A noise reduction method and device of an air conditioner, the air conditioner, and a storage medium

Abstract

The application discloses a noise reduction method and device of an air conditioner, the air conditioner, a storage medium and a computer program product, and relates to the technical field of air conditioners. The method comprises the following steps: collecting sound wave signals at least at two positions in an air duct of the air conditioner; identifying the types of abnormal sounds in the air duct of the air conditioner according to the sound wave signals, wherein the types of abnormal sounds include fan bearing abnormal sound and thermal stress abnormal sound; generating reverse sound waves suitable for the types of abnormal sounds based on air conditioner operation parameters and environmental parameters; outputting the reverse sound waves to the air duct of the air conditioner; and iteratively adjusting the parameters of the reverse sound waves according to the feedback sound wave signals after the reverse sound waves are output, until the noise meets preset conditions. The scheme improves the accuracy and adaptability of noise reduction of the air conditioner, and improves the noise reduction effect and stability under complex working conditions.

Description

Technical Field

[0001] This invention belongs to the field of air conditioning technology, specifically relating to a noise reduction method, device, air conditioner, storage medium, and computer program product for an air conditioner. Background Technology

[0002] As air conditioning products rapidly evolve towards higher comfort and lower noise levels, the combined effect of thermal stress noise caused by the expansion and contraction of the casing and mechanical noise generated by the fan bearings has become a core bottleneck restricting the improvement of air conditioning noise reduction performance. Most noise reduction solutions for air conditioners employ passive noise reduction methods, such as thickening sound-absorbing cotton, optimizing the duct structure, and adding vibration-damping supports. However, these solutions have inherent drawbacks: firstly, they increase duct resistance and reduce airflow and heat exchange efficiency; secondly, they only weaken noise propagation and cannot suppress noise at its source, especially for non-periodic, sudden high-frequency pulse noise caused by thermal stress. Furthermore, they are easily affected by changes in ambient temperature and humidity, resulting in insufficient noise reduction stability and significant residual noise during air conditioner operation, severely degrading the user experience.

[0003] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The purpose of this invention is to provide a noise reduction method, device, air conditioner, storage medium, and computer program product for air conditioners, so as to solve the problem of poor noise reduction effect of air conditioners in related solutions, thereby improving the accuracy and adaptability of air conditioner noise reduction, and improving the noise reduction effect and stability under complex working conditions.

[0005] This invention provides a noise reduction method for an air conditioner, comprising: acquiring sound wave signals from at least two locations within the air conditioner duct; identifying the type of abnormal noise within the air conditioner duct based on the sound wave signals, wherein the abnormal noise type includes fan bearing abnormal noise and thermal stress abnormal noise; generating an anti-phase sound wave adapted to the type of abnormal noise based on air conditioner operating parameters and environmental parameters; outputting the anti-phase sound wave into the air conditioner duct; and iteratively adjusting the parameters of the anti-phase sound wave based on the sound wave signal fed back after outputting the anti-phase sound wave until the noise meets preset conditions.

[0006] In some embodiments, the acoustic signals include acoustic signals on both sides of the fan bearing, as well as acoustic signals upstream of the fan and downstream of the fan along the airflow direction within the duct.

[0007] In some embodiments, identifying the type of abnormal noise in the air conditioning duct based on the sound wave signal includes: when there is a peak value centered on the motor speed frequency in the spectrum of the sound wave signal, it is determined to be abnormal noise of the fan bearing; when the sound wave signal is a broadband random pulse signal, it is determined to be abnormal noise of thermal stress.

[0008] In some implementations, the parameters of the anti-phase sound wave include frequency, amplitude, and phase; generating an anti-phase sound wave adapted to the type of abnormal noise based on air conditioning operating parameters and environmental parameters includes: coupling the air conditioning operating parameters with the environmental parameters to calculate, determining the parameters of the anti-phase sound wave, and generating an anti-phase sound wave of the corresponding frequency band.

[0009] In some embodiments, outputting the anti-phase sound wave into the air conditioning duct includes: continuously outputting the anti-phase sound wave for abnormal noise from the fan bearing; and intermittently outputting the anti-phase sound wave for abnormal noise from thermal stress.

[0010] In some embodiments, the step of iteratively adjusting the parameters of the antiphase sound wave based on the sound wave signal fed back after the output of the antiphase sound wave includes: successively correcting the parameters of the antiphase sound wave based on the deviation between the feedback sound wave signal and preset conditions until the noise meets the preset conditions; the preset conditions are that the noise level of the feedback sound wave signal is lower than a preset threshold or the noise fluctuation is within a preset range.

[0011] In conjunction with the above method, another aspect of the present invention provides a noise reduction device for an air conditioner, comprising: a acquisition unit configured to acquire sound wave signals from at least two locations within the air conditioning duct; a processing unit configured to identify the type of abnormal noise within the air conditioning duct based on the sound wave signals, the abnormal noise type including fan bearing abnormal noise and thermal stress abnormal noise; the processing unit is further configured to generate an anti-phase sound wave adapted to the type of abnormal noise based on air conditioning operating parameters and environmental parameters; an output unit configured to output the anti-phase sound wave into the air conditioning duct; the output unit is further configured to iteratively adjust the parameters of the anti-phase sound wave based on the sound wave signal fed back after outputting the anti-phase sound wave, until the noise meets preset conditions.

[0012] In some embodiments, the acoustic signals include acoustic signals on both sides of the fan bearing, as well as acoustic signals upstream of the fan and downstream of the fan along the airflow direction within the duct.

[0013] In some implementations, the processing unit, in identifying the type of abnormal noise in the air conditioning duct based on the acoustic signal, includes: when there is a peak value centered on the motor speed frequency in the spectrum of the acoustic signal, it is determined to be abnormal noise of the fan bearing; when the acoustic signal is a broadband random pulse signal, it is determined to be abnormal noise of thermal stress.

