Heat pump leakage explosion-proof method and device

Abstract

The present invention discloses a heat pump leakage explosion prevention method and device, comprising: detecting gas concentration based on concentration sensors uniformly arranged on heat pump pipelines and determining whether it is greater than a preset gas concentration threshold; determining and marking the location where the gas concentration is greater than the preset gas concentration threshold, and collecting sound signals at the marked locations; determining the refrigerant leakage area based on the sound signals; evaluating the explosion risk value of the refrigerant leakage area and comparing it with a preset explosion risk threshold; when it is determined that the explosion risk value is less than the preset explosion risk threshold, controlling the heat pump to stop working and opening the inert gas storage tank to introduce inert gas into the refrigerant leakage area; and when it is determined that the explosion risk value is greater than or equal to the preset explosion risk threshold, issuing a warning message to stay away from the heat pump. The refrigerant leakage area is quickly and accurately determined, and corresponding treatment measures are given based on the explosion risk of the refrigerant leakage area to eliminate safety hazards.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pump monitoring, and in particular to a heat pump leakage explosion-proof method and device. Background Art

[0002] With the booming heat pump market in recent years, the popularity of heat pump equipment has increased significantly. Consequently, market maintenance requirements have become increasingly frequent. Due to significant design differences between manufacturers, after-sales service issues are also numerous. The most significant issue is refrigerant leaks in the fluorine circuit system, which are often located in pipe welds, needle valves, elbows, and copper pipe holes. Most manufacturers detect refrigerant leaks in fluorine circuit systems simply by checking whether the compressor suction pressure switch is closed. However, heat pump equipment, in order to achieve stable heating at ultra-low temperatures, typically uses a suction pressure switch with a relatively low operating pressure threshold. This means that the suction pressure switch only requires a very small amount of refrigerant pressure to maintain its closed state. Therefore, when a refrigerant leak occurs in the system, a significant amount of refrigerant must leak before the suction pressure switch reaches its open state. At this point, the compressor has been operating at low refrigerant levels for a long time, which can lead to poor cooling of the compressor motor, causing it to burn out and short-circuit, or carbonizing the compressor lubricant due to high temperatures, resulting in poor lubrication and wear, and ultimately, compressor seizure. The existing technology is unable to quickly and accurately determine the refrigerant leakage area, and is also unable to provide corresponding treatment measures based on the explosion risk of the refrigerant leakage area, which poses certain safety hazards. Summary of the Invention

[0003] The present invention aims to at least partially address one of the above-mentioned technical problems. To this end, the first object of the present invention is to provide a heat pump leakage explosion prevention method that quickly and accurately identifies the refrigerant leakage area and, based on the explosion risk of the refrigerant leakage area, provides corresponding treatment measures to eliminate safety hazards.

[0004] The second object of the present invention is to provide a leakage and explosion-proof device for a heat pump.

[0005] To achieve the above objectives, a first embodiment of the present invention provides a leakage and explosion prevention method for a heat pump, comprising:

[0006] The gas concentration is detected by the concentration sensors evenly arranged on the heat pump pipes, and it is determined whether it is greater than the preset gas concentration threshold;

[0007] Determine and mark the location where the gas concentration is greater than a preset gas concentration threshold, and collect sound signals at the marked location;

[0008] Determine the refrigerant leakage area based on sound signals;

[0009] Assess the explosion risk value of the refrigerant leakage area and compare it with the preset explosion risk threshold;

[0010] When it is determined that the explosion risk value is less than the preset explosion risk threshold, the heat pump is controlled to stop working and the inert gas storage tank is opened to introduce inert gas into the refrigerant leakage area; when it is determined that the explosion risk value is greater than or equal to the preset explosion risk threshold, a warning message to stay away from the heat pump is issued.

[0011] According to some embodiments of the present invention, determining a refrigerant leakage area based on a sound signal includes:

[0012] Preprocessing the sound signal to obtain a preprocessed sound signal;

[0013] The refrigerant leakage area is determined based on the preprocessed sound signal and sound source localization method.

[0014] According to some embodiments of the present invention, preprocessing a sound signal to obtain a preprocessed sound signal includes:

[0015] Perform frame division, windowing and short-time Fourier transform on the sound signal to obtain the frequency domain sound signal;

[0016] Performing signal segmentation on the frequency domain sound signal to obtain a plurality of frames of sub-frequency domain sound signals, performing frame shift processing on the plurality of frames of sub-frequency domain sound signals to obtain sampling points of the plurality of frames of sub-frequency domain sound signals after the frame shift processing;

[0017] Obtain the spectrum energy of the sampling points of several frames of sub-frequency domain sound signals and compare them with a preset spectrum energy threshold. The sampling points whose frequency energy is less than the preset spectrum energy threshold are regarded as noise points, and the sub-frequency domain sound signals corresponding to the noise points are regarded as noise frames.

