Litchi preservation control method and system based on adjustment of low-frequency electric field

Abstract

The invention discloses a litchi preservation control method and system based on adjustment of a low-frequency electric field. The method relates to the technical field of power supply control, and comprises the following steps: collecting and processing litchi fresh-keeping parameters, analyzing the parameters to obtain a quantitative evaluation value, and further optimizing and adjusting the litchi fresh-keeping control method. According to the method, litchis are pre-cooled and then stacked into a litchis stacked body, a low-frequency electric field is applied through a power supply device, and a capacitive electric field sensor array is used for monitoring and collecting original litchis fresh-keeping parameters in real time and pre-treating the original litchis fresh-keeping parameters to obtain the litchis fresh-keeping parameters; according to the method, the litchi preservation control electric field uniformity and the control reliability are quantitatively evaluated, the obtained electric field data uniformity quantized value and the obtained control reliability quantized value are compared with judgment values in a database for analysis, and therefore the method for optimizing the litchi preservation control is obtained, the reliability of the litchi preservation control method is improved, and the reliability of the litchi preservation control method is improved. The problem that in the prior art, a litchi preservation control method is insufficient in reliability is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of power supply control, and particularly to a litchi freshness preservation control method and system based on regulating low-frequency electric fields. Background Art

[0002] Due to insufficient freshness preservation technology, the export volume of fresh litchi fruits only accounts for 0.3% of the total output, causing an economic loss of approximately 4 billion yuan every year. Due to its perishable nature, litchi fruits are extremely prone to spoilage after harvesting, resulting in a loss rate of up to 18%-30% in the circulation link. Therefore, it is extremely urgent to improve the freshness preservation technology. With the high emphasis on the research and development of litchi freshness preservation technology, scientific research institutions have developed technologies such as pressure difference precooling and ultra-low temperature freezing and freshness locking, which not only extend the shelf life of litchi, but also promote the development of litchi deep processing products, enhance the export competitiveness and the income of fruit farmers, and effectively alleviate the problem of "increasing production without increasing income".

[0003] Existing litchi freshness preservation control methods use the electromagnetic field generated by wireless power transmission technology to process food through storage technology to extend its shelf life; use the electrostatic field generated by wireless power transmission technology to process food to reduce the growth of microorganisms and the activity of enzymes.

[0004] For example, the wireless power emission system and electrostatic wave freshness preservation device announced in the invention patent announcement with the publication number: CN109560620B includes: a wireless power emission device and a wireless power emission control circuit. The wireless power emission control circuit includes a power input terminal and an emission circuit. The emission circuit includes a control circuit and a coil drive circuit corresponding to driving each planar coil to work. After the control circuit respectively obtains the current intensity, current phase, and current frequency change of each planar coil, it determines the position of the receiving end according to the current intensity, current phase, and current frequency change of each planar coil, and outputs a control signal corresponding to each planar coil to the coil drive circuit corresponding to each planar coil. Each coil drive circuit respectively drives the corresponding coil so that the magnetic fields generated by each planar coil are superimposed into a magnetic field only for directional transmission to the receiving end.

[0005] However, in the process of implementing the technical solution of the invention in the embodiments of the present application, it is found that the above technologies have at least the following technical problems:

[0006] Due to the irregular shape and raised epidermis of litchi fruits, complex voids and tightly contacting areas are formed between the fruits during stacked preservation. When a low-frequency electric field is applied to the litchi stack, due to the irregular shape of the fruits and the stacking method, the electric field lines will be distorted, concentrated, and attenuated. The electric field attenuation causes the electric field intensity inside the litchi stack, especially in the central area, to be significantly lower than that on the surface. These areas cannot reach the expected preservation electric field intensity, thus affecting the preservation effect. The irregular shape of the litchi fruits and the stacking method lead to uneven distribution of the electric field inside the stack, especially severe attenuation of the internal electric field intensity, which cannot meet the preservation requirements, and there is a problem of insufficient reliability of the litchi preservation control method. Summary of the Invention

[0007] By providing a litchi preservation control method and system based on adjusting the low-frequency electric field, the embodiments of the present application solve the problem of insufficient reliability of the litchi preservation control method in the prior art and improve the reliability of the litchi preservation control method.

[0008] The embodiments of the present application provide a litchi preservation control method based on adjusting the low-frequency electric field, including the following steps: pre-cooling the litchi, stacking the pre-cooled litchi to form a litchi stack; applying a low-frequency electric field to the litchi stack through a power supply device, arranging a capacitive electric field sensor array in different areas of the litchi stack, real-time monitoring the electric field intensity in each area of the litchi stack, collecting the original litchi preservation parameters, and preprocessing the original litchi preservation parameters to obtain litchi preservation parameters; respectively quantitatively evaluating the uniformity of the litchi preservation control electric field and the reliability of the litchi preservation control through the litchi preservation parameters to obtain the quantization value of the electric field data uniformity and the quantization value of the control reliability; comparing and analyzing the quantization value of the electric field data uniformity and the quantization value of the control reliability with the first determination value of the quantization value of the electric field data uniformity and the second determination value of the quantization value of the control reliability in the litchi preservation control database respectively to obtain an optimized litchi preservation control method.

[0009] Further, the specific steps of forming the litchi stack are as follows: cooling the litchi through a refrigeration device, and at the same time using a thermometer to detect the central temperature of the litchi until the detected central temperature of the litchi drops to a predetermined temperature and then turning off the refrigeration device; applying a low-frequency electric field to the formed litchi stack through a power supply device, real-time monitoring the electric field intensity in each area of the litchi stack to obtain the original litchi preservation parameters, and the litchi stack is formed by prompting the staff to layer the pre-cooled litchi in a packaging container.

[0010] Furthermore, the litchi freshness preservation parameters are obtained by cleaning and removing outliers from the litchi freshness preservation original parameters; the litchi freshness preservation parameters include litchi freshness preservation parameter electric field data uniformity data and control reliability data; the electric field data uniformity data includes spatial electric field intensity, high-frequency pulse frequency, low-frequency electric field frequency, multi-physical field coupling period, and voltage ozone conversion efficiency; the control reliability data includes spatial electric field intensity, multi-physical field coupling period, ripple voltage peak value of the power supply output voltage, DC output voltage, electric field intensity measured in the central area of the litchi stack, and electric field intensity measured in the edge area of the litchi stack.

[0011] Furthermore, the litchi freshness preservation control electric field uniformity and litchi freshness preservation control reliability are respectively quantitatively evaluated through the litchi freshness preservation parameters, which also includes: obtaining the electric field data uniformity quantization value threshold, control reliability quantization value threshold, importance score of the electric field data uniformity quantization value, and importance score of the control reliability quantization value from the litchi freshness preservation control database; the electric field data uniformity quantization value threshold includes spatial electric field intensity threshold, high-frequency pulse frequency threshold, low-frequency electric field frequency standard value, multi-physical field coupling period standard value, and voltage ozone conversion efficiency threshold; the importance score of the electric field data uniformity quantization value includes importance score of spatial electric field intensity, importance score of high-frequency pulse frequency, importance score of low-frequency electric field frequency, importance score of multi-physical field coupling period, and importance score of voltage ozone conversion efficiency; the control reliability quantization value threshold includes the second spatial electric field intensity threshold and the second multi-physical field coupling period standard value; the importance score of the control reliability quantization value includes the second importance score of spatial electric field intensity, the second importance score of multi-physical field coupling period, importance score of the power supply ripple coefficient, and importance score of the electric field attenuation compensation coefficient.

[0012] Further, the specific steps to obtain the quantization value of the electric field data uniformity are as follows: perform a ratio analysis on the spatial electric field intensity and the spatial electric field intensity threshold, average the results of the ratio analysis, and correct the results of the averaging process using the importance score of the spatial electric field intensity to obtain the first component of the electric field data uniformity; perform a ratio analysis on the high-frequency pulse frequency and the high-frequency pulse frequency threshold, average the results of the ratio analysis, and correct the results of the averaging process using the importance score of the high-frequency pulse frequency, denoted as the second component of the electric field data uniformity; perform a ratio analysis on the deviation of the low-frequency electric field frequency from the low-frequency electric field frequency standard value and the low-frequency electric field frequency standard value, average the results of the ratio analysis, and correct the results of the averaging process using the importance score of the low-frequency electric field frequency, denoted as the third component of the electric field data uniformity; perform a ratio analysis on the deviation of the multi-physical field coupling period from the multi-physical field coupling period standard value and the multi-physical field coupling period standard value, and correct the results of the ratio analysis using the importance score of the multi-physical field coupling period, denoted as the fourth component of the electric field data uniformity; perform a ratio analysis on the voltage-ozone conversion efficiency and the voltage-ozone conversion efficiency threshold, average the results of the ratio analysis, and correct the results of the averaging process using the importance score of the voltage-ozone conversion efficiency, denoted as the fifth component of the electric field data uniformity; perform a coupling analysis on the first component of the electric field data uniformity, the second component of the electric field data uniformity, the third component of the electric field data uniformity, the fourth component of the electric field data uniformity, and the fifth component of the electric field data uniformity to obtain the quantization value of the electric field data uniformity; the quantization value of the electric field data uniformity represents the quantization data of the uniformity degree of the applied electric field in each region inside the litchi stack during the litchi preservation process.

