Sound quality control system and method for multi-channel range hood

Abstract

The invention relates to a multi-channel smoke exhaust ventilator sound quality control system and method. The system comprises three noise collection microphones, two loudspeakers and a control device. The two microphones are respectively arranged at different positions of the air inlet side of the range hood; the third microphone is arranged at an air outlet of the range hood; the two loudspeakers are respectively arranged at different positions of the air inlet side of the range hood; the third loudspeaker is arranged at an air outlet of the range hood; the method comprises the steps that S1, three loudspeakers are driven to send frequency sweeping signals respectively, three microphones collect the frequency sweeping signals respectively, and a controller identifies transfer functions from the loudspeakers to the corresponding microphones; s2, the first sound quality control algorithm drives the first loudspeaker and the second loudspeaker to generate anti-noise; the second sound quality control algorithm drives the third loudspeaker to generate anti-noise. According to the system and the method, noise generated in the working process of the smoke exhaust ventilator is inhibited, the sound quality of the smoke exhaust ventilator is effectively improved, the comfort of the smoke exhaust ventilator in the using process is improved, and the user experience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of kitchen sound quality control, and in particular to a multi-channel range hood sound quality control system and method. Background Art

[0002] The range hood uses an internal exhaust device to suck in the oil smoke under the range hood and discharge it to the outside. In the process of discharging oil smoke, the extracted oil smoke enters the internal space of the range hood along with the air and rubs against the turbine fan to make noise, the exhausted air rubs against the air outlet duct and vibrates to make noise, and the noise generated by the exhaust system itself has an adverse effect on human hearing, communication during cooking, and even human emotions. At present, most of the noise reduction solutions for range hoods are implemented in a passive noise reduction way, which reduces the intensity of the range hood noise by arranging sound-absorbing and sound-absorbing materials or designing corresponding structures, but this method is not effective in controlling low-frequency noise. Some range hood noise control systems have begun to adopt active noise reduction solutions, which only control the intensity of the noise and have the problem of poor hearing comfort for the human ear.

[0003] Chinese invention patent CN117628558A discloses a multi-channel active noise control device and noise reduction method for range hoods. This patent addresses the problems of single active noise source control and poor active noise reduction robustness of existing range hoods, and proposes an active noise reduction system that uses multiple channels to simultaneously control the air outlet and air inlet of the range hood. The active noise reduction system can reduce noise at multiple locations of the range hood, and achieve noise control under different working conditions by adjusting controller parameters. However, this active noise reduction solution also has problems such as poor sound quality control and unreasonable layout of acoustic system equipment.

[0004] Chinese invention patent CN118882120A discloses a range hood control method, control device and range hood. This patent obtains the firepower curve of cooking ingredients, determines the correspondence between the sound quality function and the sound quality parameters, and improves the sound quality of the range hood noise. However, this method has shortcomings: first, the invention only adjusts the loudness of the sound quality parameters, and lacks control over sharpness and roughness in the existing range hood sound quality model; second, the active noise reduction solution of the invention requires threshold debugging during installation according to the installation scenario and range hood model, which increases the complexity of installation.

[0005] The disadvantage of the existing technology is that the active noise reduction solution has limited effect on the sound quality control of the range hood: reducing the decibel of the range hood noise will still lead to poor hearing comfort for the human ear; and the existing range hood sound quality control solution lacks adaptive control and has too few targeted sound quality parameters, resulting in unsatisfactory sound quality control effect. And it is necessary to adjust the parameters according to the installation site conditions and the installed model, which increases the difficulty of installing and debugging the range hood. Therefore, a new range hood sound quality control solution is needed to solve the above problems. Summary of the invention

[0006] The object of the present invention is to provide a multi-channel range hood sound quality control system and method, which is conducive to suppressing the noise generated during the operation of the range hood, effectively improving the sound quality of the range hood, and further improving the comfort during the use of the range hood to enhance the user experience.

