An acoustic pressure test method, device, equipment and computer storage medium

Abstract

Embodiments of the present application disclose a sound pressure test method, comprising: determining a target corresponding relationship of a target power component in an electric drive system of a vehicle based on a target order of the target power component, the target corresponding relationship being a corresponding relationship between a frequency and a critical value of a sound pressure level; performing a sound pressure test on the target power component based on the target corresponding relationship; and determining whether the target power component passes the sound pressure test. Embodiments of the present application also provide a sound pressure test device, equipment and a computer storage medium.

Description

Technical Field

[0001] This invention relates to automotive sound pressure testing technology, and more particularly to a sound pressure testing method, apparatus, equipment, and computing storage medium. Background Technology

[0002] The electrification of vehicle models in the automotive industry (e.g., pure electric vehicles (EVs) and hybrid electric vehicles (HEVs)) has accelerated significantly, the penetration rate of new energy vehicles in the market has increased substantially, customers' demand for vehicle comfort has increased significantly, and their attention to vehicle noise (N), vibration (V), and harshness (H) remains high.

[0003] Among them, new energy vehicles have introduced electric motors into their power systems. The whine of the electric motor itself and the whine of the reducer gears caused by the high-speed operation of the motor have become the main NVH problems of hybrid vehicles. The electromagnetic noise of the motor is the main source of motor noise, which is caused by the alternating electromagnetic force generated by the air gap magnetic field acting on the stator and rotor of the motor, and exhibits obvious order characteristics. New energy vehicles aggravate the whine problem of the reducer gears. Gear whine is a noise with order characteristics generated by the load-bearing gear pair under the excitation of dynamic transmission error.

[0004] Whistling noise is easily identifiable and severely impacts the customer's driving experience. With increasing competition in the vehicle market, the development of NVH (Noise, Vibration, and Harshness) in electric drive systems is crucial. However, existing vehicle sound pressure level testing methods cannot be used as a basis for determining whether a vehicle's sound pressure level meets standards. This demonstrates that current sound pressure level testing methods for vehicle power components suffer from low testing efficiency. Summary of the Invention

[0005] This invention provides a sound pressure testing method, apparatus, device, and computer storage medium, which can improve the testing efficiency of sound pressure testing methods for vehicle power components.

[0006] The technical solution of this invention is implemented as follows:

[0007] This invention provides a sound pressure level testing method, comprising:

[0008] Based on the target order of the target power component in the vehicle's electric drive system, the target correspondence of the target power component is determined; wherein, the target correspondence is the correspondence between the frequency and the critical value of the sound pressure level;

[0009] Based on the target correspondence, a sound pressure test is performed on the target power component to determine whether the target power component passes the sound pressure test.

[0010] This invention provides a sound pressure testing device, comprising:

[0011] A determination module is used to determine the target correspondence of the target power component based on the target order of the target power component in the electric drive system of the vehicle; wherein the target correspondence is the relationship between the frequency and the critical value of the sound pressure level.

[0012] The testing module is used to perform a sound pressure test on the target power component based on the target correspondence, and to determine whether the target power component passes the sound pressure test.

[0013] This invention provides a sound pressure level testing device, including: a processor and a storage medium storing executable instructions of the processor. The storage medium performs operations dependent on the processor via a communication bus. When the instructions are executed by the processor, the sound pressure level testing method described in one or more of the above embodiments is executed.

[0014] This invention provides a computer storage medium storing executable instructions. When the executable instructions are executed by one or more processors, the processors execute the sound pressure testing method as described in one or more embodiments.

[0015] The beneficial effects of this invention are:

[0016] (1) By determining the target order of the target power component, the correspondence between the frequency and the critical value of the sound pressure level is determined. The target correspondence is made closer to the actual environment. In this way, a reasonable target correspondence is formulated. Based on the reasonable target correspondence, the test results of whether the sound pressure test is passed are more accurate.

[0017] (2) In the sound pressure test of the target power component, the target correspondence is used as the basis to determine whether the target power component passes the sound pressure test, which improves the test efficiency of the sound pressure test of the vehicle's power component and thus meets the sound pressure requirements of the vehicle. Attached Figure Description

[0018] Figure 1 A schematic flowchart of an optional sound pressure testing method provided in an embodiment of the present invention;

[0019] Figure 2 A flowchart illustrating an example of an optional sound pressure testing method provided in an embodiment of the present invention;

[0020] Figure 3 A schematic diagram of an optional in-vehicle background sound pressure level curve provided for an embodiment of the present invention;

[0021] Figure 4A schematic diagram of an optional in-vehicle sound insulation curve provided for an embodiment of the present invention;

[0022] Figure 5 A schematic diagram of an optional electric drive assembly order noise target curve provided for an embodiment of the present invention;

[0023] Figure 6 A schematic diagram of an optional sound pressure testing device provided in an embodiment of the present invention;

[0024] Figure 7 This is a schematic diagram of an optional sound pressure testing device provided in an embodiment of the present invention. Detailed Implementation

[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0026] This invention provides a sound pressure testing method. Figure 1 A schematic flowchart of an optional sound pressure testing method provided in an embodiment of the present invention is shown below. Figure 1 As shown, the sound pressure testing method may include:

[0027] S101: Determine the target correspondence of the target power components based on the target order of the target power components in the vehicle's electric drive system;

[0028] S102: Perform sound pressure test on the target power component based on the target correspondence to determine whether the target power component passes the sound pressure test.