[0013] Further, the specific analysis steps for quantifying the control reliability value are as follows: perform a ratio analysis of the second threshold of the spatial electric field intensity and the spatial electric field intensity, perform an averaging process on the result of the ratio analysis, and use the second importance score of the spatial electric field intensity to correct the result of the averaging process, denoted as the first component of the control reliability; perform a ratio analysis of the second standard value of the multi-physical field coupling period and the deviation between the multi-physical field coupling period and the standard value of the multi-physical field coupling period, and use the second importance score of the multi-physical field coupling period to correct the result of the ratio analysis, denoted as the second component of the control reliability; perform a ratio analysis of the peak value of the ripple voltage of the power supply output voltage and the DC output voltage to obtain the electric field attenuation compensation coefficient, perform an averaging process on the electric field attenuation compensation coefficient, and use the importance score of the electric field attenuation compensation coefficient to correct the result of the averaging process, denoted as the third component of the control reliability; perform a ratio analysis of the deviation between the electric field intensity measured in the central region of the litchi stack and the electric field intensity measured in the edge region of the litchi stack and the electric field intensity measured in the edge region of the litchi stack to obtain the power supply ripple coefficient, perform an averaging process on the power supply ripple coefficient, and use the importance score of the power supply ripple coefficient to correct the result of the averaging process, denoted as the fourth component of the control reliability; perform a ratio analysis of the coupling result of the first component, the second component, and the third component of the control reliability and the fourth component of the control reliability to obtain the control reliability quantification value; the control reliability quantification value represents the stability and reliability of the litchi freshness preservation control system.

[0014] Further, the specific steps for obtaining the optimized litchi freshness preservation control method are as follows: obtain the first determination value of the electric field data uniformity quantification value and the second determination value of the control reliability quantification value from the litchi freshness preservation control database; perform a comparative analysis of the electric field data uniformity quantification value and the control reliability quantification value with the first determination value of the electric field data uniformity quantification value and the second determination value of the control reliability quantification value respectively to obtain the optimized litchi freshness preservation control method; the optimized litchi freshness preservation control method includes the method for optimizing the electric field uniformity of litchi freshness preservation control and the method for optimizing the control reliability of litchi freshness preservation control.

[0015] Further, an optimized method for controlling the uniformity of the electric field for litchi preservation is as follows: If the quantization value of the electric field data uniformity is lower than or equal to the first determination value of the quantization value of the electric field data uniformity, the optimized method for controlling the uniformity of the electric field for litchi preservation is not triggered; if the quantization value of the electric field data uniformity is greater than the first determination value of the quantization value of the electric field data uniformity, the optimized method for controlling the uniformity of the electric field for litchi preservation is triggered. The optimized method for controlling the uniformity of the electric field for litchi preservation means identifying the tightly contacted areas where the electric field of the litchi stack is concentrated and the void areas where the electric field decays based on the monitored electric field intensity data, dynamically adjusting the spacing and angle of the multi-electrode array based on the quantization value of the electric field data uniformity, and optimizing the narrow pulse parameters by combining the cooperative modulation of the high-frequency pulse frequency and the low-frequency electric field frequency. The electric field intensity data is obtained by the capacitive electric field sensor array to monitor each area in the litchi stack in real time.

[0016] Further, an optimized method for controlling the reliability of litchi preservation is as follows: If the quantization value of the control reliability is greater than or equal to the second determination value of the quantization value of the control reliability, the optimized method for controlling the reliability of litchi preservation is not triggered; if the quantization value of the control reliability is lower than the second determination value of the quantization value of the control reliability, the optimized method for controlling the reliability of litchi preservation is triggered. The optimized method for controlling the reliability of litchi preservation means identifying the litchi stacking density based on the electric field intensity and the magnetic field intensity, and dynamically adjusting the electrode spacing, the high-frequency pulse parameters, and the alternating magnetic field frequency based on the quantization value of the control reliability to achieve the reliability control of litchi preservation under the synergistic action of multiple physical fields. The electric field intensity and the magnetic field intensity are obtained by the capacitive electric field sensor array and the magnetic sensor to monitor each area in the litchi stack in real time.

[0017] The embodiment of the present application provides a litchi preservation control system based on adjusting the low-frequency electric field, including a litchi precooling processing module, a litchi preservation parameter acquisition module, a litchi preservation parameter quantization evaluation module, and an optimized litchi preservation control method module: The litchi precooling processing module: is used to perform precooling treatment on litchis, stack the precooled litchis to form a litchi stack; The litchi preservation parameter acquisition module: is used to apply a low-frequency electric field to the litchi stack through a power supply device, arrange a capacitive electric field sensor array in different areas of the litchi stack, monitor the electric field intensity of each area in the litchi stack in real time, collect the original litchi preservation parameters, and perform preprocessing on the original litchi preservation parameters to obtain the litchi preservation parameters; The litchi preservation parameter quantization evaluation module: is used to perform quantization evaluation on the uniformity of the electric field for litchi preservation and the reliability of litchi preservation control respectively through the litchi preservation parameters, and obtain the quantization value of the electric field data uniformity and the quantization value of the control reliability; The optimized litchi preservation control method module: is used to compare and analyze the quantization value of the electric field data uniformity and the quantization value of the control reliability with the first determination value of the quantization value of the electric field data uniformity and the second determination value of the quantization value of the control reliability in the litchi preservation control database respectively to obtain the optimized litchi preservation control method.

[0018] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0019] 1. After pre-cooling litchis and stacking them into a litchi stack, a low-frequency electric field is applied by a power supply device, and a capacitive electric field sensor array is used to monitor and collect data in real time. The pre-cooling treatment can quickly reduce the temperature of litchis, slow down their metabolism and the growth of microorganisms, thereby extending the preservation period. Applying a low-frequency electric field can further inhibit the physiological activities of litchis, reduce nutrient consumption and water loss, and extend the preservation time. Furthermore, the electric field parameters can be adjusted in a timely manner to ensure the stability and reliability of the preservation effect.

[0020] 2. By using the original litchi preservation parameters and performing pre-treatment to obtain litchi preservation parameters, the uniformity and reliability of the electric field for litchi preservation control are quantitatively evaluated respectively. Through quantitative evaluation, areas with uneven electric field distribution or unreliable control systems can be identified and optimized specifically, which helps to improve the overall preservation effect and extend the preservation period of litchis.

[0021] 3. By comparing and analyzing the quantitative values of electric field data uniformity and control reliability with the determination values in the database respectively, a method for optimizing litchi preservation control is obtained. By optimizing the electric field uniformity and control reliability, the physiological activities of litchis and the growth of microorganisms can be inhibited, thereby extending the preservation period. A uniform electric field distribution can reduce litchi damage caused by local overheating or uneven treatment, thereby reducing the loss rate. Description of the Drawings

[0022] Figure 1 It is a flowchart of a litchi preservation control method based on adjusting a low-frequency electric field provided by the embodiments of the present application;

[0023] Figure 2 It is a structural diagram of a litchi preservation control system based on adjusting a low-frequency electric field provided by the embodiments of the present application;

[0024] Figure 3 It is a specific flowchart of a litchi preservation control method based on adjusting a low-frequency electric field provided by the embodiments of the present application. Detailed Embodiments

[0025] The embodiment of the present application provides a litchi fresh-keeping control method and system based on regulating low-frequency electric fields, which solves the problem of insufficient reliability of the litchi fresh-keeping control method in the prior art. After pre-cooling the litchis and stacking them into a litchi stack, a low-frequency electric field is applied by a power supply device, and a capacitive electric field sensor array is used to monitor and collect the original litchi fresh-keeping parameters in real time and preprocess them to obtain litchi fresh-keeping parameters. The uniformity and control reliability of the litchi fresh-keeping control electric field are quantitatively evaluated respectively, and the quantitative values of the electric field data uniformity and the control reliability are compared and analyzed with the determination values in the database respectively, so as to obtain a method for optimizing litchi fresh-keeping control and improve the reliability of the litchi fresh-keeping control method.

