Ultralow-temperature refrigerator based on energy-saving control

Abstract

The invention relates to the field of refrigerator energy-saving control, and particularly discloses an ultralow-temperature refrigerator based on energy-saving control, which comprises an article stacking sensing module, an airflow limitation evaluation module, an opening initial setting module and an opening redistribution module. Scanning articles in front of an air outlet in real time through a 3D visual sensor, establishing a three-dimensional point cloud model, and obtaining a relative distance and angle; the airflow blocking rate is calculated based on the point cloud data, and the airflow limitation degree is evaluated in combination with a space pose compensation factor; dynamically adjusting the current air outlet air door opening according to the evaluation result, and cooperatively adjusting the opening of an adjacent air outlet to realize air distribution; and finally, the backflow temperature of an adjacent air outlet is monitored through a temperature sensor, and closed-loop redistribution of the opening degree of the air door is conducted. According to the invention, the space attitude of an object can be accurately sensed, the airflow blocking condition is scientifically evaluated, multi-air-port collaborative energy-saving control is realized, the refrigeration efficiency is effectively improved, the energy consumption is reduced, and the temperature in the cabinet is uniform and stable.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of refrigerator energy-saving control, and relates to an ultra-low temperature refrigerator based on energy-saving control. BACKGROUND

[0002] With the increasing awareness of energy conservation and environmental protection and the continuous expansion of cold chain logistics demand, ultra-low temperature refrigerators are increasingly widely used in the fields of biological medicine, scientific research, food storage, etc. Ultra-low temperature refrigerators usually use multi-air outlet air supply to achieve uniform cooling, but in actual use, the stacking posture and position of the goods in the refrigerator often block part of the air outlet, causing air supply flow obstruction, local temperature unevenness, and refrigeration efficiency decline, thereby causing energy waste and equipment load increase.

[0003] Some attempts have been made in the prior art to perceive obstacles through sensors and adjust damper opening. For example, a refrigerator with air curtain function is proposed in Chinese Patent No. CN112066616B, which detects whether there is an object (such as a human hand) close to the front area of the door body through an infrared distance sensor, and adjusts the damper opening accordingly to avoid direct blowing of cold air to the user, thereby improving the use comfort. However, this scheme can only perceive two-dimensional distance information, cannot obtain the three-dimensional shape and spatial posture of the goods, cannot quantify the degree of air flow obstruction, and lacks the ability to coordinate and dynamically redistribute multiple air outlets, so there are still problems such as low energy efficiency and insufficient temperature control accuracy in complex stacking scenarios.

[0004] Therefore, there is an urgent need for an ultra-low temperature refrigerator system that can perceive the three-dimensional spatial posture of goods in real time, accurately assess the degree of air flow restriction, and realize coordinated energy-saving control of multiple air outlets. SUMMARY

[0005] To solve the above problems, the present application provides an ultra-low temperature refrigerator based on energy-saving control, which realizes the function of energy-saving control of the refrigerator.

[0006] The technical scheme adopted by the present application to solve its technical problems is: the present application provides an ultra-low temperature refrigerator based on energy-saving control, comprising: an article stacking perception module: a 3D vision sensor is used to scan the articles stacked in the front area of the air outlet in real time, establish a three-dimensional point cloud model of the articles, and obtain the relative distance and relative angle between the articles and the air outlet.

[0007] A gas flow restriction evaluation module: based on the three-dimensional point cloud model, the volume occupancy rate in the conical space in the normal direction of the air outlet is analyzed to calculate the air flow obstruction rate, and the relative distance and relative angle are combined to evaluate the air flow restriction degree of the air outlet.

[0008] The opening degree initial setting module: judging whether to reduce the damper opening degree according to the airflow restriction degree of the air outlet, if yes, determining the reduction amount of the damper opening degree, and analyzing the increase amount of the damper opening degree of each adjacent air outlet of the air outlet, controlling the air volume adjusting device to adjust the damper opening degree, if no, keeping the original damper opening degree.

[0009] The opening degree redistribution module: continuously monitoring the backflow temperature of each adjacent air outlet through the temperature sensor, and redistributing the damper opening degree of each adjacent air outlet based on the difference between the backflow temperature of the adjacent air outlet and the set temperature and the difference between the backflow temperatures of the adjacent air outlets.

