WO2019019801A1 - 新能源车及其主动降噪方法和系统 - Google Patents

新能源车及其主动降噪方法和系统 Download PDF

Info

Publication number
WO2019019801A1
WO2019019801A1 PCT/CN2018/089323 CN2018089323W WO2019019801A1 WO 2019019801 A1 WO2019019801 A1 WO 2019019801A1 CN 2018089323 W CN2018089323 W CN 2018089323W WO 2019019801 A1 WO2019019801 A1 WO 2019019801A1
Authority
WO
WIPO (PCT)
Prior art keywords
noise
signal
frequency
motor
sound
Prior art date
Application number
PCT/CN2018/089323
Other languages
English (en)
French (fr)
Inventor
赵永吉
孙亚轩
刘文展
郝一妃
严竹芳
Original Assignee
比亚迪股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 比亚迪股份有限公司 filed Critical 比亚迪股份有限公司
Publication of WO2019019801A1 publication Critical patent/WO2019019801A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/128—Vehicles
    • G10K2210/1282—Automobiles
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3025—Determination of spectrum characteristics, e.g. FFT

Definitions

  • the present disclosure relates to the field of noise control technologies, and in particular, to an active noise reduction method for a new energy vehicle, an active noise reduction system for a new energy vehicle, and a new energy vehicle.
  • the high frequency noise of the motor is a result of noise synthesis, including mechanical noise, electromagnetic noise and air noise.
  • the frequency is from 1KHz to 12KHz or higher. This high frequency electromagnetic noise will bring people Strong discomfort. Therefore, the management of such noise is very necessary.
  • noise reduction schemes There are two main types of noise reduction schemes, one is passive noise reduction, also called physical noise reduction. Including structural optimization, eliminating resonance, damping materials for sound absorption and so on.
  • the other is active noise reduction, including active noise reduction and masking effects, as well as other sound compensation measures.
  • the sound compensation is to add other sound components on the basis of the original noise to change the characteristics of the original sound (constructing noise, forming "harmonic noise").
  • the theoretical support of this method comes from music acoustics, in music. In acoustics, the fundamental frequency determines the pitch, and the overtone determines the tone. The noise of the motor in the new energy car sounds so harsh because of the lack of overtones. So the sound component we need to construct can be understood as the overtone of the motor noise.
  • the method of sound compensation is simple to implement and is very effective in improving sound quality.
  • the effective method for active noise reduction by constructing noise is as follows: find the overtone component of the motor noise signal, perform subjective evaluation, select the overtone components with high subjective evaluation, store the spare, and correlate the noise signal of the motor. Associated with the motor speed, when the motor speed is a certain value, the relevant overtone component is called, and the overtone component is played by the car audio device, so that the overtone component played by the car audio device can be integrated with the motor noise. For noise reduction processing. To a certain extent, this can greatly improve the sound quality of the motor noise signal and improve the driving experience.
  • the inventor of the present disclosure found in the development process that the above-mentioned active noise reduction method still has certain defects, and along with the increase of the vehicle speed, the proportion of other non-motor noises starts to increase (road noise, tire noise, destructive vibration noise, etc.) In this way, while the motor noise signal is compensated, it will interfere with other non-motor noises to form new characteristic signals.
  • These characteristic signals may be enhanced noise signals, which have a negative effect on improving the acoustic environment quality.
  • the present disclosure provides a new energy vehicle and an active noise reduction method and system thereof.
  • An aspect of the present disclosure provides an active noise reduction method for a new energy vehicle, including the following steps:
  • Controlling converting the noise reduction structure signal into a noise reduction frequency signal, and adjusting a sound pressure level of the noise reduction frequency signal according to a sound pressure level of the motor noise;
  • the noise reduction frequency signal is input into the sound playing device for playing to output a noise reduction structure sound to perform noise reduction processing on the motor noise of the new energy vehicle.
  • the active noise reduction method of the new energy vehicle disclosed in the present disclosure collects the frequency of the non-motor noise and the sound pressure level of the motor noise in the acoustic environment in real time, and acquires the operating parameters of the new energy vehicle and the frequency of the non-motor noise and the motor noise.
  • a sound pressure level a sound pressure level
  • the noise reduction structure sound played by the sound playing device is combined with the acoustic environment noise, and the noise reduction structure signal is generated not only considering the frequency of the motor noise signal, but also comprehensively considering the sound of other non-motor noise and motor noise in the acoustic environment.
  • the magnitude of the pressure level avoids the problem that the structure signal generated by the frequency of a single motor noise signal is easily combined with other non-motor noise components to form a new enhanced noise signal due to overlap, interference, etc., resulting in a deterioration of the acoustic environment quality, thereby making it better.
  • Improve the quality of the acoustic environment The open and improved active noise reduction method can effectively solve the noise problem brought by the vehicle speed increase, and the method is easy to implement and simple and easy to operate.
  • the “acquiring the operating parameters of the new energy vehicle” is specifically obtained by reading data information transmitted by the CAN bus of the new energy vehicle to implement acquisition of the operating parameter.
  • the generating a noise reduction configuration signal according to the collected frequency of the non-motor noise in the acoustic ambient noise and the acquired frequency of the motor noise signal specifically includes the following steps:
  • the constructed sound signal is adjusted according to the collected frequency of the non-motor noise in the acoustic ambient noise to generate the noise reduction configuration signal.
  • the “acquiring a structured sound signal corresponding to the motor noise signal by calling a preset configuration sound database according to the frequency of the motor noise signal” specifically includes the following steps:
  • the preset structured sound database stores A plurality of constructed sound samples, each constructed sound sample corresponding to a noise band, and including a constructed sound signal corresponding to the noise band.
  • the preset structured sound database is obtained by the following steps:
  • Each synthesized sound sample is scored according to a preset evaluation method, and a structured sound signal corresponding to the calibration noise signal of the selected frequency band is acquired from the preselected constructed sound signal according to the score result of each synthesized sound sample.
  • the “modulating the sound signal according to the frequency of the non-motor noise in the acoustic environment noise collected to generate the noise reduction structure signal” specifically includes the following steps:
  • the frequency of the constructed sound signal is removed from the frequency of the repeated non-motor noise in the acoustic ambient noise to generate the noise reduction configuration signal.
  • the “constructing a sound signal corresponding to the motor noise signal by the generation function according to the frequency of the motor noise signal” specifically includes the following steps:
  • the motor noise signal includes a fundamental wave and a harmonic, a fundamental frequency is obtained from a frequency of the motor noise signal, and the constructed sound signal is obtained by a generation function according to a musical acoustic or psychoacoustic principle, the constructed sound signal a subharmonic of a fundamental wave in the motor noise signal; wherein the frequency of the constructed sound signal is the fundamental frequency
  • n and m are natural numbers and n is less than m.
  • the second aspect of the present disclosure provides an active noise reduction system for a new energy vehicle, including:
  • Acoustic ambient noise collecting device for collecting acoustic ambient noise in an acoustic environment of a new energy vehicle, the acoustic ambient noise including motor noise and non-motor noise;
  • a noise reduction controller configured to acquire a frequency of the non-motor noise and a sound pressure level of the motor noise; and acquire an operating parameter of the new energy vehicle, and acquire an operation parameter according to the operating parameter a frequency of the motor noise signal; wherein the operating parameter includes at least a motor speed of the new energy vehicle; and based on the collected frequency of the non-motor noise in the acoustic ambient noise and the obtained motor noise signal a frequency, generating a noise reduction configuration signal; then controlling the noise reduction configuration signal to be converted into a noise reduction frequency signal, and adjusting a sound pressure level of the noise reduction frequency signal according to a sound pressure level of the motor noise;
  • the sound playback device is disposed in the new energy vehicle for outputting the noise reduction structure sound to perform noise reduction processing on the motor noise of the new energy vehicle.
  • the active noise reduction system of the new energy vehicle collects the frequency of non-motor noise and the sound pressure level of the motor noise in the acoustic environment in real time through the environmental noise collecting device. Obtaining the operating parameters of the new energy vehicle and the frequency of the non-motor noise and the sound pressure level of the motor noise through the noise reduction controller; thereby obtaining the frequency of the motor noise signal corresponding to the operating parameter, and simultaneously, according to the collected acoustic environment a frequency of the non-motor noise in the noise and the obtained frequency of the motor noise signal, generating a noise reduction configuration signal; converting the noise reduction configuration signal into a noise reduction frequency signal, and according to the sound pressure level of the motor noise And adjusting a sound pressure level of the noise reduction frequency signal; then inputting the noise reduction frequency signal into a sound playing device for playing to output a noise reduction structure sound.
  • the noise reduction structure sound played by the sound playing device is combined with the acoustic environment noise, and the noise reduction structure signal is generated not only considering the frequency of the motor noise signal, but also comprehensively considering the sound of other non-motor noise and motor noise in the acoustic environment.
  • the magnitude of the pressure level avoids the problem that the structure signal generated by the frequency of a single motor noise signal is easily combined with other non-motor noise components to form a new enhanced noise signal due to overlap, interference, etc., resulting in a deterioration of the acoustic environment quality, thereby making it better.
  • Improve the quality of the acoustic environment can effectively solve the noise problem brought about by the increase of the vehicle speed, is convenient for the user to use, has low cost, and does not add an additional cost burden to the product.
  • noise reduction controller specifically includes:
  • a data acquisition module configured to acquire a frequency of the non-motor noise and a sound pressure level of the motor noise; acquire an operating parameter of the new energy vehicle, and acquire, according to the operating parameter, an operation parameter associated with the operating parameter a frequency of the motor noise signal; wherein the operating parameter includes at least a motor speed of the new energy vehicle;
  • a signal generating module configured to generate a noise reduction structure signal according to the collected frequency of the non-motor noise in the acoustic environment noise and the acquired frequency of the motor noise signal;