[0026] The technical solution in the embodiment of the present application is to solve the above problem of insufficient reliability of the litchi fresh-keeping control method. The general idea is as follows:

[0027] After pre-cooling the litchis and stacking them into a litchi stack, a low-frequency electric field is applied by a power supply device, and a capacitive electric field sensor array is used to monitor and collect the original litchi fresh-keeping parameters in real time and preprocess them to obtain litchi fresh-keeping parameters. The uniformity and control reliability of the litchi fresh-keeping control electric field are quantitatively evaluated respectively, and the quantitative values of the electric field data uniformity and the control reliability are compared and analyzed with the determination values in the database respectively, so as to obtain a method for optimizing litchi fresh-keeping control and improve the reliability of the litchi fresh-keeping control method.

[0028] In order to better understand the above technical solution, the above technical solution will be described in detail below in combination with the accompanying drawings of the specification and specific embodiments.

[0029] As Figure 1 shown, it is a flowchart of a litchi fresh-keeping control method based on regulating low-frequency electric fields provided by an embodiment of the present application. The method includes the following steps: pre-cooling the litchis, stacking the pre-cooled litchis to form a litchi stack; applying a low-frequency electric field to the litchi stack by a power supply device, arranging a capacitive electric field sensor array in different regions of the litchi stack, monitoring the electric field strength in each region of the litchi stack in real time, collecting the original litchi fresh-keeping parameters, and preprocessing the original litchi fresh-keeping parameters to obtain litchi fresh-keeping parameters; quantitatively evaluating the uniformity of the litchi fresh-keeping control electric field and the control reliability of the litchi fresh-keeping respectively by the litchi fresh-keeping parameters to obtain the quantitative value of the electric field data uniformity and the quantitative value of the control reliability; comparing and analyzing the quantitative value of the electric field data uniformity and the quantitative value of the control reliability with the first determination value of the electric field data uniformity quantitative value and the second determination value of the control reliability quantitative value in the litchi fresh-keeping control database respectively to obtain an optimized litchi fresh-keeping control method.

[0030] In this embodiment, the power supply device is a device that generates a low-frequency electric field, which can convert the input electrical energy into a low-frequency electric field output. The power supply device generally includes components such as a transformer, an oscillator, and an amplifier, and is used to generate and regulate the low-frequency electric field. The low-frequency electric field refers to an electric field with a relatively low frequency, usually between several tens of hertz and several kilohertz. Compared with the high-frequency electric field, the low-frequency electric field has a weaker penetration ability to organisms, but can affect the physiological processes of organisms. In litchi preservation, the low-frequency electric field can affect the physiological activities of litchis, thereby extending their preservation period. Applying the low-frequency electric field generated by the power supply device to the litchi stack can be achieved through the following steps: connecting the output end of the power supply device to the litchi stack through devices such as wires, electrodes, or electric field generators, and adjusting the power supply device to make the power supply device output the required low-frequency electric field, including setting parameters such as the frequency, intensity, and waveform of the electric field, starting the power supply device to make the low-frequency electric field act on the litchi stack. At this time, the litchis in the litchi stack will be affected by the low-frequency electric field. A capacitive electric field sensor array is arranged in different regions of the litchi stack, and these sensors can monitor the electric field intensity in each region of the litchi stack in real time, providing data support for subsequent preservation parameter collection.

[0031] Specifically, the specific steps to form the litchi stack are as follows: cooling the litchis through a refrigeration device, and at the same time using a thermometer to detect the central temperature of the litchis until the detected central temperature of the litchis drops to a predetermined temperature and then turning off the refrigeration device; applying a low-frequency electric field to the formed litchi stack through the power supply device, monitoring the electric field intensity in each region of the litchi stack in real time to obtain the original litchi preservation parameters. The litchi stack is formed by prompting the staff to place the pre-cooled litchis in layers in a packaging container.

[0032] In this embodiment, the refrigeration device is a device used to lower the temperature of an object. In the litchi preservation scenario, the role of the refrigeration device is to quickly lower the temperature of the litchis. The refrigeration device includes but is not limited to cold storages, chillers, etc. By using the refrigeration device to lower the temperature of the litchis, the respiration and microbial growth are inhibited, and the preservation period is extended. Using a thermometer to detect the central temperature of the litchis to ensure that the predetermined low temperature is reached. When the central temperature of the litchis reaches the predetermined temperature, turn off the refrigeration device, and use the low-frequency electric field to further inhibit the physiological activities of the litchis and extend the preservation period. Stack the pre-cooled litchis into a certain shape (litchi stack), and then apply a low-frequency electric field to it through the power supply device. A capacitive electric field sensor array is arranged in different regions of the litchi stack to monitor the electric field intensity in each region in real time. The staff, according to the prompt, place the pre-cooled litchis in layers in a packaging container. The packaging container includes but is not limited to plastic baskets, foam boxes, etc.

[0033] Specifically, the litchi fresh-keeping parameters are obtained by cleaning and removing outliers from the original litchi fresh-keeping parameters; the litchi fresh-keeping parameters include the electric field data uniformity data and control reliability data of the litchi fresh-keeping parameters; the electric field data uniformity data includes the spatial electric field intensity, high-frequency pulse frequency, low-frequency electric field frequency, multi-physical field coupling period, and voltage ozone conversion efficiency; the control reliability data includes the spatial electric field intensity, multi-physical field coupling period, ripple voltage peak value of the power supply output voltage, DC output voltage, electric field intensity measured in the central area of the litchi stack, and electric field intensity measured in the edge area of the litchi stack.

[0034] In this embodiment, data cleaning is used to repair errors and inconsistencies in the original litchi fresh-keeping data to ensure data integrity, accuracy, and consistency. Depending on the situation, options such as deleting missing records, filling with fixed values, identifying and deleting duplicate records through Isolation Forest, unifying data units, and converting data types are selected to ensure consistent data formats; identifying and handling outliers in the data to avoid interference with the analysis results, using statistical methods (such as the interquartile range method) to determine the range of normal values, finding records outside the normal value range, and deleting outliers by selecting records outside the normal value range. Alternatively, retention or correction can be selected according to the situation.

[0035] Specifically, the electric field uniformity of litchi fresh-keeping control and the control reliability of litchi fresh-keeping are quantitatively evaluated through the litchi fresh-keeping parameters. This also includes: obtaining the threshold value of the electric field data uniformity quantization value, the threshold value of the control reliability quantization value, the importance score of the electric field data uniformity quantization value, and the importance score of the control reliability quantization value from the litchi fresh-keeping control database; the threshold value of the electric field data uniformity quantization value includes the spatial electric field intensity threshold, high-frequency pulse frequency threshold, low-frequency electric field frequency standard value, multi-physical field coupling period standard value, and voltage ozone conversion efficiency threshold; the importance score of the electric field data uniformity quantization value includes the importance score of the spatial electric field intensity, the importance score of the high-frequency pulse frequency, the importance score of the low-frequency electric field frequency, the importance score of the multi-physical field coupling period, and the importance score of the voltage ozone conversion efficiency; the threshold value of the control reliability quantization value includes the second threshold value of the spatial electric field intensity and the second standard value of the multi-physical field coupling period; the importance score of the control reliability quantization value includes the second importance score of the spatial electric field intensity, the second importance score of the multi-physical field coupling period, the importance score of the power supply ripple coefficient, and the importance score of the electric field attenuation compensation coefficient.