[0029] In related technologies, for motor NVH testing, the main approach is to improve the testing efficiency by modifying the structure of the testing system. However, the vehicle sound pressure testing methods in these technologies cannot be used as a basis for determining whether a vehicle's sound pressure meets the standards. Often, the test results are substandard, but the vehicle meets the overall NVH acceptance targets after installation. This shows that the existing vehicle sound pressure testing methods suffer from low testing efficiency.

[0030] In order to improve the testing efficiency of sound pressure testing of vehicle power components, in this embodiment of the invention, the sound pressure testing equipment determines the power components that need to be tested in the electric drive system of the vehicle, i.e., the target power components. For example, the target power components can be motors or reducers, etc. Here, this embodiment of the invention does not make specific limitations on this.

[0031] After determining the target power component, the target order of the target power component can be determined. The calculation method of the target order is different for different target power components. For example, when the target power component is a motor, the electromagnetic force frequency order can be used as the target order. When the target power component is a reducer, the gear meshing order of the reducer can be used as the target order. Here, the embodiments of the present invention do not make specific limitations on this.

[0032] After determining the target order of the target power component, the target correspondence of the target power component can be determined based on the target order of the target power component. The target correspondence is the correspondence between frequency and critical value of sound pressure level. In this way, the critical value of sound pressure level of the target power component in the test can be known at each frequency.

[0033] It should be noted that different target orders correspond to different target relationships, that is, different relationships between frequencies and critical values ​​of sound pressure level. In this way, from the target relationship, we can know the critical values ​​of sound pressure level that the target power component can achieve at different frequencies during the test. Whether the target power component passes the sound pressure test is determined by whether it is greater than the critical value of sound pressure level.

[0034] The aforementioned target correspondence can be represented by a curve in a rectangular coordinate system, with the horizontal axis representing frequency and the vertical axis representing sound pressure level. Each type of power component corresponds to a curve. For example, a motor corresponds to a curve in a rectangular coordinate system, and the correspondence of this curve is the target correspondence. A reducer corresponds to a curve in a rectangular coordinate system, and the correspondence of this curve is the target correspondence.

[0035] After understanding the above target correspondence, the sound pressure testing equipment performs a sound pressure test on the target power component to obtain the correspondence between the test frequency and the sound pressure level. This correspondence is then compared with the target correspondence. If there are multiple test frequencies, and the sound pressure level corresponding to each test frequency is less than or equal to the critical value of the sound pressure level corresponding to each test frequency in the target correspondence, the sound pressure test of the target power component is determined to be passed. If at least one of the sound pressure levels corresponding to the test frequency is greater than the critical value of the sound pressure level corresponding to the test frequency in the target correspondence, the sound pressure test of the target power component is determined to be failed.

[0036] Alternatively, if the proportion of sound pressure levels at the test frequency that are less than or equal to the critical value of the sound pressure level at the test frequency in the target correspondence is greater than a preset proportion, the sound pressure test of the target power component is determined to have passed. If the proportion of sound pressure levels at the test frequency that are less than or equal to the critical value of the sound pressure level at the test frequency in the target correspondence is less than or equal to a preset proportion, the sound pressure test of the target power component is determined to have failed. Of course, other determination methods may also be included, but this embodiment of the invention does not specifically limit them.

[0037] Additionally, it should be noted that, taking the motor as an example, the above-mentioned method for testing the sound pressure of the target power component involves first controlling the cylinder mechanism to reliably contact the motor housing with the acceleration sensor, controlling the motor to run at a speed of 1000 RPM, and controlling the data acquisition unit to simultaneously acquire acceleration, speed, and noise sensor signals at a sampling rate of 20 kHz. The data is then analyzed using Fast Fourier Transform (FFT) to calculate the test results. Of course, the above-mentioned method for testing the sound pressure of the target power component can also employ other methods. There can be one, two, or more sound pressure testing methods. Here, this embodiment of the invention does not specifically limit this.

[0038] Before S101, it is necessary to determine the target order of the target power component. Therefore, in order to calculate the target order of the target power component, we will explain it here by taking a motor or a reducer as examples:

[0039] In an optional embodiment, the above method further includes:

[0040] When the target power component is a motor, the electromagnetic force frequency order corresponding to the motor spatial module being 0 is determined as the target order.

[0041] Understandably, when the target power component is an electric motor, the target order can be calculated using the following formula (1):

[0042] When U=2np±3δaC=0, γ=2np(1)

[0043] Where n, C = 0, 1, 2, ..., U is the spatial module, γ is the order, p is the number of pole pairs of the motor, δ = 1 when the winding is a symmetrical non-equiphase winding, δ = 2 when it is an equiphase winding, and a is the number of unit motors. The calculation formulas for unit motors are obtained from the following formulas (2) and (3):

[0044] Single-layer winding a = GCD(p,N) (2)

[0045] Where N / GCD(p,N) is even, a = GCD(p,N); when N / GCD(p,N) is odd, a = GCD(p,N) / 2. The above GCD is the greatest common divisor operation, N is the number of motor slots. When the number of slots N / a of a unit motor is divisible by 3, it is a non-equiphase winding; when the number of slots N / a of a unit motor is divisible by 6, it is an equiphase winding.