  • the signal conversion module is configured to input the noise reduction frequency signal into a sound playing device to output a noise reduction structure sound to perform noise reduction processing on the motor noise of the new energy vehicle.
  • the signal conversion module is a digital to analog conversion module.
  • the acoustic environment noise collecting device is disposed in a new energy vehicle.
  • the sound playback device is a car audio system in a new energy vehicle.
  • a third aspect of the present disclosure provides a new energy vehicle including the active noise reduction system described above.
  • the new energy vehicle provided by the present disclosure has an active noise reduction system, and collects the frequency of non-motor noise and the sound pressure level of the motor noise in the acoustic environment in real time through the environmental noise collecting device. Obtaining the operating parameters of the new energy vehicle and the frequency of the non-motor noise and the sound pressure level of the motor noise through the noise reduction controller; thereby obtaining the frequency of the motor noise signal corresponding to the operating parameter, and simultaneously, according to the collected acoustic environment a frequency of the non-motor noise in the noise and the obtained frequency of the motor noise signal, generating a noise reduction configuration signal; converting the noise reduction configuration signal into a noise reduction frequency signal, and according to the sound pressure level of the motor noise And adjusting a sound pressure level of the noise reduction frequency signal; then inputting the noise reduction frequency signal into a sound playing device for playing to output a noise reduction structure sound.
  • the noise reduction structure sound played by the sound playing device is combined with the acoustic environment noise, and the noise reduction structure signal is generated not only considering the frequency of the motor noise signal, but also comprehensively considering the sound of other non-motor noise and motor noise in the acoustic environment.
  • the magnitude of the pressure level avoids the problem that the structure signal generated by the frequency of a single motor noise signal is easily combined with other non-motor noise components to form a new enhanced noise signal due to overlap, interference, etc., resulting in a deterioration of the acoustic environment quality, thereby making it better.
  • Improve the quality of the acoustic environment can effectively solve the noise problem brought about by the increase of the vehicle speed, is convenient for the user to use, has low cost, and does not add an additional cost burden to the product.
  • FIG. 1 is a flow chart of an active noise reduction method for a new energy vehicle provided in a specific embodiment of the present disclosure
  • FIG. 2 is a flow chart of step S3 in Figure 1;
  • FIG. 3 is a flow chart of a specific embodiment of step S31 of Figure 2;
  • Figure 4 is a flow chart of a specific embodiment of step S312 of Figure 3;
  • Figure 5 is a schematic diagram of a constant frequency howling spectrum
  • Figure 6 is a schematic diagram of a frequency conversion whistle spectrum
  • FIG. 7 is a block diagram of an active noise reduction system of a new energy vehicle provided in a specific embodiment of the present disclosure.
  • FIG. 8 is a detailed block diagram of an active noise reduction system of a new energy vehicle provided in a specific embodiment of the present disclosure
  • FIG. 9 is a block diagram of a new energy vehicle provided in an embodiment of the present disclosure.
  • acoustic environment noise acquisition device 1, acoustic environment noise acquisition device; 2, noise reduction controller; 3, sound playback device; 21, data acquisition module; 22, signal generation module; 23, signal conversion module; 100, active noise reduction system; New energy vehicles.
  • the generation of structured sound playback in the present disclosure to denoise high frequency motor noise is primarily the use of psychoacoustic and musical acoustics.
  • psychoacoustics the human ear is relatively unacceptable for high-frequency signals, especially the narrow-band high-frequency signals, which can greatly arouse people's irritability and even cause physical discomfort (motion sickness, nausea). But when this high-frequency noise signal and other frequency components form a new sound signal, people are very happy to accept it.
  • An interesting example is that we like the singer's treble very much, but it is difficult to accept metal objects. The "beep" sound of the glass, although the center frequency of the two may be similar.
  • the sound we hear is composed of two parts, the fundamental wave and harmonics (overtone).
  • the frequency of the harmonics is the frequency of the fundamental wave.
  • the fundamental frequency determines the pitch
  • the harmonic frequency determines the tone
  • the pitch determines that the sound "sounds”
  • the tone determines the sound "beauty is not beautiful.” This can explain the singer's high-pitched sound and the "beep" sound of metal objects across the glass.
  • the center frequency is similar, the subjective feelings are different, and the overtones are different.
  • the frequency of motor noise is generally high. If the harmonic components are constructed according to the principle of musical acoustics, the subjective feeling may be improved, but due to the increase of high frequency components, the irritability is also increased. Will increase, can not achieve the purpose of improving the environmental sound quality. So we think backwards, adding the fractional harmonics (referred to as subharmonic components) of the high-frequency signal, the structural mechanism is still the relevant principle of musical acoustics.
  • the effect of adding fractional harmonics and adding harmonics in the subjective feeling is the same, both can improve the sound quality, and their interpretation in the physical mechanism is the same, that is, the probability of the coincidence of the two signals is the same, for example, the base
  • the frequency is 5000Hz
  • the harmonic frequency is 10000Hz
  • the harmonics coincide with the fundamental frequency once every two vibrations.
  • the frequency ratio of the harmonic frequency to the fundamental frequency is 2:1; the fundamental frequency is 5000Hz, and the subharmonic component is At 2500 Hz, the fundamental frequency coincides with the subharmonic harmonics twice per vibration, and the frequency ratio of the fundamental frequency to the harmonic frequency is 2:1; the two are the same.
  • the so-called sound pressure level is an indicator of the magnitude of the sound pressure.
  • the sound pressure is the change caused by the atmospheric pressure after the sound wave is disturbed, that is, the residual pressure of the atmospheric pressure, which is equivalent to the superposition of a sound wave disturbance on the atmospheric pressure.
  • the pressure changes.
  • the unit is Pascal (Pa).
  • the sound pressure level is expressed by 20 times the common logarithm of the ratio of the sound pressure P of a sound to the basic sound pressure value P0, that is, 20 lg P/P0 in decibels (dB).
  • This embodiment provides an active noise reduction method for a new energy vehicle, including the following steps:
  • Step S1 Acoustic ambient noise collecting step: collecting acoustic ambient noise in a sound environment of a new energy vehicle, the acoustic ambient noise including motor noise and non-motor noise;
  • the so-called acoustic environment refers to a system composed of all sounds in a certain area.
  • the acoustic environment of the so-called new energy vehicle refers to the internal environment of the new energy vehicle.
  • the space where the driver and the passenger are located for example In the cab (or in the co-pilot, the effect is equivalent).
  • the so-called acoustic ambient noise refers to the noise experienced by the driver or the passenger in the acoustic environment, and is specifically collected by the acoustic environment noise collecting device described in Embodiment 2.
  • the acoustic ambient noise includes high frequency noise originating from the motor, which is called motor noise.
  • motor noise high frequency noise originating from the motor
  • the frequency of the howling sound can be generally divided into two categories, one is frequency. Unchanged, we call it constant frequency howling, and the other type is frequency conversion. We call it frequency conversion howling.
  • Both of the above whistle are high frequency motor noise.
  • it also includes other non-motor noises such as road noise, tire noise, deconstructed vibration noise, etc. These non-motor noise frequencies are relatively low.
  • the noise also belongs to the sound
  • the parameters that characterize the noise of the acoustic environment also include the frequency, the sound pressure level and the like.
  • the sound pressure level of the motor noise and other non-motor noise frequencies are collected for subsequent generation of the noise reduction structure signal and the sound pressure level of the noise reduction structure signal, so that the sound pressure level is played in the sound playback device.
  • Reasonable noise reduction structure that can be combined with motor noise to achieve active noise reduction.
  • Step S2 a data acquisition step: acquiring a frequency of the non-motor noise and a sound pressure level of the motor noise; acquiring an operation parameter of the new energy vehicle, and acquiring, according to the operation parameter, the operation parameter The frequency of the motor noise signal; wherein the operating parameter includes at least the motor speed of the new energy vehicle.
  • the acquisition of operational parameters may be accomplished by reading data information transmitted by the CAN bus of the new energy vehicle.
  • the operating parameters of the new energy vehicle may also include the speed of the new energy vehicle, the throttle opening, and the like.
  • the relationship between the motor rotational speed and the frequency of its motor noise signal can be stored in advance.
  • the CAN bus of the new energy vehicle can be connected, and the operating parameters such as the motor speed, the vehicle speed and the throttle opening can be obtained by reading the data transmitted by the CAN bus of the new energy vehicle.
  • the relationship between the pre-stored motor speed and the frequency of the motor noise signal can be obtained through the CAN bus, and the frequency of the corresponding motor noise signal can be obtained from the motor speed.
  • the operating parameter is taken as an example of the motor speed.
  • the motor speed of the new energy vehicle and the motor noise signal corresponding to the motor speed can be collected; then the frequency domain analysis of the collected motor noise signal can be performed by the spectrum analyzer to obtain the spectral characteristics of the motor noise signal.
  • the parameters of the acoustic environment noise collected in step S1 can be transmitted through the CAN bus. Similarly, the data transmitted by the CAN bus of the new energy vehicle can also be read to achieve the frequency of the non-motor noise and the motor noise. The collection of sound pressure levels.
  • Step S3 The noise reduction configuration signal generating step: generating a noise reduction structure signal according to the collected frequency of the non-motor noise in the acoustic environment noise and the acquired frequency of the motor noise signal.
  • the noise reduction structure signal generating step is more advantageous than the existing method of generating only the noise of a single motor noise signal, which can be further regulated by the frequency of the non-motor noise in the acoustic environment noise, so that The noise reduction structure signal generated by it is more reasonable. It avoids the problem that the structure signal generated by the frequency of a single motor noise signal is easily combined with other non-motor noise components to form a new enhanced noise signal due to overlap, interference, etc., resulting in a decrease in the quality of the acoustic environment, thereby improving the quality of the acoustic environment. .
  • step S3 is specifically implemented by the following steps:
  • Step S31 constructing a sound signal acquiring step: acquiring a structured sound signal corresponding to the motor noise signal by calling a preset constructed sound database according to a frequency of the motor noise signal; or, according to a frequency of the motor noise signal A constructed sound signal corresponding to the motor noise signal is obtained by a generation function.
  • step S31 it can be obtained by the above two methods. The following is explained one by one.