[0036] Specifically, the specific steps to obtain the quantization value of the electric field data uniformity are as follows: perform a ratio analysis on the spatial electric field intensity and the spatial electric field intensity threshold, perform an averaging process on the results of the ratio analysis, use the importance score of the spatial electric field intensity to correct the results of the averaging process to obtain the first component of the electric field data uniformity; perform a ratio analysis on the high-frequency pulse frequency and the high-frequency pulse frequency threshold, perform an averaging process on the results of the ratio analysis, use the importance score of the high-frequency pulse frequency to correct the results of the averaging process, denoted as the second component of the electric field data uniformity; perform a ratio analysis on the deviation of the low-frequency electric field frequency from the low-frequency electric field frequency standard value and the low-frequency electric field frequency standard value, perform an averaging process on the results of the ratio analysis, use the importance score of the low-frequency electric field frequency to correct the results of the averaging process, denoted as the third component of the electric field data uniformity; perform a ratio analysis on the deviation of the multi-physical field coupling period from the multi-physical field coupling period standard value and the multi-physical field coupling period standard value, use the importance score of the multi-physical field coupling period to correct the results of the ratio analysis, denoted as the fourth component of the electric field data uniformity; perform a ratio analysis on the voltage-ozone conversion efficiency and the voltage-ozone conversion efficiency threshold, perform an averaging process on the results of the ratio analysis, use the importance score of the voltage-ozone conversion efficiency to correct the results of the averaging process, denoted as the fifth component of the electric field data uniformity; perform a coupling analysis on the first component, the second component, the third component, the fourth component, and the fifth component of the electric field data uniformity to obtain the quantization value of the electric field data uniformity; the quantization value of the electric field data uniformity represents the quantization data of the uniformity degree of the applied electric field in each region inside the litchi stack during the litchi fresh-keeping process.

[0037] In this embodiment, the specific method for analyzing and obtaining the quantization value of the litchi fresh-keeping control electric field uniformity is as follows:

[0038]

[0039] ρ1 + ρ2 + ρ3 + ρ4 + ρ5 = 1;

[0040] Number the preset litchi fresh-keeping control electric field uniformity detection points in sequence. N0 represents the number of the litchi fresh-keeping control electric field uniformity detection point under the T0-th litchi fresh-keeping control electric field uniformity detection segment, N0 = 1, 2,..., N, and N represents the total number of the litchi fresh-keeping control electric field uniformity detection point numbers.

[0041] Divide the preset litchi fresh-keeping control electric field uniformity time into litchi fresh-keeping control electric field uniformity detection segments with the same time length. T0 represents the number of the litchi fresh-keeping control electric field uniformity detection segment, T0 = 1, 2,..., T, and T represents the total number of the litchi fresh-keeping control electric field uniformity detection segment numbers.

[0042] Represents the quantification value of the uniformity of the litchi fresh-keeping control electric field for the T0th litchi fresh-keeping control electric field uniformity detection segment.

[0043] Represents the spatial electric field intensity at the N0th litchi fresh-keeping control electric field uniformity detection point, which is the electric field intensity generated by the low-frequency electric field applied by the power supply device to the litchi stack.

[0044] K0 represents the spatial electric field intensity threshold, which is a preset spatial electric field intensity threshold obtained from the litchi fresh-keeping control database and can be the average value of the spatial electric field intensities at the historical litchi fresh-keeping control electric field uniformity detection points in the litchi fresh-keeping control database.

[0045] Represents the high-frequency pulse frequency at the N0th litchi fresh-keeping control electric field uniformity detection point.

[0046] G0 represents the high-frequency pulse frequency threshold, which is a preset high-frequency pulse frequency threshold obtained from the litchi fresh-keeping control database and can be the average value of the high-frequency pulse frequencies at the historical litchi fresh-keeping control electric field uniformity detection points in the litchi fresh-keeping control database.

[0047] Represents the low-frequency electric field frequency at the N0th litchi fresh-keeping control electric field uniformity detection point.

[0048] D0 represents the standard value of the low-frequency electric field frequency, which is a preset standard value of the low-frequency electric field frequency obtained from the litchi fresh-keeping control database and can be the average value of the low-frequency electric field frequencies at the historical litchi fresh-keeping control electric field uniformity detection points in the litchi fresh-keeping control database.

[0049] Represents the multi-physical field coupling period for the T0th litchi fresh-keeping control electric field uniformity detection segment, which refers to the time period of the alternating action of high-frequency pulses and low-frequency electric fields.

[0050] Z0 represents the standard value of the multi-physical field coupling period, which is a preset standard value of the multi-physical field coupling period obtained from the litchi fresh-keeping control database and can be the average value of the multi-physical field coupling periods at the historical litchi fresh-keeping control electric field uniformity detection segments in the litchi fresh-keeping control database.

[0051] Represents the voltage-ozone conversion efficiency at the N0th litchi fresh-keeping control electric field uniformity detection point, which refers to the ratio between the output voltage of the electrostatic wave generator and the amount of ozone generated.

[0052] H0 represents the voltage ozone conversion efficiency threshold, which is a preset voltage ozone conversion efficiency threshold obtained from the litchi fresh-keeping control database. It can be the average value of the voltage ozone conversion efficiency at the historical litchi fresh-keeping control electric field uniformity detection points in the litchi fresh-keeping control database.

[0053] ρ1 is the preset spatial electric field intensity importance score obtained from the litchi fresh-keeping control database.

[0054] ρ2 is the preset high-frequency pulse frequency importance score obtained from the litchi fresh-keeping control database.

[0055] ρ3 is the preset low-frequency electric field frequency importance score obtained from the litchi fresh-keeping control database.

[0056] ρ4 is the preset multi-physical field coupling period importance score obtained from the litchi fresh-keeping control database.

[0057] ρ5 is the preset voltage ozone conversion efficiency importance score obtained from the litchi fresh-keeping control database.

[0058] Obtain the mapping table of importance scores through the database. For example, quickly extract the corresponding importance scores according to the currently received spatial electric field intensity, high-frequency pulse frequency, low-frequency electric field frequency, multi-physical field coupling period, and voltage ozone conversion efficiency, such as the importance score of spatial electric field intensity, the importance score of high-frequency pulse frequency, the importance score of low-frequency electric field frequency, the importance score of multi-physical field coupling period, and the importance score of voltage ozone conversion efficiency. This mapping table defines a clear set of association rules that convert the specific values of the received spatial electric field intensity, high-frequency pulse frequency, low-frequency electric field frequency, multi-physical field coupling period, and voltage ozone conversion efficiency into their corresponding importance scores. Under this mechanism, whether it is to achieve a one-to-one exact match or a many-to-one relationship where multiple parameters converge into a single weight, the dynamic acquisition of importance scores can be effectively achieved.

[0059] The higher the high-frequency pulse frequency, the more times the direction of the electric field changes per unit time, enhancing the killing effect on microorganisms. A higher spatial electric field intensity is required to ensure the effect, so the spatial electric field intensity is higher; the spatial electric field intensity and the low-frequency electric field frequency act together. The low-frequency electric field frequency determines the slow period of the electric field change, while the spatial electric field intensity determines the magnitude of the electric field force. The two need to be matched to achieve the best fresh-keeping effect; within the multi-physical field coupling period, the high-frequency pulse and the low-frequency electric field act alternately, and the spatial electric field intensity needs to be adjusted according to different action stages to achieve the best synergistic effect; the voltage ozone conversion efficiency determines the ozone production per unit voltage, and the concentration distribution of ozone will be affected by the spatial electric field intensity. The higher the spatial electric field intensity, the more conducive to the uniform distribution of ozone, thereby improving the fresh-keeping effect.

[0060] There is a positive correlation between the spatial electric field intensity and the quantization value of the electric field uniformity for litchi fresh-keeping control. The higher the spatial electric field intensity, the more local electric field concentration occurs, and the larger the quantization value of the electric field uniformity for litchi fresh-keeping control. There is a positive correlation between the high-frequency pulse frequency and the quantization value of the electric field uniformity for litchi fresh-keeping control. The higher the high-frequency pulse frequency, the more the propagation characteristics of the electric field in the medium change, resulting in the skin effect, and the larger the quantization value of the electric field uniformity for litchi fresh-keeping control. There is a positive correlation between the absolute value of the difference between the low-frequency electric field frequency and the low-frequency electric field frequency standard value and the quantization value of the electric field uniformity for litchi fresh-keeping control. The higher the absolute value of the difference between the low-frequency electric field frequency and the low-frequency electric field frequency standard value, the slower the electric field changes, which is not sufficient to effectively inhibit the growth of microorganisms, and the larger the quantization value of the electric field uniformity for litchi fresh-keeping control. There is a positive correlation between the absolute value of the difference between the multi-physical field coupling period and the multi-physical field coupling period standard value and the quantization value of the electric field uniformity for litchi fresh-keeping control. The higher the absolute value of the difference between the multi-physical field coupling period and the multi-physical field coupling period standard value, the more uneven distribution occurs during the alternation of the electric field, and the larger the quantization value of the electric field uniformity for litchi fresh-keeping control. There is a positive correlation between the voltage-ozone conversion efficiency and the quantization value of the electric field uniformity for litchi fresh-keeping control. The higher the voltage-ozone conversion efficiency, the greater the influence of the electric field by ozone in some regions and the smaller in other regions, and the larger the quantization value of the electric field uniformity for litchi fresh-keeping control.

