Locomotive vehicle driving system noise test method and electronic equipment

Abstract

The invention provides a locomotive vehicle driving system noise test method and electronic equipment. According to the locomotive vehicle driving system noise test method, a plurality of test points are arranged on a driving system; placing the driving system in a semi-anechoic room to carry out a no-load noise test, and outputting the sound energy level LJ of the driving system; placing the driving system in a soundproof box to carry out a no-load noise test, and outputting a sound energy level L 'J of the driving system; by obtaining a sound energy level difference value delta LJ between a driving system sound energy level LJ and a driving system sound energy level L 'J, the sound energy levels of the driving system under different working conditions of vehicle operation are calibrated so as to output the noise level of the driving system under the working conditions; and completing the test. The noise test accuracy of the driving system under the working conditions of different loads and different speeds can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of noise detection of rolling stock drive systems, and in particular to a rolling stock drive system noise test method and electronic equipment, which are suitable for technical analysis such as noise diagnosis, qualitative evaluation, analysis improvement and optimization of rail vehicle drive systems such as electric locomotives. Background Art

[0002] With the rapid development of high-speed and heavy-load rail transit, people have put forward higher requirements for vehicle comfort, especially the noise of heavy-load locomotives. The noise of heavy-load locomotives mainly includes traction fan equipment noise, traction drive system noise, and wheel-rail noise. Among them, the noise of traction fan equipment can be suppressed by adjusting the operating frequency of its variable frequency fan; wheel-rail noise can require the track to meet the track parameter requirements specified in the ISO3095 standard; the traction drive system noise is mainly composed of the current harmonic noise generated by the traction inverter and the drive system (motor + gearbox) noise.

[0003] The noise of the locomotive drive system is mainly composed of the motor current harmonic noise and the gearbox gear bonding noise. To accurately obtain the noise of the locomotive drive system, the drive system needs to exert at least 2 / 3Fmax traction load. At present, there is no matching test load system in the standard semi-anechoic chamber, which can only meet the no-load noise test of the drive system. In order to provide a load for the locomotive drive system, the test system needs to have a test motor and a test gearbox to meet the load requirements of the drive system, such as Figure 1 As shown, 1 is the tested load motor, 2 is the accompanying test load speed increase box, 3 is the accompanying test load speed reduction box, 4 is the torque meter, 5 is the tested drive system, and 6 is the non-standard soundproof box. In order to isolate the noise generated by the accompanying test system, a non-standard soundproof box is used to separate the tested drive system from the accompanying test system. At the same time, sound-absorbing cotton is laid on the inner wall of the non-standard soundproof box to eliminate reverberation in the soundproof box, so that the test results are more accurate.

[0004] However, due to the limited site, the soundproof box cannot be made into a sound-free environment with a sound absorption coefficient of more than 0.95 like the standard semi-anechoic room. Therefore, there is a low-frequency reverberation sound field in the soundproof box. In addition, the sound insulation of the soundproof box is not as good as that of the semi-anechoic room. Ultimately, the actual noise test results are larger than the real results.

[0005] Furthermore, the standard semi-anechoic chamber does not have a matching test load system, which can only meet the no-load noise test of the drive system, but cannot meet the noise requirements of the drive system under loaded conditions. In order to meet the noise test requirements of the drive system under loaded conditions, the existing test equipment is used to build a drive system Figure 1The test platform shown, at the same time, in order to eliminate the problem of large drive system noise test results caused by reverberant sound field due to space limitations of non-standard sound insulation boxes, it is necessary to provide a locomotive vehicle drive system noise test method.

[0006] In addition, for the professional names designed in this case, technicians in this field usually identify them as follows:

[0007] Semi-anechoic chamber: Its main function is to provide a semi-free field space for acoustic testing;

[0008] Soundproof box: a customized or standardized product that provides a testing environment for noise;

[0009] The different operating conditions of a vehicle include the speed of the vehicle, the load during operation, etc. Summary of the invention

[0010] The object of the present invention is to provide a method and electronic equipment for testing the noise of a locomotive vehicle drive system, which can improve the noise test accuracy of the drive system under different load and speed conditions.