  • the first configuration sound signal acquisition manner is obtained by calling a preset configuration sound database according to the frequency of the motor noise signal to acquire a constructed sound signal corresponding to the motor noise signal, specifically obtained by the step of FIG.
  • Step S311 determining, according to the frequency of the motor noise signal, a frequency band to which the motor noise signal belongs;
  • Step S312 calling the preset structured sound database according to the frequency band of the motor noise signal to acquire a constructed sound signal corresponding to the frequency band of the motor noise signal; wherein the preset structured sound database A plurality of constructed sound samples are stored, each constructed sound sample corresponding to a noise frequency band, and includes a structured sound signal corresponding to the noise frequency band.
  • a preset structure sound database can be called through the CAN bus, and the data can be obtained from The high frequency signal corresponds to a constructed sound signal, such as a low frequency structured sound signal of 600-1000 Hz.
  • step S312 The structure sound database in step S312 needs to be obtained in advance through the steps shown in FIG. 4:
  • Step S3121 Acquire operating parameters of the new energy vehicle under different working conditions, and simultaneously collect motor noise signals of the new energy vehicle; where the motor noise signal of the new energy vehicle is different from the motor noise collected in the acoustic environment collecting device.
  • the noise collected by the acoustic environment acquisition device includes not only motor noise but also non-motor noise. Therefore, the requirement for motor noise is relatively low, although the relationship between the motor speed and the motor noise can also be established, but The accuracy is not high. Therefore, among the various parameters collected in the acoustic environment acquisition device, we use the sound pressure level of the motor noise and other non-motor noise frequencies. The frequency of the motor noise is not used for the generation of the noise reduction construction signal.
  • the acquisition of high-frequency noise of the motor must be precise. If the noise is collected by the noise device, other non-motor high-frequency noises, such as the friction noise of the car body, the horn sound, the noise outside the car, etc., will be collected.
  • the noise reduction construction signal has an effect.
  • the frequency of the motor noise signal and the motor speed are correspondingly established, and the motor noise signal can be directly collected in the vicinity of the motor (in the motor compartment where the motor is arranged), thereby ensuring the integrity of the collected motor noise signal and eliminating Uncertainties such as attenuation caused by noise during propagation. And to prevent other non-motor noise from interfering.
  • the noise generated by the motor can be collected in real time by one or a combination of the rotational speed sensors in the sound signal receiver (such as a microphone or the like).
  • the speed sensor can be used to collect noise.
  • noise can be collected simultaneously by the speed sensor and the sound signal receiver to improve the noise collection accuracy.
  • Step S3122 Perform spectrum analysis on the motor noise signal to obtain noise spectrum feature information associated with the operating parameter, and establish a relationship between the operating parameter and the frequency of the motor noise signal according to the noise spectrum feature information. Correspondence relationship;
  • the operating parameter is taken as an example of the motor speed.
  • the motor speed of the new energy vehicle and the motor noise signal corresponding to the motor speed can be collected; then the frequency domain analysis of the collected motor noise signal can be performed by the spectrum analyzer to obtain the spectral characteristics of the motor noise signal.
  • Step S3123 Perform frequency band division on the motor noise signal under different operating conditions according to the noise spectrum characteristic information to obtain a calibration noise signal of multiple frequency bands;
  • the frequency of the motor noise signal can be divided into high frequency, low frequency, constant frequency, frequency conversion, etc. according to the motor rotation speed. It can be understood that when the motor speed is large, it can be corresponding to high frequency noise; when the motor speed is small, it can be corresponding to low frequency noise; when the motor speed changes little, that is, when it is basically constant, it can be corresponding to constant frequency noise; the motor speed is gradually increased. That is, when there is acceleration and the acceleration is greater than a certain value, it may be corresponding to the variable frequency noise.
  • the frequency division of the motor noise signal is to save the workload when performing frequency construction.
  • high-frequency components in the ambient noise of the vehicle may have a strong sharpness, and a low-frequency component may be appropriately added in the frequency structure to increase a large number of intermediate frequency components.
  • the frequency of the motor noise signal is a high frequency, such as 3000-6000 Hz, and a sound of 600-1000 Hz can be constructed to be added to the high frequency noise.
  • Step S3124 selecting a calibration noise signal of any frequency band, and performing frequency configuration on the calibration noise signal of the selected frequency band according to a musical acoustic or psychoacoustic principle to generate a plurality of preselected construction sound signals;
  • the noise signal of the frequency band can be frequency-structured using sound processing software (such as MATLAB) according to musical acoustic or psychoacoustic principles to generate a plurality of constructed sound signals.
  • sound processing software such as MATLAB
  • Step S3125 synthesizing the calibration noise signals of the selected frequency bands with each of the preselected construction sound signals to generate a plurality of synthesized sound samples and outputting, wherein the frequency band of each synthesized sound sample includes the selected frequency band.
  • the frequency band of each synthesized sound sample belongs to the selected frequency band.
  • the frequency structure is used to obtain the low-frequency signal in the 400-500 Hz band, and the frequency of the synthesized sound sample obtained by the combination of the two can be 400-6000 Hz, visible, 400-6000 Hz band. Includes the 4000-5000Hz band.
  • the frequency of the noise signal of the selected frequency band can be compensated, that is, the frequency coverage of the synthesized sound sample is wide.
  • Step S3126 scoring each synthesized sound sample according to a preset evaluation method, and acquiring a structured sound corresponding to the calibration noise signal of the selected frequency band from the preselected constructed sound signal according to the score result of each synthesized sound sample. signal.
  • the preset evaluation method may include: 1) determining an evaluator, the evaluator should have normal hearing, and may be a general staff member, the number of people may be required to be more than 10; 2) the scoring standard may be scored by a percentage system, and Use five-level evaluation criteria, such as: excellent: very pleasant (eg, sounds comfortable, calm, pleasant) (80-100 points), good: sweet (60-80 points), medium: generally 40-60 points) Poor: ugly (20-40 points), inferior: difficult to listen to (eg, unpleasant, disturbing, irritating, etc.) (0-20 points), that is, the evaluator can perform a percentage system based on the rating evaluation; 3) Audition conditions, such as audition evaluation in a quieter indoor environment.
  • an evaluation evaluator consisting of 10 male and female adults plays each synthesized sound sample corresponding to the selected frequency band in a relatively quiet indoor environment, and each synthesized sound sample can be played 3 times. After playing 3 times, the scores are scored by 20 evaluators. After the score is completed, the score results are mathematically counted to select the synthesized sound samples with the highest score (eg, the highest average score), and the synthetic sound samples are preselected.
  • the sound sample is constructed as a constructed sound sample corresponding to the noise signal of the selected frequency band.
  • the constructed sound samples corresponding to the noise signals of each frequency band can be obtained, and the set of all constructed sound samples is the preset constructed sound database.
  • the second construction sound acquisition method is described as follows:
  • the motor noise signal includes a fundamental wave and a harmonic, a fundamental frequency is obtained from a frequency of the motor noise signal, and the constructed sound signal is obtained by a generation function according to a musical acoustic or psychoacoustic principle, the constructed sound signal a subharmonic of a fundamental wave in the motor noise signal; wherein the frequency of the constructed sound signal is the fundamental frequency
  • n and m are natural numbers and n is less than m.
  • the frequency ratio is 2:1 and the interval is octave, which belongs to the Concord interval.
  • Frequency ratio of other intervals small second degree 16:15, major second degree 9:8, small third degree 6:5, major third degree 5:4, pure fourth degree 4:3, increase four degrees 45:32, minus five degrees 64:45, pure 5 degrees 3:2, small sixth degree 8:5, big sixth degree 5:3, small seventh degree 16:9.
  • the intervals of complete harmony in music theory include pure one, pure eight, pure five, and pure four.
  • the subjective feeling of a fully consonant interval is best. Taking this as an example, when the second degree is small, the frequency of the constructed sound signal is the fundamental frequency.
  • the frequency of the constructed sound signal is the fundamental frequency
  • the frequency of the constructed sound signal is the fundamental frequency
  • the frequency of the constructed sound signal is the fundamental frequency
  • the frequency of the constructed sound signal is the fundamental frequency
  • the frequency of the constructed sound signal is the fundamental frequency
  • the frequency of the constructed sound signal is the fundamental frequency
  • the frequency of the constructed sound signal is the fundamental frequency
  • the frequency of the constructed sound signal is the fundamental frequency
  • the frequency of the constructed sound signal is the fundamental frequency
  • the fundamental frequency of the constructed sound signal is the fundamental frequency
  • the fundamental frequency of the constructed sound signal is the fundamental frequency
  • the fundamental frequency of the constructed sound signal is the fundamental frequency
  • K represents a slope of the frequency
  • a represents a constructed sound signal
  • A represents the harmonic coefficient
  • f represents the frequency at which the sound signal is constructed
  • t represents time.
  • Step S32 Constructing a sound signal adjusting step: adjusting the constructed sound signal according to the collected frequency of the non-motor noise in the acoustic ambient noise to generate the noise reduction structure signal.
  • the frequency of the structural sound signal generated in the above step S31 refers to the frequency of the structural sound signal generated in the above step S31 to remove the frequency of the non-motor noise repeated in the acoustic environment noise to generate the noise reduction structure signal.
  • the non-motor noise itself can function as a noise-reducing structure sound, and the non-motor noise can fuse the motor noise.
  • the function of noise reduction if the structure sound signal is generated again for playback, is actually redundant and repeated. Instead, extra low frequency noise is introduced.
  • the noise reduction structure signal takes into account the influence of non-motor noise, and can avoid non-motor noise components due to overlap, interference, etc.
  • the formation of a new enhanced noise signal leads to a problem of degraded acoustic environment quality.
  • the frequency of the acoustic environment noise collected in the acoustic environment collecting device includes 100 Hz, 200 Hz, 750 Hz, 800 Hz, 1000 Hz, 6000 Hz, etc., wherein 6000 Hz is the motor noise, and the motor noise of the 6000 Hz motor is required to be harmonically constructed, but In the existing non-motor noise, there is noise with a frequency of 750 Hz, which is his third-order subharmonic, so when it is generated, it is not necessary to generate a signal of this frequency.