[0018] Determine the frequency of maximum spectral energy for each noise frame and set the frequency domain mask weight on the frequency;

[0019] Determine the noise energy of the noise frame according to the frequency domain mask weight, and calculate the noise average value based on the noise energies of several noise frames;

[0020] Based on the noise average value, the noise value-filter coefficient table is queried to obtain the corresponding filter coefficient, and the frequency domain sound signal is subjected to noise reduction processing according to the filter coefficient to obtain a preprocessed sound signal.

[0021] According to some embodiments of the present invention, evaluating the explosion risk value of a refrigerant leakage area includes:

[0022] Determine the gas flow rate Q in the refrigerant leakage area:

[0023]

[0024] Among them, Si is the area of ​​the i-th leakage location in the refrigerant leakage area; P1 is the air pressure in the refrigerant leakage area of ​​the heat pump pipeline before leakage; P2 is the air pressure in the refrigerant leakage area of ​​the heat pump pipeline after leakage; ρ2 is the average gas density detected in the refrigerant leakage area after leakage of the heat pump pipeline; ρ1 is the gas density in the refrigerant leakage area of ​​the heat pump pipeline before leakage; n is the number of leakage locations included in the refrigerant leakage area;

[0025] Assess the explosion risk value of the refrigerant leakage area based on the gas flow rate in the refrigerant leakage area;

[0026]

[0027] Where W is the explosion risk value of the refrigerant leakage area; Q0 is the refrigerant capacity of the refrigerant leakage area of ​​the heat pump pipeline; T i is the explosion risk weight of the i-th leakage location in the refrigerant leakage area; G i is the refrigerant concentration at the i-th leakage location in the refrigerant leakage area.

[0028] According to some embodiments of the present invention, after the inert gas is introduced into the refrigerant leakage area, the method further includes:

[0029] Continuously calculate the explosion risk value for each time period and close the inert gas storage tank when it is determined that the safety level has been reached.

[0030] To achieve the above-mentioned object, a second embodiment of the present invention provides a leakage and explosion-proof device for a heat pump, comprising:

[0031] A judgment module, configured to detect gas concentration based on concentration sensors uniformly arranged on the heat pump pipes, and determine whether the gas concentration is greater than a preset gas concentration threshold;

[0032] A marking module, used to determine and mark the location where the gas concentration is greater than a preset gas concentration threshold, and collect sound signals at the marked location;

[0033] A determination module, used for determining a refrigerant leakage area based on the sound signal;

[0034] An assessment module, used to assess the explosion risk value of the refrigerant leakage area and compare it with a preset explosion risk threshold;

[0035] The control module is used to control the heat pump to stop working and open the inert gas storage tank to introduce inert gas into the refrigerant leakage area when it is determined that the explosion risk value is less than the preset explosion risk threshold; when it is determined that the explosion risk value is greater than or equal to the preset explosion risk threshold, it issues a warning message to stay away from the heat pump.

[0036] According to some embodiments of the present invention, the determining module includes:

[0037] A preprocessing module, used for preprocessing the sound signal to obtain a preprocessed sound signal;

[0038] The positioning module is used to determine the refrigerant leakage area based on the preprocessed sound signal and the sound source positioning method.

[0039] According to some embodiments of the present invention, the preprocessing module includes:

[0040] Compute module for:

[0041] Perform frame division, windowing and short-time Fourier transform on the sound signal to obtain the frequency domain sound signal;

[0042] Performing signal segmentation on the frequency domain sound signal to obtain a plurality of frames of sub-frequency domain sound signals, performing frame shift processing on the plurality of frames of sub-frequency domain sound signals to obtain sampling points of the plurality of frames of sub-frequency domain sound signals after the frame shift processing;

[0043] Obtain the spectrum energy of the sampling points of several frames of sub-frequency domain sound signals and compare them with a preset spectrum energy threshold. The sampling points whose frequency energy is less than the preset spectrum energy threshold are regarded as noise points, and the sub-frequency domain sound signals corresponding to the noise points are regarded as noise frames.

