Method, device and electronic equipment for evaluating radiation noise of a housing

Abstract

The application provides a shell radiation noise evaluation method and device and electronic equipment. The method comprises the following steps: obtaining a modal vibration mode of a shell structure; determining a plurality of measurement points of the shell structure based on a modal vibration region of the modal vibration mode; determining vibration transmissibility data of each measurement point through a vibration sensor when each measurement point is tapped; determining vibration overall radiation energy of the shell structure based on the vibration transmissibility data of the plurality of measurement points, and determining shell radiation noise of the shell structure based on the vibration overall radiation energy. In this way, the shell radiation noise level in the actual operation process of the shell structure can be effectively predicted by carrying out tapping test on the measurement points of different parts of the shell structure to obtain the vibration transmissibility data without running test on the electric drive bench, so that the NVH performance of the electric drive product and the comfort of the new energy vehicle are improved.

Description

Technical Field

[0001] This invention relates to the field of electric drive vibration and noise analysis technology, and in particular to a method, apparatus and electronic device for evaluating shell radiated noise. Background Technology

[0002] Housing modal noise is one of the main noise sources in electric drives. When a vehicle accelerates or decelerates, if the excitation frequencies corresponding to the motor and gears are close to the motor housing modal frequencies, a sudden resonant noise will form at the housing modal frequencies. This has a significant impact on the NVH (Noise, Vibration, and Harshness) performance of new energy vehicles. Because housing modal noise has obvious narrow-band frequency characteristics, it is easily perceived as a howling sudden change in the cabin of new energy vehicles, directly affecting the sound quality inside the vehicle and the comfort of the passengers.

[0003] In recent years, with the rapid development of new energy vehicles, more and more customers are choosing new energy vehicles and paying more and more attention to the NVH performance of the vehicle. Most of the noise perception in the vehicle comes from the sudden change in howling caused by electric drive resonance.

[0004] Currently, existing technical solutions can predict shell noise in the time domain by collecting tangential / normal vibration signals of the shell and constructing a predictive model. Alternatively, the radiated sound power level of the shell can be calculated through CAE (Computer-Aided Engineering) simulation. However, these technical solutions evaluate radiated noise based on formulas or theories, lacking a benchmark against actual models, and cannot accurately capture the prominence of the shell's modal noise. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a method, apparatus and electronic device for evaluating shell radiated noise, so as to solve the problem that simulation or theoretical formula calculation cannot accurately and effectively evaluate the sudden changes in electric drive noise caused by modal resonance of the shell of a physical product, thereby improving the sound quality in the vehicle and the user experience.

[0006] In a first aspect, embodiments of the present invention provide a method for evaluating shell radiated noise, the method comprising: acquiring the mode shape of the shell structure; determining multiple measurement points of the shell structure based on the modal vibration region of the mode shape; determining the vibration transfer function data of each measurement point by means of a vibration sensor when each measurement point is struck; determining the overall vibration radiated energy of the shell structure based on the vibration transfer function data of the multiple measurement points; and determining the shell radiated noise of the shell structure based on the overall vibration radiated energy.

[0007] In an optional embodiment of this application, after the step of determining the vibration transfer function data of each measurement point by vibration sensor, the method further includes: if the vibration amplitude of the vibration transfer function data of the measurement point is greater than a preset threshold, adjusting the shell structure of the measurement point.

[0008] In an optional embodiment of this application, the above method further includes: placing the housing structure on an electric drive test bench for testing to obtain the housing radiated noise of the housing structure.

[0009] In an optional embodiment of this application, the step of determining multiple measurement points of the shell structure based on the modal vibration region of the modal mode includes: taking the region where the vibration amplitude of the first three modal modes is greater than a preset threshold as the modal vibration region; and determining multiple measurement points of the shell structure from the multiple modal vibration regions.

[0010] In an optional embodiment of this application, the step of designating the region where the vibration amplitude of the first three modal modes is greater than a preset threshold as a modal vibration region includes: if the vibration amplitude of each order in the first region of the first three modal modes is greater than the preset threshold, the first region is designated as a modal vibration region; if the vibration amplitude of the lower order in the second region of the first three modal modes is greater than the preset threshold, and the vibration amplitude of the higher order in the second region is less than or equal to the preset threshold, the second region is designated as a modal vibration region; if the vibration amplitude of the lower order in the third region of the first three modal modes is less than or equal to the preset threshold, and the vibration amplitude of the higher order in the third region is greater than the preset threshold, the third region is not designated as a modal vibration region.