  • the sound pressure level) value can be 0.
  • Step S4 the noise reduction structure signal conversion step: converting the noise reduction structure signal into a noise reduction frequency signal, and adjusting a sound pressure level of the noise reduction frequency signal according to a sound pressure level of the motor noise;
  • the noise reduction structure signal generated above is an analog signal, and cannot be directly played in the sound playback device, and must be converted into a digital signal (ie, a noise reduction frequency signal) before being input to the sound playback device for playback.
  • the sound pressure level should be adjusted to prevent the sound pressure level that determines the "no sound" from exceeding the range, resulting in new low frequency noise.
  • the sound pressure level of the noise reduction frequency signal is less than or equal to the sound pressure level of the collected motor noise, thereby playing the output noise reduction structure sound and the noise signal of the selected frequency band in the sound playback device. After the synthesis, the sound pressure level of the noise reduction structure sound has less influence on the sound pressure level of the fused sound.
  • the noise reduction frequency signal is a first-order subharmonic
  • the sound pressure level is half of the sound pressure level of the motor noise (not quantitative)
  • the sound pressure levels of other order subharmonics are based on the first order. According to this linear reduction.
  • the frequency of the motor noise is 4000 Hz
  • 2000 Hz, 1000 Hz, 500 Hz, 250 Hz is its octave harmonic
  • the first order is 4000 Hz, 2000 combined Hz
  • the second order is a combination of 4000 Hz, 2000 Hz, 1000 Hz, and so on.
  • Step S5 inputs the noise reduction frequency signal into the sound playing device for playing to output a noise reduction structure sound to perform noise reduction processing on the motor noise of the new energy vehicle.
  • the active noise reduction method of the new energy vehicle disclosed in this embodiment collects the frequency of the non-motor noise and the sound pressure level of the motor noise in the acoustic environment in real time. Acquiring the operating parameters of the new energy vehicle and the frequency of the non-motor noise and the sound pressure level of the motor noise; and further obtaining the frequency of the motor noise signal corresponding to the operating parameter, and simultaneously passing the non-motor according to the collected acoustic environment noise a frequency of the noise and a frequency of the obtained motor noise signal, generating a noise reduction structure signal; converting the noise reduction structure signal into a noise reduction frequency signal, and adjusting the voltage according to a sound pressure level of the motor noise The sound pressure level of the noise frequency signal; then the noise reduction frequency signal is input to the sound playback device for playback to output a noise reduction structure sound.
  • the noise reduction structure sound played by the sound playing device is combined with the acoustic environment noise, and the noise reduction structure signal is generated not only considering the frequency of the motor noise signal, but also comprehensively considering the sound of other non-motor noise and motor noise in the acoustic environment.
  • the magnitude of the pressure level avoids the problem that the structure signal generated by the frequency of a single motor noise signal is easily combined with other non-motor noise components to form a new enhanced noise signal due to overlap, interference, etc., resulting in a deterioration of the acoustic environment quality, thereby making it better.
  • Improve the quality of the acoustic environment The open and improved active noise reduction method can effectively solve the noise problem brought by the vehicle speed increase, and the method is easy to implement and simple and easy to operate.
  • the embodiment provides an active noise reduction system for a new energy vehicle, as shown in FIG. 7, including a sound environment noise collecting device 1, a noise reduction controller 2, and a sound playing device 3;
  • the acoustic environment noise collecting device 1 is configured to collect acoustic environment noise in an acoustic environment of a new energy vehicle, the acoustic environment noise including motor noise and non-motor noise;
  • the acoustic environment noise collecting device 1 is generally a microphone, and the microphone may be a device that is self-contained by the new energy vehicle itself, or may be a new microphone based on the original microphone of the original new energy vehicle.
  • the acoustic environment noise collecting device 1 is installed in a cab or a passenger's cab of a new energy vehicle. It mainly collects acoustic environment noise in the space where the cab and passengers are located.
  • the acoustic environment noise collecting device 1 is generally mounted on a center console in front of the cab and the passenger cab.
  • the acoustic environment noise collecting device 1 is connected to the CAN network and connected to the noise reduction controller 2 through the CAN network, so that the noise reduction controller 2 can read the collected from the acoustic environment noise collecting device 1 from the CAN network.
  • the data information includes the sound pressure level of the motor noise and the frequency of the non-motor noise that the noise reduction controller 2 needs to perform analysis processing.
  • the noise reduction controller 2 includes:
  • a data acquisition module 21 configured to acquire a frequency of the non-motor noise and a sound pressure level of the motor noise; and acquire an operation parameter of the new energy vehicle, and acquire, according to the operation parameter, the operation parameter a frequency of the motor noise signal; wherein the operating parameter includes at least a motor speed of the new energy vehicle;
  • the signal generating module 22 is configured to generate a noise reduction structure signal according to the collected frequency of the non-motor noise in the acoustic environment noise and the acquired frequency of the motor noise signal;
  • the signal conversion module 23 is configured to convert the noise reduction configuration signal into a noise reduction frequency signal, and adjust a sound pressure level of the noise reduction frequency signal according to a sound pressure level of the motor noise.
  • the sound playback device 3 is disposed in the new energy vehicle for inputting the noise reduction frequency signal into the sound playback device 3 for output to output a noise reduction structure sound to perform noise reduction processing on the motor noise of the new energy vehicle.
  • the signal conversion module 23 is a digital-to-analog conversion module, and converts the simulated noise reduction structure signal into a digital noise reduction frequency signal.
  • the sound playing device 3 may be an additionally arranged speaker device, which may be arranged in a passenger compartment where the driver or the passenger is located, such as on the center console of the cab and the passenger cab, or may also be sounded
  • the playing device 3 is arranged near the motor, that is, at the noise source, thereby ensuring the same path of the noise reduction structure sound and the motor noise signal, eliminating the uncertain factors such as the attenuation of the noise reduction structure sound during the propagation process, and improving the noise reduction.
  • the noise reduction effect of the built-in environment (ie, the acoustic environment) after the sound is combined with the motor noise signal.
  • it may be a speaker device that is included in the new energy vehicle itself.
  • the sound playback device 3 is a car audio system in a new energy vehicle.
  • the active noise reduction system of the new energy vehicle collects the frequency of non-motor noise and the sound pressure level of the motor noise in the acoustic environment in real time through the environmental noise collecting device. Obtaining the operating parameters of the new energy vehicle and the frequency of the non-motor noise and the sound pressure level of the motor noise through the noise reduction controller 2; thereby obtaining the frequency of the motor noise signal corresponding to the operating parameter, and simultaneously, according to the collected sound a frequency of the non-motor noise in the ambient noise and the obtained frequency of the motor noise signal, generating a noise reduction configuration signal; converting the noise reduction structure signal into a noise reduction frequency signal, and based on the sound pressure of the motor noise Level, adjusting the sound pressure level of the noise reduction frequency signal; then inputting the noise reduction frequency signal into the sound playback device 3 for playback to output a noise reduction construction sound.
  • the noise reduction structure sound played by the sound playback device 3 is fused with the acoustic environment noise, and the noise reduction structure signal is generated not only considering the frequency of the motor noise signal, but also comprehensively considering other non-motor noise and motor noise in the acoustic environment.
  • the magnitude of the sound pressure level avoids the problem that the sound generation environment is degraded by the frequency of the single motor noise signal, and the new non-motor noise component is easily overlapped and interfered with, resulting in a decrease in the acoustic environment quality. Good to improve the quality of the acoustic environment.
  • the improved active noise reduction system of the present disclosure can effectively solve the noise problem brought about by the increase of the vehicle speed, is convenient for the user to use, has low cost, and does not add an additional cost burden to the product.
  • this embodiment discloses a new energy vehicle 1000, which includes the active noise reduction system 100 disclosed in Embodiment 2 above. Since the active noise reduction system 100 of the new energy vehicle 1000 is only modified in this embodiment, and does not involve other structural and system improvements, the active noise reduction system 100 and its active noise reduction method have been performed in the above embodiments. Explain that in order to avoid repetition, it will not be repeated.
  • the new energy vehicle provided by the present disclosure has an active noise reduction system, and collects the frequency of non-motor noise and the sound pressure level of the motor noise in the acoustic environment in real time through the environmental noise collecting device. Obtaining the operating parameters of the new energy vehicle and the frequency of the non-motor noise and the sound pressure level of the motor noise through the noise reduction controller 2; thereby obtaining the frequency of the motor noise signal corresponding to the operating parameter, and simultaneously, according to the collected sound a frequency of the non-motor noise in the ambient noise and the obtained frequency of the motor noise signal, generating a noise reduction configuration signal; converting the noise reduction structure signal into a noise reduction frequency signal, and based on the sound pressure of the motor noise Level, adjusting the sound pressure level of the noise reduction frequency signal; then inputting the noise reduction frequency signal into the sound playback device 3 for playback to output a noise reduction construction sound.
  • the noise reduction structure sound played by the sound playback device 3 is fused with the acoustic environment noise, and the noise reduction structure signal is generated not only considering the frequency of the motor noise signal, but also comprehensively considering other non-motor noise and motor noise in the acoustic environment.
  • the magnitude of the sound pressure level avoids the problem that the sound generation environment is degraded by the frequency of the single motor noise signal, and the new non-motor noise component is easily overlapped and interfered with, resulting in a decrease in the acoustic environment quality. Good to improve the quality of the acoustic environment.
  • the improved active noise reduction system of the present disclosure can effectively solve the noise problem brought about by the increase of the vehicle speed, is convenient for the user to use, has low cost, and does not add an additional cost burden to the product.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Fittings On The Vehicle Exterior For Carrying Loads, And Devices For Holding Or Mounting Articles (AREA)

