Noise reduction method and device for air compressor of fuel cell vehicle

Abstract

The invention discloses a noise reduction method and device for an air compressor of a fuel cell vehicle in the technical field of vibration noise of hydrogen fuel commercial vehicles, and aims to solve the technical problem that the noise reduction effect of the air compressor is not ideal. The method comprises the steps that according to the frequency of air compressor noise, audio data of a secondary sound source which is the same as the air compressor noise in amplitude and frequency and opposite to the air compressor noise in phase are obtained, the audio data of the secondary sound source are output, and the audio data of the secondary sound source are used for conducting active noise reduction on the air compressor noise; through the frequency of the noise of the air compressor, the secondary sound source which is the same as the frequency in amplitude and frequency and opposite to the frequency in phase is obtained, and the efficient noise reduction effect is achieved by means of interference superposition and mutual offset between the secondary sound source and the noise of the air compressor.

Description

Technical Field

[0001] The invention relates to a method and device for reducing noise of an air compressor of a fuel cell vehicle, belonging to the technical field of vibration noise of hydrogen fuel commercial vehicles. Background Art

[0002] The noise of traditional fuel vehicles mainly comes from the engine, while the noise of fuel cell vehicles mainly comes from the air compressor. The power conversion of the fuel cell stack itself is very quiet, but maintaining the normal operation of the fuel cell stack requires a complex air supply, exhaust, and cooling guarantee system. The air compressor is the main source of noise in the guarantee system. The noise of the air compressor has a great impact on the comfort of the whole vehicle. The existing air compressor noise reduction measures are generally passive noise reduction, such as installing silencer components or strengthening the sealing effect of the cab, but the noise reduction effect of the existing noise reduction measures is not ideal. Summary of the invention

[0003] The purpose of the present application is to overcome the deficiencies in the prior art and to provide a noise reduction method and device for an air compressor of a fuel cell vehicle that can efficiently reduce the noise.

[0004] In order to achieve the above objectives, this application is implemented by adopting the following technical solutions:

[0005] In a first aspect, the present application provides a method for reducing noise of an air compressor of a fuel cell vehicle, comprising: Obtain the vibration frequency of the air compressor and the eddy current noise frequency of the air compressor in the area to be noise reduced; Respectively obtain audio data of secondary sound sources with the same amplitude, the same frequency, and the opposite phase as the air compressor vibration frequency and the air compressor eddy current noise frequency; The secondary sound source is played according to the audio data of the secondary sound source, so that the secondary sound source and the air compressor noise interfere, overlap and cancel each other out, thereby achieving active noise reduction of the air compressor noise.

[0006] In some embodiments of the first aspect, obtaining the vibration frequency of the air compressor and the eddy current noise frequency of the air compressor in the area to be noise reduced includes: Obtaining the rotation speed and resonant acceleration of the air compressor, calibrating the vibration harmonic order of the air compressor according to the resonant acceleration of the air compressor, and calculating and obtaining the vibration frequency of the air compressor according to the rotation speed and the vibration harmonic order of the air compressor; The eddy current noise of the air compressor in the area to be reduced is obtained, the eddy current noise harmonic order of the air compressor is calibrated according to the eddy current noise of the air compressor, and the eddy current noise frequency of the air compressor is calculated according to the rotation speed, number of impellers and harmonic order of the eddy current noise of the air compressor.

[0007] In some embodiments of the first aspect, the vibration frequency of the air compressor is calculated by the following formula: , In the formula, is the vibration frequency of the air compressor, is the vibration harmonic order of the air compressor, is the speed of the air compressor.

[0008] In some embodiments of the first aspect, the eddy current noise frequency of the air compressor is calculated by the following formula: , In the formula, is the frequency of eddy current noise of air compressor, is the harmonic order of eddy current noise, is the number of impellers of the air compressor, is the speed of the air compressor.

