peak amplitude value is used to measure the degree of signal discreteness, which reflects the fluctuation size of the vibration signal.

[0033] In the above technical solution, by adding the Kurtosis calculation method after low-pass filtering, unqualified powertrain vibration signals are distinguished from qualified powertrain vibration signals and accurately intercepted.

[0034] In the above technical solution, by adding the Kurtosis calculation method after low-pass filtering, unqualified powertrain vibration signals are distinguished from qualified powertrain vibration signals and accurately intercepted.

[0035] In the above technical solution, the Kurtosis kurtosis value is a characteristic number that characterizes the height of the peak of the probability density distribution curve at the mean value, which reflects the sharpness of the peak of the probability density distribution curve. The kurtosis coefficient of the sample is a statistic compared with the normal distribution. The larger the Kurtosis kurtosis value, the larger the variance of the vibration signal. The Kurtosis kurtosis value is proportional to the variance of the vibration signal generated by the powertrain collision interference. The powertrain collision is characterized by the Kurtosis kurtosis value. In this embodiment, a comparison table of Kurtosis kurtosis value and powertrain collision degree is obtained through repeated experiments, and the corresponding powertrain collision degree is determined according to the current Kurtosis kurtosis value combined with the comparison table.

[0036] Example 2

[0037] A powertrain collision detection method with frequency filtering, such as Figure 2 As shown, the signal acquisition card in the NVH sensor collects the vibration signal of the powertrain of the object under test, performs low-pass filtering on the peak amplitude of the vibration signal, filters out the frequencies above 2000 Hz in the vibration signal, and then calculates the peak value.

[0038] A specific analysis method for powertrain collision detection with frequency filtering includes the following steps:

[0039] Adjust the motor speed and motor torque to the set motor speed and motor torque;

[0040] When the motor runs at the set motor speed and motor torque, the vibration signals of the powertrain at each time period are collected;

[0041] The peak amplitude value of the vibration signal in each time period is low-pass filtered, and the peak amplitude value of each time period is calculated using the peak amplitude value of the vibration signal in each time period after low-pass filtering.

[0042] Example 3

[0043] A computer program product comprises a computer program, wherein when the computer program is executed by a processor, the steps of the method described in Embodiment 2 are implemented.

[0044] Example 4

[0045] An electronic device comprises: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the steps of the method described in Example 2 by executing the computer instructions.

[0046] Example 5

[0047] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method described in Example 2 are implemented.

[0048] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0049] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A system that specifies the functions of a box or multiple boxes.

[0050] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction system, which is implemented in the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0051] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0052] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A powertrain collision detection system with frequency filtering, characterized in that: It includes: The data setting module is used to adjust the motor speed and motor torque to the set motor speed and motor torque; The acceleration sensor is used to collect vibration signals of the powertrain at various time periods when the motor is running at a set motor speed and motor torque; The peak value calculation module is used to perform low-pass filtering on the amplitude peak value of the vibration signal in each time period, and calculate the peak value of each time period using the amplitude peak value of the vibration signal in each time period after low-pass filtering.

2. A powertrain collision detection system with frequency filtering according to claim 1, characterized in that: The set motor speed range is 2000rpm~5000rpm.

3. A powertrain collision detection system with frequency filtering according to claim 1, characterized in that: The set motor torque range is 5Nm to 20Nm.

4. A powertrain collision detection system with frequency filtering according to claim 1, characterized in that: The peak value calculation module performs low-pass filtering on the peak amplitude of the vibration signal in each period, filtering out the frequencies above 2000 Hz in the peak amplitude of the vibration signal.

5. The powertrain collision detection system with frequency filtering according to claim 1, characterized in that: The specific method for calculating the peak state value of each time period in the peak state value calculation module using the peak amplitude of the vibration signal in each time period after low-pass filtering is as follows: Among them, Kurtosis is the peak value of a certain period of time, X is the peak amplitude of the vibration signal in a certain period of time after low-pass filtering, μ is the average value of the peak amplitude of the vibration signal in a certain period of time after low-pass filtering, σ is the standard deviation of the peak amplitude of the vibration signal in a certain period of time after low-pass filtering, and E is represented by the expected value of the peak amplitude of the vibration signal in a certain period of time after low-pass filtering.

6. A powertrain collision detection system with frequency filtering according to claim 5, characterized in that: The Kurtosis value is a characteristic number that characterizes the height of the peak of the probability density distribution curve at the mean value. The larger the Kurtosis value, the greater the variance of the vibration signal. The Kurtosis value is proportional to the variance of the vibration signal caused by the powertrain collision interference. The Kurtosis value is used to characterize the powertrain collision situation.

7. A powertrain collision detection method with frequency filtering, characterized in that: It includes the following steps: Adjust the motor speed and motor torque to the set motor speed and motor torque; When the motor runs at the set motor speed and motor torque, the vibration signals of the powertrain at each time period are collected; The peak amplitude value of the vibration signal in each time period is low-pass filtered, and the peak amplitude value of each time period is calculated using the peak amplitude value of the vibration signal in each time period after low-pass filtering.

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method described in claim 7 are implemented.

9. An electronic device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the steps of the method as claimed in claim 7 by executing the computer instructions.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to claim 7 are implemented.

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