Abstract

为解决现有新能源车的主动降噪方法在进行电机噪声信号补偿的同时会与其他的非电机噪声产生干涉，形成新的加强的噪声信号，对改善声环境品质起到消极的作用问题，提供了一种新能源车及其主动降噪方法和系统。新能源车的主动降噪方法，生成降噪构造信号不仅考虑电机噪声信号的频率，还综合考虑声环境中的其他非电机噪声和电机噪声的声压级的大小。

Description

新能源车及其主动降噪方法和系统
相关公开的交叉引用
本公开要求比亚迪股份有限公司于2017年07月24日提交的、公开名称为“新能源车及其主动降噪方法和系统”的、中国专利公开号“201710605364.6”的优先权。
技术领域
本公开涉及噪声控制技术领域，具体涉及一种新能源车的主动降噪方法、一种新能源车的主动降噪系统和一种新能源车。
背景技术
随着新能源产业的迅速发展，也同样给我们带来了电机噪声的问题。尤其是新能源汽车，电机的高频噪声是一种噪声综合的结果，包括机械噪声，电磁噪声以及空气噪声，频率从1KHz到12KHz或者更高，这种高频的电磁噪声会给人带来强烈的不适感。所以对这种噪声的治理是非常有必要的。
相关的降噪方案主要有两种，一种是被动降噪，也叫做物理降噪。包括结构优化，消除共振，阻尼材料进行吸隔声等。另外一种是主动降噪，包括有源降噪和掩蔽效应以及其它一些声音补偿措施等手段。
其中，声音补偿是在原有的噪声的基础上添加其它的声音成分，来改变原有声音的特性(构造噪声，形成“和声噪音”)，这种方法的理论支撑来自于音乐声学，在音乐声学中，基频决定着音高，泛音决定音色。新能源车中的电机噪声之所以听起来如此刺耳，就是因为缺少泛音。所以我们需要构造的声音成分可以理解成是电机噪声的泛音。以此来达到提高环境声品质的目的。声音补偿的方法实现简单，在提高声品质时非常有效。
目前，效果较好的通过构造噪声进行主动降噪的方法如下：找出电机噪声信号的泛音成分，进行主观评价，选出那些主观评价高的泛音成分，储存备用，将电机噪声信号的相关特性与电机转速相关联，当电机转速为某一特定值时，调用相关的泛音成分，利用车载音响设备进行播放该泛音成分，如此，就能通过车载音响设备播放的泛音成分与电机噪声进行融合，以进行降噪处理。这在一定程度上能极大的提高电机噪声信号的声品质，改善驾乘体验。
但是本公开发明人在研发过程中发现，上述主动降噪方法仍然具备一定的缺陷，伴随 着车速的提升的同时，其他的非电机噪声的比例开始增加(路噪、胎噪、解构振动噪声等)，这样在进行电机噪声信号补偿的同时会与其他的非电机噪声产生干涉，形成新的特征信号，这些特征信号可能是加强的噪声信号，对改善声环境品质起到消极的作用。
发明内容
为解决现有新能源车伴随车速的提升的同时，其他的非电机噪声的比例开始增加，现有主动降噪方法在进行电机噪声信号补偿的同时会与其他的非电机噪声产生干涉，形成新的加强的噪声信号，对改善声环境品质起到消极的作用问题，本公开提供了一种新能源车及其主动降噪方法和系统。
本公开一方面提供了一种新能源车的主动降噪方法，包括如下步骤：
采集新能源车的声环境中的声环境噪声，所述声环境噪声包括电机噪声和非电机噪声；
获取所述非电机噪声的频率和所述电机噪声的声压级；并获取所述新能源车的运行参数，并根据所述运行参数获取与所述运行参数相关联的电机噪声信号的频率；其中，所述运行参数至少包括所述新能源车的电机转速；
根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；
控制将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；
将所述降噪音频信号输入声音播放装置中播放，以输出降噪构造声音，以对新能源车的电机噪声进行降噪处理。
本公开公开的新能源车的主动降噪方法，实时采集声环境中的非电机噪声的频率和电机噪声的声压级，并获取新能源车的运行参数以及非电机噪声的频率和电机噪声的声压级；进而获取与运行参数对应的电机噪声信号的频率，同时，通过根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；然后将所述降噪音频信号输入声音播放装置中播放，以输出降噪构造声音。由此，声音播放装置播放的降噪构造声音与声环境噪声进行融合，生成降噪构造信号不仅考虑电机噪声信号的频率，同时，还综合考虑声环境中的其他非电机噪声和电机噪声的声压级的大小，避免了仅凭单一电机噪声信号的频率生成构造信号容易与其它非电机噪声成分因重叠、干涉等形成新的加强的噪声信号，导致引起的声环境品质下降问题，从而更好的改善声环境品质。采用公开改进后的主动降噪方法，可有效的解决车速提升以后带来的噪声问题，该方法易于实现，简单易操作。
进一步地，所述“获取所述新能源车的运行参数”具体通过如下方式获得：读取所述新能源车的CAN总线传输的数据信息，以实现对所述运行参数的获取。
进一步地，所述“根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号”具体包括如下步骤：
根据所述电机噪声信号的频率通过调用预设的构造声音数据库以获取与所述电机噪声信号相对应的构造声音信号；或者，根据所述电机噪声信号的频率通过发生函数获得所述电机噪声信号相对应的构造声音信号；
根据采集到的所述声环境噪声中的非电机噪声的频率，对构造声音信号进行调节，生成所述降噪构造信号。
进一步地，所述“根据所述电机噪声信号的频率通过调用预设的构造声音数据库以获取与所述电机噪声信号相对应的构造声音信号”具体包括如下步骤：
根据所述电机噪声信号的频率判断所述电机噪声信号的所属频段；
根据所述电机噪声信号的所属频段调用所述预设的构造声音数据库，以获取与所述电机噪声信号的所属频段相对应的构造声音信号；其中，所述预设的构造声音数据库中存储有多个构造声音样本，每个构造声音样本对应一个噪声频段，且包括与该噪声频段相对应的构造声音信号。
进一步地，所述预设的构造声音数据库通过如下步骤获得：
获取不同工况下所述新能源车的运行参数，同时采集新能源车的电机噪声信号；
对所述电机噪声信号进行频谱分析以获取与所述运行参数相关联的噪声频谱特征信息，并根据所述噪声频谱特征信息建立所述运行参数与所述电机噪声信号的频率之间的对应关系；
根据所述噪声频谱特征信息对不同工况下的所述电机噪声进行频段划分以获得多个频段的标定噪声信号；
选择任一频段的标定噪声信号，并根据音乐声学或心理声学原理对所选频段的标定噪声信号进行频率构造以生成多个预选构造声音信号；
将所选频段的标定噪声信号分别与每个预选构造声音信号进行合成，以生成多个合成声音样本并输出，其中，每个合成声音样本的频率的所属频段均包括所述所选频段；
根据预设评价方法对每个合成声音样本进行评分，并根据每个合成声音样本的评分结果从所述预选构造声音信号中获取一个作为所选频段的标定噪声信号相对应的构造声音信号。
进一步地，所述“根据采集到的所述声环境噪声中的非电机噪声的频率，对构造声音信号进行调节，生成所述降噪构造信号”具体包括如下步骤：
将所述构造声音信号的频率去除所述声环境噪声中重复的非电机噪声的频率，以生成所述降噪构造信号。
进一步地，所述“根据所述电机噪声信号的频率通过发生函数获得所述电机噪声信号相对应的构造声音信号”具体包括如下步骤：
所述电机噪声信号包括基波和谐波，从所述电机噪声信号的频率中获得基波频率，并根据音乐声学或心理声学原理，通过发生函数获得所述构造声音信号，所述构造声音信号为所述电机噪声信号中基波的分谐波；其中，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000001
其中，n、m为自然数，n小于m。
进一步地，所述构造声音信号的发生函数表达式为：Y＝Ky+b，且y＝asin(2*π*A*f*t)；其中，K表示频率的斜率，a表示构造声音信号的振幅，A表示谐波系数，f表示构造声音信号的频率，t表示时间。
本公开第二方面提供了一种新能源车的主动降噪系统，包括：
声环境噪声采集装置，用于采集新能源车的声环境中的声环境噪声，所述声环境噪声包括电机噪声和非电机噪声；
降噪控制器，用于获取所述非电机噪声的频率和所述电机噪声的声压级；并获取所述新能源车的运行参数，并根据所述运行参数获取与所述运行参数相关联的电机噪声信号的频率；其中，所述运行参数至少包括所述新能源车的电机转速；并根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；然后控制将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；
声音播放装置，设置在新能源车内，用于输出降噪构造声音，以对新能源车的电机噪声进行降噪处理。
本公开提供的该新能源车的主动降噪系统，通过环境噪声采集装置实时采集声环境中的非电机噪声的频率和电机噪声的声压级。通过降噪控制器获取新能源车的运行参数以及非电机噪声的频率和电机噪声的声压级；进而获取与运行参数对应的电机噪声信号的频率，同时，通过根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；然后将所述降噪音频信号输入声音播放装置中播放，以输出降噪构造声音。由此，声音播放装置播放的降噪构造声音与声环境噪声进行融合，生成降噪构造信号不仅考虑电机噪声信号的频率，同时，还综合考虑声环境中的其他非电机噪声和电机噪声的声压级的大小，避免了仅凭单一电机噪声信号的频率生成构造信号容易与其它非电机噪声成分因重叠、干涉等形成新的加强的噪声信号，导 致引起的声环境品质下降问题，从而更好的改善声环境品质。采用本公开改进后的主动降噪系统，可有效的解决车速提升以后带来的噪声问题，方便用户使用，成本小，不会给产品增加额外的成本负担。
进一步地，所述降噪控制器具体包括：
数据获取模块，用于获取所述非电机噪声的频率和所述电机噪声的声压级；并获取所述新能源车的运行参数，并根据所述运行参数获取与所述运行参数相关联的电机噪声信号的频率；其中，所述运行参数至少包括所述新能源车的电机转速；
信号发生模块，用于根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；
信号转化模块，用于将所述降噪音频信号输入声音播放装置中播放，以输出降噪构造声音，以对新能源车的电机噪声进行降噪处理。
进一步地，所述信号转化模块为数模转换模块。
进一步地，所述声环境噪声采集装置设置在新能源车内。
进一步地，所述声音播放装置为新能源车内的车载音响。
本公开第三方面提供了一种新能源车，包括上述的主动降噪系统。
本公开提供的新能源车，由于具备主动降噪系统，其通过环境噪声采集装置实时采集声环境中的非电机噪声的频率和电机噪声的声压级。通过降噪控制器获取新能源车的运行参数以及非电机噪声的频率和电机噪声的声压级；进而获取与运行参数对应的电机噪声信号的频率，同时，通过根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；然后将所述降噪音频信号输入声音播放装置中播放，以输出降噪构造声音。由此，声音播放装置播放的降噪构造声音与声环境噪声进行融合，生成降噪构造信号不仅考虑电机噪声信号的频率，同时，还综合考虑声环境中的其他非电机噪声和电机噪声的声压级的大小，避免了仅凭单一电机噪声信号的频率生成构造信号容易与其它非电机噪声成分因重叠、干涉等形成新的加强的噪声信号，导致引起的声环境品质下降问题，从而更好的改善声环境品质。采用本公开改进后的主动降噪系统，可有效的解决车速提升以后带来的噪声问题，方便用户使用，成本小，不会给产品增加额外的成本负担。
附图说明
图1是本公开具体实施方式中提供的新能源车的主动降噪方法流程图；
图2是图1中步骤S3流程图；
图3是图2中步骤S31的一种具体实施例流程图；
图4是图3中步骤S312的一种具体实施例流程图；
图5是恒频啸叫频谱示意图；
图6是变频啸叫频谱示意图；
图7是本公开具体实施方式中提供的新能源车的主动降噪系统框图；
图8是本公开具体实施方式中提供的新能源车的主动降噪系统细化框图；
图9是本公开具体实施方式中提供的新能源车框图。
其中，1、声环境噪声采集装置；2、降噪控制器；3、声音播放装置；21、数据获取模块；22、信号发生模块；23、信号转化模块；100、主动降噪系统；1000、新能源车。
具体实施方式