[0009] In some embodiments of the first aspect, the air compressor speed is extracted from a control strategy preset by a vehicle controller VCU. In some embodiments of the first aspect, it is characterized in that playing the secondary sound source according to the audio data of the secondary sound source includes: Collecting the environmental noise source signal sequence when playing the secondary sound source, and arranging the real-time vibration frequency of the air compressor and the eddy current noise frequency of the air compressor into a control reference signal sequence sorted by sampling time; Acquire an optimal solution of a controller coefficient according to the environmental noise source signal sequence and the control reference signal sequence, and adjust the playback control of the secondary sound source according to the optimal solution of the controller coefficient; The optimal solution of the controller coefficient is obtained by the following calculation: , In the formula, is the optimal solution of the controller coefficient, To control the reference signal sequence, To control the length of the reference signal sequence, is the first signal in the control reference signal sequence, To control the second signal in the reference signal sequence, and so on, To control the counting number of a signal in the reference signal sequence, is the environmental noise source signal sequence, is the environmental noise source signal sequence, is the first signal in the environmental noise source sequence An environmental noise source signal, is the mathematical expectation, is the inverse matrix.

[0010] In a second aspect, the present application further provides an air compressor noise reduction device for a fuel cell vehicle, the air compressor noise reduction device for a fuel cell vehicle comprising: A controller, for obtaining the air compressor vibration frequency and the air compressor eddy current noise frequency in the area to be noise reduced; and respectively obtaining audio data of a secondary sound source having the same amplitude, the same frequency and the opposite phase as the air compressor vibration frequency and the air compressor eddy current noise frequency; A speaker is electrically connected to the controller, and is used to play the secondary sound source according to the audio data of the secondary sound source, so that the secondary sound source and the air compressor noise interfere with each other and cancel each other out, thereby achieving active noise reduction of the air compressor noise.

[0011] In some embodiments of the second aspect, the air compressor noise reduction device for the fuel cell vehicle further includes an acceleration sensor for collecting the resonant acceleration of the air compressor, and a microphone for collecting the eddy current noise frequency of the air compressor in the area to be reduced; The controller is specifically used for: calibrating the vibration harmonic order of the air compressor according to the resonant acceleration of the air compressor, and calculating the vibration frequency of the air compressor according to the rotation speed and vibration harmonic order of the air compressor; calibrating the eddy current noise harmonic order of the air compressor according to the eddy current noise of the air compressor, and calculating the eddy current noise frequency of the air compressor according to the rotation speed, number of impellers and harmonic order of the eddy current noise of the air compressor.

[0012] In a third aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method for reducing noise of an air compressor of a fuel cell vehicle as described in any embodiment of the first aspect.

[0013] In a fourth aspect, the present application also provides a computer program product, including a computer program / instruction, characterized in that when the computer program / instruction is executed by a processor, the steps of the air compressor noise reduction method for a fuel cell vehicle described in any embodiment of the first aspect are implemented.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The air compressor noise reduction method and device for fuel cell vehicles provided in the present application obtain a secondary sound source with the same frequency amplitude, frequency and opposite phase as the air compressor noise through the frequency of the air compressor noise, and utilize the interference superposition between the secondary sound source and the air compressor noise to cancel each other out, thereby achieving an efficient noise reduction effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present application or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work. Figure 1 is a flowchart of the steps of the air compressor noise reduction method for a fuel cell vehicle provided in this embodiment; Figure 2 A comparison diagram of sound pressure-Hertz curves before and after noise reduction when the noise reduction method for an air compressor of a fuel cell vehicle provided by this embodiment is applied in the cab of a hydrogen fuel cell heavy truck; Figure 3 is a schematic structural diagram of an air compressor noise reduction device for a fuel cell vehicle provided in this embodiment; Figure 4 is a schematic block diagram of the principles of the computer device provided in this embodiment; In the figure: 1-controller; 2-speaker. DETAILED DESCRIPTION

[0016] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0017] The term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship. Embodiment 1:

[0018] Figure 1 This is a flow chart of a method for reducing noise of an air compressor of a fuel cell vehicle in the first embodiment of the present invention. This flow chart only shows the logical sequence of the method described in this embodiment. In other possible embodiments of the present invention, different methods may be used without conflict. Figure 1 The steps shown or described are accomplished in the order shown.