[0010] Compared with the prior art, the ultra-low temperature refrigerator based on energy-saving control has the following advantages: 1. Accurate perception of the three-dimensional spatial posture of the object: the 3D vision sensor of the present application scans the area in front of the air outlet in real time, constructs a three-dimensional point cloud model of the object, and calculates the relative distance and angle of the object from the air outlet, providing high-precision spatial data support for subsequent airflow restriction evaluation.

[0011] 2. Scientific evaluation of airflow restriction degree: the present application calculates the airflow obstruction rate based on three-dimensional point cloud data, combines with the spatial pose compensation factor, and comprehensively evaluates the airflow restriction degree of the air outlet, overcoming the limitations of relying only on distance or volume judgment, and being more consistent with the actual airflow organization characteristics.

[0012] 3. Dynamic damper opening degree adjustment and collaborative compensation: the present application dynamically adjusts the damper opening degree of the air outlet according to the airflow restriction degree, and collaboratively adjusts the damper opening degree of the adjacent air outlet of the air outlet, realizes intelligent distribution of air volume, avoids local overcooling or overheating, and improves the overall refrigeration efficiency.

[0013] 4. Temperature feedback closed-loop control: the present application redistributes the damper opening degree of the adjacent air outlet by continuously monitoring the backflow temperature of the adjacent air outlet, ensures the uniformity and stability of the temperature in the cabinet, and further improves the energy efficiency and control accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating laborious work.

[0015] Figure 1 The system module connection diagram of the present application.

[0016] Figure 2 The relative position diagram of the object and the air outlet of the present application.

[0017] Figure 3The effective air supply cone space of the air outlet of the application is shown in the schematic diagram. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the application.

[0019] Please refer to Figure 1 The application provides an ultra-low temperature refrigerator based on energy-saving control, which comprises an article stacking sensing module, an airflow restriction evaluation module, an opening degree initial setting module and an opening degree redistribution module.

[0020] The airflow restriction evaluation module is connected with the article stacking sensing module and the opening degree initial setting module, and the opening degree redistribution module is connected with the opening degree initial setting module.

[0021] The article stacking sensing module scans the articles stacked in the region in front of the air outlet in real time through a 3D visual sensor, establishes a three-dimensional point cloud model of the articles, and obtains the relative distance and the relative angle between the articles and the air outlet.

[0022] Further, the specific working process of the article stacking sensing module is as follows: the 3D visual sensor deployed near the air outlet scans the articles stacked in the region in front of the air outlet in real time, and establishes a three-dimensional point cloud model of the articles based on the sensor data.

[0023] Please refer to Figure 2 The center point of the air outlet is made as a normal line of the plane where the center point is located, and is recorded as a reference line, the length of the line segment connecting the center point of the article and the center point of the air outlet is obtained , and the included angle between the line segment and the reference line is obtained . The included angle is recorded as the relative angle between the article and the air outlet.

[0024] The relative distance between the article and the air outlet is calculated by the formula . .

[0025] It should be noted that in the application, the ultra-low temperature refrigerator is uniformly distributed with a plurality of air outlets, and a 3D visual sensor is correspondingly deployed near each air outlet, which is used to collect three-dimensional point cloud data of the articles stacked in the region in front of the air outlet to reconstruct a three-dimensional point cloud model.

[0026] It should be noted that the 3D visual sensor includes but is not limited to a ToF sensor or a structured light camera.

[0027] In the embodiment, the application scans the area in front of the air outlet in real time through a 3D vision sensor, constructs a three-dimensional point cloud model of the object, and calculates the relative distance and angle of the object from the air outlet, thereby providing high-precision spatial data support for subsequent airflow restriction evaluation.

[0028] The airflow restriction evaluation module analyzes the volume occupancy rate in the conical space in the normal direction of the air outlet based on the three-dimensional point cloud model, calculates the airflow obstruction rate, and evaluates the airflow restriction degree of the air outlet in combination with the relative distance and relative angle.

[0029] Further, the specific working process of calculating the airflow obstruction rate in the airflow restriction evaluation module is as follows: Figure 3 Referring to FIG. 1, the effective air supply conical space of the air outlet is constructed with the center point of the air outlet as the vertex and the normal direction of the air outlet as the central axis, and the opening angle and the detection depth of the conical space are determined.