为了使本公开所解决的技术问题、技术方案及有益效果更加清楚明白，以下结合附图及实施例，对本公开进行进一步详细说明。应当理解，此处所描述的具体实施例仅仅用以解释本公开，并不用于限定本公开。
实施例1
下面将结合附图1-图4对本公开公开的新能源车的主动降噪方法进行具体解释说明。
为使本领域技术人员充分理解本公开构思，先对本公开的主动降噪方法的基本原理进行具体解释说明。
本公开中的进行生成构造声音播放以对高频电机噪声进行降噪主要是利用心理声学和音乐声学的相关知识。在心理声学中，人耳对高频信号是比较不容易接受的，尤其是窄带的高频信号，更能极大的引起人们的烦躁感，甚至引起生理不适(晕车、恶心)。但是当这种高频的噪声信号与其它频率成分组成新的声音信号时，人们却又非常乐意接受，一个有趣的例子是，我们非常喜欢歌唱家的高音，却很难去接受金属物体划过玻璃时的“吱吱”声，虽然两者的中心频率可能相差无几。
在音乐声学中，我们听见的声音(同样包括噪音)是由两部分组成的，基波和谐波(泛音)，通常谐波的频率(为区别起见，简称谐波频率)是基波的频率(为区别期间，简称基频)成分的整数倍。基频决定着音高，谐波频率决定音色，音高是决定这个声音“响不响”，音色来决定声音“美不美”。这样就可以解释歌唱家的高音和金属物体划过玻璃时的“吱吱”声虽然中心频率相近，但主观感受却天壤之别的原因，两者的泛音不同。
在新能源车中，电机噪声的频率一般都会很高，如果完全按照音乐声学的原理来构造它的谐波成分的话，可能主观感受会有所提高，但由于高频成分的增加，烦躁度也会增加， 不能达到提高环境声品质的目的。于是我们反向思考，加入高频信号的分数谐波(简称分谐波)成分，构造机理依然是音乐声学的相关原理。在主观感受中加入分数谐波和加入谐波的效果是一样的，都可以提高声品质，他们在物理机制中的解释也是一样的，也就是两个信号重合的几率是一样的，比如，基频为5000Hz，谐波频率是10000Hz，谐波每振动两次就有一次是跟基频重合的，谐波频率与基频的频率比为2:1；基频为5000Hz，分谐波成分是2500Hz，基频每振动两次就有一次跟分谐波重合，基频与谐波频率的频率比是2:1；两者是一样的。在心理声学中，当我们加入电机高频信号的分谐波时，在整个频域之中高频成分所占有的比值就会降低，而高频成分的多少反映了烦躁度的大小，所以烦躁度是降低的。
同时，当加入分谐波信号时，如果声压级过大，那么，其同样可能变成引入的新的噪声，因此，为了使分谐波起到与高频的电机噪声相融合以实现降噪的目的，需要将分谐波的声压级控制在合适的范围内。所谓声压级(sound pressure level)是表征声压大小的指标，声压是大气压受到声波扰动后产生的变化，即为大气压强的余压，它相当于在大气压强上的叠加一个声波扰动引起的压强变化。声波通过媒质时，由于振动所产生的压强改变量。它是随时间变化的，实测声压是它的有效值。单位是帕斯卡(Pa)。声压级用某声音的声压P与基本声压值P0之比的常用对数的20倍来表示，即20lg P/P0，单位为分贝(dB)。
本实施例提供了一种新能源车的主动降噪方法，包括如下步骤：
步骤S1、声环境噪声采集步骤：采集新能源车的声环境中的声环境噪声，所述声环境噪声包括电机噪声和非电机噪声；
其中，所谓声环境指在一定的区域中，所有声音组成的系统，所谓新能源车的声环境指新能源车内部环境，具体的，本实施例中指驾驶员和乘客所处的空间中，比如驾驶室内(或者置于副驾驶室内，效果也是等效的)。
所谓的声环境噪声，指在声环境中为驾驶员或乘客感受到的噪声，具体通过实施例2中所说的声环境噪声采集装置进行采集。一方面，该声环境噪声包括来源于电机的高频噪声，将其称为电机噪声。通过对新能源车的高频电机噪声的研究，我们发现，当电机转速达到一定的值时，会产生啸叫声，这种啸叫声的频率总体上可以分为两类，一类是频率不变的，我们称之为恒频啸叫，另一类是变频的，我们称之为变频啸叫。上述两种啸叫均是高频的电机噪声。另一方面，还包括其他非电机噪声，比如路噪、胎噪、解构振动噪声等，这些非电机噪声的频率相对较低。
同时，噪声也属于声音，表征该声环境噪声的参数也包括频率、声压级等。本实施例中，主要通过采集电机噪声的声压级和其他非电机噪声的频率，以供后续生成降噪构造信号和调整降噪构造信号的声压级，使之在声音播放装置中播放出合理的可以与电机噪声相 融合的降噪构造声音，以实现主动降噪的目的。
步骤S2、数据获取步骤：获取所述非电机噪声的频率和所述电机噪声的声压级；并获取所述新能源车的运行参数，并根据所述运行参数获取与所述运行参数相关联的电机噪声信号的频率；其中，所述运行参数至少包括所述新能源车的电机转速。
在本公开的实施例中，可以通过读取新能源车的CAN总线传输的数据信息以实现对运行参数的采集。可选地，新能源车的运行参数还可以包括新能源车的车速、油门开度等。
具体地，可以预先存储电机转速与其电机噪声信号的频率之间的关系。在采集运行参数时，可以接入新能源车的CAN总线，通过读取新能源车的CAN总线传输的数据，即可得到电机转速、车速、油门开度等运行参数。进而可以通过CAN总线获取预先存储的电机转速与电机噪声信号的频率之间的关系，根据电机转速从中获取对应的电机噪声信号的频率。
具体地，以运行参数为电机转速为例进行说明。在不同的工况下，可以采集新能源车的电机转速和该电机转速对应的电机噪声信号；然后可以通过频谱分析仪对采集的电机噪声信号进行频域分析，以获得电机噪声信号的频谱特征信息，如频率和声压级；进而可得到电机转速与电机噪声信号的频率和声压级之间的对应关系。
步骤S1中采集到的声环境噪声的参数可通过CAN总线传输，同样的，也可以通过读取新能源车的CAN总线传输的数据信息以实现对所述非电机噪声的频率和所述电机噪声的声压级的采集。
步骤S3、降噪构造信号生成步骤：根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号。
本实施例中，该降噪构造信号生成步骤与现有仅通过单一电机噪声信号频率生成的方法，更具优势，其可以通过声环境噪声中非电机噪声的频率进一步对其进行调控，以使其生成的降噪构造信号更加合理。避免了仅凭单一电机噪声信号的频率生成构造信号容易与其它非电机噪声成分因重叠、干涉等形成新的加强的噪声信号，导致引起的声环境品质下降问题，从而更好的改善声环境品质。
其中，如图2所示，该步骤S3具体通过如下步骤实现：
步骤S31、构造声音信号获取步骤：根据所述电机噪声信号的频率通过调用预设的构造声音数据库以获取与所述电机噪声信号相对应的构造声音信号；或者，根据所述电机噪声信号的频率通过发生函数获得所述电机噪声信号相对应的构造声音信号。
本步骤S31中，可以通过上述两种方式获取。下面对其一一进行解释说明。
第一种构造声音信号获取方式：根据所述电机噪声信号的频率通过调用预设的构造声音数据库以获取与所述电机噪声信号相对应的构造声音信号具体通过图3中步骤获得。
步骤S311：根据所述电机噪声信号的频率判断所述电机噪声信号的所属频段；
步骤S312：根据所述电机噪声信号的所属频段调用所述预设的构造声音数据库，以获取与所述电机噪声信号的所属频段相对应的构造声音信号；其中，所述预设的构造声音数据库中存储有多个构造声音样本，每个构造声音样本对应一个噪声频段，且包括与该噪声频段相对应的构造声音信号。
具体地，在一个示例中，如果通过电机转速获取到的电机噪声信号的频率取值为4000-5000Hz，即为高频信号，则可以通过CAN总线调用预设的构造声音数据库，从中可以获取与该高频信号相对应的构造声音信号，如600-1000Hz的低频的构造声音信号。
其中，该步骤S312中的构造声音数据库需要预先通过图4所示步骤获得：
步骤S3121：获取不同工况下所述新能源车的运行参数，同时采集新能源车的电机噪声信号；此处采集新能源车的电机噪声信号不同于上述声环境采集装置中采集的电机噪声。
声环境采集装置采集的噪音不仅包括电机噪声，还包括非电机噪声，因此，其对于电机噪声的要求是相对较低的，虽然也可以通过该电机转速与电机噪声的频率建立对应关系，但是其精度不高。因此，声环境采集装置中采集到的各种参数中，我们后续用的是电机噪声的声压级和其他非电机噪声的频率。并没有使用该电机噪声的频率用于降噪构造信号的生成。
对电机高频噪声的采集必须要精确一点，如果用噪声装置对电机噪声进行采集的话，同时会采集到其它非电机高频噪声，比如车体摩擦噪声、喇叭声、车外噪声等，会对降噪构造信号产生影响。该电机噪声信号的频率和电机转速是这样建立对应关系的，可以直接在电机附近(布置电机的电机仓中)采集该电机噪声信号，由此可以保证采集到的电机噪声信号的完整性，排除噪声在传播过程中产生的衰减等不确定因素。并防止其他非电机噪声进行干扰。具体地，可以通过声音信号接收器(如麦克风等)中转速传感器的一种或者组合实时采集电机产生的噪声。对于负载比较恒定的电机，可以只用转速传感器采集噪声；对于负载变化较大的电机，可以通过转速传感器和声音信号接收器同时采集噪声，以提高噪声的采集精度。
步骤S3122：对所述电机噪声信号进行频谱分析以获取与所述运行参数相关联的噪声频谱特征信息，并根据所述噪声频谱特征信息建立所述运行参数与所述电机噪声信号的频率之间的对应关系；
具体地，以运行参数为电机转速为例进行说明。在不同的工况下，可以采集新能源车的电机转速和该电机转速对应的电机噪声信号；然后可以通过频谱分析仪对采集的电机噪声信号进行频域分析，以获得电机噪声信号的频谱特征信息，如频率和声压级；进而可得到电机转速与电机噪声信号的频率和声压级之间的对应关系。
步骤S3123：根据所述噪声频谱特征信息对不同工况下的所述电机噪声信号进行频段划分以获得多个频段的标定噪声信号；
具体地，可以根据电机转速将电机噪声信号的频率分为高频、低频、恒频、变频等。可以理解，电机转速较大时，可以是对应高频噪声；电机转速较小时，可以是对应低频噪声；电机转速变化较小，即基本恒定时，可以是对应恒频噪声；电机转速逐渐增加，即有加速度、且加速度大于一定值时，可以是对应变频噪声。
其中，对电机噪声信号进行频段划分是为了在进行频率构造时节省工作量。例如，车内环境噪声中的高频成分会有比较强烈的尖锐感，在进行频率构造时可以适当添加低频成分，以增加较多中间频率成分。
举例而言，电机噪声信号的频率为高频，如3000-6000Hz时，可以构造600-1000Hz的声音以增加至该高频噪声中。
步骤S3124：选择任一频段的标定噪声信号，并根据音乐声学或心理声学原理对所选频段的标定噪声信号进行频率构造以生成多个预选构造声音信号；
具体地，对于任一频段的标定噪声信号，可以根据音乐声学或心理声学原理利用声音处理软件(如MATLAB)对该频段的噪声信号进行频率构造以生成多个构造声音信号。
步骤S3125：将所选频段的标定噪声信号分别与每个预选构造声音信号进行合成，以生成多个合成声音样本并输出，其中，每个合成声音样本的频率的所属频段均包括所述所选频段；
其中，每个合成声音样本的频率的所属频段均包括所选频段。例如，对于4000-5000Hz频段的噪声信号，进行频率构造后得到400-500Hz频段的低频信号，两者合成后得到的合成声音样本的频率的所属频段可以为400-6000Hz，可见，400-6000Hz频段包括4000-5000Hz频段。由此，通过构造声音信号可以对所选频段的噪声信号的频率进行补偿，即使得合成声音样本的频率覆盖范围广。
步骤S3126：根据预设评价方法对每个合成声音样本进行评分，并根据每个合成声音样本的评分结果从所述预选构造声音信号中获取一个作为所选频段的标定噪声信号相对应的构造声音信号。
其中，预设评价方法可以包括：1)确定评价人员，评价人员应具有正常的听觉，可以是一般的工作人员，人数可以要求在10人以上；2)评分标准，可以采用百分制进行评分，同时采用五级评价标准，如，优：很悦耳(如，听起来令人舒服、平静、愉悦)(80-100分)，良：悦耳(60-80分)，中：一般40-60分)，差：难听(20-40分)，劣：很难听(如，听起来令人不舒服、令人不安、烦躁等)(0-20分)，即评价人员可以基于分级评价进行百分制评分；3)试听条件，如可以在较为安静的室内环境中进行试听评价。
举例而言，由男女成年人各10人组成评价人员，在较为安静的室内环境中，播放所选频段对应的每个合成声音样本，每个合成声音样本可以播放3遍。在播放3遍后，由20个评价人员进行评分，评分完成后，对评分结果进行数理统计，以选出评分最高(如，平均分最高)的合成声音样本，将该合成声音样本对应的预选构造声音样本作为与所选频段的噪声信号相对应的构造声音样本。同理，可以获取每个频段的噪声信号对应的构造声音样本，所有构造声音样本的集合即为上述预设的构造声音数据库。