[0019] The method for reducing noise of the air compressor of a fuel cell vehicle provided in this embodiment can be applied to a terminal and can be performed by an air compressor noise reduction device of a fuel cell vehicle, which can be implemented by software and / or hardware, for example: a vehicle controller VCU. Figure 1 The method of this implementation specifically includes the following steps: Obtain the air compressor vibration frequency and air compressor eddy current noise frequency in the air compressor noise; Respectively obtain audio data of secondary sound sources with the same amplitude, the same frequency, and the opposite phase as the air compressor vibration frequency and the air compressor eddy current noise frequency; The secondary sound source is played according to the audio data of the secondary sound source, so that the secondary sound source and the air compressor noise interfere, overlap and cancel each other out, thereby achieving active noise reduction of the air compressor noise.

[0020] After research, it was found that the noise frequencies in the air compressor noise mainly include the air compressor vibration frequency and the air compressor eddy current noise frequency. The air compressor noise is mainly the vibration noise of the motor body during the rotation of the motor and the friction noise between the fan blades and the air. The air compressor noise reduction method for fuel cell vehicles provided in this embodiment will mainly focus on the active noise reduction of these two noises to improve the noise reduction efficiency.

[0021] The secondary sound source is designed based on frequency amplitude, frequency and phase. It is used to offset the "anti" noise of the noise. In the area to be reduced (such as the cab), the secondary sound source is played, and the secondary sound source and the air compressor noise undergo destructive interference in frequency.

[0022] Therefore, compared with the traditional passive noise reduction method, the air compressor noise reduction method for fuel cell vehicles provided in this embodiment processes the air compressor vibration frequency and the air compressor eddy current noise frequency, plays a secondary sound source with the same frequency, amplitude and opposite phase, and actively reduces the air compressor vibration noise and air compressor eddy current noise that play a decisive role in the air compressor noise. It can adapt to air compressor noises of different frequencies and amplitudes and achieve efficient noise reduction in the cab waiting for noise reduction area.

[0023] The acquisition of the air compressor vibration frequency and the air compressor eddy current noise frequency can be achieved in other forms known in the art, such as by measuring the harmonic order, or real-time measurement, or even more other known forms, which will not be repeated here. Embodiment 2:

[0024] This embodiment provides a method for reducing the noise of an air compressor of a fuel cell vehicle. This embodiment is optimized on the basis of the first embodiment to improve the technical effect and refine the technical solution. For details not fully described in this embodiment, please refer to the first embodiment.

[0025] As mentioned in Example 1, the main sources of air compressor noise frequency are divided into two categories. One is the mechanical vibration generated by the air compressor during operation, that is, the air compressor vibration frequency. The air compressor vibration frequency will be transmitted to the area to be reduced (such as the cab) through the physical vibration of adjacent components. The other is the air compressor eddy current noise generated by the friction and collision between the air compressor blades and the air. The air compressor eddy current noise is transmitted to the area to be reduced (such as the cab) through acoustics. These two types of noise sources have different sources and properties.

[0026] In a further but non-limiting embodiment of the present application, the vibration frequency of the air compressor is calculated by the following formula: , In the formula, is the vibration frequency of the air compressor, is the vibration harmonic order of the air compressor, is the air compressor speed.

[0027] If the air compressor model used in the vehicle has built-in speed monitoring, the air compressor speed can be obtained through the signal port of the air compressor, or a special speed measuring device can be set up to measure the air compressor speed; the vibration harmonic order of the air compressor needs to be measured and calibrated before use. Different models of air compressors, the same model of air compressors installed in different positions of the vehicle, and even the same model of air compressors installed in the same position of the vehicle but in different vehicle conditions may result in different vibration harmonic orders of the air compressor. After the installation or maintenance of the air compressor is completed, a separate vibration harmonic order calibration can be performed on each air compressor.