[0046] Thus, by substituting the results of formulas (2) and (3) into formula (1) with the spatial modulus equal to 0, the order of the motor can be calculated, which is the target order mentioned above.

[0047] In an optional embodiment, the above method further includes:

[0048] When the target power component is a speed reducer, the gear meshing order of the speed reducer is determined as the target order.

[0049] Understandably, when the target power component is a reducer, the gear meshing order of the reducer is calculated according to formula (4):

[0050]

[0051] In the formula, γ is the order, n1 is the reference shaft speed, R is the transmission ratio of the current shaft relative to the reference shaft, and Z is the number of teeth on the gear on the current shaft. The calculated γ is the target order mentioned above.

[0052] In this way, the gear meshing order of the reducer, i.e. the target order, can be calculated.

[0053] In order to obtain a reasonable target correspondence for the target power components, in an optional embodiment, S101 may include:

[0054] Obtain the first and second test relationships for at least two vehicle models;

[0055] Extract the test relations under the target order from the first test relation to obtain the third test relation;

[0056] Based on the third test relationship, the sound pressure level at the preset frequency interval is extracted;

[0057] Based on the second test relationship, the sound insulation amount at the preset frequency interval points is extracted;

[0058] The background noise of the target order sound source at the preset frequency interval is determined by using the sound pressure level at the preset frequency interval and the sound insulation at the preset frequency interval.

[0059] Based on the preset frequency interval points and the target order sound source background noise at the preset frequency interval points, curve fitting is performed to obtain the target correspondence.

[0060] Understandably, the sound pressure testing equipment first acquires a sample, which may include vehicles of at least two different models. Each model may include one or more vehicles. This embodiment of the invention does not specifically limit this.

[0061] Furthermore, by testing each vehicle model using this sample, a first test relationship and a second test relationship can be obtained. The first test relationship is the test relationship between engine speed and sound pressure level; the second test relationship is the test relationship between frequency and sound insulation. In other words, by testing each vehicle in the sample, the test relationship between engine speed and sound pressure level and the test relationship between frequency and sound insulation can be obtained.

[0062] It should be noted that the first test relationship includes the first test relationship for each vehicle model, and similarly, the second test relationship includes the second test relationship for each vehicle model.

[0063] Additionally, it should be noted that the test condition for obtaining the aforementioned first test relationship is the vehicle coasting condition. This is to eliminate the additional noise introduced by the electric drive system, thereby obtaining the noise result at the driver's right ear across the entire speed range, which constitutes the first test relationship. The first test relationship can include the first test relationship for each vehicle model. When the vehicle models in the sample include A, B, and C, the first test relationship includes: the first test relationship for vehicle model A, the first test relationship for vehicle model B, and the first test relationship for vehicle model C.

[0064] The second test relationship is the sound insulation test conducted according to industry standards from the engine compartment to the vehicle interior. This yields the sound insulation curve from the engine compartment to the vehicle interior, i.e., the frequency versus sound insulation curve, which is the second test relationship mentioned above. The second test relationship can include the second test relationship for each vehicle model. When the vehicle models in the sample include A, B, and C, the second test relationship includes: the second test relationship for vehicle model A, the second test relationship for vehicle model B, and the second test relationship for vehicle model C.

[0065] After obtaining the first and second test relationships, it is necessary to extract the test relationship under the target order from the first test relationship to obtain the third test relationship. The third test relationship is the correspondence between rotational speed and sound pressure level under the target order. This third test relationship can include the third test relationship for each vehicle model. When the vehicle models in the sample include A, B, and C, the third test relationship includes: the third test relationship for vehicle model A, the third test relationship for vehicle model B, and the third test relationship for vehicle model C.

[0066] Then, the sound pressure level at the preset frequency interval is extracted based on the third test relationship, and the sound insulation at the preset frequency interval is extracted based on the second test relationship. In this way, the sound pressure level and sound insulation at the preset frequency interval can be known. The preset frequency interval can be set in advance according to the test specifications, or it can be determined according to the length of the frequency range in the second and third test relationships, or it can be set according to the actual test requirements. Here, the embodiments of the present invention do not make specific limitations on this.

[0067] Furthermore, the sound pressure level and sound insulation of the preset frequency interval points extracted above are both a set of values, extracted from the sound pressure level and sound insulation of the preset frequency interval points under different vehicle models. For example, when the vehicle models in the sample include A, B, and C, the sound pressure level of the preset frequency interval points is obtained from the sound pressure level of the preset frequency interval points of vehicle model A, vehicle model B, and vehicle model C; the sound pressure level of the preset frequency interval points is obtained from the sound insulation of the preset frequency interval points of vehicle model A, vehicle model B, and vehicle model C.

[0068] Among them, the sound pressure level and sound insulation of the preset frequency interval points extracted above are both discrete points.

[0069] Based on the sound pressure level and sound insulation of the preset frequency interval points extracted above, the target order sound source background noise at the preset frequency interval points can be calculated using the preset order sound source background noise calculation formula. Since the target order sound source background noise at the preset frequency interval points corresponds one-to-one with the preset frequency interval points, the target correspondence can be derived to determine whether the target power component passes the sound pressure test.