[0014] In some embodiments, the parameters of the anti-phase sound wave include frequency, amplitude, and phase; the processing unit, in generating an anti-phase sound wave adapted to the type of abnormal noise based on air conditioning operating parameters and environmental parameters, includes: coupling the air conditioning operating parameters and the environmental parameters to calculate, determining the parameters of the anti-phase sound wave, and generating an anti-phase sound wave of the corresponding frequency band.

[0015] In some embodiments, the output unit, which outputs the anti-phase sound wave into the air conditioning duct, includes: continuously outputting the anti-phase sound wave for abnormal noise from the fan bearing; and intermittently outputting the anti-phase sound wave for abnormal noise from thermal stress.

[0016] In some implementations, the output unit, in the step of iteratively adjusting the parameters of the anti-phase sound wave based on the sound wave signal fed back after the output of the anti-phase sound wave, includes: successively correcting the parameters of the anti-phase sound wave based on the deviation between the feedback sound wave signal and preset conditions, until the noise meets the preset conditions; the preset conditions are that the noise level of the feedback sound wave signal is lower than a preset threshold, or the noise fluctuation is within a preset range.

[0017] In conjunction with the above-described device, the present invention further provides an air conditioner, comprising: the noise reduction device of the air conditioner described above.

[0018] In conjunction with the above method, the present invention further provides a storage medium comprising a stored program, wherein, when the program is executed, the device on which the storage medium is located executes the noise reduction method of the air conditioner described above.

[0019] In conjunction with the above method, the present invention further provides a computer program product comprising a computer program that, when processed and executed, implements the steps of the noise reduction method for the air conditioner described above.

[0020] The present invention first collects acoustic signals from at least two locations within the air conditioning duct. Then, based on the acoustic signals, it identifies two types of abnormal noise: fan bearing noise and thermal stress noise. Next, it combines air conditioning operating parameters and environmental parameters to generate an inverse acoustic wave adapted to the specific type of noise and outputs it into the duct. Finally, it iteratively adjusts the parameters of the inverse acoustic wave based on the feedback acoustic signals until the noise meets preset conditions. This enables precise noise reduction for different types of abnormal noise, effectively improving the adaptability of the noise reduction solution and the stability of the noise reduction effect.

[0021] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention.

[0022] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0023] Figure 1 This is a schematic flowchart of an embodiment of the noise reduction method for air conditioning according to the present invention; Figure 2 This is a schematic diagram of the structure of an embodiment of the noise reduction device for an air conditioner according to the present invention; Figure 3 This is a schematic diagram of an air conditioner structure; Figure 4 This is a flowchart illustrating an air conditioning noise reduction control method.

[0024] Referring to the accompanying drawings, the reference numerals in the embodiments of the present invention are as follows: 1-Air conditioner housing; 2-Air duct; 3-Fan bearing; 4-Upper end acoustic collector of air duct; 5-Lower end acoustic collector of air duct; 6-Acoustic collectors on both sides of the upper bearing of the fan; 7-Acoustic collectors on both sides of the lower bearing of the fan; 101-Acquisition unit; 102-Processing unit; 103-Output unit. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0026] According to embodiments of the present invention, a noise reduction method for an air conditioner is provided, such as... Figure 1 The flowchart of an embodiment of the method of the present invention is shown. The noise reduction method of the air conditioner may include steps S110 to S150.

[0027] In step S110, acoustic signals are collected from at least two locations within the air conditioning duct.

[0028] Acoustic signals collected from a single location are easily affected by local airflow and structural obstructions. Simultaneous acquisition from multiple points can comprehensively and accurately obtain the overall noise situation within the duct, avoiding subsequent misjudgments caused by local signal deviations. Acoustic signals can intuitively reflect the magnitude, frequency, and variation patterns of noise inside the duct.

[0029] In some embodiments, the acoustic signals include acoustic signals on both sides of the fan bearing, as well as acoustic signals upstream of the fan and downstream of the fan along the airflow direction within the duct.

[0030] The air conditioner's fan is located within the duct, and the fan bearing is the direct source of abnormal noise. Setting up sampling points on both sides of the bearing allows for close-range capture of the raw noise signals generated by the bearing's operation, preserving the frequency, amplitude, and other characteristics of the noise to the greatest extent possible, and avoiding signal attenuation and distortion during propagation. Airflow carries noise through the duct, and different intensities and propagation states of noise are distributed in the upstream and downstream areas of the fan. Adding sampling points at these two locations allows for the collection of the signal state of the noise after propagation along the airflow. Combining signals from multiple points provides a comprehensive understanding of the noise distribution throughout the entire duct space, preventing issues such as incomplete signal coverage or missing characteristics due to the limited location of a single sampling point.

[0031] Figure 3 The diagram shows the air conditioner structure. The fan bearing 3 is located inside the air duct 2 and is the main source of abnormal noise from the fan bearing. The upper end sound wave collector 4 is located at the top of the air duct 2, and the lower end sound wave collector 5 is located at the bottom of the air duct 2. Both of them collect the sound wave signals propagating along the airflow direction within the air duct 2. The upper bearing sound wave collectors 6 are paired on both sides of the upper end of the fan bearing 3, and the lower bearing sound wave collectors 7 are paired on both sides of the lower end of the fan bearing 3. Both of them are close to the noise source and capture the original sound wave signals generated by the operation of the fan bearing 3 at close range.

[0032] Optionally, multiple points at different distances can be selected in the upstream or downstream area of ​​the wind turbine for signal acquisition to distinguish the characteristics of near-field noise and far-field noise, thus enriching the dimensions of the signal data.

[0033] Optionally, some sound wave collectors can be configured to switch operating states, where only the points on both sides of the bearing are activated when the air conditioner is running at low load, and all points work simultaneously when the air conditioner is running at high load, thereby reducing the overall power consumption of the equipment.

[0034] In step S120, the abnormal noise type in the air conditioning duct is identified based on the sound wave signal. The abnormal noise type includes fan bearing abnormal noise and thermal stress abnormal noise.