[0028] In a further but non-limiting embodiment of the present application, the air compressor eddy current noise frequency is obtained by an acquisition formula, and the acquisition formula of the air compressor eddy current noise frequency is as follows: , In the formula, is the frequency of eddy current noise of air compressor, is the harmonic order of eddy current noise, is the number of air compressor impellers, is the air compressor speed.

[0029] Similar to the vibration harmonic order of the air compressor, the eddy current noise harmonic order of air compressors in different states is also different. Therefore, after the installation or maintenance of the air compressor, each air compressor can be calibrated individually for the eddy current noise harmonic order.

[0030] As one embodiment, the harmonic order of eddy current noise is preferentially measured in the area to be reduced.

[0031] The phase difference consistency between the secondary sound source and the air compressor noise is also a major factor affecting the noise reduction effect. In a further but non-limiting embodiment of the present application, the air compressor speed is extracted from the control strategy preset by the vehicle controller VCU. Refer to Table 1, which is a typical control strategy. According to the control strategy, the VCU adjusts the hydrogen fuel cell system request power and air compressor speed for different charging state SOC values ​​of the power battery.

[0032] The execution error of the existing air compressor for the control strategy is small, so the air compressor speed directly extracted from the control strategy is basically consistent with the air compressor speed measured physically. It is worth noting that when the air compressor speed is obtained by physical measurement, since the corresponding sensor needs a certain amount of time to process the data, the audio data of the secondary sound source calculated according to the air compressor speed will have a phase difference with the frequency of the air compressor noise, which may affect the noise reduction quality. However, the air compressor speed directly extracted from the control strategy has a shorter time to output the audio data of the secondary sound source, and the secondary sound source can sound synchronously with the air compressor noise. From another perspective, the air compressor speed in the control strategy is processed in two aspects at the same time. On the one hand, the VCU sends the air compressor control signal to the air compressor according to the corresponding air compressor speed in the control strategy. On the other hand, the same air compressor speed is used to calculate the audio data of the secondary sound source. These two aspects occur simultaneously, so the secondary sound source and the air compressor noise are almost emitted at the same time, and the phase difference is small. Due to data synchronization, the phase difference can also be corrected manually.

[0033] By using the above method, the air compressor eddy current noise frequency and the air compressor vibration frequency can be obtained relatively easily but accurately when in use. The frequencies of the air compressor noise are mainly the air compressor eddy current noise frequency and the air compressor vibration frequency. For the frequency of the air compressor noise, a secondary sound source with the same amplitude, the same frequency and the opposite phase is obtained, so that active noise reduction with objective effect can be achieved. Compared with the air compressor noise reduction method for a fuel cell vehicle provided in the previous embodiment, the air compressor noise reduction method for a fuel cell vehicle provided in this embodiment describes in detail how to obtain the vibration harmonic order and vibration harmonic order of the air compressor through the measurement work implemented, and based on the air compressor speed collected in real time from the vehicle controller VCU, the secondary sound source and the air compressor noise are highly matched in phase to eliminate the phase difference, so that the active noise reduction of the air compressor noise can be more accurate and efficient.

[0034] refer to Figure 2The air compressor noise reduction method for a fuel cell vehicle provided in this embodiment is applied in the cab of a hydrogen fuel cell heavy truck to reduce noise. The horizontal axis is Hertz and the vertical axis is sound pressure. Comparing the Hertz-sound pressure curve of the active noise reduction switch, the average value of the "active noise reduction on" curve is 59.97dB (A-weighted), and the average value of the "active noise reduction off" curve is 63.37dB (A-weighted). It is not difficult to see that the air compressor noise reduction method for a fuel cell vehicle provided in this embodiment can reduce the noise pressure in the cab by an average of about 3.5dB (A-weighted).