[0007] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a multi-channel range hood sound quality control system, comprising a first noise collection microphone, a second noise collection microphone, a third noise collection microphone, a first speaker, a second speaker, a third speaker and a control device; the first noise collection microphone and the second noise collection microphone are respectively arranged at different positions on the air inlet side of the range hood for collecting the noise on the air inlet side; the third noise collection microphone is arranged at the air outlet of the range hood for collecting the noise at the air outlet; the first speaker and the second speaker are respectively arranged at different positions on the air inlet side of the range hood and face the first noise collection microphone and the second noise collection microphone respectively, for generating anti-noise for suppressing the noise on the air inlet side; the third speaker is arranged at the air outlet of the range hood and faces the third noise collection microphone, for generating anti-noise for suppressing the noise at the air outlet; the control device is arranged on the range hood, the control device comprises a controller and a peripheral circuit, and the first noise collection microphone, the second noise collection microphone, the third noise collection microphone, the first speaker, the second speaker, and the third speaker are respectively electrically connected to the control device.

[0008] Furthermore, the first noise collection microphone is installed on the side of the range hood smoke collection hood close to the user, and the second noise collection microphone is installed on the side of the range hood smoke collection hood away from the user, so that the comprehensive noise near the range hood air intake filter and the user is collected by the first noise collection microphone and the second noise collection microphone; the third noise collection microphone is installed on the range hood volute outlet at a set distance from the exhaust pipe, and is used to collect the comprehensive noise near the range hood air outlet and the exhaust pipe.

[0009] Furthermore, the first speaker and the second speaker are respectively installed on the left and right sides of the smoke hood of the range hood and face the first noise collection microphone and the second noise collection microphone respectively, and are used to generate counter-noise to suppress the noise on the air inlet side of the range hood; the third speaker is installed on the inner side of the range hood bellows and faces the third noise collection microphone, and is used to generate counter-noise to suppress the noise at the air outlet of the range hood.

[0010] Furthermore, the first speaker, the second speaker and the third speaker are also used to generate scanning signals under the control of the controller, the first noise collection microphone, the second noise collection microphone and the third noise collection microphone are also used to collect the swept frequency signals emitted by the corresponding speakers, and the controller is also used to identify the transfer function from the speaker to the corresponding noise collection microphone.

[0011] Furthermore, the controller is embedded with a first sound quality control algorithm and a second sound quality control algorithm, the first sound quality control algorithm is used to drive the first speaker and the second speaker to generate anti-noise, and the second sound quality control algorithm is used to drive the third speaker to generate anti-noise.

[0012] The present invention also provides a multi-channel range hood sound quality control method based on the above system, comprising the following steps:

[0013] S1, only drive the first speaker to send out a sweep frequency signal, the first noise collection microphone collects the sweep frequency signal sent out by the first speaker and transmits it to the controller, the controller identifies the first transfer function from the first speaker to the first noise collection microphone; only drive the second speaker to send out a sweep frequency signal, the second noise collection microphone collects the sweep frequency signal sent out by the second speaker and transmits it to the controller, the controller identifies the second transfer function from the second speaker to the second noise collection microphone; only drive the third speaker to send out a sweep frequency signal, the third noise collection microphone collects the sweep frequency signal sent out by the third speaker and transmits it to the controller, the controller identifies the third transfer function from the third speaker to the third noise collection microphone;

[0014] S2, the range hood and all speakers and noise collection microphones are running; the first sound quality control algorithm built into the controller selects corresponding controller parameters according to the gear operating condition of the range hood, and drives the first speaker and the second speaker to generate anti-noise according to the noise collected by the first noise collection microphone and the second noise collection microphone, so as to suppress the noise on the air inlet side of the range hood; the second sound quality control algorithm built into the controller also selects corresponding controller parameters according to the gear operating condition of the range hood, and drives the third speaker to generate anti-noise according to the noise collected by the third noise collection microphone, so as to suppress the noise at the air outlet of the range hood.