[0035] Abnormal noise from wind turbine bearings is a mechanical noise generated during wind turbine operation due to bearing wear, abnormal clearance, or other issues. It is a periodic, continuous noise with a distinct discrete spectrum, containing one or more fixed fundamental frequencies and their higher harmonics, exhibiting regular fluctuations. Abnormal noise from thermal stress is caused by thermal expansion and contraction during operation, resulting in the compression and deformation of components. It is often sudden, with a wideband energy burst distributed in the 1kHz-8kHz range or even higher. It has poor spectral flatness, lacks a clear fundamental frequency and harmonic structure, and repeats irregularly.

[0036] The acoustic characteristics of fan bearing noise and thermal stress noise differ significantly. The generation mechanisms of these two types of noise are different, and the corresponding noise reduction methods also differ. Early identification of the noise type is a prerequisite for accurate noise reduction. Specifically, the equipment analyzes the collected acoustic signals, distinguishes the noise source by combining signal characteristics, and determines whether the current noise is fan bearing noise or thermal stress noise. Optionally, historical air conditioning operating data can be used to assist in identifying the noise type, comparing the current signal with historical noise data to improve identification accuracy.

[0037] In some implementations, step S120, identifying the type of abnormal noise in the air conditioning duct based on the acoustic signal, includes: when there is a peak value centered on the motor speed frequency in the spectrum of the acoustic signal, it is determined to be abnormal noise of the fan bearing; when the acoustic signal is a broadband random pulse signal, it is determined to be abnormal noise of thermal stress.

[0038] Fan bearing noise is mechanical noise generated by the periodic friction and collision between the bearing and the shaft during fan operation. The vibration frequency of this type of noise is directly related to the motor's rotational frequency, therefore it exhibits a concentrated peak value centered on the motor's rotational speed in the frequency spectrum, and possesses stable periodic characteristics. Thermal stress noise is noise generated by the expansion and contraction of duct components due to temperature changes, resulting in compression and friction between components. This type of noise has no fixed periodicity; its timing and intensity are random, therefore its sound wave signal appears as a broadband random pulse with a wide frequency distribution and unconcentrated energy. The spectral characteristics of these two types of noise differ significantly, allowing for rapid and accurate differentiation of noise types.

[0039] Specifically, the equipment performs spectral analysis on the acquired acoustic signals to determine the frequency distribution characteristics of the signals. When there is a significant peak in the spectrum of the acoustic signal centered on the motor speed frequency, the abnormal noise corresponding to the signal is identified as abnormal noise from the fan bearing; when the acoustic signal presents a broadband random pulse pattern without a fixed frequency center, the abnormal noise corresponding to the signal is identified as abnormal noise from thermal stress.

[0040] Optionally, based on spectrum analysis, the strength of the signal's periodicity can be used to further assist in determining the type of abnormal noise. Signals with strong periodicity are preferentially identified as abnormal noise from the fan bearing, while signals without periodicity are preferentially identified as abnormal noise from thermal stress.

[0041] Optionally, multi-dimensional recognition rules can be set, and the duration and amplitude change patterns of the signal can be combined to assist in the judgment, thereby improving the accuracy of abnormal noise recognition under complex working conditions.

[0042] In step S130, an anti-phase sound wave adapted to the type of abnormal noise is generated based on the air conditioning operating parameters and environmental parameters.

[0043] The operating status of the air conditioner and the ambient temperature and humidity directly alter the frequency, intensity, and other characteristics of abnormal noises. Combining these two types of parameters ensures that the generated anti-phase sound wave closely matches the original abnormal noise. Different types of abnormal noises correspond to anti-phase sound waves with different characteristics, thus improving the effectiveness of noise cancellation. Specifically, the equipment retrieves the current air conditioner operating parameters and environmental parameters, combines them with the identified abnormal noise type, and calculates and generates an anti-phase sound wave whose various indicators match the current abnormal noise. An anti-phase sound wave is a sound wave whose phase is completely opposite to the original noise sound wave and whose frequency matches the original noise sound wave. When this sound wave meets the original noise sound wave, they cancel each other out, thereby reducing the overall noise.

[0044] In some implementations, the parameters of the anti-phase sound wave include frequency, amplitude, and phase; in step S130, generating an anti-phase sound wave adapted to the type of abnormal noise based on air conditioning operating parameters and environmental parameters includes: coupling the air conditioning operating parameters with the environmental parameters to calculate, determining the parameters of the anti-phase sound wave, and generating an anti-phase sound wave of the corresponding frequency band.

[0045] Specifically, the system retrieves current air conditioning operating parameters and environmental parameters, couples these two types of data for calculation, and determines the frequency, amplitude, and phase of the anti-phase sound wave based on the calculation results. Ultimately, it generates an anti-phase sound wave in the corresponding frequency band that matches the current abnormal noise type. Air conditioning operating parameters include the number of fan blades, indoor fan speed, fan blade length, and set air conditioning temperature. Environmental parameters include the current indoor ambient temperature and humidity. Air conditioning operating parameters directly affect the frequency and intensity of the abnormal noise, while environmental parameters affect the vibration characteristics of the duct components and the sound wave propagation state. Coupled calculation of these two types of parameters comprehensively considers the dynamic changes in equipment operation and the environment, ensuring that the generated anti-phase sound wave highly matches the current abnormal noise characteristics, thus improving the effectiveness and stability of noise reduction.

[0046] In some embodiments, the system dynamically calculates the anti-phase sound wave based on the initially received abnormal noise waveform, combined with multi-dimensional physical parameters such as fan blade parameters and ambient temperature and humidity, in an algorithm model, rather than relying on a fixed frequency. The system reads air conditioning data, including the number of fan blades N, indoor fan speed w, fan blade length l, current indoor ambient temperature Tin, indoor ambient humidity RH, and air conditioning set operating temperature Top. It then outputs the anti-phase sound wave. Y = Asin(2Πf*t+θ) ,in f The fundamental frequency of the noise (determined by the number of blades N and the internal fan speed w, f=nw); A The amplitude value (related to the blade length l and aerophysical properties); t For the sound propagation time; θ This is the waveform compensation value (used to compensate for the propagation delay during the sound wave collector's reception of sound). θ=2Πfd / v ,in d To propagate straight-line distance, vThe speed of sound (which mainly depends on the ambient temperature Tin, and is corrected according to the ideal gas law to be v≈331.4+0.6×Tin).