第二种构造声音获取方式描述如下：
所述电机噪声信号包括基波和谐波，从所述电机噪声信号的频率中获得基波频率，并根据音乐声学或心理声学原理，通过发生函数获得所述构造声音信号，所述构造声音信号为所述电机噪声信号中基波的分谐波；其中，所述构造声音信号的频率为所述基频的的
Figure PCTCN2018089323-appb-000002
其中，n、m为自然数，n小于m。比如，在音乐声学中频率比是2:1的音程为八度，属于协和音程。其他音程的频率比：小二度16:15，大二度9:8，小三度6:5，大三度5:4，纯四度4:3，增四度45:32，减五度64:45，纯五度3:2，小六度8:5，大六度5:3，小七度16:9。乐理中完全协和的音程包括纯一、纯八、纯五、纯四。完全协和音程的主观感受最佳。依此为例，小二度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000003
大二度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000004
小三度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000005
大三度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000006
纯四度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000007
增四度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000008
减五度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000009
纯五度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000010
小六度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000011
大六度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000012
小七度时，所述构造声音信号的频率为所述基频的
Figure PCTCN2018089323-appb-000013
进一步地，所述构造声音信号的发生函数表达式为：Y＝Ky+b，且y＝asin(2*π*A*f*t)；其中，K表示频率的斜率，a表示构造声音信号的振幅，A表示谐波系数，f表示构造声音信号的频率，t表示时间。当电机噪声为恒频啸叫时，举例说明，如图5所示，我们知道了电机啸叫的一个恒定频率为f＝5050Hz，假设此信号为正弦信号。通过研究发现，对于这一频率的电机信号构造，构造八度音程谐波成分的主观感受最好，于是我们就要生成频率为f/2＝2525Hz的正弦信号作为降噪构造信号。其中，K为1，b为0。如果我们知道的电机啸叫是如图6所示的一个从3500Hz到4300Hz线性递增的频率，那么此时的发生函数即为上述的线性渐变的函数。
步骤S32、构造声音信号调节步骤：根据采集到的所述声环境噪声中的非电机噪声的频率，对构造声音信号进行调节，生成所述降噪构造信号。
具体的，指上述步骤S31中生成的构造声音信号的频率去除所述声环境噪声中重复的 非电机噪声的频率，以生成所述降噪构造信号。其原因是当非电机噪声中的低频信号与构造声音信号相重合时，此时，实际上非电机噪声本身可以起到降噪构造声音的作用，该非电机噪声即可对电机噪声起到融合降噪的功能，如果再生成该构造声音信号进行播放，实际上是多余、重复的了。反而引入了多余的低频噪声。因此，需要利用该非电机噪声的频率对构造声音信号进行调节，生成所述降噪构造信号；该降噪构造信号考虑了非电机噪声的影响，可以避免出现非电机噪声成分因重叠、干涉等形成新的加强的噪声信号，导致引起的声环境品质下降问题。例如，声环境采集装置中采集到的声环境噪声的频率包括100Hz、200Hz、750Hz、800Hz、1000Hz、6000Hz等，其中，6000Hz即为电机噪声，需要对该6000Hz的电机噪声进行和声构造，但是在已有非电机噪声中存在频率为750Hz的噪声，是他的3阶分谐波，所以在产生时，就不需要再产生这一频率的信号了。在程序上的实现也不难，只要将发生函数y＝asin(2*π*A*f*t)中的分谐波振幅a(该分谐波振幅的大小决定了声音的响度，响度对应声压级)值赋0即可。
步骤S4、降噪构造信号转化步骤：将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；
上述生成的降噪构造信号，是模拟信号，还不能直接在声音播放装置中进行播放，必须转化成数字信号(即降噪音频信号)才可输入声音播放装置中播放。同时，也要对其声压级进行调节，防止决定“响不响”的声压级超出范围，产生新的低频噪声。
在本公开的实施例中，降噪音频信号的声压级小于等于采集到的电机噪声的声压级，由此，在声音播放装置中播放输出的降噪构造声音与所选频段的噪声信号进行合成后，降噪构造声音的声压级对融合后的声音的声压级的影响较小。
比如，如果该降噪音频信号为一阶分谐波，则其声压级是电机噪声的声压级的一半(不是定量)，其他阶次分谐波的声压级在一阶的基础上依此线性减小。如果电机噪声的频率是4000Hz，那么2000Hz、1000Hz、500Hz、250Hz是它的八度谐波，一阶就是4000Hz、2000组合Hz，二阶是4000Hz、2000Hz、1000Hz的组合，以此类推。
在程序中的实现为，调整y＝asin(2*π*A*f*t)中的a值为噪声的一半，其他在a的基础上线性减小。
比如我们知道了电机噪声的声压级为A，则构造八度分谐波和声信号用作降噪构造信号，我们需要一阶的分谐波信号的声压级为A/2，所以在生成降噪音频信号时，就要自动调节发生函数y＝asin(2*π*A*f*t)中的构造声音信号的振幅a。
步骤S5将所述降噪音频信号输入声音播放装置中播放，以输出降噪构造声音，以对新能源车的电机噪声进行降噪处理。
本实施例公开的新能源车的主动降噪方法，实时采集声环境中的非电机噪声的频率和 电机噪声的声压级。获取新能源车的运行参数以及非电机噪声的频率和电机噪声的声压级；进而获取与运行参数对应的电机噪声信号的频率，同时，通过根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；然后将所述降噪音频信号输入声音播放装置中播放，以输出降噪构造声音。由此，声音播放装置播放的降噪构造声音与声环境噪声进行融合，生成降噪构造信号不仅考虑电机噪声信号的频率，同时，还综合考虑声环境中的其他非电机噪声和电机噪声的声压级的大小，避免了仅凭单一电机噪声信号的频率生成构造信号容易与其它非电机噪声成分因重叠、干涉等形成新的加强的噪声信号，导致引起的声环境品质下降问题，从而更好的改善声环境品质。采用公开改进后的主动降噪方法，可有效的解决车速提升以后带来的噪声问题，该方法易于实现，简单易操作。
实施例2
本实施例提供了一种新能源车的主动降噪系统，如图7所示，包括声环境噪声采集装置1、降噪控制器2和声音播放装置3；
声环境噪声采集装置1用于采集新能源车的声环境中的声环境噪声，所述声环境噪声包括电机噪声和非电机噪声；
该声环境噪声采集装置1一般为麦克风，该麦克风可以为新能源车本身自带的装置，也可以为在原有新能源车自带麦克风的基础上，新增的麦克风。所述声环境噪声采集装置1设置在新能源车的驾驶室或副驾驶室内。主要采集驾驶室和乘客所在空间中的声环境噪声。比如，一般将该声环境噪声采集装置1安装在驾驶室和副驾驶室前的中控台上。
该声环境噪声采集装置1连接到CAN网络，并通过CAN网络连接到降噪控制器2，使降噪控制器2可以从CAN网络上读取到所述声环境噪声采集装置1中采集到的数据信息。该数据信息中包括降噪控制器2需要进行分析处理的电机噪声的声压级和非电机噪声的频率。
具体的，如图8所示，所述降噪控制器2包括：
数据获取模块21，用于获取所述非电机噪声的频率和所述电机噪声的声压级；并获取所述新能源车的运行参数，并根据所述运行参数获取与所述运行参数相关联的电机噪声信号的频率；其中，所述运行参数至少包括所述新能源车的电机转速；
信号发生模块22，用于根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；
信号转化模块23，用于将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪 声的声压级，调节所述降噪音频信号的声压级。
声音播放装置3设置在新能源车内，用于将所述降噪音频信号输入声音播放装置3中播放，以输出降噪构造声音，以对新能源车的电机噪声进行降噪处理。
其中，本实施例中，所述信号转化模块23为数模转换模块，将模拟的降噪构造信号转化为数字的降噪音频信号。
其中，该声音播放装置3可以为额外布置的扬声设备，其可以布置在驾驶员或者乘客所在的乘员仓中，比如驾驶室和副驾驶室内的中控台上，或者，也可将其声音播放装置3布置在电机附近，即噪声源处，由此可以保证降噪构造声音和电机噪声信号同源同途径，消除降噪构造声音在传播过程中产生的衰减等不确定因素，提高降噪构造声音与电机噪声信号进行融合后对车内环境(即声环境)的降噪效果。或者也可为新能源车内本身自带的扬声设备，比如所述声音播放装置3为新能源车内的车载音响。
需要说明的是，本实施例的新能源车的主动降噪系统的其它具体实施方式可参见本公开上述实施例的新能源车的主动降噪方法的具体实施方式，为减少冗余，此处不做赘述。
本公开提供的该新能源车的主动降噪系统，通过环境噪声采集装置实时采集声环境中的非电机噪声的频率和电机噪声的声压级。通过降噪控制器2获取新能源车的运行参数以及非电机噪声的频率和电机噪声的声压级；进而获取与运行参数对应的电机噪声信号的频率，同时，通过根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；然后将所述降噪音频信号输入声音播放装置3中播放，以输出降噪构造声音。由此，声音播放装置3播放的降噪构造声音与声环境噪声进行融合，生成降噪构造信号不仅考虑电机噪声信号的频率，同时，还综合考虑声环境中的其他非电机噪声和电机噪声的声压级的大小，避免了仅凭单一电机噪声信号的频率生成构造信号容易与其它非电机噪声成分因重叠、干涉等形成新的加强的噪声信号，导致引起的声环境品质下降问题，从而更好的改善声环境品质。采用本公开改进后的主动降噪系统，可有效的解决车速提升以后带来的噪声问题，方便用户使用，成本小，不会给产品增加额外的成本负担。
实施例3
如图9所示，本实施例公开了一种新能源车1000，包括上述实施例2中公开的主动降噪系统100。因本实施例中仅对新能源车1000的主动降噪系统100进行改进，而不涉及其他结构和系统的改进，且该主动降噪系统100及其主动降噪方法已在上述实施例中进行说明，为免重复，不再赘述。
本公开提供的新能源车，由于具备主动降噪系统，其通过环境噪声采集装置实时采集声环境中的非电机噪声的频率和电机噪声的声压级。通过降噪控制器2获取新能源车的运行参数以及非电机噪声的频率和电机噪声的声压级；进而获取与运行参数对应的电机噪声信号的频率，同时，通过根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；然后将所述降噪音频信号输入声音播放装置3中播放，以输出降噪构造声音。由此，声音播放装置3播放的降噪构造声音与声环境噪声进行融合，生成降噪构造信号不仅考虑电机噪声信号的频率，同时，还综合考虑声环境中的其他非电机噪声和电机噪声的声压级的大小，避免了仅凭单一电机噪声信号的频率生成构造信号容易与其它非电机噪声成分因重叠、干涉等形成新的加强的噪声信号，导致引起的声环境品质下降问题，从而更好的改善声环境品质。采用本公开改进后的主动降噪系统，可有效的解决车速提升以后带来的噪声问题，方便用户使用，成本小，不会给产品增加额外的成本负担。
以上所述仅为本公开的较佳实施例而已，并不用以限制本公开，凡在本公开的精神和原则之内所作的任何修改、等同替换和改进等，均应包含在本公开的保护范围之内。