[0011] In an optional embodiment of this application, the step of determining the vibration transfer function data of each measurement point by means of a vibration sensor when each measurement point is struck includes: when each measurement point is struck by a hammer, the modal vibration response of the measurement point on the shell structure is excited; and the modal vibration response is collected by a vibration sensor as the vibration transfer function data of the measurement point.

[0012] In an optional embodiment of this application, the step of determining the overall vibration radiation energy of the shell structure based on vibration transfer function data from multiple measurement points includes: determining the overall vibration radiation energy of the shell structure based on vibration transfer function data from multiple measurement points using the following formula: Where E is the overall radiated energy of the shell structure due to vibration, and n is the number of measurement points. Let be the vibration transfer function data for the i-th measurement point.

[0013] In an optional embodiment of this application, the step of placing the housing structure on an electric drive test bench to obtain the housing radiated noise of the housing structure includes: if the overall vibration radiated energy of the housing structure is less than or equal to a preset threshold, placing the housing structure on the electric drive test bench; arranging a microphone at a target distance in the normal direction near the center region of the housing structure, and collecting the housing radiated noise of the housing structure through the microphone.

[0014] Secondly, embodiments of the present invention also provide an evaluation device for shell radiated noise. The device includes: a modal shape acquisition module for acquiring the modal shape of the shell structure; a measurement point determination module for determining multiple measurement points of the shell structure based on the modal vibration regions of the modal shape; a vibration transfer function data determination module for determining the vibration transfer function data of each measurement point by means of a vibration sensor when each measurement point is struck; and a vibration overall radiated energy determination module for determining the vibration overall radiated energy of the shell structure based on the vibration transfer function data of multiple measurement points, and determining the shell radiated noise of the shell structure based on the vibration overall radiated energy.

[0015] Thirdly, embodiments of the present invention also provide an electronic device, including a processor and a memory, wherein the memory stores computer-executable instructions that can be executed by the processor, and the processor executes the computer-executable instructions to implement the above-described method for evaluating housing radiated noise.

[0016] The embodiments of the present invention bring the following beneficial effects: This invention provides a method, apparatus, and electronic device for assessing shell radiated noise. The method involves acquiring the modal shapes of the shell structure; determining multiple measurement points on the shell structure based on the modal vibration regions of the modal shapes; determining the vibration transfer function data of each measurement point by means of a vibration sensor when each measurement point is struck; determining the overall vibration radiated energy of the shell structure based on the vibration transfer function data of multiple measurement points; and determining the shell radiated noise based on the overall vibration radiated energy. This method eliminates the need for operational testing on an electric drive test bench. By conducting impact tests on measurement points at different parts of the shell structure to obtain vibration transfer function data, and calculating multiple vibration transfer function data, the shell radiated noise level during actual operation can be effectively predicted, thereby improving the NVH performance of electric drive products and the comfort of new energy vehicles.

[0017] Other features and advantages of this disclosure will be set forth in the following description, or some features and advantages may be inferred from the description or determined without doubt, or may be learned by practicing the techniques described above.

[0018] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 A flowchart illustrating a method for evaluating radiated noise from a casing, provided as an embodiment of the present invention; Figure 2 A flowchart of another method for evaluating shell radiated noise provided in an embodiment of the present invention; Figure 3 A schematic diagram showing the distribution of the first three modes of vibration and measurement points in an electric drive rear cover shell simulation, provided for an embodiment of the present invention; Figure 4 A schematic diagram of the distribution of measurement points in a housing mechanism provided for an embodiment of the present invention; Figure 5 A schematic diagram illustrating the overall vibration radiation energy of a shell structure provided in an embodiment of the present invention; Figure 6 A schematic diagram of vibration transfer function data of shell measurement points before and after optimization, provided for an embodiment of the present invention; Figure 7 A schematic diagram illustrating the measured results of shell radiation noise at a near-field of 0.1m for optimizing the front and rear shells, as provided in an embodiment of the present invention; Figure 8 A schematic diagram of the structure of a shell-radiated noise assessment device provided in an embodiment of the present invention; Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to 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 those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Currently, existing technical solutions can predict shell noise in the time domain by collecting tangential / normal vibration signals of the shell and constructing a predictive model. Alternatively, CA simulation can be used to calculate the radiated sound power level of the shell. However, these solutions all evaluate radiated noise based on formulas or theories, lacking a benchmark against actual models and failing to accurately capture the prominence of the shell's modal noise.