[0061] Furthermore, the specific analysis steps for the control reliability quantization value are as follows: Conduct a ratio analysis of the second threshold of the spatial electric field intensity and the spatial electric field intensity, perform an averaging process on the results of the ratio analysis, and correct the results of the averaging process using the second importance score of the spatial electric field intensity, denoted as the first component of control reliability; Conduct a ratio analysis of the second standard value of the multi-physical field coupling period and the deviation between the multi-physical field coupling period and the multi-physical field coupling period standard value, and correct the results of the ratio analysis using the second importance score of the multi-physical field coupling period, denoted as the second component of control reliability; Conduct a ratio analysis of the peak value of the ripple voltage of the power supply output voltage and the DC output voltage to obtain the electric field attenuation compensation coefficient, perform an averaging process on the electric field attenuation compensation coefficient, and correct the results of the averaging process using the importance score of the electric field attenuation compensation coefficient, denoted as the third component of control reliability; Conduct a ratio analysis of the deviation between the electric field intensity measured in the central region of the litchi stack and the electric field intensity measured in the edge region of the litchi stack and the electric field intensity measured in the edge region of the litchi stack to obtain the power supply ripple coefficient, perform an averaging process on the power supply ripple coefficient, and correct the results of the averaging process using the importance score of the power supply ripple coefficient, denoted as the fourth component of control reliability; Conduct a ratio analysis of the coupling result of the first component of control reliability, the second component of control reliability, and the third component of control reliability and the fourth component of control reliability to obtain the control reliability quantization value; The control reliability quantization value represents the stability and reliability of the litchi fresh-keeping control system.

[0062] In this embodiment, the specific method for analyzing and obtaining the quantization value of litchi freshness preservation control reliability is as follows:

[0063]

[0064] Number the preset litchi freshness preservation control reliability detection points in sequence. S0 represents the number of the litchi freshness preservation control reliability detection point under the L0th litchi freshness preservation control reliability detection segment, S0 = 1, 2,..., S, and S represents the total number of litchi freshness preservation control reliability detection point numbers.

[0065] Divide the preset litchi freshness preservation control reliability time into litchi freshness preservation control reliability detection segments of the same time length. L0 represents the number of the litchi freshness preservation control reliability detection segment, L0 = 1, 2,..., L, and L represents the total number of litchi freshness preservation control reliability detection segment numbers.

[0066] represents the quantization value of litchi freshness preservation control reliability of the L0th litchi freshness preservation control reliability detection segment.

[0067] represents the space electric field intensity under the S0th litchi freshness preservation control reliability detection point.

[0068] B0 represents the second threshold of the space electric field intensity, which is a preset second threshold of the space electric field intensity obtained from the litchi freshness preservation control database, and can be the average value of the space electric field intensity under the historical litchi freshness preservation control reliability detection points in the litchi freshness preservation control database.

[0069] Q0 represents the second standard value of the multi-physical-field coupling period, which is a preset second standard value of the multi-physical-field coupling period obtained from the litchi freshness preservation control database, and can be the average value of the multi-physical-field coupling periods under the historical litchi freshness preservation control reliability detection segments in the litchi freshness preservation control database.

[0070] represents the multi-physical-field coupling period under the L0th litchi freshness preservation control reliability detection segment.

[0071] represents the power supply ripple coefficient under the S0th litchi freshness preservation control reliability detection point.

[0072] represents the electric field attenuation compensation coefficient under the S0th litchi freshness preservation control reliability detection point. Measure the electric field intensity at different positions inside the litchi stack, especially at the center and edge positions, using an electric field intensity meter or a high-voltage probe.

[0073] Represents the peak ripple voltage of the power output voltage at the S0th litchi freshness preservation control reliability detection point, measured using an oscilloscope or a voltmeter.

[0074] Represents the DC output voltage at the S0th litchi freshness preservation control reliability detection point.

[0075] Represents the electric field strength measured in the central area of the litchi stack at the S0th litchi freshness preservation control reliability detection point.

[0076] Represents the electric field strength measured in the edge area of the litchi stack at the S0th litchi freshness preservation control reliability detection point.

[0077] Is the second importance score of the preset space electric field strength obtained from the litchi freshness preservation control database.

[0078] Is the second importance score of the preset multi-physical field coupling period obtained from the litchi freshness preservation control database.

[0079] Is the importance score of the preset power supply ripple coefficient obtained from the litchi freshness preservation control database.

[0080] Is the importance score of the preset electric field attenuation compensation coefficient obtained from the litchi freshness preservation control database.

[0081] Obtain a mapping table of importance scores through the database. For example, quickly extract the corresponding importance scores according to the current space electric field strength, multi-physical field coupling period, power supply ripple coefficient, and electric field attenuation compensation coefficient, such as the importance score of the space electric field strength, the importance score of the multi-physical field coupling period, the importance score of the power supply ripple coefficient, and the importance score of the electric field attenuation compensation coefficient. This mapping table defines a clear set of association rules, which converts the specific values of the space electric field strength, multi-physical field coupling period, power supply ripple coefficient, and electric field attenuation compensation coefficient into their corresponding importance scores. Under this mechanism, whether it is to achieve an exact one-to-one match or a one-to-many relationship where multiple parameters converge into a single weight, the dynamic acquisition of importance scores can be effectively realized.

[0082] The power supply ripple coefficient affects the stability of the output voltage, which in turn affects the uniformity and stability of the spatial electric field intensity. The larger the power supply ripple coefficient, the greater the fluctuation of the electric field intensity. The magnitude and distribution of the electric field intensity affect the dynamic process of multi-physical field coupling, thus affecting the coupling period. The higher the spatial electric field intensity, the longer the multi-physical field coupling period. The electric field attenuation compensation coefficient is used to describe and compensate for the attenuation differences of the electric field at different positions (especially the center and the edge) inside the litchi stack. The electric field attenuation compensation coefficient is based on the measurement of the spatial electric field intensity and is used to ensure the uniformity of the electric field inside the stack.

[0083] There is a negative correlation between the spatial electric field intensity and the quantified value of the reliability of litchi freshness preservation control. The higher the spatial electric field intensity, the more likely it is to cause tissue damage to the litchi and reduce the freshness preservation effect, and the smaller the quantified value of the reliability of litchi freshness preservation control. There is a negative correlation between the multi-physical field coupling period and the quantified value of the reliability of litchi freshness preservation control, which leads to unstable freshness preservation effect and the smaller the quantified value of the reliability of litchi freshness preservation control. There is a negative correlation between the power supply ripple coefficient and the quantified value of the reliability of litchi freshness preservation control. The larger the power supply ripple coefficient, the worse the stability of the power supply output, which leads to fluctuations in the electric field intensity and the smaller the quantified value of the reliability of litchi freshness preservation control. There is a positive correlation between the electric field attenuation compensation coefficient and the quantified value of the reliability of litchi freshness preservation control. The higher the electric field attenuation compensation coefficient, the more uniform the distribution of the electric field inside the litchi stack, the better the freshness preservation effect, and the larger the quantified value of the reliability of litchi freshness preservation control.

[0084] Furthermore, the specific steps to obtain the optimized litchi freshness preservation control method are as follows: Obtain the first determination value of the quantified value of the electric field data uniformity and the second determination value of the quantified value of the control reliability from the litchi freshness preservation control database; Compare and analyze the quantified value of the electric field data uniformity and the quantified value of the control reliability with the first determination value of the quantified value of the electric field data uniformity and the second determination value of the quantified value of the control reliability respectively to obtain the optimized litchi freshness preservation control method. The optimized litchi freshness preservation control method includes the method for optimizing the uniformity of the litchi freshness preservation control electric field and the method for optimizing the reliability of the litchi freshness preservation control.