[0011] The technical solution of the present invention is: a method for testing the noise of a locomotive vehicle drive system, comprising:

[0012] Step 1: Arrange multiple measuring points on the drive system;

[0013] Step 2: Place the drive system in a semi-anechoic chamber to conduct no-load noise testing and output the drive system sound energy level L J ;

[0014] Step 3: Place the drive system in a soundproof box to conduct a no-load noise test and output the drive system sound energy level L' J ;

[0015] Step 4: Get the sound energy level L of the driving system J and drive system sound energy level L' J The difference in sound energy level between J , calibrate the sound energy level of the drive system under different operating conditions of the vehicle, and complete the test with the drive system noise level under output operating conditions.

[0016] In the above scheme, the drive system no-load noise test is first carried out in a standard semi-anechoic chamber, and then the drive system is installed in a soundproof box and the drive system no-load noise test is carried out. The difference in characteristics between the two is analyzed to determine the noise impact of the sound field environment on the drive system, and finally a relatively accurate drive system noise value is obtained through correction.

[0017] The above calibration is performed by correcting the influence of the test environment and the sound absorption coefficient of the soundproof room.

[0018] Preferably, in step 2, the average sound pressure level of the drive system under different operating conditions of the vehicle is first obtained. And the average sound pressure level and test area S 1 Calculate the sound energy level L J .

[0019] Preferably, in the anechoic chamber, the sound energy level L at each measuring point is J , should be calculated according to formula (1):

[0020]

[0021] Where: It is the single event time average sound pressure level of the measured sound source in the semi-anechoic room, expressed in decibels;

[0022] S 1 is the measurement area in m 2 ; S 0 =1m 2 .

[0023] Preferably, in step 3, the average sound pressure level under the same working conditions as the drive system in the semi-anechoic chamber is obtained. According to the background noise and environmental noise at the soundproof box test site, the background noise correction coefficient K is obtained respectively. 1 and environmental noise correction factor K 2 Finally, the sound pressure level of the drive system noise in the soundproof box room is obtained Then calculate the drive system sound energy level L' measured in the soundproof box J .

[0024] Preferably, background noise correction: the average value of the time-averaged sound pressure level of the background noise in the soundproof box Use formula (2) to calculate:

[0025]

[0026] Where:

[0027] L pi(B) is the time-averaged sound pressure level of the background noise measured at the ith microphone or the ith microphone path in the soundproof box, expressed in decibels;

[0028] N M is the number of microphone positions;

[0029] Background noise correction value K 1 Formula (3) will be used to calculate:

[0030]

[0031] in:

[0032]

[0033] Where:

[0034] The time-averaged sound pressure level in the 1 / 3 octave band measured at the ith microphone position or the ith microphone path when the sound source of the driving system is running, expressed in decibels;

[0035] The time-averaged sound pressure level of the background noise in the 1 / 3 octave band measured at the ith microphone position or the ith microphone path, expressed in decibels.

[0036] Preferably, such as ΔL pi >15dB, then K 1i Zero, no background noise correction is required; if 6dB≤ΔL pi ≤15dB, should be calculated according to formula (3).

[0037] Preferably, ambient noise correction:

[0038] Correction factor K of the sound absorption driving environment of the room in the soundproof box 2

[0039]

[0040] Where:

[0041] A is the sound absorption of the room in the soundproof box, in m 2 ;

[0042] S 2 is the area of ​​the measuring surface (S 2 =S 1 ), unit is m 2 ;

[0043] The sound absorption A of the room in the soundproof box is obtained by formula (6):

[0044]

[0045] Where:

[0046] S 2 is the area of ​​the measuring surface (S 2 =S 1 ), unit is m 2 ;

[0047] S 0 =1m 2 ;

[0048] The corrected sound pressure level of the drive system noise measured in a soundproof box room

[0049]

[0050] Where:

[0051] The single event time average sound pressure level of the sound source of the driving system in the sound insulation measurement surface, expressed in decibels;

[0052] K 1 is the background noise correction factor;

[0053] K 2 is the environmental noise correction factor.