[0015] Furthermore, the identification algorithm used by the first transfer function, the second transfer function and the third transfer function is a least mean square algorithm, the controller generates a speaker driving signal as an input of the corresponding transfer function, and the signal collected by the noise collection microphone is transmitted to the controller as an output of the corresponding transfer function;

[0016] The controller parameters corresponding to different working conditions are a three-row matrix, and each row controls the first speaker, the second speaker and the third speaker respectively; before the range hood is officially put into use, the corresponding controller parameters are obtained through pre-training under different working conditions; when it is officially put into use, the pre-trained controller parameters corresponding to the current working conditions are selected as the fixed controller to generate the speaker driving signal.

[0017] Furthermore, the first sound quality control algorithm is a dual-channel FeLMS algorithm, and the algorithm adopted is an adaptive filtering error LMS algorithm;

[0018] The second sound quality control algorithm is a single-channel FeLMS algorithm, which uses an FeLMS system that adjusts and selects fixed controller parameters according to operating conditions, and the controller parameters are updated according to the operating conditions of the range hood.

[0019] Furthermore, discrete wavelet decomposition is used to analyze the sound quality characteristics of range hood noise under different gear working conditions, and the fundamental frequency band that affects the sound quality index is determined. The frequency band is set based on the sound quality index according to the results of signal analysis, thereby achieving directional sound quality control of range hood noise under different gear working conditions.

[0020] Furthermore, the frequency band setting based on the sound quality index is implemented by:

[0021] 1) Perform discrete wavelet decomposition on the range hood noise of different gear working conditions, decompose the signal into N IMF components, set each IMF component to zero in turn and perform wavelet reconstruction on all components to form a new signal Xd n ;

[0022] 2) Analyze the newly formed N noise signals Xd n The sound quality index is used to determine the IMF components that affect the overall noise signal X;

[0023] 3) After finding the IMF component that affects the overall sound quality parameter, the passband Hw of the residual filter is determined according to the frequency band interval corresponding to the IMF component.

[0024] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a multi-channel range hood sound quality control system and method, which first obtains the noise signals at the air inlet and outlet of the range hood during operation, and then generates corresponding anti-noise through a controller based on the obtained noise signals, and actively controls the sound quality of the two main noise sources at the air inlet and outlet of the range hood, thereby effectively improving the sound quality of the range hood, thereby improving the comfort of the cooking environment and improving the user experience. At the same time, the controller obtains the corresponding controller initialization parameters through pre-training under different working conditions, effectively improving the sound quality index while reducing the calculation complexity. Since there is no need to recalculate the controller parameters according to different working conditions, the tracking performance of the sound quality control system is greatly enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a structural schematic diagram of a multi-channel range hood sound quality control system according to an embodiment of the present invention;

[0026] Figure 2 is another structural schematic diagram of a multi-channel range hood sound quality control system according to an embodiment of the present invention;

[0027] Figure 3 is a circuit schematic diagram of a multi-channel range hood sound quality control system according to an embodiment of the present invention;

[0028] Figure 4 is a flow chart of the implementation of the multi-channel range hood sound quality control method according to an embodiment of the present invention;

[0029] Figure 5 is a block diagram of the implementation principle of the transfer function in an embodiment of the present invention;

[0030] Figure 6 is a control block diagram of a dual-channel FeLMS algorithm in an embodiment of the present invention;

[0031] Figure 7 is a control block diagram of a single-channel FeLMS algorithm in an embodiment of the present invention;