[0085] Specifically, the method for optimizing the uniformity of the litchi freshness preservation control electric field is as follows: If the quantified value of the electric field data uniformity is lower than or equal to the first determination value of the quantified value of the electric field data uniformity, the method for optimizing the uniformity of the litchi freshness preservation control electric field is not triggered; If the quantified value of the electric field data uniformity is greater than the first determination value of the quantified value of the electric field data uniformity, the method for optimizing the uniformity of the litchi freshness preservation control electric field is triggered. The method for optimizing the uniformity of the litchi freshness preservation control electric field means identifying the tightly contacted areas with concentrated electric fields and the void areas with electric field attenuation in the litchi stack based on the monitored electric field intensity data, dynamically adjusting the spacing and angle of the multi-electrode array according to the quantified value of the electric field data uniformity, and optimizing the narrow pulse parameters by combining the coordinated modulation of the high-frequency pulse frequency and the low-frequency electric field frequency. The electric field intensity data is obtained by real-time monitoring of each area inside the litchi stack through a capacitive electric field sensor array.

[0086] In this embodiment, a capacitive electric field sensor array is used to monitor the electric field intensity in each region of the litchi stack in real time. According to the sensor data, interpolation algorithms (such as Kriging interpolation, inverse distance weighted interpolation, etc.) are used to interpolate the collected data to generate a continuous three-dimensional electric field distribution model. A three-dimensional coordinate system is constructed, and the electric field intensity values are mapped to the corresponding spatial positions. A color mapping scheme (such as rainbow color, hot metal color, etc.) is selected to map the electric field intensity values to different colors. Three-dimensional graphics rendering technology (such as OpenGL, DirectX, etc.) is used to draw a three-dimensional electric field distribution heat map. The uniformity quantization value of the electric field data is calculated to evaluate the uniformity of the electric field distribution. A lower uniformity quantization value of the electric field data indicates a more uniform electric field distribution; otherwise, it indicates the existence of uneven regions with too high or too low electric field intensity. After identifying the regions with severe electric field intensity attenuation, the spacing and angle of the multi-electrode array are dynamically adjusted. Two levels of thresholds are set, and the secondary threshold is greater than the primary threshold. The primary threshold and the secondary threshold are preset primary and secondary thresholds obtained from the litchi freshness preservation control database. For the tightly contacting regions with concentrated electric fields: the electrode spacing is increased by an electric means (electric push rod) to avoid excessive electric field intensity. The electrode spacing is greater than the primary threshold and less than the secondary threshold. The tightly contacting regions cause the electric field lines to be overly concentrated, resulting in too high local electric field intensity, damaging the litchi epidermis or causing electric breakdown. By increasing the electrode spacing, the electric field lines can be dispersed and the local electric field intensity can be reduced. For the void regions with attenuated electric fields: the electrode spacing is reduced or the electrode density is increased by an electric means (electric push rod) to enhance the electric field intensity. The electrode spacing is less than the primary threshold and the electrode spacing is greater than the reference threshold. The reference threshold is the standard distance of the electrode spacing. Due to the lack of a medium in the void regions, the electric field lines are difficult to penetrate, resulting in attenuated electric field intensity. By reducing the electrode spacing or increasing the electrode density, the electric field intensity can be enhanced to ensure that the litchis in the void regions can also be effectively preserved.Utilize intermittent high-frequency pulses through narrow pulse modulation to improve the sterilization efficiency while reducing energy consumption. The high-frequency high-voltage electric field generated by the narrow pulses can quickly activate the low-temperature plasma, generating strongly oxidizing substances such as ozone and reactive oxygen species to achieve the instantaneous killing of microorganisms (such as Penicillium) on the surface of lychees. Through the design of an extremely narrow pulse width and a low duty cycle, the energy loss of the equipment is significantly reduced. The short pulses penetrate the gaps in the lychee epidermis for sterilization, avoiding the continuous damage to the lychee epidermal cells and pulp cells caused by long-term high voltage, and helping to maintain the hardness and juice retention rate of the pulp; set the pulse width to be greater than the first pulse width threshold and less than the second pulse width threshold. The first pulse width threshold and the second pulse width threshold are preset first pulse width threshold and second pulse width threshold obtained from the lychee preservation control database. The extremely narrow pulse width can reduce energy loss and avoid damage to the lychee epidermal cells caused by long-term high voltage; set the pulse frequency to be greater than the first pulse frequency threshold and less than the second pulse frequency threshold. The first pulse frequency threshold and the second pulse frequency threshold are preset first pulse frequency threshold and second pulse frequency threshold obtained from the lychee preservation control database. The high-frequency pulses can quickly activate the low-temperature plasma (including ozone and reactive oxygen species) to achieve the instantaneous killing of surface microorganisms (such as Penicillium). Through the low-duty-cycle design, control the rated power of the electrostatic wave generator within the preset threshold. Use a high-voltage ceramic capacitor and a pulse transformer to boost the input voltage to the target range. The target range is that the input voltage is greater than the first input voltage threshold and the input voltage is less than the second input voltage threshold. The first input voltage threshold and the second input voltage threshold are preset first input voltage threshold and second input voltage threshold obtained from the lychee preservation control database. If the power supply ripple coefficient is less than the preset threshold, suppress the voltage fluctuation caused by pulse switching through an integrated digital filter circuit to ensure the stability of the electric field, and ensure the long-term stable operation of the electrostatic wave generator for the voltage fluctuations (such as the start and stop of the cold storage compressor) during cold chain transportation. When the current is greater than the preset current threshold, the fuse cuts off the circuit with a millisecond-level delay to avoid damage to the equipment due to transient overload. The instantaneous high voltage of the narrow pulse releases energy only within the microsecond level, significantly reducing the equipment heating. The high-frequency pulses (such as 1 kHz) can quickly ionize the air to generate a high concentration of ozone (the electrostatic wave / ozone ratio is greater than or equal to the preset threshold), replacing traditional chemical fungicides. The short pulses can penetrate the gaps in the lychee epidermis for sterilization but will not continuously damage the pulp cell membrane, maintaining the pulp hardness and juice retention rate. After narrow pulse pretreatment, switch to a low-frequency electric field to maintain the spatial electric field strength greater than or equal to the preset threshold to inhibit enzyme activity and water migration, which is used to improve the uniform distribution of the electric field during the lychee preservation process.

[0087] Further, the method for optimizing the reliability of litchi fresh-keeping control is as follows: if the quantization value of control reliability is greater than or equal to the second determination value of the quantization value of control reliability, the method for optimizing the reliability of litchi fresh-keeping control is not triggered; if the quantization value of control reliability is lower than the second determination value of the quantization value of control reliability, the method for optimizing the reliability of litchi fresh-keeping control is triggered. The method for optimizing the reliability of litchi fresh-keeping control means identifying the litchi stacking density according to the electric field strength and magnetic field strength, and dynamically adjusting the electrode spacing, high-frequency pulse parameters and alternating magnetic field frequency based on the quantization value of control reliability to achieve the reliability control of litchi fresh-keeping under the synergistic action of multiple physical fields. The electric field strength and magnetic field strength are obtained by real-time monitoring of each area in the litchi stacking body through a capacitive electric field sensor array and a magnetic field sensor.

[0088] In this embodiment, through magnetic field coupling optimization, a periodic magnetic field is coordinated with narrow pulses to polarize water molecules and delay ice crystal formation, reducing the loss of free water. The periodic magnetic field affects the movement of water molecules through the Lorentz force, making them tend to be arranged in an orderly manner, thereby polarizing the water molecules. Polarized water molecules are more difficult to form ice crystals in a low-temperature environment because the formation of ice crystals requires water molecules to aggregate in a specific way, and the polarization effect disrupts this tendency to aggregate. The high-frequency and high-voltage electric field generated by the narrow pulses can quickly activate the low-temperature plasma to generate strongly oxidizing substances such as ozone and reactive oxygen species, achieving instantaneous killing of microorganisms on the surface of lychees. At the same time, the instantaneous high voltage of the narrow pulses can release energy within microseconds, significantly reducing equipment heating and energy consumption. The combined action of the periodic magnetic field and the narrow pulses can further enhance the polarization effect of water molecules. The instantaneous high voltage of the narrow pulses can instantaneously change the electric field distribution, making it easier for water molecules to be polarized under the combined action of the electric field and the magnetic field. The increased difficulty of polarized water molecules forming ice crystals in a low-temperature environment delays the formation of ice crystals and reduces the loss of free water. To meet the fresh-keeping requirements of lychees with different stacking densities, the modular equipment is designed with a dynamic working mode switching function, setting two levels of thresholds, with the secondary threshold being greater than the primary threshold. In the case of a loose stacking scenario, the electrode spacing is increased by an electric means (electric push rod) to avoid excessive electric field intensity. The electrode spacing is greater than the primary threshold and less than the secondary threshold, ensuring that in the case of loose stacking, the electric field can be evenly distributed and cover each lychee. A low-frequency electric field (the low-frequency electric field is greater than the primary low-frequency electric field threshold and less than the secondary low-frequency electric field threshold, and the primary low-frequency electric field threshold and the secondary low-frequency electric field threshold are preset primary low-frequency electric field thresholds and secondary low-frequency electric field thresholds obtained from the lychee fresh-keeping control database) is used for maintenance to maintain a stable electric field environment. The magnetic field scanning frequency is set to once within the preset threshold to monitor and adjust the magnetic field intensity to ensure its polarization effect on water molecules. In the case of a tight stacking scenario (high stacking density), the electrode spacing is reduced or the electrode density is increased by an electric means (electric push rod) to enhance the electric field intensity. The electrode spacing is less than the primary threshold and greater than the reference threshold. Such a configuration can ensure that in the case of tight stacking, the electric field intensity in the central area can still meet the requirements. High-frequency pulses are used for pretreatment to quickly kill microorganisms, and then switched to a low-frequency electric field for maintenance. The magnetic field scanning frequency is increased to more frequently monitor and adjust the magnetic field intensity. The supercapacitor buffer energy storage technology is used to reduce the electric field fluctuations caused by intermittent power supply and ensure the stable output of the electric field intensity, improving the fresh-keeping effect. In summary, the reliability quantification value of the control method is reflected in the stability and reliability of the control system during the lychee fresh-keeping process by dynamically adjusting the electrode spacing, high-frequency pulse parameters, and alternating magnetic field frequency, as well as modular equipment design, supercapacitor buffer energy storage technology, feedback control, and multiple safety protection measures.