[0023] Based on this, and with increasingly compressed development cycles, in order to identify electric drive NVH risks early and improve vehicle NVH performance, this invention provides a method, device, and electronic device for evaluating housing radiated noise. Specifically, it provides a method for evaluating and optimizing the modal noise of the electric drive housing, which can solve the problem that simulation or theoretical formula calculations cannot accurately and effectively evaluate the sudden changes in electric drive noise caused by modal resonance of the physical product housing, thereby improving the in-vehicle sound quality and user experience.

[0024] To facilitate understanding of this embodiment, a method for evaluating shell radiated noise disclosed in this embodiment of the invention will first be described in detail.

[0025] Example 1: This invention provides a method for evaluating the radiated noise of a casing, see [link to relevant documentation]. Figure 1 The flowchart shown illustrates a method for assessing radiated noise from a housing. This method may include the following steps: Step S102: Obtain the modal vibration modes of the shell structure.

[0026] In this embodiment, the modal modes of the shell structure can be obtained through simulation. A modal mode is a specific deformation pattern exhibited by a structure when it vibrates at a certain natural frequency. It describes the distribution pattern of relative displacement of each part of the structure during vibration.

[0027] Step S104: Determine multiple measurement points of the shell structure based on the modal vibration region of the modal mode.

[0028] In this embodiment, the shell structure can be divided into multiple measurement points according to the modal vibration region of the mode shape. In principle, this embodiment can also divide the measurement points into regions with large amplitudes of the first three mode shapes.

[0029] Step S106: When each measurement point is struck, the vibration transfer function data of each measurement point is determined by the vibration sensor.

[0030] In this embodiment, vibration sensors can be set at the locations of each measurement point. When each measurement point is struck (e.g., struck by a hammer), the vibration transfer function data of each measurement point can be determined by the vibration sensors.

[0031] Step S108: Determine the overall vibration radiation energy of the shell structure based on the vibration transfer function data of multiple measurement points, and determine the shell radiation noise of the shell structure based on the overall vibration radiation energy.

[0032] In this embodiment, the overall vibration radiation energy of the shell structure can be calculated based on vibration transfer function data from multiple measurement points (e.g., averaging, weighted calculation, etc.), and the shell radiation noise can be further evaluated. The overall vibration radiation energy of the shell structure can describe the overall abrupt change level of the shell mode's vibration.

[0033] This invention provides a method for evaluating shell radiated noise. The method involves obtaining the modal vibration modes of the shell structure; determining multiple measurement points on the shell structure based on the modal vibration regions of the modal vibration modes; determining the vibration transfer function data of each measurement point by means of a vibration sensor when each measurement point is struck; determining the overall vibration radiated energy of the shell structure based on the vibration transfer function data of multiple measurement points; and determining the shell radiated noise based on the overall vibration radiated energy. This method eliminates the need for operational testing on an electric drive test bench. By conducting impact tests on measurement points at different parts of the shell structure to obtain vibration transfer function data, and calculating multiple vibration transfer function data, the method can effectively predict the shell radiated noise level during actual operation, thereby improving the NVH performance of electric drive products and the comfort of new energy vehicles.

[0034] Example 2: This invention provides another method for evaluating housing radiated noise, based on the above embodiments, focusing on the specific implementation of evaluating the modal noise level of an electrically driven housing. See also... Figure 2 The flowchart shown represents another method for assessing casing radiated noise, which may include the following steps: Step S202: Obtain the modal vibration modes of the shell structure.

[0035] Step S204: Determine multiple measurement points of the shell structure based on the modal vibration region of the modal shape.