[0032] Figure 8 It is a flow chart for implementing frequency band setting based on sound quality index in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0034] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0035] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0036] like Figure 1-2 As shown, this embodiment provides a multi-channel range hood sound quality control system, including a first noise collection microphone 10, a second noise collection microphone 20, a third noise collection microphone 50, a first speaker 30, a second speaker 40, a third speaker 60 and a control device 70. The first noise collection microphone 10 and the second noise collection microphone 20 are respectively arranged at different positions on the air inlet side of the range hood to collect the noise on the air inlet side. The third noise collection microphone 50 is arranged at the air outlet of the range hood to collect the noise at the air outlet. The first speaker 30 and the second speaker 40 are respectively arranged at different positions on the air inlet side of the range hood and face the first noise collecting microphone 10 and the second noise collecting microphone 20 respectively, for generating counter-noise to suppress the noise on the air inlet side; the third speaker 60 is arranged at the air outlet of the range hood and faces the third noise collecting microphone 50, for generating counter-noise to suppress the noise at the air outlet; the control device 70 is arranged on the range hood, and the control device 70 includes a controller and a peripheral circuit, and the first noise collecting microphone 10, the second noise collecting microphone 20, the third noise collecting microphone 50, the first speaker 30, the second speaker 40, and the third speaker 60 are respectively electrically connected to the control device 70 through wires.

[0037] In this embodiment, the first noise collecting microphone 10 is installed on the side of the range hood hood close to the user, and the second noise collecting microphone 20 is installed on the side of the range hood hood far from the user, so that the comprehensive noise near the range hood air intake filter and the user is collected by the first noise collecting microphone 10 and the second noise collecting microphone 20. The third noise collecting microphone 50 is installed on the outlet of the range hood volute close to the exhaust pipe, and is used to collect the comprehensive noise near the range hood outlet and the exhaust pipe.

[0038] In this embodiment, the first speaker 30 and the second speaker 40 are respectively installed on the left and right sides of the smoke collecting hood of the range hood and face the first noise collecting microphone 10 and the second noise collecting microphone 20 respectively, and are used to generate anti-noise in the noise control area below the air intake filter of the range hood to suppress the noise on the air intake side of the range hood. The third speaker 60 is installed on the inner side of the range hood bellows and faces the third noise collecting microphone 50, and is used to generate anti-noise near the third noise collecting microphone 50 at the air outlet of the range hood to suppress the noise at the air outlet of the range hood.

[0039] The first speaker 30, the second speaker 40 and the third speaker 60 are also used to generate scanning signals under the control of the controller 70, the first noise collection microphone 10, the second noise collection microphone 20, the third noise collection microphone 50 are also used to collect the swept frequency signals emitted by the corresponding speakers, and the controller 70 is also used to identify the transfer function from the speaker to the corresponding noise collection microphone.

[0040] In this embodiment, the control device 70 is installed on the top of the range hood.

[0041] The controller 70 is embedded with a first sound quality control algorithm and a second sound quality control algorithm. The first sound quality control algorithm is used to drive the first speaker 30 and the second speaker 40 to generate anti-noise, and the second sound quality control algorithm is used to drive the third speaker 60 to generate anti-noise. The controller 70 collects microphone signals from three noise collection channels, runs the first sound quality control algorithm and the second sound quality control algorithm, selects controller parameters according to the working conditions of the range hood, and generates three-channel speaker driving signals.

[0042] Figure 3 is a circuit diagram of the multi-channel range hood sound quality control system in this embodiment. Figure 3As shown, the control device includes a controller and a peripheral circuit, wherein the peripheral circuit includes a power amplifier and an anti-aliasing circuit implemented based on a low-pass filter, and the controller is composed of an algorithm module, a gear judgment module, two ADC modules and two DAC modules. Among them, the first ADC module converts the noise signal collected by the first noise collection microphone 10 and the second noise collection microphone 20 from an analog signal to a digital signal, and the second ADC module converts the noise signal collected by the third noise collection microphone 50 from an analog signal to a digital signal. The algorithm module selects controller parameters according to different gears of the gear judgment module and runs the first sound quality control algorithm and the second sound quality control algorithm. The first DAC module converts the digital signal output by the algorithm module into an analog signal to drive the first speaker 30 and the second speaker 40, and the second DAC module converts the digital signal output by the algorithm module into an analog signal to drive the third speaker 60. All signal inputs and outputs are subjected to a low-pass filter to realize the anti-aliasing function, and the speaker drive signal drives the corresponding speaker to work after passing through the power amplifier module.