[0047] In step S140, the anti-phase acoustic wave is output into the air conditioning duct.

[0048] The abnormal noise mainly propagates within the air conditioning duct. By directly outputting anti-phase sound waves into the duct, sound wave cancellation can be achieved in the main space where noise propagates, maximizing the noise reduction effect. Specifically, the sound-generating device delivers the generated anti-phase sound waves into the air conditioning duct, allowing the anti-phase sound waves to superimpose with the original abnormal noise sound waves within the duct space.

[0049] In some embodiments, step S140, outputting the anti-phase sound wave into the air conditioning duct, includes: continuously outputting the anti-phase sound wave for abnormal noise from the fan bearing; and intermittently outputting the anti-phase sound wave for abnormal noise from thermal stress.

[0050] Abnormal noise from the fan bearings is generated by the operation of the fan. This type of noise persists as long as the fan is running, and its frequency and intensity remain relatively stable. Therefore, continuous output ensures that the anti-phase sound wave always acts synchronously with the original noise, guaranteeing the continuity of the noise reduction effect and preventing recurring noise. Thermal stress noise is a sudden, intermittent noise generated by the deformation of duct components due to temperature changes. This type of noise is not continuous. Continuously outputting anti-phase sound waves would not only waste unnecessary energy but may also introduce additional sound interference when the noise disappears. Therefore, intermittent output allows for timely output of anti-phase sound waves to cancel out the noise when it appears, and pauses output when the noise disappears, ensuring noise reduction while reducing equipment power consumption and potential interference. Continuous output refers to the anti-phase sound wave generator emitting anti-phase sound waves into the duct with fixed parameters and without interruption. Intermittent output refers to the anti-phase sound wave generator emitting anti-phase sound waves discontinuously, outputting sound waves during specific periods and pausing output during other periods, resulting in an intermittent output process.

[0051] In step S150, the parameters of the anti-phase sound wave are iteratively adjusted according to the sound wave signal fed back after the output of the anti-phase sound wave until the noise meets the preset conditions.

[0052] Air conditioner operation and environmental conditions change dynamically, altering the characteristics of abnormal noises. Fixed-parameter anti-phase sound waves cannot maintain ideal noise reduction for extended periods. By using feedback signals to form a closed-loop adjustment, noise changes can be dynamically adapted to ensure continuous noise reduction. Specifically, after the anti-phase sound wave is output, the detection equipment again collects the sound wave signal within the air duct as a feedback signal. The equipment compares the feedback signal with preset conditions, continuously correcting the parameters of the anti-phase sound wave, and repeatedly performing adjustments until the noise within the air duct meets the preset standard.

[0053] In some implementations, step S150, iteratively adjusting the parameters of the anti-phase sound wave based on the sound wave signal fed back after the output of the anti-phase sound wave, includes: successively correcting the parameters of the anti-phase sound wave based on the deviation between the feedback sound wave signal and preset conditions, until the noise meets the preset conditions; the preset conditions are that the noise level of the feedback sound wave signal is lower than a preset threshold, or the noise fluctuation is within a preset range.

[0054] Air conditioning operating conditions, indoor and outdoor ambient temperatures, and fan operation status all change in real time. This causes the frequency, intensity, and other characteristics of abnormal noises within the air duct to change synchronously. Fixed, unchanging anti-phase sound wave parameters cannot maintain an ideal noise reduction effect in the long term. By relying on feedback sound wave signals, the actual noise reduction situation can be monitored in real time. By gradually adjusting parameters, the gap between the actual noise and the standard requirements can be reduced step by step, avoiding abnormal sound wave superposition caused by a one-time large adjustment of parameters.

[0055] Specifically, the equipment continuously collects noise-reduced sound wave signals from within the air duct as feedback signals. It compares various indicators of the feedback signal with preset conditions and calculates the deviation. Based on the obtained deviation results, it successively corrects parameters such as the frequency, amplitude, and phase of the anti-phase sound wave, repeating this process. The parameter adjustment stops when the noise level of the feedback sound wave signal is below a preset threshold, or when noise fluctuations remain within a preset range. Noise level is a comprehensive indicator that measures the intensity, amplitude, and energy of noise generated by sound waves, comprehensively characterizing the overall noise state within the air conditioning duct, including sound pressure level and vibration amplitude. Noise fluctuations refer to the ups and downs in the noise level of the sound wave signal during continuous acquisition, reflecting the stability of the noise state.

[0056] In some embodiments, the location for the first acquisition of acoustic signals is different from the location for acquisition of acoustic signals during subsequent iterative adjustments; the initial acquisition location includes the upper end of the air duct, the left side of the upper bearing, and the left side of the lower bearing, while the subsequent acquisition locations include the lower end of the air duct, the right side of the upper bearing, and the right side of the lower bearing.

[0057] Abnormal noises generated by the fan bearings propagate simultaneously to both sides of the bearing and the upper and lower areas of the duct. The phase, amplitude, and propagation loss of the noise received at different locations show significant differences. Initially, signals are collected at the upper end of the duct and the left side of the bearing. This prioritizes capturing the original signal along the initial noise propagation path, ensuring the basic accuracy of initial abnormal noise identification and anti-phase sound wave generation. In subsequent parameter iteration and adjustment phases, signals are collected at the lower end of the duct and the right side of the bearing. This allows for the detection of the noise's propagation through the duct space and its actual state after being superimposed and canceled by anti-phase sound waves, providing another dimension for evaluating the overall noise reduction effect. The signals from these two different areas complement each other, avoiding the problem of single signal data and distorted detection results caused by long-term use of the same set of sampling points due to factors such as local sound wave reflection, airflow interference, and equipment aging. This provides a more comprehensive basis for parameter iteration and adjustment.