[0035] It is worth noting that by directly extracting the air compressor speed from the control strategy, the audio data of the secondary sound source is obtained. This strategy does not require external measurement components and relies on the original hardware of the fuel cell vehicle for execution. For example, the air compressor noise reduction method of the fuel cell vehicle is also executed in the VCU. Considering that fuel cell vehicles are basically equipped with speakers, it is only necessary to upgrade the software of the VCU to enable it to have the ability to execute the air compressor noise reduction method of the fuel cell vehicle, and then use the vehicle's own speakers for noise reduction.

[0036] The vibration harmonic order and eddy current noise harmonic order of the air compressor only need to be measured after the air compressor is installed and debugged and before it is officially used. The measured vibration harmonic order and eddy current noise harmonic order of the air compressor can be continuously used in subsequent use. This is simple and convenient. The manufacturer of fuel cell vehicles can complete the calibration work before leaving the factory.

[0037] As one embodiment, the resonant acceleration of the air compressor is obtained in advance, and the vibration harmonic order of the air compressor is calibrated according to the resonant acceleration of the air compressor; the eddy current noise of the air compressor in the area to be reduced is obtained in advance, and the eddy current noise harmonic order of the air compressor is calibrated according to the eddy current noise of the air compressor. Converting the resonant acceleration into the vibration frequency of the air compressor and obtaining the eddy current noise harmonic order according to the eddy current noise of the air compressor can be achieved in other forms known in the art, which will not be repeated here.

[0038] As one embodiment, when using the air compressor noise reduction method for a fuel cell vehicle, the noise reduction effect can be evaluated for the first use, and the amplitude frequency and phase of the secondary sound source can be adjusted to optimize the noise reduction effect of the air compressor. The specific steps are as follows: When playing the secondary sound source, the environmental noise source signal of the area where noise reduction is being performed, or the area where the noise reduction effect is expected to be further optimized, is collected with time as the minimum unit, and the collected environmental noise source signals are arranged into an environmental noise source signal sequence according to the time sequence of the moments; at the same moment when the environmental noise source signal is collected, the vibration frequency of the air compressor and the eddy current noise frequency of the air compressor are obtained, and are also arranged into a control reference signal sequence with time as the minimum unit; The optimal solution of the controller coefficient is obtained according to the control reference signal sequence and the environmental noise source signal sequence. The controller coefficient is the physical information such as the amplitude frequency and phase of the secondary sound source. The playback control of the secondary sound source is adjusted according to the optimal solution of the controller coefficient. The optimal solution of the controller coefficient is obtained by the following calculation: , In the formula, is the optimal solution of the controller coefficient, To control the reference signal sequence, To control the length of the reference signal sequence, is the first signal in the control reference signal sequence, To control the second signal in the reference signal sequence..., To control the counting number of a signal in the reference signal sequence, is the environmental noise source signal sequence, is the length of the environmental noise source signal sequence, is the mathematical expectation, is the inverse matrix.

[0039] The principle of obtaining the optimal solution of the controller coefficient is as follows: There is an error between the secondary sound source and the ambient noise source. The smaller the error, the better the noise reduction effect. After the secondary sound source signal is superimposed with the ambient noise source signal. Signal Error The acquisition formula is as follows: , In the formula, is the controller coefficient, is the secondary sound source signal sequence.

[0040] In order to effectively reduce noise, the mathematical expectation of the square of the error signal must be minimized, and the objective function can be obtained: , In the formula, is the objective function, and the optimization goal is to minimize. To control the cross-correlation function between the reference signal sequence and the environmental noise source signal sequence, is the autocorrelation function of the control reference signal sequence.

[0041] The cross-correlation function between the control reference signal sequence and the environmental noise source signal sequence is expressed as: . The autocorrelation function of the control reference signal sequence is expressed as: . Objective Function The expression for the controller coefficient is is a quadratic function, so it has a unique minimum value for the objective function Taking the derivative of the expression and setting it equal to zero, we get: , Assumptions As a non-singular matrix, the optimal solution of the controller coefficient is obtained: . Embodiment three:

[0042] refer to Figure 3 , this embodiment provides an air compressor noise reduction device for a fuel cell vehicle, including, for obtaining the air compressor vibration frequency and the air compressor eddy current noise frequency in the air compressor noise; respectively obtaining audio data of a secondary sound source with the same amplitude, the same frequency and the opposite phase as the air compressor vibration frequency and the air compressor eddy current noise frequency;

[0043] The loudspeaker 2 is electrically connected to the controller 1. The loudspeaker 2 plays the secondary sound source according to the audio data of the secondary sound source, so that the secondary sound source and the air compressor noise interfere with each other and cancel each other out, thereby achieving active noise reduction of the air compressor noise.