[0054] Preferably, in the soundproof room, the energy level L' at each measuring point J , should be calculated according to formula (8):

[0055]

[0056] Where:

[0057] Corrected sound pressure level for test drive system noise in a soundproof box room;

[0058] S 2 is the area of ​​the measuring surface (S 2 =S 1 ), unit is m 2 ;

[0059] S 0 =1m 2 .

[0060] Preferably, in step 4, the sound energy level L of the driving system measured in the semi-anechoic chamber is J The sound energy level L' of the drive system measured in the soundproof box J The difference in sound energy level between J Calculate according to formula (9)

[0061] ΔL J =L' J -L J (9).

[0063] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned locomotive vehicle drive system noise test method when executing the computer program.

[0064] Compared with the related art, the present invention has the following beneficial effects:

[0065] First, the present invention first carries out a no-load noise test of the drive system in a standard semi-anechoic chamber, and then installs the drive system in a soundproof box to carry out a no-load noise test of the drive system. The noise impact value of the sound field environment on the drive system is obtained through the difference analysis of the characteristics of the two, and finally a relatively accurate noise value of the drive system is obtained through correction;

[0066] Second, because the drive system noise test must at least exert 2 / 3Fmax load, the load system will generate relatively large noise during the test; at the same time, the clearance size in the soundproof box is limited and there will be reverberation, which will cause the drive system noise test value to be larger than the actual value. Through the method of the present invention, the noise results of the drive system tested in the soundproof box can be calibrated, which can improve the noise test accuracy of the drive system under different load and speed conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 Schematic diagram of the noise test device for the locomotive vehicle drive system. DETAILED DESCRIPTION

[0068] The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict. For the convenience of description, if the words "upper", "lower", "left" and "right" appear in the following, they only indicate that the upper, lower, left and right directions are consistent with the drawings themselves, and do not limit the structure.

[0069] A vehicle driving system noise test method provided in this embodiment includes:

[0070] Step 1: Arrange 9 microphones 500mm from the surface of the drive system, distributed on the 5 surfaces of the transmission device. Based on the center height of the drive system, arrange 1 measuring point at the center of each corresponding surface 500mm away from the front, back, left, right and top surfaces of the drive system. Arrange 4 measuring points at the intersection between the front, back, left and right surfaces of the drive system, with the height consistent with the height of the measuring point at the center of the top surface. Form a rectangular enveloping surface, divided into upper and lower layers with a total of 9 measuring points.

[0071] Step 2: Place the drive system (gearbox and traction motor) in a semi-anechoic chamber. The sound insulation of the semi-anechoic chamber is 60 dB, the cut-off frequency is 50 Hz, the sound absorption coefficient is above 0.97, and the clearance size (length × width) is 9 m × 8 m × 5.5 m. Obtain the noise data of the drive system at different speeds under no-load conditions.

[0072] Test drive system sound energy level in semi-anechoic chamber:

[0073] In a semi-anechoic room, the acoustic functional energy or A-weighted sound energy level L of each measurement frequency band under reference meteorological conditionsJ , should be calculated according to formula (1):

[0074]

[0075] Where:

[0076] It is the single event time average sound pressure level of the measured sound source on the measurement surface in the semi-anechoic room, expressed in decibel (dB);

[0077] S 1 The unit of measurement is square meter (m 2 ).

[0078] As S 0 =1m 2 .

[0079] Step 3: Place the drive system (gearbox and traction motor) in a soundproof room to isolate the interference noise from external equipment. Figure 1 As shown. The sound insulation of the soundproof room is ≥30dB. The cut-off frequency is 200Hz, and the sound absorption coefficient is above 0.85. The clearance size is 4m×4m×3m. The measurement points in the silent box are arranged exactly the same as those in the semi-anechoic room.

[0080] Sound energy level of the drive system tested in a non-standard soundproof box:

[0081] Because the walls and ceiling of the soundproof box are paved with attracting materials, but the cut-off frequency is 200Hz, there is a certain reverberation in the box. Therefore, the noise test results in the box need to be further corrected.