[0036] In some embodiments, the region where the vibration amplitude of the first three modal modes is greater than a preset threshold can be defined as the modal vibration region; multiple measurement points of the shell structure can be determined from multiple modal vibration regions.

[0037] Considering that the low-order modal vibration amplitudes and vibration regions of the shell structure are relatively large and play a major role in the radiated noise of the structural modes, this embodiment can take into account the regions with large amplitudes of the first three modal modes when determining multiple measurement points of the shell structure.

[0038] In some embodiments, if the vibration amplitude of each order in the first region of the first three modal modes is greater than a preset threshold, the first region is designated as a modal vibration region; if the vibration amplitude of the lower order in the second region of the first three modal modes is greater than a preset threshold, and the vibration amplitude of the higher order in the second region is less than or equal to a preset threshold, the second region is designated as a modal vibration region; if the vibration amplitude of the lower order in the third region of the first three modal modes is less than or equal to a preset threshold, and the vibration amplitude of the higher order in the third region is greater than a preset threshold, the third region is not designated as a modal vibration region.

[0039] For the first region, the vibration amplitude of each mode is greater than the preset threshold, so the first region can be directly regarded as the modal vibration region; for the second and third regions, the vibration amplitude of each mode is not greater than the preset threshold, so in this embodiment, the arrangement of measurement points for lower-order modes can be given priority.

[0040] In this embodiment, a second region where the amplitude of a lower-order vibration is greater than a preset threshold and the amplitude of a higher-order vibration is less than or equal to a preset threshold can be used as a modal vibration region; a third region where the amplitude of a higher-order vibration is greater than a preset threshold and the amplitude of a higher-order vibration is less than or equal to a preset threshold can not be used as a modal vibration region.

[0041] In addition, for shell structures with larger areas, the measurement points should be distributed more densely in areas with large low-order vibration mode amplitudes.

[0042] See also Figure 3 This diagram illustrates the distribution of measurement points for the first three modes of vibration of an electrically driven rear cover shell. Based on the first three modes of vibration of the electrically driven rear cover shell, some measurement points can be roughly distributed on the first mode shape. The red area on the mode shape represents the region with large vibration amplitude, with point 7 in the diagram having the largest amplitude. Measurement points must be placed in this region and should be appropriately densely packed, distributed outwards according to the amplitude level, for a total of 13 measurement points. Then, the measurement points are distributed on the second mode shape, with points 4 and 10 appropriately adjusted to be closer to the red area with large amplitude in the second mode. Similarly, the measurement points are distributed on the third mode shape, with points 5 and 9 appropriately adjusted to fall within the red area.

[0043] See also Figure 4 A schematic diagram of the distribution of measurement points for a shell mechanism is shown in Figure 4, which illustrates the specific distribution of 13 measurement points based on the first three mode shapes.

[0044] Step S206: When each measurement point is struck, the vibration transfer function data of each measurement point is determined by the vibration sensor.

[0045] In some embodiments, when each measurement point is struck by a hammer, the modal vibration response of the measurement point on the shell structure is excited; the modal vibration response is collected by a vibration sensor as the vibration transfer function data of the measurement point.

[0046] In this embodiment, each measurement point can be struck with a hammer. The hammer should be placed close to the measurement point during the strike to ensure that the modal vibration response at that point on the shell is excited. The modal vibration response can be collected using a vibration sensor as the vibration transfer function data of the measurement point.

[0047] In some embodiments, if the vibration amplitude of the vibration transfer function data at the measurement point is greater than a preset threshold, the shell structure of the measurement point is adjusted.

[0048] If the vibration amplitude of the vibration transfer function data at the measurement point exceeds a preset threshold, the vibration amplitude at that measurement point is considered too large, and the shell structure at that measurement point can be optimized. The vibration amplitude of the optimized measurement point's vibration transfer function data can be controlled within 6-10 dB. Preferably, the vibration amplitude of the optimized measurement point's vibration transfer function data can be 8 dB.

[0049] If the overall vibration radiation energy of the shell structure is less than or equal to the preset threshold (the preset threshold can be 6-10dB), the shell structure can be placed on the electric drive test bench for testing; if the overall vibration radiation energy of the shell structure is greater than the preset threshold, the shell structure needs to be further optimized, and further optimization is needed to reduce the vibration transfer function data with excessively large values ​​at the measurement points.