[0044] As one embodiment, the controller 1 is a vehicle controller VCU, and the speaker 2 is a vehicle audio system.

[0045] As one embodiment, the vibration frequency of the air compressor is obtained by an acquisition formula, and the acquisition formula of the vibration frequency of the air compressor is as follows: , In the formula, is the vibration frequency of the air compressor, is the vibration harmonic order of the air compressor, is the air compressor speed.

[0046] The air compressor eddy current noise frequency is obtained by an acquisition formula, and the acquisition formula of the air compressor eddy current noise frequency is as follows: , In the formula, is the frequency of eddy current noise of air compressor, is the harmonic order of eddy current noise, is the number of air compressor impellers, is the air compressor speed.

[0047] The air compressor speed is extracted from the control strategy preset by the VCU.

[0048] In a further but non-limiting embodiment of the present application, the air compressor noise reduction device for a fuel cell vehicle further includes an acceleration sensor installed near the air compressor installation point, and a microphone installed in the area to be noise reduced; The acceleration sensor obtains the resonant acceleration of the air compressor, which is used to pre-calibrate the vibration harmonic order of the air compressor. The microphone obtains the eddy current noise of the air compressor propagated to the area to be reduced, and the eddy current noise of the air compressor is used to pre-calibrate the eddy current noise harmonic order.

[0049] The eddy current noise harmonic order and the vibration harmonic order of the air compressor are input into the controller 1 to obtain the audio data of the secondary sound source.

[0050] The air compressor noise reduction device for a fuel cell vehicle provided in this embodiment can execute the air compressor noise reduction method for a fuel cell vehicle provided in Embodiment 1 or 2, and has the same technical effect, which will not be described in detail here.

[0051] Fuel cell passenger cars have low heat dissipation requirements, but fuel cell heavy trucks have high power, so the air compressor has high power and high noise. As one of the embodiments, deploying the fuel cell vehicle air compressor noise reduction device provided in this embodiment on a fuel cell heavy truck can greatly alleviate the noise in the cab.

[0052] As one of the embodiments, the microphone can also be used to evaluate the noise reduction effect when the air compressor noise reduction device of a fuel cell vehicle is used for the first time. The speaker 2 emits a secondary sound source in the area to be noise reduced, and the microphone collects the ambient sound after noise reduction. The secondary sound source is optimized and the relevant parameters are adjusted according to the noise reduction quality of the collected ambient sound.

[0053] To achieve the optimization of secondary sound source according to the noise reduction quality control of the collected ambient sound, the specific steps are as follows: When playing the secondary sound source, the environmental noise source signal of the area where noise reduction is being performed, or the area where the noise reduction effect is expected to be further optimized, is collected with time as the minimum unit, and the collected environmental noise source signals are arranged into an environmental noise source signal sequence according to the time sequence of the moments; at the same moment when the environmental noise source signal is collected, the vibration frequency of the air compressor and the eddy current noise frequency of the air compressor are obtained, and are also arranged into a control reference signal sequence with time as the minimum unit; The optimal solution of the controller coefficient is obtained according to the control reference signal sequence and the environmental noise source signal sequence. The controller coefficient is the physical information such as the amplitude frequency and phase of the secondary sound source. The playback control of the secondary sound source is adjusted according to the optimal solution of the controller coefficient. The optimal solution of the controller coefficient is obtained by the following calculation: , In the formula, is the optimal solution of the controller coefficient, To control the reference signal sequence, To control the length of the reference signal sequence, is the first signal in the control reference signal sequence, To control the second signal in the reference signal sequence..., To control the counting number of a signal in the reference signal sequence, is the environmental noise source signal sequence, is the length of the environmental noise source signal sequence, is the mathematical expectation, is the inverse matrix.