[0070] Furthermore, in order to determine the sound pressure level at the preset frequency interval, in an optional embodiment, the sound pressure level at the preset frequency interval is extracted based on a third test relationship, including:

[0071] The rotational speed in the third test relationship is transformed in the frequency domain to obtain the fourth test relationship;

[0072] From the fourth test relationship, extract the sound pressure level of at least two vehicle models at preset frequency intervals;

[0073] From the sound pressure levels of at least two vehicle models at preset frequency intervals, select the minimum value among all sound pressure levels corresponding to each frequency interval to obtain the sound pressure level at the preset frequency interval.

[0074] Understandably, since the third test relationship is the test relationship between rotational speed and sound pressure level, it is necessary to perform frequency domain conversion on the rotational speed to obtain the test relationship between frequency and sound pressure level, i.e., the fourth test relationship. The fourth test relationship is the test relationship between frequency and sound pressure level. Then, the sound pressure level of at least two vehicle models at preset frequency intervals can be extracted from the fourth test relationship. Taking vehicle models A, B, and C as an example, the sound pressure level of at least two vehicle models at preset frequency intervals can include: the sound pressure level of vehicle model A at preset frequency intervals, the sound pressure level of vehicle model B at preset frequency intervals, and the sound pressure level of vehicle model C at preset frequency intervals.

[0075] Since each frequency interval corresponds to a different vehicle model's sound pressure level, in order to obtain the sound pressure level at the preset frequency interval, the minimum value is selected from the sound pressure levels of different vehicle models at each frequency interval. This allows us to select the sound pressure level at each frequency interval and obtain the sound pressure level at the preset frequency interval, which is a discrete point.

[0076] In addition, to determine the sound insulation at preset frequency intervals, in one optional embodiment, the sound insulation at preset frequency intervals is extracted based on a second test relationship, including:

[0077] From the second test relationship, extract the sound insulation of at least two vehicle models at preset frequency intervals;

[0078] From the sound insulation values ​​of at least two vehicle models at preset frequency intervals, select the minimum value among all the sound insulation values ​​corresponding to each frequency interval to obtain the sound insulation value at the preset frequency interval.

[0079] Understandably, after obtaining the second test relationship, the sound insulation of at least two vehicle models at preset frequency intervals is extracted from the second test relationship. Taking vehicle models A, B, and C as an example, the sound insulation of at least two vehicle models at preset frequency intervals can include: the sound insulation of vehicle model A at preset frequency intervals, the sound insulation of vehicle model B at preset frequency intervals, and the sound insulation of vehicle model C at preset frequency intervals.

[0080] Since there are different sound insulation values ​​for different car models at each frequency interval, in order to obtain the sound insulation value at the preset frequency interval, the minimum value is selected from the sound insulation values ​​of different car models at each frequency interval. This allows us to select the sound insulation value at each frequency interval and obtain the sound insulation value at the preset frequency interval, which is a discrete point.

[0081] After extracting the sound pressure level and sound insulation at preset frequency intervals, in order to determine the background noise of the target order sound source at the preset frequency intervals, in an optional embodiment, the background noise of the target order sound source at the preset frequency intervals is determined using the sound pressure level and sound insulation at the preset frequency intervals, including:

[0082] Substitute the sound pressure level and sound insulation at the preset frequency intervals into the preset order sound source background noise calculation formula to obtain the target order sound source background noise at the preset frequency intervals.

[0083] Understandably, here, the sound pressure level at the preset frequency interval and the sound insulation at the preset frequency interval can be substituted into the preset order sound source background noise calculation formula. The preset order sound source background noise calculation formula is determined based on the expression of the difference between the sound power level of the point sound source and the sound pressure level of the receiving point, so that the target order sound source background noise at the preset frequency interval can be calculated.

[0084] The preset formula for calculating background noise from sound sources is as follows:

[0085]

[0086] In the formula, SPL1 represents the sound pressure level of the noise response, SPL2 represents the sound pressure level of the noise source, NR represents the sound insulation of the whole vehicle, r represents the test distance of the sound pressure level of the noise source, S represents the sound pressure level, and (4πr) 2 ρ represents the spherical surface area representing the reference radius of the sound source opening, and ρ represents the air density.

[0087] Substituting the test condition values ​​into the above formula (5), the preset calculation formulas for background noise of each order of sound source are simplified, resulting in the following formula:

[0088] M = S + NR - 5.9 (6)

[0089] Where M represents the background noise of the target order sound source.

[0090] Furthermore, in order to obtain the target correspondence for determining whether the sound pressure test is passed, in an optional embodiment, curve fitting is performed based on preset frequency intervals and the background noise of the target order sound source at the preset frequency intervals to obtain the target correspondence, including:

[0091] The sum of the background noise of the target order sound source and the prominence of the target order pure tone at the preset frequency interval is determined as the target noise target value of the target power component at the preset frequency interval.

[0092] Curve fitting is performed on the noise target values ​​of the target power components at frequency intervals and preset frequency intervals to obtain the target correspondence.