[0050] Step S208: Determine the overall vibration radiation energy of the shell structure based on the vibration transfer function data of multiple measurement points, and determine the shell radiation noise of the shell structure based on the overall vibration radiation energy.

[0051] In this embodiment, the shell-radiated noise of the shell structure can be calculated by weighted calculation or average calculation.

[0052] Taking average calculation as an example, in some embodiments, the overall vibration radiated energy of the shell structure can be determined based on vibration transfer function data from multiple measurement points using the following formula: Where E is the overall radiated energy of the shell structure due to vibration, and n is the number of measurement points. Let be the vibration transfer function data for the i-th measurement point.

[0053] in, This can be FPF (Frequency Response Function) data, with units of (mm / s) / N. For n measurements, the sum of the vibration energies at all measurement points on the shell structure represents the overall vibration radiation energy E.

[0054] For example, such as Figure 4 If the number of measurement points shown is n=13, then... See also Figure 5 The diagram shows the overall radiated energy of a shell structure under vibration. Figure 5 It shows Figure 4 The average calculation results of the vibration transfer function data at 13 measurement points. Among them, the maximum vibration value near the shell modal frequency of 1600Hz is 37dB(mm / s) / N, which is about 27dB compared with the background vibration. The shell vibration amplitude changes abruptly from 10dB to 37dB(mm / s) / N.

[0055] This embodiment mainly focuses on optimizing the noise of the first two shell modes. According to Figure 3 Analysis of the measured data at the measurement points on the third-order mode shape diagram shows that the main contributors to the abrupt change in the shell's modal noise are measurement points 7, 4, and 10. Optimization of the shell vibration transfer function is required for these three points.

[0056] During optimization, the first two modal array regions of the shell can be segmented and optimized by designing an outward-facing bald structure and adding internal mesh reinforcement ribs. (See also...) Figure 6 The diagram shows vibration transfer function data of the shell measurement points before and after optimization. Figure 6 The vibration transfer function data of the shell measurement points before and after optimization are shown. The shell modal frequency increased by 1600→2400Hz, the vibration amplitude increased from 37→19dB, and the overall vibration energy of the shell decreased by 18dB, showing a significant optimization effect.

[0057] Step S210: Place the housing structure on the electric drive test bench for testing to obtain the housing radiated noise of the housing structure.

[0058] In this embodiment, the housing structure can be placed on an electric drive test bench to conduct a full-system test and obtain the housing radiated noise. If the abrupt change in near-field noise at the housing mode is within 5 dB, it can be considered to have met expectations.

[0059] For example, the shell radiated noise of the shell structure before optimization is 20dB, and the shell radiated noise of the shell structure after optimization is 5dB. It can be considered that the shell modal noise level assessment and optimization design method can effectively guide the early NVH performance development and design of the shell.

[0060] In some embodiments, if the overall radiated energy of the vibration of the shell structure is less than or equal to a preset threshold, the shell structure is placed on an electric drive test bench for testing; a microphone is placed at a target distance in the normal direction near the center region of the shell structure, and the shell radiated noise of the shell structure is collected through the microphone.

[0061] In this embodiment, the near-field noise at a normal distance of 0.1m from the center point of the housing area during motor operation testing can be compared, demonstrating good agreement in evaluating the noise level of the housing's modal abrupt change. The near-field noise distance varies depending on the size and shape of the housing; in this embodiment, the microphone distance for collecting near-field noise should be sufficient to capture the overall radiated noise of the housing effectively.

[0062] During testing, a microphone can be placed at a normal distance of 0.1m (the target distance can be 0.1m) near the center of the motor housing to detect the housing's radiated noise as near-field noise. Furthermore, the near-field noise distance varies depending on the size and shape of the housing; the microphone distance for collecting near-field noise should be sufficient to capture the overall radiated noise of the housing effectively. The method provided in this embodiment of the invention has good operability and effectiveness and can be used to solve and apply engineering cases.