[0044] Determine the frequency of maximum spectral energy for each noise frame and set the frequency domain mask weight on the frequency;

[0045] Determine the noise energy of the noise frame according to the frequency domain mask weight, and calculate the noise average value based on the noise energies of several noise frames;

[0046] The noise reduction module is used to query the noise value-filter coefficient table based on the noise average value, obtain the corresponding filter coefficient, and perform noise reduction processing on the frequency domain sound signal according to the filter coefficient to obtain a preprocessed sound signal.

[0047] According to some embodiments of the present invention, the assessment module assesses the explosion risk value of the refrigerant leakage area, including:

[0048] Determine the gas flow rate Q in the refrigerant leakage area:

[0049]

[0050] Among them, S i is the area of ​​the i-th leakage location in the refrigerant leakage area; P1 is the air pressure in the refrigerant leakage area of ​​the heat pump pipeline before leakage; P2 is the air pressure in the refrigerant leakage area of ​​the heat pump pipeline after leakage; ρ2 is the average gas density detected in the refrigerant leakage area after leakage of the heat pump pipeline; ρ1 is the gas density in the refrigerant leakage area of ​​the heat pump pipeline before leakage; n is the number of leakage locations included in the refrigerant leakage area;

[0051] Assess the explosion risk value of the refrigerant leakage area based on the gas flow rate in the refrigerant leakage area;

[0052]

[0053] Where W is the explosion risk value of the refrigerant leakage area; Q0 is the refrigerant capacity of the refrigerant leakage area of ​​the heat pump pipeline; T i is the explosion risk weight of the i-th leakage location in the refrigerant leakage area; G i is the refrigerant concentration at the i-th leakage location in the refrigerant leakage area.

[0054] According to some embodiments of the present invention, the system further includes: a statistical module for continuously counting the explosion risk value in each time period after the inert gas is introduced into the refrigerant leakage area, and closing the inert gas storage tank when it is determined that the safety level has been reached.

[0055] The present invention proposes a leakage explosion-proof method and device for a heat pump, which can quickly and accurately determine the refrigerant leakage area, and at the same time provide corresponding treatment measures according to the explosion risk of the refrigerant leakage area to eliminate safety hazards.

[0056] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0057] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0059] Figure 1 This is a flow chart of a heat pump leakage and explosion prevention method according to one embodiment of the present invention;

[0060] Figure 2 4 is a block diagram of a leakage and explosion-proof device for a heat pump according to an embodiment of the present invention. DETAILED DESCRIPTION

[0061] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0062] like Figure 1As shown, the first embodiment of the present invention provides a leakage explosion-proof method for a heat pump, comprising steps S1-S5:

[0063] S1. Detecting gas concentration using concentration sensors evenly arranged on heat pump pipes and determining whether the gas concentration is greater than a preset gas concentration threshold;

[0064] S2. Determine and mark the location where the gas concentration is greater than a preset gas concentration threshold, and collect sound signals at the marked location;

[0065] S3. Determine the refrigerant leakage area based on the sound signal;

[0066] S4. Evaluate the explosion risk value of the refrigerant leakage area and compare it with the preset explosion risk threshold;

[0067] S5. When it is determined that the explosion risk value is less than the preset explosion risk threshold, the heat pump is controlled to stop working and the inert gas storage tank is opened to introduce inert gas into the refrigerant leakage area; when it is determined that the explosion risk value is greater than or equal to the preset explosion risk threshold, a warning message is issued to stay away from the heat pump.

[0068] The working principle of the above technical solution: In this embodiment, concentration sensors are evenly arranged on the heat pump pipeline to detect the gas concentration. The location information where the gas concentration is greater than the preset gas concentration threshold is determined and marked as an abnormal location. The sound signal of the marked location is collected; the refrigerant leakage area is determined based on the sound signal; the explosion risk value of the refrigerant leakage area is evaluated and compared with the preset explosion risk threshold; when it is determined that the explosion risk value is less than the preset explosion risk threshold, the heat pump is controlled to stop working and the inert gas storage tank is opened to introduce inert gas into the refrigerant leakage area; ventilation holes are opened in the bottom sheet metal of the compressor compartment of the heat pump to reduce the concentration of the refrigerant R290 through a large amount of inert gas. When it is determined that the explosion risk value is greater than or equal to the preset explosion risk threshold, a warning message to stay away from the heat pump is issued. Avoid people approaching the heat pump area to reduce risks.

[0069] The beneficial effects of the above technical solution are: quickly and accurately determining the refrigerant leakage area, and at the same time, providing corresponding treatment measures based on the explosion risk of the refrigerant leakage area to eliminate safety hazards.