[0058] Specifically, during the initial startup of the air conditioning noise reduction process, the signal acquisition equipment collects sound wave signals at three locations: the upper end of the air duct, the left side of the upper bearing, and the left side of the lower bearing. These signals are used to identify the type of abnormal noise, generate and initially output anti-phase sound waves. Once the anti-phase sound wave parameter iterative adjustment phase begins, the system automatically switches the acquisition points, ceasing signal acquisition at the original locations and instead acquiring sound wave signals at the lower end of the air duct, the right side of the upper bearing, and the right side of the lower bearing. This newly acquired set of signals is then used as feedback data to continuously correct the parameters.

[0059] Optionally, during multiple iterative adjustments, two sets of acquisition positions can be used alternately at a fixed period to further improve the comprehensiveness of signal acquisition.

[0060] Figure 4 This is a flowchart of an air conditioning noise reduction control method, which specifically includes steps 1 to 4.

[0061] Step 1: The system first detects the sound wave H1 formed by the superposition of the sound waves output from the upper end of the air duct, the left end of the upper bearing, and the left end of the lower bearing. The system quickly identifies the waveform. If the sound wave is found to be a peak value centered on the motor speed frequency, it is determined to be bearing noise. If the sound wave is found to be a broadband random pulse, it is determined to be thermal stress noise.

[0062] Step 2: Based on the initially received abnormal noise waveform, the system incorporates multi-dimensional physical parameters such as fan blade parameters and ambient temperature and humidity into the algorithm model to dynamically calculate the initial corrected sound wave, rather than relying on a fixed frequency, and outputs a canceling sound wave. Y1= Asin(2πft+θ) The sound wave is generated by the sound wave generator at the top of the air duct and lasts for 1 minute.

[0063] Step 3: After the initial output of the sound wave generator, the system detects and judges the sound wave H2 formed by the superposition of the sound waves received at the lower end of the air duct, the upper bearing right end, and the lower bearing right end. If H2 still has a peak value centered on the motor speed frequency or is a broadband random pulse, the sound wave needs to be corrected by outputting a secondary cancellation sound wave Y2 according to the calculation method of the initial cancellation sound wave Y1. The secondary cancellation sound wave Y2 is output by the sound wave generator at the lower end of the air duct for 1 minute.

[0064] Step 4: After the secondary sound wave generator finishes outputting, the system detects and judges the sound wave H3 formed by the superposition of the sound waves received at the lower / upper end of the duct, the left / right end of the upper bearing, and the left / right end of the lower bearing. If H3 meets the requirements, this control mode can be exited; if it does not meet the requirements, the optimal corrected sound wave is dynamically calculated by incorporating the fan blade parameters and multi-dimensional physical parameters such as ambient temperature and humidity into the algorithm model. The above correction process is repeated until the waveform after receiving the correction meets the requirements.

[0065] The technical solution in this embodiment collects multiple acoustic signals within the air duct, identifies the type of abnormal noise, generates and outputs a suitable inverse acoustic wave, and then dynamically adjusts the acoustic parameters based on the feedback signal to achieve closed-loop noise reduction. This effectively solves the problem of poor adaptability of traditional noise reduction methods and significantly improves the accuracy and long-term stability of noise reduction for different abnormal noises.

[0066] According to an embodiment of the present invention, a noise reduction device for an air conditioner corresponding to a noise reduction method for an air conditioner is also provided. See also Figure 2 The diagram shows a structural schematic of an embodiment of the device of the present invention. The noise reduction device of the air conditioner may include: a data acquisition unit 101, a processing unit 102, and an output unit 103.

[0067] Acquisition unit 101 is configured to acquire acoustic signals from at least two locations within the air conditioning duct.

[0068] Acoustic signals collected from a single location are easily affected by local airflow and structural obstructions. Simultaneous acquisition from multiple points can comprehensively and accurately obtain the overall noise situation within the duct, avoiding subsequent misjudgments caused by local signal deviations. Acoustic signals can intuitively reflect the magnitude, frequency, and variation patterns of noise inside the duct.

[0069] In some embodiments, the acoustic signals include acoustic signals on both sides of the fan bearing, as well as acoustic signals upstream of the fan and downstream of the fan along the airflow direction within the duct.

[0070] The air conditioner's fan is located within the duct, and the fan bearing is the direct source of abnormal noise. Setting up sampling points on both sides of the bearing allows for close-range capture of the raw noise signals generated by the bearing's operation, preserving the frequency, amplitude, and other characteristics of the noise to the greatest extent possible, and avoiding signal attenuation and distortion during propagation. Airflow carries noise through the duct, and different intensities and propagation states of noise are distributed in the upstream and downstream areas of the fan. Adding sampling points at these two locations allows for the collection of the signal state of the noise after propagation along the airflow. Combining signals from multiple points provides a comprehensive understanding of the noise distribution throughout the entire duct space, preventing issues such as incomplete signal coverage or missing characteristics due to the limited location of a single sampling point.

[0071] Figure 3 The diagram shows the air conditioner structure. The fan bearing 3 is located inside the air duct 2 and is the main source of abnormal noise from the fan bearing. The upper end sound wave collector 4 is located at the top of the air duct 2, and the lower end sound wave collector 5 is located at the bottom of the air duct 2. Both of them collect the sound wave signals propagating along the airflow direction within the air duct 2. The upper bearing sound wave collectors 6 are paired on both sides of the upper end of the fan bearing 3, and the lower bearing sound wave collectors 7 are paired on both sides of the lower end of the fan bearing 3. Both of them are close to the noise source and capture the original sound wave signals generated by the operation of the fan bearing 3 at close range.

[0072] The processing unit 102 is configured to identify the type of abnormal noise in the air conditioning duct based on the sound wave signal, the abnormal noise type including fan bearing abnormal noise and thermal stress abnormal noise.

[0073] Abnormal noise from wind turbine bearings is a mechanical noise generated during wind turbine operation due to bearing wear, abnormal clearance, or other issues. It is a periodic, continuous noise with a distinct discrete spectrum, containing one or more fixed fundamental frequencies and their higher harmonics, exhibiting regular fluctuations. Abnormal noise from thermal stress is caused by thermal expansion and contraction during operation, resulting in the compression and deformation of components. It is often sudden, with a wideband energy burst distributed in the 1kHz-8kHz range or even higher. It has poor spectral flatness, lacks a clear fundamental frequency and harmonic structure, and repeats irregularly.