[0030] D2: A three-dimensional coordinate system established with the center point of the 3D vision sensor as the origin is referred to as the sensor coordinate system.

[0031] Based on the three-dimensional point cloud model of the object, the original point cloud data is obtained and preliminary noise reduction processing is performed to obtain the preprocessed point cloud and its three-dimensional coordinates in the sensor coordinate system.

[0032] D3: A three-dimensional coordinate system established with the center point of the air outlet as the origin and the normal direction of the air outlet as the Z-axis is referred to as the air outlet coordinate system.

[0033] D4: The offset parameters of the center point of the 3D vision sensor relative to the center point of the air outlet are measured, including the position offset and the angle offset.

[0034] Based on the offset parameters, a fixed transformation matrix from the sensor coordinate system to the air outlet coordinate system is constructed.

[0035] D5: The three-dimensional coordinates of the preprocessed point cloud in the sensor coordinate system are converted to the air outlet coordinate system by applying the transformation matrix to obtain the converted point cloud data.

[0036] D6: Based on the three-dimensional coordinates of the converted point cloud, the point cloud located in the effective air supply conical space is selected and referred to as the effective space point cloud.

[0037] D7: According to the preset equal volume principle, the effective air supply conical space is divided into a plurality of cubic units, and each unit is referred to as a voxel.

[0038] D8: It is judged whether each voxel contains effective space point cloud: if yes, the voxel is referred to as occupied voxel, otherwise, it is referred to as unoccupied voxel.

[0039] Count the number of occupied voxels and multiply by the volume of a single voxel to get the volume of the effective plenum space occupied by the object .

[0040] D9: Calculate the total volume of the effective plenum cone space using the standard cone volume formula based on the opening angle and the probe depth of the cone .

[0041] D10: Calculate the air flow obstruction rate of the outlet using the formula . .

[0042] Note that the normal direction of the outlet is the main direction of air supply.

[0043] Note that the effective plenum space of the outlet is defined as a cone space because it conforms to the diffusion pattern of cold air after being sent out from the outlet.

[0044] Note that the opening angle corresponds to the thickness of the cone, and the probe depth corresponds to the length of the cone.

[0045] Note that the point cloud is preliminarily denoised to remove obvious isolated outliers in space.

[0046] Note that since the 3D vision sensor is usually installed near the outlet rather than the center, a fixed transformation matrix is needed to convert the three-dimensional coordinates of all point clouds of the object in the sensor coordinate system to the outlet coordinate system, and then to facilitate the judgment of whether each point cloud is located in the effective plenum cone space of the outlet.

[0047] Note that the position offset refers to the distance between the center point of the 3D vision sensor and the center point of the outlet in three directions; the angle offset refers to the angle between the optical axis of the 3D vision sensor and the normal direction of the outlet.

[0048] Note that the voxel is a tiny cubic unit. The size of the voxel determines the accuracy of the calculation. In a specific embodiment, the size of the voxel is 0.5cmx0.5cmx0.5cm.

[0049] Note that if there is at least one effective space point cloud in a voxel, it is considered to be blocked and recorded as an occupied voxel.

[0050] Note that the air flow obstruction rate refers to the ratio of the volume of the object that hinders the air flow organization in front of the outlet to the theoretical effective plenum space volume of the outlet. The value is a scalar between 0 and 1. ​ This indicates that the road ahead is completely clear. This indicates that the road ahead is completely blocked.

[0051] It should be noted that when calculating the airflow blockage rate, in addition to choosing the conical space in the direction of the outlet normal, other specific solid angle spaces can also be selected, such as pyramid-shaped space, hemispherical space, custom polyhedral space, dynamic space based on velocity threshold, etc., depending on different application scenarios, accuracy requirements and flow characteristics.

[0052] It should be noted that the airflow blockage rate can also be calculated by the point cloud density within the cone-shaped space along the normal direction of the air outlet.

[0053] Furthermore, the specific process for determining the opening angle and detection depth of the conical space is as follows: through fluid dynamics experiments, the diffusion pattern of cold air at the air outlet under the current wind speed and current damper opening is tested.