[0070] According to some embodiments of the present invention, determining a refrigerant leakage area based on a sound signal includes:

[0071] Preprocessing the sound signal to obtain a preprocessed sound signal;

[0072] The refrigerant leakage area is determined based on the preprocessed sound signal and sound source localization method.

[0073] The working principle of the above technical solution is as follows: The purpose of sound signal preprocessing is to improve the accuracy and reliability of subsequent analysis. This includes operations such as noise reduction, filtering, amplification, and normalization. Noise reduction reduces background noise and other irrelevant signals, filtering removes unnecessary frequency components, and amplification and normalization make the signal more suitable for further analysis. Sound source localization methods, such as the frequency cepstrum method, determine the direction of the sound source by analyzing the frequency characteristics of the sound. This is often combined with machine learning algorithms to achieve sound source localization.

[0074] The beneficial effect of the above technical solution is that the refrigerant leakage area can be accurately determined based on the pre-processed sound signal and the sound source positioning method.

[0075] According to some embodiments of the present invention, preprocessing a sound signal to obtain a preprocessed sound signal includes:

[0076] Perform frame division, windowing and short-time Fourier transform on the sound signal to obtain the frequency domain sound signal;

[0077] Performing signal segmentation on the frequency domain sound signal to obtain a plurality of frames of sub-frequency domain sound signals, performing frame shift processing on the plurality of frames of sub-frequency domain sound signals to obtain sampling points of the plurality of frames of sub-frequency domain sound signals after the frame shift processing;

[0078] Obtain the spectrum energy of the sampling points of several frames of sub-frequency domain sound signals and compare them with a preset spectrum energy threshold. The sampling points whose frequency energy is less than the preset spectrum energy threshold are regarded as noise points, and the sub-frequency domain sound signals corresponding to the noise points are regarded as noise frames.

[0079] Determine the frequency of maximum spectral energy for each noise frame and set the frequency domain mask weight on the frequency;

[0080] Determine the noise energy of the noise frame according to the frequency domain mask weight, and calculate the noise average value based on the noise energies of several noise frames;

[0081] Based on the noise average value, the noise value-filter coefficient table is queried to obtain the corresponding filter coefficient, and the frequency domain sound signal is subjected to noise reduction processing according to the filter coefficient to obtain a preprocessed sound signal.

[0082] The working principle and beneficial effects of the above technical solution: In this embodiment, the sound signal is framed, windowed and short-time Fourier transformed to obtain a frequency domain sound signal, including: dividing the continuous sound signal into multiple time windows, each time window is called a frame. Framing is usually performed in an overlapping manner, that is, there is a partial overlap between adjacent frames to ensure the continuity of the signal. The signal of each frame is windowed and multiplied by a certain window function (such as Hamming window, Hanning window, etc.) to reduce spectrum leakage and reduce the interference of window boundaries on spectrum estimation. The signal after each frame is windowed is Fourier transformed to obtain a frequency domain representation of the frame. STFT can help us analyze the frequency characteristics of the signal in the frequency domain and the time-varying characteristics in the time domain.

[0083] In this embodiment, the sampling points of the sub-frequency domain sound signal of several frames after frame shift processing facilitate the determination of signal segmentation points, ensuring the continuity and accuracy of the signal data. A preset spectral energy threshold is used to determine whether it is an energy threshold for a noise point. The spectral energy of the sampling points of the sub-frequency domain sound signal of several frames is obtained and compared with the preset spectral energy threshold. The sampling points with frequency energy less than the preset spectral energy threshold are regarded as noise points, and the sub-frequency domain sound signal corresponding to the noise point is regarded as a noise frame, thereby accurately determining the noise frame.

[0084] In this embodiment, the frequency with maximum spectral energy is determined for each noise frame: For each frequency domain frame identified as noise, the energy of each frequency component in the spectrum (typically the result of an FFT) is calculated. The frequency component with the highest energy is found. This typically corresponds to the dominant frequency component in the noise. A frequency domain mask weight is set at that frequency: Once the frequency with maximum energy is determined, a mask or weight can be set at that frequency (or within a range around it) to reduce or eliminate the impact of that frequency component. The mask weight can be set based on the specific situation; for example, the frequency can be completely blocked (weight 0) or its energy can be partially reduced (0 < weight < 1). The noise energy of the noise frame is determined based on the frequency domain mask weight: After applying the mask weight, the energy of each noise frame is recalculated. This typically involves multiplying the mask weight by the original spectrum and then summing the values ​​to obtain an adjusted energy value. Based on the noise energies of several noise frames, a noise average is calculated: The energies of multiple noise frames are averaged to obtain a representative noise energy value. This average can be used as a reference for subsequent noise reduction or signal enhancement. Identify and reduce specific noise components in the audio signal. At the same time, based on the determined noise average value, query the noise value-filter coefficient table to obtain the corresponding filter coefficient. Perform noise reduction processing on the frequency domain sound signal according to the filter coefficient to achieve secondary noise reduction, further improve the accuracy of noise reduction, and obtain a preprocessed sound signal.