[0063] To verify the effectiveness of the above-mentioned assessment and optimization design method for housing modal noise, the motor bench test was conducted at the center point of the housing region ( Figure 3 A microphone was placed at a normal distance of 0.1m from measurement point 7) to collect radiated noise data from the casing. See also... Figure 7 The diagram shows the measured results of shell radiation noise at a near-field of 0.1m for an optimized front and rear shell. Figure 7 The comparison of measured near-field noise at 0.1m of the housing before and after optimization during motor bench testing is shown. Before optimization, the noise at the first housing modal frequency of 1600Hz suddenly increased to 27dB, the noise at the second housing modal frequency of 3400Hz suddenly increased to 8dB, and there was no obvious noise sudden change at the third modal frequency. In addition, after optimization, the amplitude of the housing modal noise sudden change changed from 90 to 75dB, and the noise at 0.1m of the housing decreased by 15dB. The improvement effect is very obvious. The method for evaluating and optimizing housing modal noise provided in this embodiment has good engineering guidance significance.

[0064] The method provided by this invention conducts static impact tests by dividing the housing structure into measurement points in different areas, eliminating the need for operational testing on an electric drive test bench. The vibration transfer function data obtained from all measurement points are averaged and weighted. The overall vibration radiation energy calculated by this method shows a good correlation with the housing radiation noise at 0.1m near the electric drive test bench. This method can effectively predict the housing modal radiation noise level during actual operation of the electric drive. By optimizing areas with large vibration amplitudes at measurement points, the prominence of housing modal noise can be effectively improved. This method enables the assessment and optimization of housing noise radiation levels in the electric drive assembly at the component level. Compared to traditional whole-machine testing on an electric drive test bench to identify risks, this method allows for early risk prediction and optimization, significantly improving the efficiency of electric drive NVH development, shortening product development cycles, and enhancing the NVH sound quality of the electric drive and the comfort of passengers.

[0065] Compared with existing methods for evaluating housing noise, the method provided in this embodiment has the following main advantages: 1. The method provided in this embodiment is the first to propose obtaining vibration transfer function data at different points on the shell by tapping different parts of the shell. The prominence level of the shell modal noise is obtained by averaging and weighting the data from different measurement points. Compared with the traditional method of obtaining the prominence level of the shell acoustic radiation noise through electric drive operation or simulation, this method avoids the electric drive going up and down the test bench and solves the problem of insufficient simulation accuracy caused by the large difference between the simulation boundary and the actual product. It greatly improves the development efficiency and accuracy of NVH in the early stage.

[0066] 2. The method provided in this embodiment obtains the prominence level of shell modal vibration by conducting actual measurements at measurement points and using average weighting. The results are then compared with the measured near-field noise at 0.1m. The comparison shows that the method has good accuracy and can effectively assess the radiated noise level of the shell modal. By identifying points or regions that contribute significantly to the shell modal noise, optimizing these regions and conducting further impact tests, the optimized amplitude of the vibration and noise transfer function in these regions is evaluated. Compared to traditional bench testing, this method significantly improves development efficiency and reduces the NVH development cycle.

[0067] Example 3: Corresponding to the above method embodiments, this invention provides an evaluation device for shell radiated noise, see [link to relevant documentation]. Figure 8 The diagram shows a structural schematic of a casing radiated noise assessment device, which includes: Modal mode acquisition module 81 is used to acquire the modal modes of the shell structure; The measurement point determination module 82 is used to determine multiple measurement points of the shell structure based on the modal vibration region of the mode shape; The vibration transfer function data determination module 83 is used to determine the vibration transfer function data of each measurement point by means of a vibration sensor when each measurement point is struck. The overall vibration radiation energy determination module 84 is used to determine the overall vibration radiation energy of the shell structure based on the vibration transfer function data of multiple measurement points, and to determine the shell radiation noise of the shell structure based on the overall vibration radiation energy.

[0068] This invention provides a device for evaluating shell radiated noise. The device acquires the modal vibration modes of the shell structure; determines multiple measurement points on the shell structure based on the modal vibration regions of the modal vibration modes; determines the vibration transfer function data of each measurement point by means of a vibration sensor when each measurement point is struck; determines the overall vibration radiated energy of the shell structure based on the vibration transfer function data of multiple measurement points; and determines the shell radiated noise based on the overall vibration radiated energy. This method eliminates the need for operational testing on an electric drive test bench. By conducting impact tests on measurement points at different parts of the shell structure to obtain vibration transfer function data, and calculating multiple vibration transfer function data, the device can effectively predict the shell radiated noise level during actual operation, thereby improving the NVH performance of electric drive products and the comfort of new energy vehicles.