[0074] The acoustic characteristics of fan bearing noise and thermal stress noise differ significantly. The generation mechanisms of these two types of noise are different, and the corresponding noise reduction methods also differ. Early identification of the noise type is a prerequisite for accurate noise reduction. Specifically, the equipment analyzes the collected acoustic signals, distinguishes the noise source by combining signal characteristics, and determines whether the current noise is fan bearing noise or thermal stress noise. Optionally, historical air conditioning operating data can be used to assist in identifying the noise type, comparing the current signal with historical noise data to improve identification accuracy.

[0075] In some embodiments, the processing unit 102 identifies the type of abnormal noise in the air conditioning duct based on the sound wave signal, including: when there is a peak value centered on the motor speed frequency in the spectrum of the sound wave signal, it is determined to be abnormal noise of the fan bearing; when the sound wave signal is a broadband random pulse signal, it is determined to be abnormal noise of thermal stress.

[0076] Fan bearing noise is mechanical noise generated by the periodic friction and collision between the bearing and the shaft during fan operation. The vibration frequency of this type of noise is directly related to the motor's rotational frequency, therefore it exhibits a concentrated peak value centered on the motor's rotational speed in the frequency spectrum, and possesses stable periodic characteristics. Thermal stress noise is noise generated by the expansion and contraction of duct components due to temperature changes, resulting in compression and friction between components. This type of noise has no fixed periodicity; its timing and intensity are random, therefore its sound wave signal appears as a broadband random pulse with a wide frequency distribution and unconcentrated energy. The spectral characteristics of these two types of noise differ significantly, allowing for rapid and accurate differentiation of noise types.

[0077] Specifically, the equipment performs spectral analysis on the acquired acoustic signals to determine the frequency distribution characteristics of the signals. When there is a significant peak in the spectrum of the acoustic signal centered on the motor speed frequency, the abnormal noise corresponding to the signal is identified as abnormal noise from the fan bearing; when the acoustic signal presents a broadband random pulse pattern without a fixed frequency center, the abnormal noise corresponding to the signal is identified as abnormal noise from thermal stress.

[0078] The processing unit 102 is also configured to generate an anti-phase sound wave adapted to the type of abnormal noise based on the air conditioning operating parameters and environmental parameters.

[0079] The operating status of the air conditioner and the ambient temperature and humidity directly alter the frequency, intensity, and other characteristics of abnormal noises. Combining these two types of parameters ensures that the generated anti-phase sound wave closely matches the original abnormal noise. Different types of abnormal noises correspond to anti-phase sound waves with different characteristics, thus improving the effectiveness of noise cancellation. Specifically, the equipment retrieves the current air conditioner operating parameters and environmental parameters, combines them with the identified abnormal noise type, and calculates and generates an anti-phase sound wave whose various indicators match the current abnormal noise. An anti-phase sound wave is a sound wave whose phase is completely opposite to the original noise sound wave and whose frequency matches the original noise sound wave. When this sound wave meets the original noise sound wave, they cancel each other out, thereby reducing the overall noise.

[0080] In some embodiments, the parameters of the anti-phase sound wave include frequency, amplitude, and phase; the processing unit 102, the step of generating an anti-phase sound wave adapted to the type of abnormal noise based on the air conditioner operating parameters and environmental parameters, includes: coupling the air conditioner operating parameters and the environmental parameters to calculate, determining the parameters of the anti-phase sound wave, and generating an anti-phase sound wave of the corresponding frequency band.

[0081] Specifically, the system retrieves current air conditioning operating parameters and environmental parameters, couples these two types of data for calculation, and determines the frequency, amplitude, and phase of the anti-phase sound wave based on the calculation results. Ultimately, it generates an anti-phase sound wave in the corresponding frequency band that matches the current abnormal noise type. Air conditioning operating parameters include the number of fan blades, indoor fan speed, fan blade length, and set air conditioning temperature. Environmental parameters include the current indoor ambient temperature and humidity. Air conditioning operating parameters directly affect the frequency and intensity of the abnormal noise, while environmental parameters affect the vibration characteristics of the duct components and the sound wave propagation state. Coupled calculation of these two types of parameters comprehensively considers the dynamic changes in equipment operation and the environment, ensuring that the generated anti-phase sound wave highly matches the current abnormal noise characteristics, thus improving the effectiveness and stability of noise reduction.

[0082] In some embodiments, the system dynamically calculates the anti-phase sound wave based on the initially received abnormal noise waveform, combined with multi-dimensional physical parameters such as fan blade parameters and ambient temperature and humidity, in an algorithm model, rather than relying on a fixed frequency. The system reads air conditioning data, including the number of fan blades N, indoor fan speed w, fan blade length l, current indoor ambient temperature Tin, indoor ambient humidity RH, and air conditioning set operating temperature Top. It then outputs the anti-phase sound wave. Y = Asin(2Πf*t+θ) ,in f The fundamental frequency of the noise (determined by the number of blades N and the internal fan speed w, f=nw); A The amplitude value (related to the blade length l and aerophysical properties); t For the sound propagation time; θ This is the waveform compensation value (used to compensate for the propagation delay during the sound wave collector's reception of sound). θ=2Πfd / v ,in d To propagate straight-line distance, v The speed of sound (which mainly depends on the ambient temperature Tin, and is corrected according to the ideal gas law to be v≈331.4+0.6×Tin).

[0083] The output unit 103 is configured to output the anti-phase acoustic wave into the air conditioning duct.

[0084] The abnormal noise mainly propagates within the air conditioning duct. By directly outputting anti-phase sound waves into the duct, sound wave cancellation can be achieved in the main space where noise propagates, maximizing the noise reduction effect. Specifically, the sound-generating device delivers the generated anti-phase sound waves into the air conditioning duct, allowing the anti-phase sound waves to superimpose with the original abnormal noise sound waves within the duct space.