[0043] This embodiment also provides a multi-channel range hood sound quality control method based on the above system, comprising the following steps:

[0044] S1, only drive the first speaker to send out a sweep frequency signal, the first noise collection microphone collects the sweep frequency signal sent out by the first speaker and transmits it to the controller, the controller identifies the first transfer function from the first speaker to the first noise collection microphone; only drive the second speaker to send out a sweep frequency signal, the second noise collection microphone collects the sweep frequency signal sent out by the second speaker and transmits it to the controller, the controller identifies the second transfer function from the second speaker to the second noise collection microphone; only drive the third speaker to send out a sweep frequency signal, the third noise collection microphone collects the sweep frequency signal sent out by the third speaker and transmits it to the controller, the controller identifies the third transfer function from the third speaker to the third noise collection microphone;

[0045] S2, the range hood and all speakers and noise collection microphones are running; the first sound quality control algorithm built into the controller selects corresponding controller parameters according to the gear operating condition of the range hood, and drives the first speaker and the second speaker to generate anti-noise through the minimum mean square filtering error algorithm according to the noise collected by the first noise collection microphone and the second noise collection microphone, so as to suppress the noise on the air inlet side of the range hood; the second sound quality control algorithm built into the controller also selects corresponding controller parameters according to the gear operating condition of the range hood, and drives the third speaker to generate anti-noise through the minimum mean square filtering error algorithm according to the noise collected by the third noise collection microphone, so as to suppress the noise at the air outlet of the range hood.

[0046] Figure 44 is an implementation flow chart of the multi-channel range hood sound quality control method provided in this embodiment. The specific implementation steps of the method are as follows.

[0047] Step S110: Turn off the range hood power supply, synthesize the sweep frequency signal through the controller in the FeLMS system, and drive the first speaker 30 after passing through the power amplifier. The first microphone 10 collects the noise signal at the air inlet of the range hood and uploads it to the controller. The controller identifies the filter parameters between the first speaker and the second microphone, which are expressed as the first transfer function H 1 The transfer function H from the second microphone 20 to the second speaker 40 is 2 and the transfer function H from the third microphone 50 to the third speaker 60 3 The above methods were used for identification.

[0048] The identification algorithm used for the first transfer function, the second transfer function and the third transfer function is the least mean square algorithm. The controller generates a speaker driving signal as the input of the corresponding transfer function. The signal collected by the noise collection microphone is transmitted to the controller as the output of the corresponding transfer function. The implementation principle of the transfer function identification algorithm is as follows: Figure 5 As shown in the figure, x(n) is the sweep signal driving the speakers at each level, e(n) is the noise signal collected by the microphones at each level, d(n) is the noise signal at the microphone after transmission, and y(n) is the anti-noise signal synthesized by the system. The system continuously iterates and updates the W(z) weight coefficient. When the error signal approaches 0, the system identified by the adaptive filter is close to the true transfer function.

[0049] The controller parameters corresponding to different working conditions are a three-row matrix, and each row controls the first speaker, the second speaker and the third speaker respectively; before the range hood is officially put into use, the corresponding controller parameters are obtained through pre-training under different working conditions; when it is officially put into use, the pre-trained controller parameters corresponding to the current working conditions are selected as the fixed controller to generate the speaker driving signal.