[0085] According to some embodiments of the present invention, evaluating the explosion risk value of a refrigerant leakage area includes:

[0086] Determine the gas flow rate Q in the refrigerant leakage area:

[0087]

[0088] Among them, S i is the area of ​​the i-th leakage location in the refrigerant leakage area; P1 is the air pressure in the refrigerant leakage area of ​​the heat pump pipeline before leakage; P2 is the air pressure in the refrigerant leakage area of ​​the heat pump pipeline after leakage; ρ2 is the average gas density detected in the refrigerant leakage area after leakage of the heat pump pipeline; ρ1 is the gas density in the refrigerant leakage area of ​​the heat pump pipeline before leakage; n is the number of leakage locations included in the refrigerant leakage area;

[0089] Assess the explosion risk value of the refrigerant leakage area based on the gas flow rate in the refrigerant leakage area;

[0090]

[0091] Where W is the explosion risk value of the refrigerant leakage area; Q0 is the refrigerant capacity of the refrigerant leakage area of ​​the heat pump pipeline; T i is the explosion risk weight of the i-th leakage location in the refrigerant leakage area; G i is the refrigerant concentration at the i-th leakage location in the refrigerant leakage area.

[0092] The working principle and beneficial effects of the above technical solution are as follows: determining the gas flow rate in the refrigerant leakage area, and evaluating the explosion risk value of the refrigerant leakage area based on the gas flow rate in the refrigerant leakage area; based on the above algorithm, accurately calculating the explosion risk value of the refrigerant leakage area, improving the accuracy of judging the explosion risk value and the preset explosion risk threshold, thereby facilitating the provision of accurate treatment measures and reducing safety hazards.

[0093] According to some embodiments of the present invention, after the inert gas is introduced into the refrigerant leakage area, the method further includes:

[0094] Continuously calculate the explosion risk value for each time period and close the inert gas storage tank when it is determined that the safety level has been reached.

[0095] like Figure 2 As shown, the second embodiment of the present invention provides a leakage and explosion-proof device for a heat pump, comprising:

[0096] A judgment module, configured to detect gas concentration based on concentration sensors uniformly arranged on the heat pump pipes, and determine whether the gas concentration is greater than a preset gas concentration threshold;

[0097] A marking module, used to determine and mark the location where the gas concentration is greater than a preset gas concentration threshold, and collect sound signals at the marked location;

[0098] A determination module, used for determining a refrigerant leakage area based on the sound signal;

[0099] An assessment module, used to assess the explosion risk value of the refrigerant leakage area and compare it with a preset explosion risk threshold;

[0100] The control module is used to control the heat pump to stop working and open the inert gas storage tank to introduce inert gas into the refrigerant leakage area when it is determined that the explosion risk value is less than the preset explosion risk threshold; when it is determined that the explosion risk value is greater than or equal to the preset explosion risk threshold, it issues a warning message to stay away from the heat pump.

[0101] The working principle of the above technical solution: In this embodiment, concentration sensors are evenly arranged on the heat pump pipeline to detect the gas concentration. The location information where the gas concentration is greater than the preset gas concentration threshold is determined and marked as an abnormal location. The sound signal of the marked location is collected; the refrigerant leakage area is determined based on the sound signal; the explosion risk value of the refrigerant leakage area is evaluated and compared with the preset explosion risk threshold; when it is determined that the explosion risk value is less than the preset explosion risk threshold, the heat pump is controlled to stop working and the inert gas storage tank is opened to introduce inert gas into the refrigerant leakage area; ventilation holes are opened in the bottom sheet metal of the compressor compartment of the heat pump to reduce the concentration of the refrigerant R290 through a large amount of inert gas. When it is determined that the explosion risk value is greater than or equal to the preset explosion risk threshold, a warning message to stay away from the heat pump is issued. Avoid people approaching the heat pump area to reduce risks.

[0102] The beneficial effects of the above technical solution are: quickly and accurately determining the refrigerant leakage area, and at the same time, providing corresponding treatment measures based on the explosion risk of the refrigerant leakage area to eliminate safety hazards.