[0082] Step 3.1, background noise correction

[0083] Mean value of the time-averaged sound pressure level of background noise in the soundproof box Use formula (2) to calculate:

[0084]

[0085] Where:

[0086] L pi(B) is the time-averaged sound pressure level of the background noise measured at the ith microphone or the ith microphone path in the soundproof box, expressed in decibels (dB);

[0087] N M is the number of microphone positions.

[0088] Background noise correction value K 1 Formula (3) will be used to calculate:

[0089]

[0090] in:

[0091]

[0092] Where:

[0093] The time-averaged sound pressure level in the 1 / 3 octave band measured at the ith microphone position or the ith microphone path when the sound source of the driving system is in operation, expressed in decibels (dB);

[0094] The time-averaged sound pressure level in the 1 / 3 octave band of the background noise measured at the ith microphone position or the ith microphone path, expressed in decibels (dB).

[0095] If ΔL pi >15dB, then K 1i Zero, no background noise correction is required.

[0096] If 6dB≤ΔL pi ≤15dB, should be calculated according to formula (3).

[0097] If one or more 1 / 3 octave bands have a ΔL pi <6dB, the accuracy of the measurement results will decrease, K 1i The value of ΔL is 1.3dB in these frequency bands. pi =6dB). In this case, it is necessary to clearly state in the report and in the graphs and tables of results that the data in these frequency bands represent the upper limit of the sound power level of the sound source being measured.

[0098] Step 3.2, Environmental Noise Correction

[0099] First, according to the room sound absorption driving environment correction factor K 2

[0100]

[0101] Where:

[0102] A is the sound absorption of the room in the soundproof box, in square meters (m 2 );

[0103] S 2 is the area of ​​the measuring surface S 2 =S 1 , the unit is square meters (m 2 ).

[0104] The sound absorption A of the room in the soundproof box is obtained by formula (6):

[0105]

[0106] In the formula

[0107] S 2 is the area of ​​the measuring surface (S 2 =S 1 ), unit is square meter (m 2 );

[0108] S 0 =1m 2 ;

[0109] Therefore, the corrected sound pressure level of the drive system noise is measured in the soundproof box room.

[0110]

[0111] Where:

[0112] It is the time-averaged sound pressure level of a single event of the sound source of the driving system in the measurement surface of the sound insulation, expressed in decibels (dB);

[0113] K 1 is the background noise correction factor;

[0114] K 2 is the environmental noise correction factor.

[0115] The acoustic energy or A-weighted sound energy level L' of the driving system noise in each measurement frequency band in the soundproof box room J , should be calculated according to formula (8):

[0116]

[0117] Where:

[0118] Corrected sound pressure level for test drive system noise in a soundproof box room;

[0119] S 2 is the area of ​​the measuring surface (S 2 =S 1 ), unit is square meter (m 2 );

[0120] S 0 =1m 2 .

[0121] Step 4: The final sound energy level L of the drive system measured in the semi-anechoic chamber is J The sound energy level L' of the drive system measured in the soundproof box J The difference in sound energy level between J

[0122] ΔL J =L' J -L J (9)

[0123] The difference in sound energy level ΔL between different test environments can be used J , calibrate the sound energy level of the drive system under the same load and different speeds, so as to qualitatively analyze the noise level of the drive system under different load conditions.

[0124] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned locomotive vehicle drive system noise test method when executing the computer program.

[0125] The present invention mainly uses the sound energy level obtained in the semi-anechoic chamber to calibrate the sound energy level of the drive system noise in the soundproof box. The sound energy level of the drive system can also be obtained in the reverberation chamber to calibrate the sound energy level of the drive system tested in the soundproof box, and the sound energy level of the drive system after the soundproof box is used to separate the load system and the power system noise, which are all within the technical scope of the present invention.