Claims (14)

  1. 一种新能源车的主动降噪方法，其特征在于，包括如下步骤：
    采集新能源车的声环境中的声环境噪声，所述声环境噪声包括电机噪声和非电机噪声；
    获取所述非电机噪声的频率和所述电机噪声的声压级；并获取所述新能源车的运行参数，并根据所述运行参数获取与所述运行参数相关联的电机噪声信号的频率；其中，所述运行参数至少包括所述新能源车的电机转速；
    根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；
    将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；
    将所述降噪音频信号输入声音播放装置中播放，以输出降噪构造声音，以对新能源车的电机噪声进行降噪处理。
  2. 根据权利要求1所述的新能源车的主动降噪方法，其特征在于，所述“获取所述新能源车的运行参数”具体通过如下方式获得：读取所述新能源车的CAN总线传输的数据信息，以实现对所述运行参数的获取。
  3. 根据权利要求1或2所述的新能源车的主动降噪方法，其特征在于，所述“根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号”具体包括如下步骤：
    根据所述电机噪声信号的频率通过调用预设的构造声音数据库以获取与所述电机噪声信号相对应的构造声音信号；或者，根据所述电机噪声信号的频率通过发生函数获得所述电机噪声信号相对应的构造声音信号；
    根据采集到的所述声环境噪声中的非电机噪声的频率，对构造声音信号进行调节，生成所述降噪构造信号。
  4. 根据权利要求3所述的新能源车的主动降噪方法，其特征在于，所述“根据所述电机噪声信号的频率通过调用预设的构造声音数据库以获取与所述电机噪声信号相对应的构造声音信号”具体包括如下步骤：
    根据所述电机噪声信号的频率判断所述电机噪声信号的所属频段；
    根据所述电机噪声信号的所属频段调用所述预设的构造声音数据库，以获取与所述电 机噪声信号的所属频段相对应的构造声音信号；其中，所述预设的构造声音数据库中存储有多个构造声音样本，每个构造声音样本对应一个噪声频段，且包括与该噪声频段相对应的构造声音信号。
  5. 根据权利要求4所述的新能源车的主动降噪方法，其特征在于，所述预设的构造声音数据库通过如下步骤获得：
    获取不同工况下所述新能源车的运行参数，同时采集新能源车的电机噪声信号；
    对所述电机噪声信号进行频谱分析以获取与所述运行参数相关联的噪声频谱特征信息，并根据所述噪声频谱特征信息建立所述运行参数与所述电机噪声信号的频率之间的对应关系；
    根据所述噪声频谱特征信息对不同工况下的所述电机噪声信号进行频段划分以获得多个频段的标定噪声信号；
    选择任一频段的标定噪声信号，并根据音乐声学或心理声学原理对所选频段的标定噪声信号进行频率构造以生成多个预选构造声音信号；
    将所选频段的标定噪声信号分别与每个预选构造声音信号进行合成，以生成多个合成声音样本并输出，其中，每个合成声音样本的频率的所属频段均包括所述所选频段；
    根据预设评价方法对每个合成声音样本进行评分，并根据每个合成声音样本的评分结果从所述预选构造声音信号中获取一个作为所选频段的标定噪声信号相对应的构造声音信号。
  6. 根据权利要求3至5中任意一项所述的新能源车的主动降噪方法，其特征在于，所述“根据采集到的所述声环境噪声中的非电机噪声的频率，对构造声音信号进行调节，生成所述降噪构造信号”具体包括如下步骤：
    将所述构造声音信号的频率去除所述声环境噪声中重复的非电机噪声的频率，以生成所述降噪构造信号。
  7. 根据权利要求3至6中任意一项所述的新能源车的主动降噪方法，其特征在于，所述“根据所述电机噪声信号的频率通过发生函数获得所述电机噪声信号相对应的构造声音信号”具体包括如下步骤：
    所述电机噪声信号包括基波和谐波，从所述电机噪声信号的频率中获得基波频率，并根据音乐声学或心理声学原理，通过发生函数获得所述构造声音信号，所述构造声音信号为所述电机噪声信号中基波的分谐波；其中，所述构造声音信号的频率为所述基波频率的，
    Figure PCTCN2018089323-appb-100001
    其中，n、m为自然数，n小于m。
  8. 根据权利要求7所述的新能源车的主动降噪方法，其特征在于，所述构造声音信号的发生函数表达式为：Y＝Ky+b，且y＝asin(2*π*A*f*t)；其中，K表示频率的斜率，a表示构造声音信号的振幅，A表示谐波系数，f表示构造声音信号的频率，t表示时间。
  9. 一种新能源车的主动降噪系统，其特征在于，包括：
    声环境噪声采集装置，用于采集新能源车的声环境中的声环境噪声，所述声环境噪声包括电机噪声和非电机噪声；
    降噪控制器，用于获取所述非电机噪声的频率和所述电机噪声的声压级；并获取所述新能源车的运行参数，并根据所述运行参数获取与所述运行参数相关联的电机噪声信号的频率；其中，所述运行参数至少包括所述新能源车的电机转速；并根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；然后控制将所述降噪构造信号转化为降噪音频信号，并根据所述电机噪声的声压级，调节所述降噪音频信号的声压级；
    声音播放装置，设置在新能源车内，用于输出降噪构造声音，以对新能源车的电机噪声进行降噪处理。
  10. 根据权利要求9所述的新能源车的主动降噪系统，其特征在于，所述降噪控制器具体包括：
    数据获取模块，用于获取所述非电机噪声的频率和所述电机噪声的声压级；并获取所述新能源车的运行参数，并根据所述运行参数获取与所述运行参数相关联的电机噪声信号的频率；其中，所述运行参数至少包括所述新能源车的电机转速；
    信号发生模块，用于根据采集到的所述声环境噪声中的非电机噪声的频率和获取到的所述电机噪声信号的频率，生成降噪构造信号；
    信号转化模块，用于将所述降噪音频信号输入声音播放装置中播放，以输出降噪构造声音，以对新能源车的电机噪声进行降噪处理。
  11. 根据权利要求10所述的新能源车的主动降噪系统，其特征在于，所述信号转化模块为数模转换模块。
  12. 根据权利要求11所述的新能源车的主动降噪系统，其特征在于，所述声环境噪声 采集装置设置在新能源车内。
  13. 根据权利要求11或12所述的新能源车的主动降噪系统，其特征在于，所述声音播放装置为新能源车内的车载音响。
  14. 一种新能源车，其特征在于，包括权利要求9-13中任意一项所述的新能源车的主动降噪系统。
PCT/CN2018/089323 2017-07-24 2018-05-31 新能源车及其主动降噪方法和系统 WO2019019801A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201710605364.6 2017-07-24
CN201710605364.6A CN109300465B (zh) 2017-07-24 2017-07-24 新能源车及其主动降噪方法和系统

Publications (1)

Publication Number Publication Date
WO2019019801A1 true WO2019019801A1 (zh) 2019-01-31

Family

ID=65039373

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2018/089323 WO2019019801A1 (zh) 2017-07-24 2018-05-31 新能源车及其主动降噪方法和系统

Country Status (2)

Country Link
CN (1) CN109300465B (zh)
WO (1) WO2019019801A1 (zh)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111723415A (zh) * 2020-06-15 2020-09-29 中科上声（苏州）电子有限公司 一种车辆降噪系统的性能评估方法及装置
CN111798831A (zh) * 2020-06-16 2020-10-20 武汉理工大学 一种声音粒子合成方法及装置
CN112185335A (zh) * 2020-09-27 2021-01-05 上海电气集团股份有限公司 一种降噪方法、装置、电子设备及存储介质

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110942762A (zh) * 2019-12-06 2020-03-31 苏州市华音电子科技有限公司 一种对车辆进行分频段消噪的控制方法及系统
CN111210801B (zh) * 2020-02-25 2022-08-02 北京绿创声学工程股份有限公司 一种有调噪声补偿消除方法及系统
CN113299305A (zh) * 2021-05-21 2021-08-24 昆山宝创新能源科技有限公司 汽车断路盒降噪方法、装置、电子设备及存储介质
CN114275918B (zh) * 2021-12-07 2023-01-24 佛山市美的清湖净水设备有限公司 净水机及其噪音改善方法
CN116092465B (zh) * 2023-03-31 2023-06-23 彩讯科技股份有限公司 一种车载音频降噪方法、装置、存储介质和电子设备
CN117713633B (zh) * 2024-02-02 2024-04-19 深圳市艾普希隆科技有限公司 用于伺服电机的变频控制调节方法及系统

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7203321B1 (en) * 1999-09-21 2007-04-10 Bayerische Motoren Werke Aktiengesellschaft Device for electroacoustic sound generation in a motor vehicle
CN104616667A (zh) * 2014-12-02 2015-05-13 清华大学 一种用于汽车内的主动降噪方法
CN104908688A (zh) * 2015-05-20 2015-09-16 浙江吉利汽车研究院有限公司 车辆主动降噪的方法及装置
CN105263088A (zh) * 2015-10-21 2016-01-20 莆田市云驰新能源汽车研究院有限公司 一种汽车降噪方法及系统
CN106382143A (zh) * 2016-12-01 2017-02-08 吉林大学 一种基于发动机转速的主动降噪装置及方法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1947642B1 (en) * 2007-01-16 2018-06-13 Apple Inc. Active noise control system
US10288474B2 (en) * 2013-06-21 2019-05-14 Brüel & Kjær Sound & Vibration Measurement A/ S Method of determining noise sound contributions of noise sources of a motorized vehicle
CN106933146B (zh) * 2017-03-14 2023-04-14 吉林大学 电动轿车行人警示音控制方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7203321B1 (en) * 1999-09-21 2007-04-10 Bayerische Motoren Werke Aktiengesellschaft Device for electroacoustic sound generation in a motor vehicle
CN104616667A (zh) * 2014-12-02 2015-05-13 清华大学 一种用于汽车内的主动降噪方法
CN104908688A (zh) * 2015-05-20 2015-09-16 浙江吉利汽车研究院有限公司 车辆主动降噪的方法及装置
CN105263088A (zh) * 2015-10-21 2016-01-20 莆田市云驰新能源汽车研究院有限公司 一种汽车降噪方法及系统
CN106382143A (zh) * 2016-12-01 2017-02-08 吉林大学 一种基于发动机转速的主动降噪装置及方法

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111723415A (zh) * 2020-06-15 2020-09-29 中科上声（苏州）电子有限公司 一种车辆降噪系统的性能评估方法及装置
CN111723415B (zh) * 2020-06-15 2024-02-27 中科上声（苏州）电子有限公司 一种车辆降噪系统的性能评估方法及装置
CN111798831A (zh) * 2020-06-16 2020-10-20 武汉理工大学 一种声音粒子合成方法及装置
CN111798831B (zh) * 2020-06-16 2023-11-28 武汉理工大学 一种声音粒子合成方法及装置
CN112185335A (zh) * 2020-09-27 2021-01-05 上海电气集团股份有限公司 一种降噪方法、装置、电子设备及存储介质
CN112185335B (zh) * 2020-09-27 2024-03-12 上海电气集团股份有限公司 一种降噪方法、装置、电子设备及存储介质

Also Published As

Publication number Publication date
CN109300465A (zh) 2019-02-01
CN109300465B (zh) 2022-05-13

Similar Documents

Publication Publication Date Title
WO2019019801A1 (zh) 新能源车及其主动降噪方法和系统
CN111081213B (zh) 新能源车及其主动声音系统和主动声音控制方法
JP6557465B2 (ja) エンジン音合成装置を含む音声システム
JP4888386B2 (ja) エンジン音加工装置
JP5184896B2 (ja) アクティブノイズ制御システム
EP3703048B1 (en) Active noise reduction method and system, and vehicle using alternative energy
WO2018184434A1 (zh) 新能源车及其主动降噪方法、系统
WO2019033832A1 (zh) 轨道车辆的噪音处理方法、装置、设备及存储介质
WO2018153243A1 (zh) 电机高频噪声的掩蔽方法和装置
Boucher et al. Sound quality metric indicators of rotorcraft noise annoyance using multilevel regression analysis
JP2014201300A (ja) 車両接近通報装置及び車両接近通報方法
CN111128208B (zh) 一种便携式激励器
WO2018161829A1 (zh) 新能源车及提高新能源车内声品质的方法、系统
Blandin et al. Influence of the vocal tract on voice directivity
Bader Characterizing classical guitars using top plate radiation patterns measured by a microphone array
JP2011079389A (ja) ビビリ音発生防止方法およびビビリ音発生防止装置
JP2014209077A (ja) びびり音評価方法
Krebber et al. Sound quality of vehicle exterior noise
Sataloff et al. The Physics of Sound. 2
Miura et al. Fluctuation strength on real sound: Motorbike exhaust and marimba tremolo
KR20240005445A (ko) 감성 케어 장치 및 방법
Hirate et al. V6-SUV engine sound development
Lee et al. Active design of a target sound to achieve the desired sound quality inside a car cabin
Rajora Noise suppression using active noise control and masking
Bristow Noise in private cars

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18838243

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18838243

Country of ref document: EP

Kind code of ref document: A1