[0103] According to some embodiments of the present invention, the determining module includes:

[0104] A preprocessing module, used for preprocessing the sound signal to obtain a preprocessed sound signal;

[0105] The positioning module is used to determine the refrigerant leakage area based on the preprocessed sound signal and the sound source positioning method.

[0106] The working principle of the above technical solution is as follows: The purpose of sound signal preprocessing is to improve the accuracy and reliability of subsequent analysis. This includes operations such as noise reduction, filtering, amplification, and normalization. Noise reduction reduces background noise and other irrelevant signals, filtering removes unnecessary frequency components, and amplification and normalization make the signal more suitable for further analysis. Sound source localization methods, such as the frequency cepstrum method, determine the direction of the sound source by analyzing the frequency characteristics of the sound. This is often combined with machine learning algorithms to achieve sound source localization.

[0107] The beneficial effect of the above technical solution is that the refrigerant leakage area can be accurately determined based on the pre-processed sound signal and the sound source positioning method.

[0108] According to some embodiments of the present invention, the preprocessing module includes:

[0109] Compute module for:

[0110] Perform frame division, windowing and short-time Fourier transform on the sound signal to obtain the frequency domain sound signal;

[0111] Performing signal segmentation on the frequency domain sound signal to obtain a plurality of frames of sub-frequency domain sound signals, performing frame shift processing on the plurality of frames of sub-frequency domain sound signals to obtain sampling points of the plurality of frames of sub-frequency domain sound signals after the frame shift processing;

[0112] Obtain the spectrum energy of the sampling points of several frames of sub-frequency domain sound signals and compare them with a preset spectrum energy threshold. The sampling points whose frequency energy is less than the preset spectrum energy threshold are regarded as noise points, and the sub-frequency domain sound signals corresponding to the noise points are regarded as noise frames.

[0113] Determine the frequency of maximum spectral energy for each noise frame and set the frequency domain mask weight on the frequency;

[0114] Determine the noise energy of the noise frame according to the frequency domain mask weight, and calculate the noise average value based on the noise energies of several noise frames;

[0115] The noise reduction module is used to query the noise value-filter coefficient table based on the noise average value, obtain the corresponding filter coefficient, and perform noise reduction processing on the frequency domain sound signal according to the filter coefficient to obtain a preprocessed sound signal.

[0116] The working principle and beneficial effects of the above technical solution: In this embodiment, the sound signal is framed, windowed and short-time Fourier transformed to obtain a frequency domain sound signal, including: dividing the continuous sound signal into multiple time windows, each time window is called a frame. Framing is usually performed in an overlapping manner, that is, there is a partial overlap between adjacent frames to ensure the continuity of the signal. The signal of each frame is windowed and multiplied by a certain window function (such as Hamming window, Hanning window, etc.) to reduce spectrum leakage and reduce the interference of window boundaries on spectrum estimation. The signal after each frame is windowed is Fourier transformed to obtain a frequency domain representation of the frame. STFT can help us analyze the frequency characteristics of the signal in the frequency domain and the time-varying characteristics in the time domain.

[0117] In this embodiment, the sampling points of the sub-frequency domain sound signal of several frames after frame shift processing facilitate the determination of signal segmentation points, ensuring the continuity and accuracy of the signal data. A preset spectral energy threshold is used to determine whether it is an energy threshold for a noise point. The spectral energy of the sampling points of the sub-frequency domain sound signal of several frames is obtained and compared with the preset spectral energy threshold. The sampling points with frequency energy less than the preset spectral energy threshold are regarded as noise points, and the sub-frequency domain sound signal corresponding to the noise point is regarded as a noise frame, thereby accurately determining the noise frame.

[0118] In this embodiment, the frequency with maximum spectral energy is determined for each noise frame: For each frequency domain frame identified as noise, the energy of each frequency component in the spectrum (typically the result of an FFT) is calculated. The frequency component with the highest energy is found. This typically corresponds to the dominant frequency component in the noise. A frequency domain mask weight is set at that frequency: Once the frequency with maximum energy is determined, a mask or weight can be set at that frequency (or within a range around it) to reduce or eliminate the impact of that frequency component. The mask weight can be set based on the specific situation; for example, the frequency can be completely blocked (weight 0) or its energy can be partially reduced (0 < weight < 1). The noise energy of the noise frame is determined based on the frequency domain mask weight: After applying the mask weight, the energy of each noise frame is recalculated. This typically involves multiplying the mask weight by the original spectrum and then summing the values ​​to obtain an adjusted energy value. Based on the noise energies of several noise frames, a noise average is calculated: The energies of multiple noise frames are averaged to obtain a representative noise energy value. This average can be used as a reference for subsequent noise reduction or signal enhancement. Identify and reduce specific noise components in the audio signal. At the same time, based on the determined noise average value, query the noise value-filter coefficient table to obtain the corresponding filter coefficient. Perform noise reduction processing on the frequency domain sound signal according to the filter coefficient to achieve secondary noise reduction, further improve the accuracy of noise reduction, and obtain a preprocessed sound signal.