[0085] In some embodiments, the output unit 103 outputs the anti-phase sound wave into the air conditioning duct, including: continuously outputting the anti-phase sound wave for abnormal noise from the fan bearing; and intermittently outputting the anti-phase sound wave for abnormal noise from thermal stress.

[0086] Abnormal noise from the fan bearings is generated by the operation of the fan. This type of noise persists as long as the fan is running, and its frequency and intensity remain relatively stable. Therefore, continuous output ensures that the anti-phase sound wave always acts synchronously with the original noise, guaranteeing the continuity of the noise reduction effect and preventing recurring noise. Thermal stress noise is a sudden, intermittent noise generated by the deformation of duct components due to temperature changes. This type of noise is not continuous. Continuously outputting anti-phase sound waves would not only waste unnecessary energy but may also introduce additional sound interference when the noise disappears. Therefore, intermittent output allows for timely output of anti-phase sound waves to cancel out the noise when it appears, and pauses output when the noise disappears, ensuring noise reduction while reducing equipment power consumption and potential interference. Continuous output refers to the anti-phase sound wave generator emitting anti-phase sound waves into the duct with fixed parameters and without interruption. Intermittent output refers to the anti-phase sound wave generator emitting anti-phase sound waves discontinuously, outputting sound waves during specific periods and pausing output during other periods, resulting in an intermittent output process.

[0087] The output unit 103 is further configured to iteratively adjust the parameters of the anti-phase acoustic wave according to the acoustic wave signal fed back after the output of the anti-phase acoustic wave, until the noise meets the preset conditions.

[0088] Air conditioner operation and environmental conditions change dynamically, altering the characteristics of abnormal noises. Fixed-parameter anti-phase sound waves cannot maintain ideal noise reduction for extended periods. By using feedback signals to form a closed-loop adjustment, noise changes can be dynamically adapted to ensure continuous noise reduction. Specifically, after the anti-phase sound wave is output, the detection equipment again collects the sound wave signal within the air duct as a feedback signal. The equipment compares the feedback signal with preset conditions, continuously correcting the parameters of the anti-phase sound wave, and repeatedly performing adjustments until the noise within the air duct meets the preset standard.

[0089] In some embodiments, the output unit 103 iteratively adjusts the parameters of the anti-phase sound wave according to the sound wave signal fed back after the output of the anti-phase sound wave, including: successively correcting the parameters of the anti-phase sound wave according to the deviation between the feedback sound wave signal and the preset conditions, until the noise meets the preset conditions; the preset conditions are that the noise level of the feedback sound wave signal is lower than a preset threshold, or the noise fluctuation is within a preset range.

[0090] Air conditioning operating conditions, indoor and outdoor ambient temperatures, and fan operation status all change in real time. This causes the frequency, intensity, and other characteristics of abnormal noises within the air duct to change synchronously. Fixed, unchanging anti-phase sound wave parameters cannot maintain an ideal noise reduction effect in the long term. By relying on feedback sound wave signals, the actual noise reduction situation can be monitored in real time. By gradually adjusting parameters, the gap between the actual noise and the standard requirements can be reduced step by step, avoiding abnormal sound wave superposition caused by a one-time large adjustment of parameters.

[0091] Specifically, the equipment continuously collects noise-reduced sound wave signals from within the air duct as feedback signals. It compares various indicators of the feedback signal with preset conditions and calculates the deviation. Based on the obtained deviation results, it successively corrects parameters such as the frequency, amplitude, and phase of the anti-phase sound wave, repeating this process. The parameter adjustment stops when the noise level of the feedback sound wave signal is below a preset threshold, or when noise fluctuations remain within a preset range. Noise level is a comprehensive indicator that measures the intensity, amplitude, and energy of noise generated by sound waves, comprehensively characterizing the overall noise state within the air conditioning duct, including sound pressure level and vibration amplitude. Noise fluctuations refer to the ups and downs in the noise level of the sound wave signal during continuous acquisition, reflecting the stability of the noise state.

[0092] In some embodiments, the location for the first acquisition of acoustic signals is different from the location for acquisition of acoustic signals during subsequent iterative adjustments; the initial acquisition location includes the upper end of the air duct, the left side of the upper bearing, and the left side of the lower bearing, while the subsequent acquisition locations include the lower end of the air duct, the right side of the upper bearing, and the right side of the lower bearing.

[0093] Abnormal noises generated by the fan bearings propagate simultaneously to both sides of the bearing and the upper and lower areas of the duct. The phase, amplitude, and propagation loss of the noise received at different locations show significant differences. Initially, signals are collected at the upper end of the duct and the left side of the bearing. This prioritizes capturing the original signal along the initial noise propagation path, ensuring the basic accuracy of initial abnormal noise identification and anti-phase sound wave generation. In subsequent parameter iteration and adjustment phases, signals are collected at the lower end of the duct and the right side of the bearing. This allows for the detection of the noise's propagation through the duct space and its actual state after being superimposed and canceled by anti-phase sound waves, providing another dimension for evaluating the overall noise reduction effect. The signals from these two different areas complement each other, avoiding the problem of single signal data and distorted detection results caused by long-term use of the same set of sampling points due to factors such as local sound wave reflection, airflow interference, and equipment aging. This provides a more comprehensive basis for parameter iteration and adjustment.

[0094] Specifically, during the initial startup of the air conditioning noise reduction process, the signal acquisition equipment collects sound wave signals at three locations: the upper end of the air duct, the left side of the upper bearing, and the left side of the lower bearing. These signals are used to identify the type of abnormal noise, generate and initially output anti-phase sound waves. Once the anti-phase sound wave parameter iterative adjustment phase begins, the system automatically switches the acquisition points, ceasing signal acquisition at the original locations and instead acquiring sound wave signals at the lower end of the air duct, the right side of the upper bearing, and the right side of the lower bearing. This newly acquired set of signals is then used as feedback data to continuously correct the parameters.

[0095] Since the processing and functions implemented by the device in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0096] The technical solution of this invention first collects sound wave signals from multiple points within the air duct to identify abnormal noises from the fan bearings or thermal stress; then, it combines air conditioning operation and environmental data to generate targeted anti-phase sound waves and sends them into the air duct; finally, iteratively optimizes the sound wave parameters through feedback signals until noise reduction meets the standards. This achieves precise processing of two types of noise with different causes, significantly improving the reliability and scene adaptability of the noise reduction effect.