[0089] As Figure 2As shown in the figure, it is the structural diagram of the litchi fresh-keeping control system based on regulating low-frequency electric field provided by the embodiment of the present application. The litchi fresh-keeping control system based on regulating low-frequency electric field provided by the embodiment of the present application includes: a litchi precooling treatment module, a litchi fresh-keeping parameter acquisition module, a litchi fresh-keeping parameter quantification and evaluation module, and an optimized litchi fresh-keeping control method module: The litchi precooling treatment module: is used to perform precooling treatment on litchi, and stack the precooled litchi to form a litchi stack; The litchi fresh-keeping parameter acquisition module: is used to apply a low-frequency electric field to the litchi stack through a power supply device, arrange a capacitive electric field sensor array in different regions of the litchi stack, monitor the electric field intensity in each region of the litchi stack in real time, acquire the original litchi fresh-keeping parameters, and perform preprocessing on the original litchi fresh-keeping parameters to obtain litchi fresh-keeping parameters; The litchi fresh-keeping parameter quantification and evaluation module: is used to respectively perform quantitative evaluation on the uniformity of the litchi fresh-keeping control electric field and the reliability of the litchi fresh-keeping control through the litchi fresh-keeping parameters, and obtain the quantitative value of the electric field data uniformity and the quantitative value of the control reliability; The optimized litchi fresh-keeping control method module: is used to respectively compare and analyze the quantitative value of the electric field data uniformity and the quantitative value of the control reliability with the first determination value of the electric field data uniformity quantitative value and the second determination value of the control reliability quantitative value in the litchi fresh-keeping control database to obtain an optimized litchi fresh-keeping control method.

[0090] As Figure 3 shown in the figure, it is the specific flowchart of the litchi fresh-keeping control method based on regulating low-frequency electric field provided by the embodiment of the present application, including: performing precooling treatment on litchi and stacking it into a litchi stack, applying a low-frequency electric field to it through a power supply device, and using a capacitive electric field sensor array to monitor the electric field intensity in each region in real time, acquiring the original litchi fresh-keeping parameters and performing preprocessing to obtain litchi fresh-keeping parameters, performing quantitative evaluation on the uniformity and reliability of the litchi fresh-keeping control electric field through the litchi fresh-keeping parameters to obtain the quantitative value of the electric field data uniformity and the quantitative value of the control reliability, and comparing and analyzing them with the determination values in the database to optimize the litchi fresh-keeping control method. The optimized litchi fresh-keeping control method includes: dynamically adjusting the electrode spacing and angle according to the three-dimensional electric field distribution heat map, increasing the electrode spacing for the closely contacted region, reducing the electrode spacing or increasing the electrode density for the void region to improve the electric field uniformity; adopting a narrow pulse modulation technique, setting two levels of preset threshold values to control the pulse width and frequency, and using a high-voltage ceramic capacitor, a pulse transformer, a digital filter circuit, etc. to ensure the electric field stability, reduce energy consumption, and improve the sterilization efficiency; coordinating the periodic magnetic field with the narrow pulse to polarize water molecules, delay the formation of ice crystals, reduce the loss of free water, and dynamically adjust the magnetic field scanning frequency according to the stacking density; the modular equipment design has a dynamic working mode switching function and a supercapacitor buffer energy storage technology to adapt to different stacking densities and reduce the electric field fluctuation, improving the fresh-keeping effect.

[0091] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) that contain computer-usable program code.

[0092] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be realized by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices produce means for realizing the functions specified in Figure 1 one or more of the flows Figure 1 or blocks or the combination of blocks.

[0093] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing devices to work in a specific manner, such that the instructions stored in the computer-readable memory produce a manufactured article including instruction means that realizes the functions specified in Figure 1 one or more of the flows Figure 1 or blocks or the combination of blocks.

[0094] These computer program instructions can also be loaded onto a computer or other programmable data processing devices, such that a series of operation steps are executed on the computer or other programmable devices to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable devices provide steps for realizing the functions specified in Figure 1 one or more of the flows Figure 1 or blocks or the combination of blocks.

[0095] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concepts. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications that fall within the scope of the present invention.

[0096] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A litchi fresh-keeping control method based on adjusting low-frequency electric fields, characterized in that It includes the following steps: Perform pre-cooling treatment on lychees, stack the pre-cooled lychees to form a lychee stack; Apply a low-frequency electric field to the lychee stack through a power supply device, arrange a capacitive electric field sensor array in different regions of the lychee stack, monitor the electric field strength in each region of the lychee stack in real time, collect the original lychee preservation parameters, and preprocess the original lychee preservation parameters to obtain lychee preservation parameters; Quantitatively evaluate the uniformity of the lychee preservation control electric field and the reliability of the lychee preservation control respectively through the lychee preservation parameters to obtain the quantization value of the electric field data uniformity and the quantization value of the control reliability; Compare and analyze the quantization value of the electric field data uniformity and the quantization value of the control reliability with the first determination value of the quantization value of the electric field data uniformity and the second determination value of the quantization value of the control reliability in the lychee preservation control database respectively to obtain an optimized lychee preservation control method.

2. The litchi fresh-keeping control method based on regulating low-frequency electric field according to claim 1, wherein The specific steps for forming the lychee stack are as follows: Cool the lychees through a refrigeration device, and at the same time use a thermometer to detect the central temperature of the lychees until the detected central temperature of the lychees drops to a predetermined temperature and then turn off the refrigeration device; Apply a low-frequency electric field to the formed lychee stack through a power supply device, monitor the electric field strength in each region of the lychee stack in real time to obtain the original lychee preservation parameters, and the lychee stack is formed by prompting the staff to place the pre-cooled lychees in layers in a packaging container.

3. The litchi fresh-keeping control method based on regulating low-frequency electric field according to claim 1, wherein, The lychee preservation parameters are obtained by cleaning and removing outliers from the original lychee preservation parameters; The lychee preservation parameters include the electric field data uniformity data and the control reliability data of the lychee preservation parameters; The electric field data uniformity data includes the spatial electric field strength, high-frequency pulse frequency, low-frequency electric field frequency, multi-physical field coupling period, and voltage ozone conversion efficiency; The control reliability data includes the spatial electric field strength, multi-physical field coupling period, ripple voltage peak value of the power supply output voltage, DC output voltage, electric field strength measured in the central region of the lychee stack, and electric field strength measured in the edge region of the lychee stack.