[0093] Understandably, here, after obtaining the preset frequency interval points and the background noise of the target order sound source at the preset frequency interval points, in order to improve the rationality of the target correspondence and improve the testing efficiency, the concept of the target order pure tone prominence X is added to correct the background noise of the target order sound source at the preset frequency interval points, thereby obtaining the noise target value T of the target power component at the preset frequency interval points. The noise target value T of the target power component at the preset frequency interval points can be calculated using the following formula (7):

[0094] T = M + X (7)

[0095] In this way, the target noise value of the target power component at the preset frequency interval can be calculated. By performing curve fitting on the target noise value of the target power component at the frequency interval and the preset frequency interval, the target curve can be obtained. The correspondence on the target curve is the target correspondence.

[0096] In this way, the target correspondence can be obtained, and the target correspondence can be used to determine whether the target power component has passed the sound pressure test.

[0097] Regarding S102, in order to determine whether the target power component passes the sound pressure test, in an optional embodiment, S102 may include:

[0098] When the sound pressure test value of the target power component at the preset frequency is less than or equal to the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, the target power component is determined to have passed the sound pressure test.

[0099] When the sound pressure test value of the target power component at the preset frequency is greater than the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, it is determined that the target power component fails the sound pressure test.

[0100] Understandably, after determining the target correspondence and obtaining the test results of the target power component, the test results include the sound pressure test value of the target power component at a preset frequency. The sound pressure test value at the preset frequency can be one or multiple. In the case of one, if the sound pressure test value of the target power component at the preset frequency is less than or equal to the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, the target power component is determined to have passed the sound pressure test. If the sound pressure test value of the target power component at the preset frequency is greater than the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, the target power component is determined to have failed the sound pressure test.

[0101] For two or more scenarios, if all the sound pressure test values ​​of the target power component at the preset frequency are less than or equal to the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, the target power component is determined to pass the sound pressure test. If at least one of the sound pressure test values ​​of the target power component at the preset frequency is greater than the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, the target power component is determined to fail the sound pressure test.

[0102] Of course, other rules can be set to determine whether a target power component passes the sound pressure test based on the target correspondence. Here, this embodiment of the invention does not specifically limit this.

[0103] The following examples illustrate the sound pressure testing methods in one or more of the above embodiments.

[0104] This example provides a method for setting order noise targets for the electric drive assembly (equivalent to the aforementioned electric drive system) of new energy vehicles based on the principle of sound insulation. This method is applicable to the NVH development, design, and acceptance evaluation of the electric drive assembly of new energy vehicles. Figure 2 A flowchart illustrating an example of an optional sound pressure testing method provided in an embodiment of the present invention is shown below. Figure 2 As shown, the sound pressure testing method may include:

[0105] S201: Select a certain sample size of target vehicle models for in-vehicle noise testing;

[0106] Specifically, the sample size is determined based on the size classification of the target vehicle models to which the electric drive system is planned to be installed. The sample size of the target vehicle models can be defined as A, B, C, etc. The test condition is the whole vehicle coasting condition, the purpose of which is to eliminate the additional noise introduced by the power system operation. The test results of the noise at the driver's right ear in the vehicle across the entire speed range are the first test relationship mentioned above.

[0107] S202: Calculate the electromagnetic force frequency order when the spatial module of the electric drive assembly motor is 0 and calculate the gear meshing order of the reducer.

[0108] Based on the above formulas (1) and (2), the electromagnetic force frequency order when the motor spatial module is 0 is calculated to obtain the motor order. The gear meshing order is calculated according to formula (3), which is the order of the reducer.

[0109] S203: Extract the background sound pressure level noise curves for each order inside the vehicle from the noise results (equivalent to the third test relationship mentioned above);

[0110] Furthermore, the in-vehicle background noise curves for the electromagnetic force order and gear meshing order of the motor described in S203 are extracted by using professional acoustic post-processing software to extract the speed-sound pressure level curves from the noise results at the driver's right ear in the full speed range described in S201. The aforementioned orders include: electromagnetic force order and gear meshing order of the reducer. The extracted speed-sound pressure level curves include: the speed-sound pressure level curve corresponding to the electromagnetic force order and the speed-sound pressure level curve corresponding to the gear meshing order of the reducer. Figure 3 A schematic diagram of optional background sound pressure level noise curves at various orders inside a vehicle, provided as an embodiment of the present invention, is shown below. Figure 3 As shown, the dark curve and the light line represent the speed-sound pressure level curves of different orders.

[0111] S204: The rotational speed of the background sound pressure level noise curves of each order in the vehicle is converted into the frequency domain to obtain the frequency-sound pressure level curves of each order in the vehicle (equivalent to the fourth test relationship mentioned above). The sound pressure level values ​​S(f1), S(f2), S(f3)... are extracted from the frequency-sound pressure level curves of each order in the vehicle according to the frequency interval points f1, f2, f3...

[0112] The frequency interval is determined based on the amount of data processing and testing specifications. The specific method for extracting the sound pressure level values ​​S(f1), S(f2), S(f3), etc., from the frequency-sound pressure level curves at each order within the vehicle is as follows: Select the minimum sound pressure level of all vehicle models at each frequency interval point to obtain the sound pressure level value S = min(Sf1). A (f1), S B (f1), S C (f1)……), thus, the most stringent set of discrete points S1, S2, S3…… for each order of background noise in the vehicle can be obtained (equivalent to the sound pressure level of at least two vehicle models at the preset frequency intervals mentioned above), ensuring that the target curve can cover all target vehicle models.