[0126] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for testing the noise of a locomotive vehicle drive system, characterized in that: include: Step 1: Arrange multiple measuring points on the drive system; Step 2: Place the drive system in a semi-anechoic chamber to conduct no-load noise testing and output the drive system sound energy level L J ; Step 3: Place the drive system in a soundproof box to conduct a no-load noise test and output the drive system sound energy level L' J ; Step 4: Get the sound energy level L of the driving system J and drive system sound energy level L' J The difference in sound energy level between J , calibrate the sound energy level of the drive system under different operating conditions of the vehicle, so as to output the noise level of the drive system under the operating conditions; Complete the experiment.

2. The method for testing the noise of a locomotive vehicle driving system according to claim 1, characterized in that: In step 2, the average sound pressure level of the drive system under different operating conditions of the vehicle is first obtained. And the average sound pressure level Calculate the sound energy level L using the test area S1 J .

3. The method for testing the noise of a locomotive vehicle driving system according to claim 2, characterized in that: In the anechoic chamber, the sound energy level L at each measuring point J , should be calculated according to formula (1): Where: It is the single event time average sound pressure level of the measured sound source in the semi-anechoic room, expressed in decibels; S1 is the area of ​​the measuring surface, in m 2 ; S0=1m 2 。 4. The method for testing the noise of a locomotive vehicle driving system according to claim 1, characterized in that: In step 3, obtain the average sound pressure level under the same working conditions as the drive system in the semi-anechoic chamber According to the background noise and environmental noise at the soundproof box test site, corrections are made to obtain the background noise correction coefficient K1 and the environmental noise correction coefficient K2 respectively, and finally the sound pressure level of the drive system noise in the soundproof box room is obtained after correction. Then calculate the drive system sound energy level L' measured in the soundproof box J .

5. The method for testing the noise of a locomotive vehicle driving system according to claim 4, characterized in that: Background noise correction: the average value of the time-averaged sound pressure level of the background noise in the soundproof box Use formula (2) to calculate: Where: L pi(B) is the time-averaged sound pressure level of the background noise measured at the ith microphone or the ith microphone path in the soundproof box, expressed in decibels; N M is the number of microphone positions; The background noise correction value K1 will be calculated using formula (3): in: Where: The time-averaged sound pressure level in the 1 / 3 octave band measured at the ith microphone position or the ith microphone path when the sound source of the driving system is running, expressed in decibels; The time-averaged sound pressure level of the background noise in the 1 / 3 octave band measured at the ith microphone position or the ith microphone path, expressed in decibels.

6. The method for testing the noise of a locomotive vehicle driving system according to claim 5, characterized in that: As ΔL pi >15dB, then K 1i Zero, no background noise correction is required; if 6dB≤ΔL pi ≤15dB, should be calculated according to formula (3).

7. The method for testing the noise of a locomotive vehicle driving system according to claim 4, characterized in that: Ambient Noise Correction: Sound absorption driving environment correction factor K2 of the room in the soundproof box Where: A is the sound absorption of the room in the soundproof box, in m 2 ; S2 is the area of ​​the measuring surface, in m 2 ; The sound absorption A of the room in the soundproof box is obtained by formula (6): Where: S2=S1,unit is m 2 ; S0=1m 2 ; The corrected sound pressure level of the drive system noise measured in a soundproof box room Where: The single event time average sound pressure level of the sound source of the driving system in the sound insulation measurement surface, expressed in decibels; K1 is the background noise correction coefficient; K2 is the environmental noise correction factor.

8. The method for testing the noise of a locomotive vehicle driving system according to claim 4, characterized in that: In the soundproof room, the energy level L' at each measuring point J , should be calculated according to formula (8): Where: Corrected sound pressure level for test drive system noise in a soundproof box room; S2 is the area of ​​the measuring surface, in m 2 ; S0=1m 2 。 9. The method for testing the noise of a locomotive vehicle driving system according to claim 1, characterized in that: In step 4, the sound energy level L of the drive system measured in the semi-anechoic chamber is J The sound energy level L' of the drive system measured in the soundproof box J The difference in sound energy level between J Calculate according to formula (9) ΔL J =L' J -L J (9)。 10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the locomotive vehicle drive system noise test method as described in any one of claims 1-9 is implemented.

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