[0054] The maximum diffusion angle of the cold air and its farthest distance from the air outlet are obtained to construct an effective air supply cone space for the air outlet. The maximum diffusion angle and the farthest distance are set as the opening angle and detection depth of the cone space, respectively.

[0055] In another specific embodiment, the opening angle and detection depth of the effective air supply cone space of the air outlet are determined by CFD simulation.

[0056] Furthermore, the specific process of screening point clouds located within the effective air supply cone space is as follows: the opening angle and detection depth of the effective air supply cone space at the air outlet are respectively denoted as... and , .

[0057] Traverse each point cloud after transformation ,in This indicates the point cloud number. .

[0058] Select point clouds that simultaneously meet the following two conditions and record them as valid spatial point clouds.

[0059] (1) Distance condition: .

[0060] (2) Angle conditions: .

[0061] It should be noted that the distance condition restricts the point cloud to be located in front of the air outlet and within the detection depth, that is, within the length range of the point cloud in the cone space; the angle condition restricts the lateral offset of the point cloud to not exceed the cone radius corresponding to its z-axis depth, that is, within the opening angle range of the point cloud in the cone space.

[0062] Furthermore, the specific working process of evaluating the degree of airflow limitation at the air outlet in the airflow limitation assessment module is as follows: based on the relative distance and relative angle between the object and the air outlet, the preset mapping relationship between the relative distance and relative angle and the airflow limitation compensation factor is queried, the airflow limitation compensation factor corresponding to the relative distance and relative angle is determined, and the factors are accumulated to obtain the airflow limitation compensation amount of the air outlet.

[0063] Based on the airflow blockage rate and airflow limitation compensation at the air outlet, the degree of airflow limitation at the air outlet is obtained through weighted fusion analysis. , .

[0064] It should be noted that, through fluid dynamics simulation and wind tunnel experiments, the actual obstruction of the airflow field at the outlet under different relative distances and relative angles was analyzed. Quantitative correspondences between relative distance and airflow limitation compensation factor, and between relative angle and airflow limitation compensation factor, were established and preset in the form of lookup tables or fitting functions. The closer the relative distance and the smaller the relative angle, the larger the airflow limitation compensation factor.

[0065] It should be noted that the weights of the airflow blockage rate and the airflow limitation compensation amount can be set based on fluid dynamics experience, or they can be obtained through a limited number of air supply test data. For example, historical data on the outlet wind speed and temperature distribution under different blockage conditions can be collected first, and then the correlation coefficients between the airflow blockage rate and the airflow limitation compensation amount and the air supply efficiency can be calculated. Regression analysis or principal component analysis can be used to determine the contribution of the two to the degree of airflow limitation. Finally, after normalization, the contribution is converted into corresponding weights and their sum is 1.

[0066] It should be noted that the weight of the airflow blockage rate is greater than the weight of the airflow limitation compensation amount.

[0067] It should be noted that when assessing the degree of airflow restriction at the air outlet, in addition to the airflow obstruction rate, the relative distance and angle between the object and the air outlet are further introduced. This is because different distances and angles significantly affect the actual obstruction pattern and energy loss of the airflow. Even small objects close to or directly facing the air outlet can cause severe local airflow turbulence. The purpose of this is to quantify the influence of the above spatial pose factors through a compensation factor, correcting the deviation that may be caused by relying solely on the volume obstruction rate, thereby more accurately and comprehensively reflecting the true airflow restriction situation.

[0068] In this embodiment, the present invention calculates the airflow obstruction rate based on three-dimensional point cloud data and combines it with spatial pose compensation factors to comprehensively evaluate the degree of airflow restriction at the air outlet, overcoming the limitations of relying solely on distance or volume for judgment, and is more in line with the actual airflow organization characteristics.

[0069] The initial setting module determines whether to reduce the damper opening based on the degree of airflow restriction at the air outlet. If so, it determines the amount of reduction in the damper opening and analyzes the amount of increase in the damper opening of each adjacent air outlet, and controls the airflow regulating device to adjust the damper opening. If not, it maintains the original damper opening.

[0070] Furthermore, the specific working process of the initial opening setting module is as follows: S1: Determine whether the airflow restriction degree of the air outlet is greater than or equal to the preset first threshold. If so, the damper opening needs to be reduced and S2 is executed. If not, the current damper opening of the air outlet remains unchanged.