[0050] Step S120: In this embodiment, the first sound quality control algorithm is a dual-channel FeLMS algorithm, which uses an adaptive filter error LMS algorithm; the second sound quality control algorithm is a single-channel FeLMS algorithm, which uses an FeLMS algorithm that selects fixed controller parameters according to operating conditions, and the controller parameters are updated according to the operating conditions of the range hood. The control block diagram of the dual-channel FeLMS algorithm is shown in FIG. Figure 6 The control block diagram of the single-channel FeLMS algorithm is shown in Figure 7 As shown. is the transfer function from the first speaker to the second microphone identified in step S110, is the estimate of the second function; is the transfer function from the second speaker to the second microphone identified in step S110, is the estimate of the second function; is the transfer function from the third speaker to the third microphone identified in step S110, is the estimation of the third function; x(n) is the output of the noise collected by the first microphone at time n after the transfer function; W 1 (z), W 2 (z) and W 3 (z) is the adaptive filter of the sound quality control algorithm, and the filter parameters are adjusted iteratively through the LMS algorithm; y 1 (n), y 2 (n) and y 3 (n) indicates that the “reference signal” collected by the second microphone is respectively passed through the adaptive filter W 1 (z), W 2 (z) and W 3 (z) is the driving signal after convolution; H 1 (z), H 2 (z) and H 2 (z) represents the transfer function from the real path first microphone to the second speaker, the transfer function from the real path second microphone to the second speaker and the transfer function from the real path third microphone to the third speaker; P(z) represents the transfer function from the real path noise source to the first microphone and the second microphone; and and At n moments, H 1 (z), H 2 (z) and H 3 (z) output; d 1 (n), d 2 (n) and d 3 (n) represents the output of P at time n.

[0051] The dual-channel FeLMS algorithm consists of three parts: reference signal anti-aliasing, synthesized speaker drive signal, and adaptive filter iterative update.

[0052] The signal of the estimated secondary path parameters and The input signal is converted into the transfer function identified in step S110 and the signal x collected by the controller through each microphone. n (n) Convolution is performed, and the filtering process formula is as follows:

[0053]

[0054] in, L represents the length of the filter.

[0055] The driving signals y of the first speaker, the second speaker and the third speaker 1 (n), y 2 (n) and y 3 (n) The signal x collected by each microphone 1 (n), x 2 (n) and x 3 (n) and the adaptive filter W 1 , W 2 and W 2 The linear convolution is obtained and written in matrix form as follows:

[0056]

[0057] in, L represents the length of the adaptive filter. Using the linear convolution method, the residual noise signal at the lower air outlet at time n can be expressed as:

[0058]

[0059] in,

[0060] Bandpass reference signal and The noise signal collected by each microphone is obtained through the estimated secondary path and It is convolved with the residual filter Hw set in step S230 and written in matrix form as follows:

[0061]

[0062] Bandpass error signal e f1 (n), e f2 (n) and e f3 (n) The noise signal collected by each microphone is obtained through the estimated secondary path and It is convolved with the residual filter Hw set in step S230 and written in matrix form as follows:

[0063]

[0064] The coefficients of the adaptive filter are W 1 , W 2 and W 3 The coefficients of are updated by the LMS algorithm according to the residual error signal e(n), and the update formula is:

[0065]

[0066] in,

[0067] Step S130: The first FeLMS algorithm, the second FeLMS algorithm and the range hood all work normally. The first FeLMS algorithm generates anti-noise in the vicinity of the first microphone and the second microphone at the air inlet of the range hood, and the second ANC system anti-noise generates an anti-noise signal in the vicinity of the third microphone at the air outlet of the range hood.

[0068] In this embodiment, discrete wavelet decomposition is used to analyze the sound quality characteristics of the range hood noise under different working conditions, determine the fundamental frequency band that affects the sound quality index, and perform frequency band setting based on the sound quality index according to the result of signal analysis, thereby achieving directional sound quality control of the range hood noise under different working conditions. The implementation method of the frequency band setting based on the sound quality index is:

[0069] 1) Perform discrete wavelet decomposition on the range hood noise of different gear working conditions, decompose the signal into N IMF components, set each IMF component to zero in turn and perform wavelet reconstruction on all components to form a new signal Xd n ;

[0070] 2) Analyze the newly formed N noise signals Xd n The sound quality index is used to determine the IMF components that affect the overall noise signal X;

[0071] 3) After finding the IMF component that affects the overall sound quality parameter, the passband Hw of the residual filter is determined according to the frequency band interval corresponding to the IMF component.

[0072] Figure 8 FIG. 4 is a flowchart of implementing the frequency band setting based on the sound quality index in this embodiment. Figure 8 As shown, the specific implementation steps of this method are as follows.