[0119] According to some embodiments of the present invention, the assessment module assesses the explosion risk value of the refrigerant leakage area, including:

[0120] Determine the gas flow rate Q in the refrigerant leakage area:

[0121]

[0122] Among them, S i is the area of ​​the i-th leakage location in the refrigerant leakage area; P1 is the air pressure in the refrigerant leakage area of ​​the heat pump pipeline before leakage; P2 is the air pressure in the refrigerant leakage area of ​​the heat pump pipeline after leakage; ρ2 is the average gas density detected in the refrigerant leakage area after leakage of the heat pump pipeline; ρ1 is the gas density in the refrigerant leakage area of ​​the heat pump pipeline before leakage; n is the number of leakage locations included in the refrigerant leakage area;

[0123] Assess the explosion risk value of the refrigerant leakage area based on the gas flow rate in the refrigerant leakage area;

[0124]

[0125] Where W is the explosion risk value of the refrigerant leakage area; Q0 is the refrigerant capacity of the refrigerant leakage area of ​​the heat pump pipeline; T i is the explosion risk weight of the i-th leakage location in the refrigerant leakage area; G i is the refrigerant concentration at the i-th leakage location in the refrigerant leakage area.

[0126] The working principle and beneficial effects of the above technical solution are as follows: determining the gas flow rate in the refrigerant leakage area, and evaluating the explosion risk value of the refrigerant leakage area based on the gas flow rate in the refrigerant leakage area; based on the above algorithm, accurately calculating the explosion risk value of the refrigerant leakage area, improving the accuracy of judging the explosion risk value and the preset explosion risk threshold, thereby facilitating the provision of accurate treatment measures and reducing safety hazards.

[0127] According to some embodiments of the present invention, the system further includes: a statistical module for continuously counting the explosion risk value in each time period after the inert gas is introduced into the refrigerant leakage area, and closing the inert gas storage tank when it is determined that the safety level has been reached.

[0128] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A heat pump leakage explosion prevention method, characterized in that: include: The gas concentration is detected by the concentration sensors evenly arranged on the heat pump pipes, and it is determined whether it is greater than the preset gas concentration threshold; Determine and mark the location where the gas concentration is greater than a preset gas concentration threshold, and collect sound signals at the marked location; Determine the refrigerant leakage area based on sound signals; Assess the explosion risk value of the refrigerant leakage area and compare it with the preset explosion risk threshold; When it is determined that the explosion risk value is less than the preset explosion risk threshold, the heat pump is controlled to stop working and the inert gas storage tank is opened to introduce inert gas into the refrigerant leakage area; When it is determined that the explosion risk value is greater than or equal to the preset explosion risk threshold, a warning message to stay away from the heat pump is issued; Assess the explosion risk in the refrigerant leak area, including: Determine the gas flow rate in the refrigerant leak area; Assess the explosion risk value of the refrigerant leakage area based on the gas flow rate in the refrigerant leakage area; in, is the gas flow rate in the refrigerant leakage area; is the explosion risk value of the refrigerant leakage area; The refrigerant capacity of the refrigerant leakage area of ​​the heat pump pipeline; is the explosion risk weight of the i-th leakage location in the refrigerant leakage area; is the refrigerant concentration at the i-th leakage location in the refrigerant leakage area; The number of leakage locations included in the refrigerant leakage area.

2. The heat pump leakage explosion prevention method according to claim 1, characterized in that: Determine the refrigerant leakage area based on sound signals, including: Preprocessing the sound signal to obtain a preprocessed sound signal; The refrigerant leakage area is determined based on the preprocessed sound signal and sound source localization method.