[0113] S205: Conduct a sound insulation test from the engine compartment to the vehicle interior to obtain the sound insulation curve from the engine compartment to the vehicle interior;

[0114] Among them, the sound insulation curve inside the vehicle is a frequency-sound insulation curve (equivalent to the second test relationship mentioned above); Figure 4 A schematic diagram of an optional in-vehicle sound insulation curve provided in an embodiment of the present invention, as shown below. Figure 4 As shown, the sound insulation curves from the cabin to the vehicle interior are frequency-sound insulation curves.

[0115] S206: Extract the sound insulation values ​​NR(f1), NR(f2), NR(f3)... from the frequency-sound insulation curve according to the same frequency points f1, f2, f3... in S204.

[0116] The specific method of S206 is as follows: Select the minimum sound insulation value of all vehicle models at each frequency interval point to obtain the sound insulation value NR = min(NR). A (f1), NR B (f1), NR C (f1)……), thus obtaining the most stringent set of sound insulation discrete points NR1, NR2, NR3…… (equivalent to the sound insulation at the preset frequency intervals mentioned above), which also ensures that the target curve can cover all target models.

[0117] S207: Based on the expression of the difference between the sound power level of the point sound source and the sound pressure level of the receiving point, the derivation formula of the sound insulation theory is derived. Substituting the test condition values ​​into the derivation formula, the calculation formula of the background noise of each order of sound source based on the sound insulation principle of the whole vehicle is obtained.

[0118] Among them, the calculation formula for background noise of each order sound source is the above formula (6). According to the calculation formula, a set of discrete points M1, M2, M3... of background noise values ​​of each order sound source distributed according to frequencies f1, f2, f3... are obtained (equivalent to the target order sound source background noise at the preset frequency interval points).

[0119] S208: Introduce the pure tone prominence value X of each order, calculate the order noise target of the electric drive assembly according to the above formula (7), and obtain a set of order sound source target noise value discrete points T1, T2, T3... distributed according to frequency f1, f2, f3... (equivalent to the target noise target value of the target power component at the above preset frequency interval).

[0120] Among them, the pure tone prominence value X of each order is the sound pressure level value of the order sound that is higher than the background sound when the subjective evaluation score of the whole vehicle for each order sound is the target score, which is extracted from the accumulated test database.

[0121] S209: Perform curve fitting on the discrete points T1, T2, T3... of the target noise values ​​of a set of order sound sources distributed according to frequencies f1, f2, f3...

[0122] In this process, a table tool is used to perform curve fitting on the discrete points T1, T2, T3... of the target noise values ​​of a set of sound sources distributed according to frequencies f1, f2, f3... Different functions are selected for curve fitting, and the goodness-of-fit R² value is given during the fitting process. An R² close to 1 indicates that the fitted curve can characterize the distribution features of all discrete points, thus obtaining a smooth curve in the target frequency domain. Figure 5 A schematic diagram of an optional electric drive assembly order noise target curve provided for an embodiment of the present invention, as shown below. Figure 5 As shown, this is the target curve of the first-order sound pressure level of the electric drive assembly at 1m.

[0123] In summary, this example provides a method for setting order noise targets for the electric drive assembly of new energy vehicles based on the principle of whole-vehicle sound insulation. This method allows for the establishment of reasonable NVH targets in the early stages of electric drive assembly product design and development, enabling the development of appropriate NVH control strategies and technical solutions during the design and development process. It also facilitates acceptance testing of the electric drive assembly's NVH development during the development process, ensuring that the electric drive assembly product is free from order-related NVH issues such as howling noise after market launch. This eliminates the difficulty in controlling howling noise risks in the later stages of project development, improving the customer's driving experience. While ensuring good NVH quality of the electric drive assembly, this method significantly reduces the development cost and shortens the development cycle of the motor assembly. It has significant application value in the field of automotive NVH technology, playing a crucial role in safeguarding NVH development during the electric drive assembly process. It avoids the problems of high development costs and long development cycles caused by overly strict target settings, and also avoids the risk of howling noise after product launch leading to customer complaints and reduced product competitiveness due to overly lenient target settings.

[0124] Through verification of the electric drive assembly project, the order noise target of the electric drive assembly formulated in this example has effectively solved the contradiction that the original electric drive assembly project failed to meet the NVH standards in individual tests, but could meet the NVH acceptance targets of the whole vehicle after being installed in the vehicle. This has shortened the development and rectification cycle and reduced costs.

[0125] This invention provides a sound pressure level (SPL) testing method, comprising: determining a target correspondence between a target power component in a vehicle's electric drive system based on the target order of that component; the target correspondence being the correspondence between frequency and a critical value of sound pressure level; performing a SPL test on the target power component based on the target correspondence; and determining whether the target power component passes the SPL test. In other words, in this invention, the correspondence between frequency and critical value of sound pressure level is determined by the target order of the target power component. This target correspondence makes the SPL more closely resemble the actual environment, thus establishing a reasonable target correspondence. Therefore, in the SPL test of the target power component, the SPL is used as the basis for determining whether the target power component passes the SPL test. The more accurate the test result based on the reasonable target correspondence, the more efficient the SPL test of the vehicle's power components becomes, thereby meeting the vehicle's SPL requirements.