[0071] S2: Based on the preset correspondence between the airflow restriction range and the damper opening, determine the final damper opening of the air outlet, and calculate the reduction amount of the air outlet damper opening in combination with its initial damper opening.

[0072] S3: Based on the air outlet layout topology of the ultra-low temperature freezer, identify each adjacent air outlet.

[0073] S4: Analyze the degree of airflow restriction at each adjacent air outlet. Based on the preset compensation rule for adjacent air outlets, calculate the increase in the damper opening of each adjacent air outlet. The compensation rule is defined by the following formula: ,in Indicates the first The increase in the opening of the damper of a nearby air outlet , This indicates the amount by which the air outlet damper opening is reduced. Represents the preset weighting coefficients and satisfies , Indicates the first The degree of airflow restriction near the air outlet.

[0074] S5: Air volume control device, which adjusts the opening of the damper of the air outlet and the corresponding adjacent air outlet according to the calculated reduction and increase.

[0075] It should be noted that when setting the corresponding rules for the airflow restriction range and the damper opening, based on fluid simulation and duct characteristic experiments, the minimum air volume required to maintain the target temperature inside the cabinet under different airflow restriction ranges is analyzed, a quantitative matching relationship between the airflow restriction range and the damper opening is established, and it is preset in the form of a lookup table or piecewise function.

[0076] It should be noted that the method for analyzing the degree of airflow restriction at each adjacent air outlet is based on the same principle as the method for analyzing the degree of airflow restriction at the air outlet itself.

[0077] It should be noted that the weighting coefficient in the adjacent air outlet compensation rule is an empirical value less than 1, used to allocate the compensation air volume and avoid over-compensation. In one specific embodiment, the weighting coefficient is set to 0.7.

[0078] It should be noted that the more unobstructed the airflow is near the vent, the more compensating airflow will be received.

[0079] It should be noted that the airflow distribution strategy of the ultra-low temperature freezer is to suppress the airflow at the air outlet with restricted airflow and enhance the airflow at the adjacent unobstructed air outlet. In this invention, the air velocity at each air outlet of the ultra-low temperature freezer is uniformly adjusted to ensure the basic airflow circulation and efficiency of the entire refrigeration system. However, the damper opening of each air outlet is independently adjustable to achieve precise temperature zone control and airflow distribution. Therefore, the specific adjustment measures for the airflow at each air outlet in this invention are as follows: for air outlets with high airflow restriction, the damper opening is reduced to decrease the airflow, thereby preventing cold air from directly blowing onto items, causing waste and localized overcooling; at the same time, the damper opening of the adjacent air outlet with lower airflow restriction is increased to increase the airflow, thereby guiding the cold airflow around the obstruction and compensating for the cooling in the blocked area.

[0080] It should be noted that each air outlet inside the ultra-low temperature freezer is equipped with an airflow regulating device. This device is a blade-type damper driven by a stepper motor or servo motor, used to independently adjust the opening of the air outlet, thereby regulating the airflow. The dampers are installed at each air outlet or in an independent branch duct connected to each air outlet.

[0081] Furthermore, the correspondence between the airflow restriction range and the damper opening is as follows: ,in Indicates the final damper opening. This indicates the initial damper opening. This indicates the set minimum damper opening. , The first and second thresholds represent the preset degree of airflow restriction, respectively. .

[0082] It should be noted that the setting of the first and second thresholds for the degree of airflow restriction is based on fluid dynamics simulation and wind tunnel test data, and is determined by analyzing the inflection point of air supply efficiency under different obstruction conditions: the critical point at which the air supply efficiency begins to decrease significantly is set as the first threshold, and the critical point at which the air supply efficiency drops to the lower limit of the acceptable range and requires mandatory intervention to maintain the basic operation of the system is set as the larger second threshold.

[0083] It should be noted that the minimum damper opening is set with the primary principle of ensuring the safe and stable operation of the ultra-low temperature freezer refrigeration system. The minimum opening that this model of damper can maintain under the premise that the risk of frosting is controllable and the fan motor is not overloaded or surged is determined by testing and taking into account the minimum circulating air volume requirements of the system.