[0097] According to an embodiment of the present invention, an air conditioner corresponding to a noise reduction device for an air conditioner is also provided. This air conditioner may include the noise reduction device described above.

[0098] Since the processing and functions implemented by the air conditioner in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned device, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0099] The technical solution of this invention employs a process of multi-location acoustic wave acquisition, dual-type abnormal noise identification, multi-parameter coupling to generate anti-phase acoustic waves, and closed-loop feedback adjustment to achieve differentiated noise reduction. Compared with traditional fixed-mode noise reduction, it significantly improves noise reduction adaptability and can maintain a stable noise reduction effect even when equipment operating conditions and the environment change dynamically.

[0100] According to an embodiment of the present invention, a storage medium corresponding to a noise reduction method for an air conditioner is also provided, the storage medium including a stored program, wherein the program controls the device where the storage medium is located to execute the noise reduction method for the air conditioner described above when it is running.

[0101] Since the processing and functions implemented by the storage medium in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0102] The technical solution of this invention first collects multi-point sound wave signals to comprehensively capture noise characteristics, then identifies the type of abnormal noise and generates a suitable anti-phase sound wave, and finally dynamically optimizes the sound wave parameters through feedback signals to form a complete noise reduction closed loop. This effectively reduces the two main types of noise during air conditioner operation, improves the quietness of equipment operation and user experience, and ensures the stability of the noise reduction effect.

[0103] According to an embodiment of the present invention, a computer program product corresponding to a noise reduction method for an air conditioner is also provided. The computer program product includes a computer program that, when processed and executed, implements the steps of the noise reduction method for the air conditioner described above.

[0104] Since the processing and functions implemented by the computer program product in this embodiment are basically corresponding to the embodiments, principles and examples of the aforementioned methods, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0105] By employing the technical solution of this invention, effective suppression of abnormal noise from wind turbine bearings and thermal stress is achieved through multi-point data acquisition, precise identification, adaptive generation, and closed-loop adjustment. This not only improves the accuracy of noise reduction but also enhances adaptability to complex operating conditions, avoiding the problem of easy attenuation of noise reduction effects with fixed parameters, and significantly improving overall practicality.

[0106] In summary, it is readily understood by those skilled in the art that, without conflict, the aforementioned advantageous methods can be freely combined and superimposed.

[0107] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for noise reduction in an air conditioner, characterized in that, The method includes: Collect acoustic signals from at least two locations within the air conditioning duct; The abnormal noise type in the air conditioning duct is identified based on the sound wave signal. The abnormal noise type includes abnormal noise from the fan bearing and abnormal noise from thermal stress. Based on the air conditioning operating parameters and environmental parameters, generate an anti-phase sound wave that is adapted to the type of abnormal noise; The anti-phase sound wave is output into the air conditioning duct; The parameters of the anti-phase acoustic wave are iteratively adjusted based on the acoustic wave signal fed back after the output of the anti-phase acoustic wave until the noise meets the preset conditions.

2. The noise reduction method for an air conditioner according to claim 1, characterized in that, The acoustic signals include acoustic signals from both sides of the fan bearing, as well as acoustic signals from upstream and downstream of the fan along the airflow direction within the duct.

3. The noise reduction method for an air conditioner according to claim 1 or 2, characterized in that, The step of identifying the type of abnormal noise in the air conditioning duct based on the sound wave signal includes: When the frequency of the sound wave signal has a peak centered on the motor speed, it is determined to be abnormal noise from the fan bearing. When the acoustic signal is a broadband random pulse signal, it is determined to be thermal stress noise.

4. The noise reduction method for an air conditioner according to claim 1, characterized in that, The parameters of the antiphase acoustic wave include frequency, amplitude, and phase; The process of generating an anti-phase sound wave adapted to the type of abnormal noise based on air conditioning operating parameters and environmental parameters includes: The air conditioning operating parameters are coupled with the environmental parameters to calculate and determine the parameters of the anti-phase sound wave, thereby generating an anti-phase sound wave of the corresponding frequency band.

5. The noise reduction method for an air conditioner according to claim 1, characterized in that, The step of outputting the anti-phase sound wave into the air conditioning duct includes: For abnormal noise from the fan bearing, the anti-phase sound wave is continuously output; for abnormal noise from thermal stress, the anti-phase sound wave is intermittently output.

6. The noise reduction method for an air conditioner according to claim 1, characterized in that, The step of iteratively adjusting the parameters of the anti-phase acoustic wave based on the acoustic wave signal fed back after the output of the anti-phase acoustic wave includes: Based on the deviation between the feedback acoustic signal and the preset conditions, the parameters of the antiphase acoustic wave are successively corrected until the noise meets the preset conditions; the preset conditions are that the noise level of the feedback acoustic signal is lower than a preset threshold or the noise fluctuation is within a preset range.

7. A noise reduction device for an air conditioner, characterized in that, include: The acquisition unit is configured to acquire acoustic signals from at least two locations within the air conditioning duct. The processing unit is configured to identify the type of abnormal noise in the air conditioning duct based on the sound wave signal, the abnormal noise type including fan bearing abnormal noise and thermal stress abnormal noise; The processing unit is also configured to generate an anti-phase sound wave adapted to the type of abnormal noise based on the air conditioning operating parameters and environmental parameters. The output unit is configured to output the anti-phase acoustic wave into the air conditioning duct. The output unit is further configured to iteratively adjust the parameters of the anti-phase acoustic wave based on the acoustic wave signal fed back after the output of the anti-phase acoustic wave, until the noise meets a preset condition.

8. An air conditioner, characterized in that, include: The noise reduction device for an air conditioner as described in claim 7.

9. A storage medium, characterized in that, The storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the storage medium to perform the noise reduction method of the air conditioner according to any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the noise reduction method for the air conditioner according to any one of claims 1 to 6.

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