[0054] The principle of obtaining the optimal solution of the controller coefficient is as follows: There is an error between the secondary sound source and the ambient noise source. The smaller the error, the better the noise reduction effect. After the secondary sound source signal is superimposed with the ambient noise source signal. Signal Error The acquisition formula is as follows: , In the formula, is the controller coefficient, is the secondary sound source signal sequence.

[0055] In order to effectively reduce noise, the mathematical expectation of the square of the error signal must be minimized, and the objective function can be obtained: , In the formula, is the objective function, and the optimization goal is to minimize. To control the cross-correlation function between the reference signal sequence and the environmental noise source signal sequence, is the autocorrelation function of the control reference signal sequence.

[0056] The cross-correlation function between the control reference signal sequence and the environmental noise source signal sequence is expressed as: .

[0057] The autocorrelation function of the control reference signal sequence is expressed as: .

[0058] Objective Function The expression for the controller coefficient is is a quadratic function, so it has a unique minimum value for the objective function Taking the derivative of the expression and setting it equal to zero, we get: , Assumptions As a non-singular matrix, the optimal solution of the controller coefficient is obtained: . Embodiment 4:

[0059] This embodiment provides a computer device, including a processor and a memory connected to the processor, wherein a computer program is stored in the memory. When the computer program is executed by the processor, the steps of the air compressor noise reduction method for a fuel cell vehicle provided in Embodiment 1 or 2 are performed.

[0060] The computer device may be a server or an electronic terminal. As one embodiment, refer to Figure 4 , the computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store data acquired and generated in the air compressor noise reduction method for a fuel cell vehicle. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the air compressor noise reduction method for a fuel cell vehicle provided in embodiment one or two is implemented.

[0061] Those skilled in the art will understand that Figure 4 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0062] The computer device provided in this embodiment has the same technical effects as those in Embodiment 1 or 2, which will not be described in detail here.

[0063] As one of the embodiments, the computer device provided in this embodiment includes a vehicle controller VCU. Embodiment five:

[0064] This embodiment provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the steps of the air compressor noise reduction method for a fuel cell vehicle provided in the first or second embodiment are implemented.

[0065] The computer-readable storage medium provided in this embodiment has the same technical effects as those in Embodiment 1 or 2, and will not be described in detail here. Embodiment six:

[0066] This embodiment provides a computer program product on which a computer program is stored, and when the program is executed by a processor, the steps of the air compressor noise reduction method for a fuel cell vehicle provided in Embodiment 1 or Embodiment 2 are implemented. The computer program product provided in this embodiment can be transmitted, distributed and downloaded in the form of a signal via the Internet.

[0067] The computer program product provided in this embodiment has the same technical effects as those in Embodiment 1 or 2, and will not be described in detail here.

[0068] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0069] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0070] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0071] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0072] In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0073] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0074] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for reducing noise of an air compressor of a fuel cell vehicle, characterized in that: include, Obtain the vibration frequency of the air compressor and the eddy current noise frequency of the air compressor in the area to be noise reduced; Respectively obtain audio data of secondary sound sources with the same amplitude, the same frequency, and the opposite phase as the air compressor vibration frequency and the air compressor eddy current noise frequency; The secondary sound source is played according to the audio data of the secondary sound source, so that the secondary sound source and the air compressor noise interfere, overlap and cancel each other out, thereby achieving active noise reduction of the air compressor noise.