[0084] In one specific embodiment, the first threshold and the second threshold for the degree of airflow restriction are 0.2 and 0.6, respectively, and the minimum damper opening is set to 10%.

[0085] It should be noted that when there is a slight blockage, the airflow is supplied at the normal volume; the more severe the blockage, the more the airflow at the outlet is reduced; when there is a high blockage, the damper opening is reduced to the minimum set value to maintain only a small amount of ventilation and prevent the outlet from being completely blocked by frost.

[0086] In this embodiment, the present invention dynamically adjusts the opening of the air outlet damper according to the degree of airflow restriction, and coordinates the opening of the dampers of adjacent air outlets to achieve intelligent distribution of air volume, which avoids local overcooling or overheating and improves the overall cooling efficiency.

[0087] The opening redistribution module continuously monitors the return temperature of each adjacent air outlet through a temperature sensor. Based on the difference between the return temperature of the adjacent air outlet and the set temperature, as well as the difference between the return temperatures of adjacent air outlets, the module redistributes the opening of the dampers of each adjacent air outlet.

[0088] Furthermore, the specific working process of the opening redistribution module is as follows: T1: The high-precision temperature sensors deployed in the recirculation area of ​​each adjacent air outlet continuously monitor the recirculation temperature of each adjacent air outlet.

[0089] T2: Determine whether the recirculation temperature of each adjacent air outlet meets the following conditions simultaneously: (1) The difference between the recirculation temperature of all adjacent air outlets and the set recirculation temperature is within the preset allowable range.

[0090] (2) The return temperature difference between any two adjacent air outlets is less than the set threshold; if both conditions are met, the current damper opening of each adjacent air outlet remains unchanged; otherwise, execute T3.

[0091] T3: Identify the adjacent air outlets with high and low return flow temperatures, and according to the preset damper opening unit adjustment amount, increase the damper opening of the adjacent air outlets with high temperature and decrease the damper opening of the adjacent air outlets with low temperature in a gradient adjustment manner until the return flow temperature meets the conditions described in T2.

[0092] It should be noted that by recording the spatial posture of different items and their corresponding optimal damper opening configuration, when a similar spatial posture is identified again, the historical optimal configuration will be used as the basis for the initial damper opening control signal to speed up the adjustment and further optimize energy efficiency.

[0093] Furthermore, the specific process for identifying adjacent air outlets with excessively high and low recirculation temperatures is as follows: the recirculation temperature of each adjacent air outlet is compared with the set recirculation temperature.

[0094] If the difference between the return temperature and the set temperature of a certain air outlet exceeds the allowable range, and its return temperature is higher than the set value, then the air outlet is recorded as a neighboring air outlet with a higher temperature. If its return temperature is lower than the set value, then it is recorded as a neighboring air outlet with a lower temperature.

[0095] Calculate the average return temperature of all adjacent air outlets, and determine the fluctuation range of the return temperature based on the preset threshold for the difference in return temperature between adjacent air outlets.

[0096] If the return temperature of a certain air outlet is higher than the upper limit of the fluctuation range, it is recorded as a nearby air outlet with a relatively high temperature (Category II).

[0097] If the return temperature of a certain air outlet is lower than the lower limit of the fluctuation range, it is recorded as a nearby air outlet with a lower temperature in the second category.

[0098] By summarizing the nearby air outlets with higher and lower temperatures in categories one and two, a set of nearby air outlets with higher and lower return flow temperatures is obtained.

[0099] In this embodiment, the present invention continuously monitors the return temperature of adjacent air outlets and redistributes the opening of the dampers of adjacent air outlets to ensure uniform and stable temperature inside the cabinet, thereby further improving energy efficiency and control accuracy.

[0100] In this embodiment, the present invention effectively reduces fan energy consumption, prevents local frost and system overload, and extends equipment life by reducing the airflow of blocked air vents and increasing the airflow of unobstructed air vents.