[0069] The aforementioned device also includes a shell structure optimization module, used to adjust the shell structure of the measuring point if the vibration amplitude of the vibration transfer function data at the measuring point is greater than a preset threshold.

[0070] The aforementioned device also includes: a housing structure noise testing module, used to place the housing structure on an electric drive test bench for testing, and obtain the housing radiated noise of the housing structure.

[0071] The aforementioned measurement point determination module is used to define the regions where the vibration amplitude of the first three modal modes is greater than a preset threshold as modal vibration regions; and to determine multiple measurement points of the shell structure from multiple modal vibration regions.

[0072] The aforementioned measurement point determination module is used to designate the first region as a modal vibration region if the vibration amplitude of each order in the first region of the first three modal modes is greater than a preset threshold; to designate the second region as a modal vibration region if the vibration amplitude of the lower order in the second region of the first three modal modes is greater than a preset threshold, and the vibration amplitude of the higher order in the second region is less than or equal to a preset threshold; and not to designate the third region as a modal vibration region if the vibration amplitude of the lower order in the third region of the first three modal modes is less than or equal to a preset threshold, and the vibration amplitude of the higher order in the third region is greater than a preset threshold.

[0073] The aforementioned vibration transfer function data determination module is used to excite the modal vibration response of each measurement point on the shell structure when each measurement point is struck by a hammer; and to collect the modal vibration response as the vibration transfer function data of the measurement point through a vibration sensor.

[0074] The aforementioned overall vibration radiation energy determination module is used to determine the overall vibration radiation energy of the shell structure based on vibration transfer function data from multiple measurement points using the following formula: Where E is the overall radiated energy of the shell structure due to vibration, and n is the number of measurement points. Let be the vibration transfer function data for the i-th measurement point.

[0075] The aforementioned shell structure noise testing module is used to place the shell structure on an electric drive test bench for testing if the overall vibration radiation energy of the shell structure is less than or equal to a preset threshold; a microphone is placed at a target distance in the normal direction near the center area of ​​the shell structure to collect the shell radiation noise of the shell structure.

[0076] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the shell radiation noise assessment device described above can be referred to the corresponding process in the embodiments of the shell radiation noise assessment method described above, and will not be repeated here.

[0077] Example 4: This invention also provides an electronic device for evaluating the aforementioned method for assessing casing radiated noise; see [link to related documentation]. Figure 9 The diagram shows the structure of an electronic device, which includes a memory 100 and a processor 101. The memory 100 is used to store one or more computer instructions, which are executed by the processor 101 to implement the aforementioned method for evaluating housing radiated noise.

[0078] Furthermore, Figure 9 The electronic device shown also includes a bus 102 and a communication interface 103, with the processor 101, the communication interface 103 and the memory 100 connected via the bus 102.

[0079] The memory 100 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one communication interface 103 (which can be wired or wireless), such as the Internet, wide area network, local area network, metropolitan area network, etc. The bus 102 may be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 9 The symbol is represented by a single double-headed arrow, but this does not mean that there is only one bus or one type of bus.

[0080] Processor 101 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of processor 101 or by instructions in software form. Processor 101 can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this invention can be directly manifested as execution by a hardware decoding processor, or execution by a combination of hardware and software modules in the decoding processor. The software module can reside in a readily available storage medium in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory 100, and processor 101 reads information from memory 100 and, in conjunction with its hardware, completes the steps of the method described in the foregoing embodiments.

[0081] This invention also provides a computer-readable storage medium storing computer-executable instructions. When these computer-executable instructions are called and executed by a processor, they cause the processor to implement the aforementioned method for evaluating casing radiated noise. For specific implementation details, please refer to the method embodiments, which will not be repeated here.