2. The method for reducing noise of an air compressor of a fuel cell vehicle according to claim 1, characterized in that: The obtaining of the air compressor vibration frequency and the air compressor eddy current noise frequency in the area to be noise reduced includes: Obtaining the rotation speed and resonant acceleration of the air compressor, calibrating the vibration harmonic order of the air compressor according to the resonant acceleration of the air compressor, and calculating and obtaining the vibration frequency of the air compressor according to the rotation speed and the vibration harmonic order of the air compressor; The eddy current noise of the air compressor in the area to be reduced is obtained, the eddy current noise harmonic order of the air compressor is calibrated according to the eddy current noise of the air compressor, and the eddy current noise frequency of the air compressor is calculated according to the rotation speed, number of impellers and harmonic order of the eddy current noise of the air compressor.

3. The method for reducing noise of an air compressor of a fuel cell vehicle according to claim 2, characterized in that: The vibration frequency of the air compressor is calculated by the following formula: ， In the formula, is the vibration frequency of the air compressor, is the vibration harmonic order of the air compressor, is the speed of the air compressor.

4. The method for reducing noise of an air compressor of a fuel cell vehicle according to claim 2, characterized in that: The air compressor eddy current noise frequency is calculated by the following formula: ， In the formula, is the frequency of eddy current noise of air compressor, is the harmonic order of eddy current noise, is the number of impellers of the air compressor, is the speed of the air compressor.

5. The method for reducing noise of an air compressor of a fuel cell vehicle according to claim 3 or 4, characterized in that: The air compressor speed is extracted from the control strategy preset by the vehicle controller VCU.

6. The method for reducing noise of an air compressor of a fuel cell vehicle according to claim 2, characterized in that: said playing the secondary sound source according to the audio data of said secondary sound source, include, Collecting the environmental noise source signal sequence when playing the secondary sound source, and arranging the real-time vibration frequency of the air compressor and the eddy current noise frequency of the air compressor into a control reference signal sequence sorted by sampling time; Acquire an optimal solution of a controller coefficient according to the environmental noise source signal sequence and the control reference signal sequence, and adjust the playback control of the secondary sound source according to the optimal solution of the controller coefficient; The optimal solution of the controller coefficient is obtained by the following calculation: ， In the formula, is the optimal solution of the controller coefficient, To control the reference signal sequence, To control the length of the reference signal sequence, is the first signal in the control reference signal sequence, To control the second signal in the reference signal sequence, and so on, To control the counting number of a signal in the reference signal sequence, is the environmental noise source signal sequence, is the environmental noise source signal sequence, is the first signal in the environmental noise source sequence An environmental noise source signal, is the mathematical expectation, is the inverse matrix.

7. A noise reduction device for an air compressor of a fuel cell vehicle, characterized in that: The air compressor noise reduction device of the fuel cell vehicle comprises: A controller (1) is used to obtain the air compressor vibration frequency and the air compressor eddy current noise frequency in the area to be reduced; and to obtain audio data of a secondary sound source having the same amplitude, the same frequency and the opposite phase as the air compressor vibration frequency and the air compressor eddy current noise frequency; A loudspeaker (2) is electrically connected to the controller (1), and the loudspeaker (2) is used to play the secondary sound source according to the audio data of the secondary sound source, so that the secondary sound source and the air compressor noise interfere with each other and cancel each other out, thereby achieving active noise reduction of the air compressor noise.

8. The air compressor noise reduction device for a fuel cell vehicle according to claim 7, characterized in that: The air compressor noise reduction device for a fuel cell vehicle also includes an acceleration sensor for collecting the resonant acceleration of the air compressor, and a microphone for collecting the eddy current noise frequency of the air compressor in the area to be reduced; The controller (1) is specifically used to: calibrate the vibration harmonic order of the air compressor according to the resonant acceleration of the air compressor, and calculate the vibration frequency of the air compressor according to the rotation speed and vibration harmonic order of the air compressor; calibrate the eddy current noise harmonic order of the air compressor according to the eddy current noise of the air compressor, and calculate the eddy current noise frequency of the air compressor according to the rotation speed, number of impellers and eddy current noise harmonic order of the air compressor.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the air compressor noise reduction method for a fuel cell vehicle according to any one of claims 1 to 6 are implemented.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method for reducing noise of an air compressor of a fuel cell vehicle as described in any one of claims 1 to 6 are implemented.

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