[0073] Step S210: Perform discrete wavelet decomposition on the range hood noise of different gear working conditions, decompose the signal into N IMF components, set one of the IMF components to zero in turn, and perform wavelet reconstruction on all components to form a new signal Xd x The wavelet decomposition results are as follows:

[0074] S=a N +d N +d N-1 +d N-2 ......+d 1 (6)

[0075] Where S is the original signal, dN ~d 1 is the detail component, a N The new signal of the approximate component remaining after wavelet decomposition is as follows:

[0076] Sd x =a N +d N-1 +d N-2 ......+d 1 -d x (7)

[0077] where d x are the components that go to zero in sequence, x = 1, 2, ..., N

[0078] Step S220: Analyze the new N noise signals Xd according to the range hood sound quality model x The sound quality index is used to determine the specific IMF components that affect the overall noise signal X. The sound quality model of the range hood is as follows:

[0079] SQ=95.026-3.828L-20.119S+30.698R (8)

[0080] Among them, SQ is the sound quality index, L is the loudness, S is the sharpness, and R is the roughness.

[0081] Step S230: after finding the IMF component affecting the sound quality parameter, determine the passband Hw of the residual filter according to the frequency band interval corresponding to the IMF component.

[0082] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A multi-channel range hood sound quality control system, characterized in that: The invention comprises a first noise collecting microphone (10), a second noise collecting microphone (20), a third noise collecting microphone (50), a first loudspeaker (30), a second loudspeaker (40), a third loudspeaker (60) and a control device (70); the first noise collecting microphone (10) and the second noise collecting microphone (20) are respectively arranged at different positions on the air inlet side of the range hood for collecting noise on the air inlet side; the third noise collecting microphone (50) is arranged at the air outlet of the range hood for collecting noise at the air outlet; the first loudspeaker (30) and the second loudspeaker (40) are respectively arranged at different positions on the air inlet side of the range hood and face the first noise collecting microphone (10) and the second noise collecting microphone (20) respectively for generating anti-noise for suppressing noise on the air inlet side; The third speaker (60) is arranged at the air outlet of the range hood and faces the third noise collecting microphone (50), and is used to generate anti-noise for suppressing the noise at the air outlet; the control device (70) is arranged on the range hood, and the control device (70) comprises a controller and a peripheral circuit; the first noise collecting microphone (10), the second noise collecting microphone (20), the third noise collecting microphone (50), the first speaker (30), the second speaker (40), and the third speaker (60) are electrically connected to the control device (70) respectively.

2. The multi-channel range hood sound quality control system according to claim 1, characterized in that: The first noise collecting microphone (10) is installed on the side of the range hood hood close to the user, and the second noise collecting microphone (20) is installed on the side of the range hood hood far from the user, so that the first noise collecting microphone (10) and the second noise collecting microphone (20) collect the comprehensive noise of the range hood air intake filter and the vicinity of the user; The third noise collecting microphone (50) is installed at a position on the outlet of the range hood volute at a set distance from the exhaust pipe, and is used to collect the comprehensive noise near the air outlet of the range hood and the exhaust pipe.

3. The multi-channel range hood sound quality control system according to claim 1, characterized in that: The first loudspeaker (30) and the second loudspeaker (40) are respectively mounted on the left and right sides of the smoke collecting hood of the range hood and are respectively facing the first noise collecting microphone (10) and the second noise collecting microphone (20), and are used to generate counter-noise to suppress the noise at the air inlet side of the range hood; the third loudspeaker (60) is mounted on the inner side of the range hood bellows and is facing the third noise collecting microphone (50), and is used to generate counter-noise to suppress the noise at the air outlet of the range hood.

4. The multi-channel range hood sound quality control system according to claim 1, characterized in that: The first speaker (30), the second speaker (40) and the third speaker (60) are also used to generate a scanning signal under the control of a controller; the first noise collection microphone (10), the second noise collection microphone (20) and the third noise collection microphone (50) are also used to collect the sweep frequency signals emitted by the corresponding speakers; and the controller is also used to identify the transfer function from the speaker to the corresponding noise collection microphone.