3. The heat pump leakage explosion prevention method according to claim 2, characterized in that: Preprocessing the sound signal to obtain a preprocessed sound signal includes: Perform frame division, windowing and short-time Fourier transform on the sound signal to obtain the frequency domain sound signal; Performing signal segmentation on the frequency domain sound signal to obtain a plurality of frames of sub-frequency domain sound signals, performing frame shift processing on the plurality of frames of sub-frequency domain sound signals to obtain sampling points of the plurality of frames of sub-frequency domain sound signals after the frame shift processing; Obtain the spectrum energy of the sampling points of several frames of sub-frequency domain sound signals and compare them with a preset spectrum energy threshold. The sampling points whose frequency energy is less than the preset spectrum energy threshold are regarded as noise points, and the sub-frequency domain sound signals corresponding to the noise points are regarded as noise frames. Determine the frequency of maximum spectral energy for each noise frame and set the frequency domain mask weight on the frequency; Determine the noise energy of the noise frame according to the frequency domain mask weight, and calculate the noise average value based on the noise energies of several noise frames; Based on the noise average value, the noise value-filter coefficient table is queried to obtain the corresponding filter coefficient, and the frequency domain sound signal is subjected to noise reduction processing according to the filter coefficient to obtain a preprocessed sound signal.

4. The heat pump leakage explosion prevention method according to claim 1, characterized in that: After inert gas is introduced into the refrigerant leakage area, the following steps are also required: Continuously calculate the explosion risk value for each time period and close the inert gas storage tank when it is determined that the safety level has been reached.

5. A heat pump leakage and explosion-proof device, characterized in that: include: A judgment module, configured to detect gas concentration based on concentration sensors uniformly arranged on the heat pump pipes, and determine whether the gas concentration is greater than a preset gas concentration threshold; A marking module, used to determine and mark the location where the gas concentration is greater than a preset gas concentration threshold, and collect sound signals at the marked location; A determination module, used for determining a refrigerant leakage area based on the sound signal; An assessment module, used to assess the explosion risk value of the refrigerant leakage area and compare it with a preset explosion risk threshold; The control module is used to control the heat pump to stop working and open the inert gas storage tank to introduce inert gas into the refrigerant leakage area when it is determined that the explosion risk value is less than a preset explosion risk threshold; When it is determined that the explosion risk value is greater than or equal to the preset explosion risk threshold, a warning message to stay away from the heat pump is issued; The assessment module evaluates the explosion risk value of the refrigerant leakage area, including: Determine the gas flow rate in the refrigerant leak area; Assess the explosion risk value of the refrigerant leakage area based on the gas flow rate in the refrigerant leakage area; in, is the gas flow rate in the refrigerant leakage area; is the explosion risk value of the refrigerant leakage area; The refrigerant capacity of the refrigerant leakage area of ​​the heat pump pipeline; is the explosion risk weight of the i-th leakage location in the refrigerant leakage area; is the refrigerant concentration at the i-th leakage location in the refrigerant leakage area; The number of leakage locations included in the refrigerant leakage area.

6. The heat pump leakage and explosion-proof device according to claim 5, characterized in that: Identify modules, including: A preprocessing module, used for preprocessing the sound signal to obtain a preprocessed sound signal; The positioning module is used to determine the refrigerant leakage area based on the preprocessed sound signal and the sound source positioning method.

7. The heat pump leakage and explosion-proof device according to claim 6, characterized in that: Preprocessing module, including: Compute module for: Perform frame division, windowing and short-time Fourier transform on the sound signal to obtain the frequency domain sound signal; Performing signal segmentation on the frequency domain sound signal to obtain a plurality of frames of sub-frequency domain sound signals, performing frame shift processing on the plurality of frames of sub-frequency domain sound signals to obtain sampling points of the plurality of frames of sub-frequency domain sound signals after the frame shift processing; Obtain the spectrum energy of the sampling points of several frames of sub-frequency domain sound signals and compare them with a preset spectrum energy threshold. The sampling points whose frequency energy is less than the preset spectrum energy threshold are regarded as noise points, and the sub-frequency domain sound signals corresponding to the noise points are regarded as noise frames. Determine the frequency of maximum spectral energy for each noise frame and set the frequency domain mask weight on the frequency; Determine the noise energy of the noise frame according to the frequency domain mask weight, and calculate the noise average value based on the noise energies of several noise frames; The noise reduction module is used to query the noise value-filter coefficient table based on the noise average value, obtain the corresponding filter coefficient, and perform noise reduction processing on the frequency domain sound signal according to the filter coefficient to obtain a preprocessed sound signal.

8. The heat pump leakage and explosion-proof device according to claim 5, characterized in that: Also includes: The statistical module is used to continuously count the explosion risk value in each time period after inert gas is introduced into the refrigerant leakage area, and to close the inert gas storage tank when it is determined that the safety level has been reached.

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