[0126] Based on the same inventive concept as the foregoing embodiments, this embodiment of the invention provides a sound pressure testing device. Figure 6 A schematic diagram of an optional sound pressure testing device provided in an embodiment of the present invention is shown below. Figure 6 As shown, the sound pressure testing device includes:

[0127] The determination module 61 is used to determine the target correspondence of the target power component based on the target order of the target power component in the electric drive system of the vehicle; wherein, the target correspondence is the relationship between the frequency and the critical value of the sound pressure level.

[0128] Test module 62 is used to perform sound pressure tests on the target power component based on the target correspondence, and to determine whether the target power component passes the sound pressure test.

[0129] In an optional embodiment, the device is further used for:

[0130] When the target power component is a motor, the electromagnetic force frequency order corresponding to the motor spatial module being 0 is determined as the target order.

[0131] In an optional embodiment, the device is further used for:

[0132] When the target power component is a speed reducer, the gear meshing order of the speed reducer is determined as the target order.

[0133] In an optional embodiment, the determining module 61 is specifically used for:

[0134] Obtain a first test relationship and a second test relationship for at least two vehicle models; wherein, the first test relationship is the test relationship between engine speed and sound pressure level; the second test relationship is the test relationship between frequency and sound insulation; extract the test relationship under the target order from the first test relationship to obtain a third test relationship; based on the third test relationship, extract the sound pressure level at a preset frequency interval; based on the second test relationship, extract the sound insulation at the preset frequency interval; using the sound pressure level and the sound insulation at the preset frequency interval, determine the background noise of the target order sound source at the preset frequency interval; perform curve fitting based on the preset frequency interval and the background noise of the target order sound source at the preset frequency interval to obtain the target correspondence relationship.

[0135] In an optional embodiment, the determining module 61 extracts the sound pressure level at preset frequency intervals based on a third test relationship, including:

[0136] The rotational speed in the third test relationship is transformed in the frequency domain to obtain the fourth test relationship; the fourth test relationship is the test relationship between frequency and sound pressure level; from the fourth test relationship, the sound pressure level of at least two vehicle models at preset frequency intervals is extracted; from the sound pressure levels of at least two vehicle models at preset frequency intervals, the minimum value of all sound pressure levels corresponding to each frequency interval is selected to obtain the sound pressure level at the preset frequency interval.

[0137] In an optional embodiment, the determining module 61 extracts the sound insulation at preset frequency intervals based on a second test relationship, including:

[0138] From the second test curve, extract the sound insulation of at least two vehicle models at preset frequency intervals; from the sound insulation of at least two vehicle models at preset frequency intervals, select the minimum value among all the sound insulation values ​​corresponding to each frequency interval to obtain the sound insulation value at the preset frequency interval.

[0139] In an optional embodiment, the determining module 61 uses the sound pressure level at a preset frequency interval and the sound insulation at the preset frequency interval to determine the background noise of the target order sound source at the preset frequency interval, including:

[0140] The sound pressure level and sound insulation at the preset frequency intervals are substituted into the preset order sound source background noise calculation formula to obtain the target order sound source background noise at the preset frequency intervals; wherein, the preset order sound source background noise calculation formula is determined based on the expression of the difference between the sound power level of the point sound source and the sound pressure level of the receiving point.

[0141] In an optional embodiment, the determining module 61 performs curve fitting based on preset frequency interval points and the target order sound source background noise at those preset frequency interval points to obtain the target correspondence, which includes:

[0142] The sum of the background noise of the target order sound source and the prominence of the target order pure tone at the preset frequency interval is determined as the target noise target value of the target power component at the preset frequency interval. Curve fitting is performed on the target noise target values ​​of the target power component at the frequency interval and the preset frequency interval to obtain the target correspondence.

[0143] In an optional embodiment, test module 62 is specifically used for:

[0144] When the sound pressure test value of the target power component at the preset frequency is less than or equal to the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, the target power component is determined to have passed the sound pressure test; when the sound pressure test value of the target power component at the preset frequency is greater than the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, the target power component is determined to have failed the sound pressure test.

[0145] In practical applications, the aforementioned determining module 61 and testing module 62 can be implemented by a processor located on the sound pressure testing device, specifically a central processing unit (CPU), a microprocessor (MPU), a digital signal processor (DSP), or a field programmable gate array (FPGA).

[0146] Figure 7 This is a schematic diagram of an optional sound pressure testing device provided in an embodiment of the present invention, as shown below. Figure 7 As shown, an embodiment of the present invention provides a sound pressure testing device 700, comprising:

[0147] The processor 71 and the storage medium 72 storing instructions executable by the processor 71, the storage medium 72 performing operations via the communication bus 73 in dependence on the processor 71, when the instructions are executed by the processor 71, perform the sound pressure test method described in one or more of the above embodiments.

[0148] It should be noted that in practical applications, the various components in the terminal are coupled together via the communication bus 73. It can be understood that the communication bus 73 is used to achieve communication between these components. In addition to the data bus, the communication bus 73 also includes a power bus, a control bus, and a status signal bus. However, for clarity, in... Figure 7 The general labeled all buses as communication bus 73.

[0149] This invention provides a computer storage medium storing executable instructions. When the executable instructions are executed by one or more processors, the processors execute the sound pressure testing method as described in one or more of the above embodiments.

[0150] The computer-readable storage medium can be a magnetic random access memory (FRAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, a magnetic surface memory, an optical disc, or a compact disc read-only memory (CD-ROM), etc.