4. The litchi fresh-keeping control method based on regulating low-frequency electric field according to claim 3, characterized in that, Before quantitatively evaluating the uniformity of the lychee preservation control electric field and the reliability of the lychee preservation control respectively through the lychee preservation parameters, it also includes: Obtain the threshold value of the quantization value of the electric field data uniformity, the threshold value of the quantization value of the control reliability, the importance score of the quantization value of the electric field data uniformity, and the importance score of the quantization value of the control reliability from the lychee preservation control database; The threshold value of the quantization value of the electric field data uniformity includes the spatial electric field strength threshold, high-frequency pulse frequency threshold, standard value of the low-frequency electric field frequency, standard value of the multi-physical field coupling period, and voltage ozone conversion efficiency threshold; The importance score of the quantization value of the electric field data uniformity includes the importance score of the spatial electric field strength, the importance score of the high-frequency pulse frequency, the importance score of the low-frequency electric field frequency, the importance score of the multi-physical field coupling period, and the importance score of the voltage ozone conversion efficiency; The threshold value of the quantization value of the control reliability includes the second threshold value of the spatial electric field strength and the second standard value of the multi-physical field coupling period; The importance scores of the control reliability quantization value include the second importance score of the spatial electric field intensity, the second importance score of the multi-physical field coupling period, the importance score of the power supply ripple coefficient, and the importance score of the electric field attenuation compensation coefficient.

5. The litchi fresh-keeping control method based on regulating low-frequency electric field according to claim 4, wherein, The specific steps for obtaining the quantization value of the electric field data uniformity are as follows: Perform a ratio analysis of the spatial electric field intensity and the spatial electric field intensity threshold, average the results of the ratio analysis, and correct the results of the averaging process using the importance score of the spatial electric field intensity to obtain the first component of the electric field data uniformity. Perform a ratio analysis of the high-frequency pulse frequency and the high-frequency pulse frequency threshold, average the results of the ratio analysis, and correct the results of the averaging process using the importance score of the high-frequency pulse frequency, denoted as the second component of the electric field data uniformity. Perform a ratio analysis of the deviation between the low-frequency electric field frequency and the low-frequency electric field frequency standard value and the low-frequency electric field frequency standard value, average the results of the ratio analysis, and correct the results of the averaging process using the importance score of the low-frequency electric field frequency, denoted as the third component of the electric field data uniformity. Perform a ratio analysis of the deviation between the multi-physical field coupling period and the multi-physical field coupling period standard value and the multi-physical field coupling period standard value, and correct the results of the ratio analysis using the importance score of the multi-physical field coupling period, denoted as the fourth component of the electric field data uniformity. Perform a ratio analysis of the voltage ozone conversion efficiency and the voltage ozone conversion efficiency threshold, average the results of the ratio analysis, and correct the results of the averaging process using the importance score of the voltage ozone conversion efficiency, denoted as the fifth component of the electric field data uniformity. Perform a coupling analysis on the first component of the electric field data uniformity, the second component of the electric field data uniformity, the third component of the electric field data uniformity, the fourth component of the electric field data uniformity, and the fifth component of the electric field data uniformity to obtain the quantization value of the electric field data uniformity. The quantization value of the electric field data uniformity represents the quantization data of the uniformity degree of the applied electric field in each region inside the litchi stack during the litchi preservation process.

6. The litchi fresh-keeping control method based on regulating low-frequency electric field according to claim 4, characterized in that, The specific analysis steps for the control reliability quantization value are as follows: Perform a ratio analysis of the second threshold of the spatial electric field intensity and the spatial electric field intensity, average the results of the ratio analysis, and correct the results of the averaging process using the second importance score of the spatial electric field intensity, denoted as the first component of the control reliability. Perform a ratio analysis of the second standard value of the multi-physical field coupling period and the deviation between the multi-physical field coupling period and the multi-physical field coupling period standard value, and correct the results of the ratio analysis using the second importance score of the multi-physical field coupling period, denoted as the second component of the control reliability. Perform a ratio analysis of the ripple voltage peak value of the power supply output voltage and the DC output voltage to obtain the electric field attenuation compensation coefficient, average the electric field attenuation compensation coefficient, and correct the results of the averaging process using the importance score of the electric field attenuation compensation coefficient, denoted as the third component of the control reliability. The ratio of the deviation between the electric field intensity measured in the central region of the litchi stack and the electric field intensity measured in the edge region of the litchi stack to the electric field intensity measured in the edge region of the litchi stack is analyzed to obtain the power supply ripple coefficient. The power supply ripple coefficient is averaged, and the result of the averaging process is corrected using the importance score of the power supply ripple coefficient, denoted as the fourth component of control reliability; The ratio of the coupling result of the first component of control reliability, the second component of control reliability, and the third component of control reliability to the fourth component of control reliability is analyzed to obtain the control reliability quantization value; The control reliability quantization value represents the stability and reliability of the litchi fresh-keeping control system.

7. The litchi fresh-keeping control method based on adjusting the low-frequency electric field according to claim 1, characterized in that, The specific steps to obtain the optimized litchi fresh-keeping control method are as follows: Obtain the first determination value of the electric field data uniformity quantization value and the second determination value of the control reliability quantization value from the litchi fresh-keeping control database; The electric field data uniformity quantization value and the control reliability quantization value are respectively compared and analyzed with the first determination value of the electric field data uniformity quantization value and the second determination value of the control reliability quantization value to obtain the optimized litchi fresh-keeping control method; The optimized litchi fresh-keeping control method includes the method for optimizing the electric field uniformity of litchi fresh-keeping control and the method for optimizing the control reliability of litchi fresh-keeping control.

8. The litchi fresh-keeping control method based on regulating low-frequency electric field according to claim 7, characterized in that, The method for optimizing the electric field uniformity of litchi fresh-keeping control is as follows: If the electric field data uniformity quantization value is less than or equal to the first determination value of the electric field data uniformity quantization value, the method for optimizing the electric field uniformity of litchi fresh-keeping control is not triggered; If the electric field data uniformity quantization value is greater than the first determination value of the electric field data uniformity quantization value, the method for optimizing the electric field uniformity of litchi fresh-keeping control is triggered. The method for optimizing the electric field uniformity of litchi fresh-keeping control means identifying the closely contacted regions with concentrated electric fields and the void regions with electric field attenuation in the litchi stack based on the monitored electric field intensity data, dynamically adjusting the spacing and angle of the multi-electrode array based on the electric field data uniformity quantization value, and optimizing the narrow pulse parameters by combining the cooperative modulation of the high-frequency pulse frequency and the low-frequency electric field frequency. The electric field intensity data is obtained by real-time monitoring of each region in the litchi stack using a capacitive electric field sensor array.

9. The litchi fresh-keeping control method based on regulating low-frequency electric field according to claim 7, wherein, The method for optimizing the control reliability of litchi fresh-keeping control is as follows: If the control reliability quantization value is greater than or equal to the second determination value of the control reliability quantization value, the method for optimizing the control reliability of litchi fresh-keeping control is not triggered; If the control reliability quantization value is less than the second determination value of the control reliability quantization value, the method for optimizing the control reliability of litchi fresh-keeping control is triggered. The method for optimizing the control reliability of litchi fresh-keeping control means identifying the litchi stacking density based on the electric field intensity and magnetic field intensity, and dynamically adjusting the electrode spacing, high-frequency pulse parameters, and alternating magnetic field frequency based on the control reliability quantization value to achieve the reliability control of litchi fresh-keeping under the synergistic action of multiple physical fields. The electric field intensity and magnetic field intensity are obtained by real-time monitoring of each region in the litchi stack using a capacitive electric field sensor array and a magnetic field sensor.

10. A litchi fresh-keeping control system based on adjusting low-frequency electric fields, characterized in that, It includes a litchi precooling processing module, a litchi fresh-keeping parameter acquisition module, a litchi fresh-keeping parameter quantization evaluation module, and an optimized litchi fresh-keeping control method module: Litchi pre-cooling processing module: used to pre-cool litchi, and stack the pre-cooled litchi to form a litchi stack; Litchi freshness preservation parameter acquisition module: used to apply a low-frequency electric field to the litchi stack through a power supply device, arrange a capacitive electric field sensor array in different regions of the litchi stack, monitor the electric field intensity in each region of the litchi stack in real time, collect the original litchi freshness preservation parameters, and preprocess the original litchi freshness preservation parameters to obtain litchi freshness preservation parameters; Litchi freshness preservation parameter quantization and evaluation module: used to respectively quantify and evaluate the electric field uniformity and the reliability of litchi freshness preservation control through the litchi freshness preservation parameters to obtain the quantization value of electric field data uniformity and the quantization value of control reliability; Optimized litchi freshness preservation control method module: used to compare and analyze the quantization value of electric field data uniformity and the quantization value of control reliability with the first determination value of the quantization value of electric field data uniformity and the second determination value of the quantization value of control reliability in the litchi freshness preservation control database respectively to obtain an optimized litchi freshness preservation control method.

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