[0082] The computer program products of the shell radiated noise assessment method, apparatus and electronic device provided in the embodiments of the present invention include a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the methods in the preceding method embodiments. For specific implementation, please refer to the method embodiments, which will not be repeated here.

[0083] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system and / or device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0084] Furthermore, in the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0085] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0086] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0087] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for evaluating the radiated noise of a casing, characterized in that, The method includes: Obtain the modal shapes of the shell structure; Multiple measurement points of the shell structure are determined based on the modal vibration region of the modal shape; When each of the measurement points is struck, the vibration transfer function data of each of the measurement points is determined by a vibration sensor. The overall vibration radiation energy of the shell structure is determined based on the vibration transfer function data of multiple measurement points, and the shell radiation noise of the shell structure is determined based on the overall vibration radiation energy.

2. The method according to claim 1, characterized in that, After determining the vibration transfer function data of each measurement point using a vibration sensor, the method further includes: If the vibration amplitude of the vibration transfer function data at the measurement point is greater than a preset threshold, the shell structure of the measurement point is adjusted.

3. The method according to claim 1, characterized in that, The method further includes: The housing structure was placed on an electric drive test bench for testing, and the housing radiation noise of the housing structure was obtained.

4. The method according to claim 1, characterized in that, The step of determining multiple measurement points of the shell structure based on the modal vibration region of the modal shape includes: The regions where the vibration amplitude of the first three modes is greater than a preset threshold are defined as the modal vibration regions. Multiple measurement points of the shell structure are determined from multiple modal vibration regions.

5. The method according to claim 4, characterized in that, The step of defining the region where the vibration amplitude of the first three modal modes is greater than a preset threshold as the modal vibration region includes: If the vibration amplitude of each order in the first region of the first three modes is greater than a preset threshold, the first region is regarded as the modal vibration region. If the vibration amplitude of the lower order in the second region of the first three modal vibration modes is greater than a preset threshold, and the vibration amplitude of the higher order in the second region is less than or equal to the preset threshold, the second region is regarded as a modal vibration region. If the vibration amplitude of the lower order of the third region of the first three modal vibration modes is less than or equal to a preset threshold, and the vibration amplitude of the higher order of the third region is greater than the preset threshold, the third region is not considered as a modal vibration region.

6. The method according to claim 1, characterized in that, The step of determining the vibration transfer function data of each of the measurement points by means of a vibration sensor when each of the measurement points is struck includes: When each of the measurement points is struck by a hammer, the modal vibration response of the measurement points on the shell structure is excited; The modal vibration response is collected by a vibration sensor as the vibration transfer function data of the measurement point.

7. The method according to claim 1, characterized in that, The step of determining the overall vibration radiated energy of the shell structure based on vibration transfer function data from multiple measurement points includes: The overall vibrational radiated energy of the shell structure is determined based on the vibration transfer function data from multiple measurement points using the following formula: Where E is the overall radiated energy of the shell structure due to vibration, and n is the number of measurement points. The vibration transfer function data for the i-th measurement point.

8. The method according to claim 3, characterized in that, The step of placing the housing structure on an electric drive test bench to test and obtain the housing radiated noise of the housing structure includes: If the overall vibration radiation energy of the shell structure is less than or equal to a preset threshold, the shell structure is placed on an electric drive test bench for testing. A microphone is placed at a target distance normal to the center region of the shell structure to collect the shell-radiated noise of the shell structure.

9. A device for evaluating the radiated noise of a housing, characterized in that, The device includes: The modal shape acquisition module is used to acquire the modal shapes of the shell structure. The measurement point determination module is used to determine multiple measurement points of the shell structure based on the modal vibration region of the modal mode. The vibration transfer function data determination module is used to determine the vibration transfer function data of each of the measurement points by means of a vibration sensor when each of the measurement points is struck. The overall vibration radiation energy determination module is used to determine the overall vibration radiation energy of the shell structure based on the vibration transfer function data of multiple measurement points, and to determine the shell radiation noise of the shell structure based on the overall vibration radiation energy.

10. An electronic device, characterized in that, It includes a processor and a memory, the memory storing computer-executable instructions that can be executed by the processor, the processor executing the computer-executable instructions to implement the method for evaluating housing radiated noise as described in any one of claims 1 to 8.

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