5. The multi-channel range hood sound quality control system according to claim 1, characterized in that: The controller is embedded with a first sound quality control algorithm and a second sound quality control algorithm, wherein the first sound quality control algorithm is used to drive a first speaker (30) and a second speaker (40) to generate anti-noise, and the second sound quality control algorithm is used to drive a third speaker (60) to generate anti-noise.

6. A multi-channel range hood sound quality control method based on the system according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1, only drive the first speaker to send out a sweep frequency signal, the first noise collection microphone collects the sweep frequency signal sent out by the first speaker and transmits it to the controller, the controller identifies the first transfer function from the first speaker to the first noise collection microphone; only drive the second speaker to send out a sweep frequency signal, the second noise collection microphone collects the sweep frequency signal sent out by the second speaker and transmits it to the controller, the controller identifies the second transfer function from the second speaker to the second noise collection microphone; only drive the third speaker to send out a sweep frequency signal, the third noise collection microphone collects the sweep frequency signal sent out by the third speaker and transmits it to the controller, the controller identifies the third transfer function from the third speaker to the third noise collection microphone; S2, the range hood and all speakers and noise collection microphones are running; the first sound quality control algorithm built into the controller selects corresponding controller parameters according to the working condition of the range hood gear, and drives the first speaker and the second speaker to generate anti-noise according to the noise collected by the first noise collection microphone and the second noise collection microphone to suppress the noise on the air inlet side of the range hood; The second sound quality control algorithm built into the controller also selects corresponding controller parameters according to the gear operating conditions of the range hood, and drives the third speaker to generate anti-noise based on the noise collected by the third noise collection microphone to suppress the noise at the air outlet of the range hood.

7. The multi-channel range hood sound quality control method according to claim 6, characterized in that: The identification algorithm used by the first transfer function, the second transfer function and the third transfer function is the least mean square algorithm, the controller generates a speaker driving signal as an input of the corresponding transfer function, and the signal collected by the noise collection microphone is transmitted to the controller as an output of the corresponding transfer function; The controller parameters corresponding to different working conditions are a three-row matrix, and each row controls the first speaker, the second speaker and the third speaker respectively; before the range hood is officially put into use, the corresponding controller parameters are obtained through pre-training under different working conditions; when it is officially put into use, the pre-trained controller parameters corresponding to the current working conditions are selected as the fixed controller to generate the speaker driving signal.

8. The multi-channel range hood sound quality control method according to claim 7, characterized in that: The first sound quality control algorithm is a dual-channel FeLMS algorithm, which uses an adaptive filtering error LMS algorithm; The second sound quality control algorithm is a single-channel FeLMS algorithm, which uses an FeLMS system that adjusts and selects fixed controller parameters according to operating conditions, and the controller parameters are updated according to the operating conditions of the range hood.

9. The multi-channel range hood sound quality control method according to claim 1, characterized in that: Discrete wavelet decomposition is used to analyze the sound quality characteristics of range hood noise under different working conditions, and the fundamental frequency band that affects the sound quality index is determined. According to the results of signal analysis, the frequency band is set based on the sound quality index, thereby realizing directional sound quality control of range hood noise under different working conditions.

10. The multi-channel range hood sound quality control method according to claim 9, characterized in that: The frequency band setting based on the sound quality index is implemented as follows: 1) Perform discrete wavelet decomposition on the range hood noise of different gear working conditions, decompose the signal into N IMF components, set each IMF component to zero in turn and perform wavelet reconstruction on all components to form a new signal Xd n ; 2) Analyze the newly formed N noise signals Xd n The sound quality index is used to determine the IMF components that affect the overall noise signal X; 3) After finding the IMF component that affects the overall sound quality parameter, the passband Hw of the residual filter is determined according to the frequency band interval corresponding to the IMF component.

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