[0151] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0152] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0153] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0154] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0155] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention.

Claims

1. A sound pressure level testing method, characterized in that, include: Obtain a first test relationship and a second test relationship for at least two vehicle models; wherein, the first test relationship is the test relationship between engine speed and sound pressure level; and the second test relationship is the test relationship between frequency and sound insulation. Extract the test relation under the target order from the first test relation to obtain the third test relation; Based on the third test relationship, the sound pressure level at the preset frequency interval is extracted; Based on the second test relationship, the sound insulation amount at the preset frequency interval points is extracted; The background noise of the target order sound source at the preset frequency interval is determined by using the sound pressure level at the preset frequency interval and the sound insulation at the preset frequency interval. Based on the preset frequency interval points and the target order sound source background noise at the preset frequency interval points, curve fitting is performed to obtain the target correspondence; wherein, the target correspondence is the correspondence between the critical value of frequency and sound pressure level; Based on the target correspondence, a sound pressure test is performed on the target power component to determine whether the target power component passes the sound pressure test.

2. The method according to claim 1, characterized in that, The method further includes: When the target power component is a motor, the electromagnetic force frequency order corresponding to the motor spatial module being 0 is determined as the target order.

3. The method according to claim 1, characterized in that, The method further includes: When the target power component is a speed reducer, the gear meshing order of the speed reducer is determined as the target order.

4. The method according to claim 1, characterized in that, The extraction of sound pressure levels at preset frequency intervals based on the third test relationship includes: The rotational speed in the third test relationship is frequency domain transformed to obtain the fourth test relationship; wherein, the fourth test relationship is the test relationship between frequency and sound pressure level; From the fourth test relationship, extract the sound pressure level of at least two vehicle models at preset frequency intervals; From the sound pressure levels of at least two vehicle models at preset frequency intervals, the minimum value of all sound pressure levels corresponding to each frequency interval is selected to obtain the sound pressure level at the preset frequency interval.

5. The method according to claim 1, characterized in that, The step of extracting the sound insulation at preset frequency intervals based on the second test relationship includes: Extract the sound insulation of at least two vehicle models at preset frequency intervals from the second test curve; From the sound insulation values ​​of at least two vehicle models at preset frequency intervals, select the minimum value among all the sound insulation values ​​corresponding to each frequency interval to obtain the sound insulation value at the preset frequency interval.

6. The method according to claim 1, characterized in that, The step of determining the background noise of the target order sound source at the preset frequency interval points by using the sound pressure level at the preset frequency interval points and the sound insulation at the preset frequency interval points includes: Substitute the sound pressure level at the preset frequency interval and the sound insulation at the preset frequency interval into the preset order sound source background noise calculation formula to obtain the target order sound source background noise at the preset frequency interval. The preset formula for calculating the background noise of the sound source is determined based on the expression for the difference between the sound power level of the point sound source and the sound pressure level of the receiving point.

7. The method according to claim 1, characterized in that, The step of performing curve fitting based on the preset frequency interval points and the target order sound source background noise at the preset frequency interval points to obtain the target correspondence includes: The sum of the background noise of the target order sound source at the preset frequency interval point and the prominence value of the target order pure tone is determined as the noise target value of the target power component at the preset frequency interval point. The target noise values ​​of the target power components at the frequency interval points and the preset frequency interval points are subjected to curve fitting to obtain the target correspondence.

8. The method according to any one of claims 1 to 7, characterized in that, The step of performing a sound pressure test on the target power component based on the target correspondence, and determining whether the target power component passes the sound pressure test, includes: When the sound pressure test value of the target power component at a preset frequency is less than or equal to the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, the target power component is determined to have passed the sound pressure test. When the sound pressure test value of the target power component at a preset frequency is greater than the critical value of the sound pressure level corresponding to the preset frequency in the target correspondence, it is determined that the target power component fails the sound pressure test.

9. A sound pressure testing device, characterized in that, include: The determination module is used for: Obtain a first test relationship and a second test relationship for at least two vehicle models; wherein, the first test relationship is the test relationship between engine speed and sound pressure level; and the second test relationship is the test relationship between frequency and sound insulation. Extract the test relation under the target order from the first test relation to obtain the third test relation; Based on the third test relationship, the sound pressure level at the preset frequency interval is extracted; Based on the second test relationship, the sound insulation amount at the preset frequency interval points is extracted; The background noise of the target order sound source at the preset frequency interval is determined by using the sound pressure level at the preset frequency interval and the sound insulation at the preset frequency interval. Based on the preset frequency interval points and the target order sound source background noise at the preset frequency interval points, curve fitting is performed to obtain the target correspondence; wherein, the target correspondence is the relationship between the critical value of frequency and sound pressure level; The testing module is used to perform a sound pressure test on the target power component based on the target correspondence, and to determine whether the target power component passes the sound pressure test.

10. A sound pressure testing device, characterized in that, include: The processor and a storage medium storing processor-executable instructions, the storage medium performing operations via a communication bus dependent on the processor, wherein when the instructions are executed by the processor, the sound pressure testing method according to any one of claims 1 to 8 is performed.

11. A computer storage medium, characterized in that, The device stores executable instructions, which, when executed by a processor, perform the sound pressure testing method as described in any one of claims 1 to 8.

Images