[0101] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0102] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0103] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0104] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0105] Finally, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An ultra-low temperature freezer based on energy-saving control, characterized in that, include: The item stacking perception module uses a 3D vision sensor to scan the items stacked in front of the air outlet in real time, establish a three-dimensional point cloud model of the items, and obtain the relative distance and relative angle between the items and the air outlet. The airflow restriction assessment module, based on the three-dimensional point cloud model, analyzes the volume occupancy rate in the cone-shaped space along the normal direction of the air outlet to calculate the airflow blockage rate, and combines the relative distance and relative angle to assess the degree of airflow restriction at the air outlet. The initial setting module determines whether to reduce the damper opening based on the degree of airflow restriction at the air outlet. If so, it determines the amount of reduction in the damper opening and analyzes the amount of increase in the damper opening of each adjacent air outlet, controlling the airflow regulating device to adjust the damper opening. If not, it maintains the original damper opening. The opening redistribution module continuously monitors the return temperature of each adjacent air outlet through a temperature sensor. Based on the difference between the return temperature of the adjacent air outlet and the set temperature, as well as the difference between the return temperatures of adjacent air outlets, it redistributes the opening of the dampers of each adjacent air outlet.

2. The ultra-low temperature freezer based on energy-saving control according to claim 1, characterized in that: The specific working process of the item stacking sensing module is as follows: The 3D vision sensors deployed near the air outlet are used to scan the items piled up in front of the air outlet in real time, and a three-dimensional point cloud model of the items is built based on the sensor data. Draw the normal to the plane containing the center point of the air outlet and mark it as the baseline. Obtain the length of the line connecting the center point of the object and the center point of the air outlet. And obtain the angle between the connecting line and the baseline. and The included angle is recorded as the relative angle between the item and the air outlet; according to and Calculate the relative distance between the item and the air outlet. .

3. The ultra-low temperature freezer based on energy-saving control according to claim 1, characterized in that: The specific process for calculating the airflow blockage rate in the airflow limitation assessment module is as follows: D1: Construct an effective air supply cone space for the air outlet with the center point of the air outlet as the vertex and the normal direction of the air outlet as the central axis, and determine the opening angle and detection depth of the cone space. D2: The three-dimensional coordinate system established with the center point of the 3D vision sensor as the origin is denoted as the sensor coordinate system; Based on the 3D point cloud model of the object, the original point cloud data is acquired and preliminary noise reduction is performed to obtain the preprocessed point cloud and its 3D coordinates in the sensor coordinate system. D3: The three-dimensional coordinate system established with the center point of the air outlet as the origin and the normal direction of the air outlet as the Z-axis is denoted as the air outlet coordinate system; D4: Measure the offset parameters of the center point of the 3D vision sensor relative to the center point of the air outlet, including position offset and angle offset; Based on the offset parameters, a fixed transformation matrix is ​​constructed from the sensor coordinate system to the air outlet coordinate system; D5: Apply the transformation matrix to transform the three-dimensional coordinates of the preprocessed point cloud in the sensor coordinate system to the air outlet coordinate system to obtain the transformed point cloud data; D6: Based on the three-dimensional coordinates of the transformed point cloud, filter the point cloud located within the effective air supply cone space and denot it as the effective space point cloud; D7: According to the preset principle of equal volume, the effective air supply cone space is divided into several cubic units, and each unit is denoted as a voxel; D8: Determine whether each voxel contains a valid spatial point cloud: if so, record the voxel as an occupied voxel; otherwise, record it as an unoccupied voxel. Count the number of all occupied voxels and multiply it by the volume of a single voxel to obtain the volume occupied by the object within the effective air supply space. D9: Calculate the total volume of the space based on the opening angle and detection depth of the effective air supply cone space using the standard cone volume formula; D10: Calculate the airflow blockage rate at the air outlet.

4. The ultra-low temperature freezer based on energy-saving control according to claim 3, characterized in that: The specific process for determining the opening angle and detection depth of the conical space is as follows: The diffusion pattern of cold air at the air outlet under the current wind speed and damper opening was tested through fluid dynamics experiments. The maximum diffusion angle of the cold air and its farthest distance from the air outlet are obtained to construct an effective air supply cone space for the air outlet. The maximum diffusion angle and the farthest distance are set as the opening angle and detection depth of the cone space, respectively.

5. The ultra-low temperature freezer based on energy-saving control according to claim 3, characterized in that: The specific process for screening point clouds located within the effective air supply cone space is as follows: The opening angle and detection depth of the effective air supply cone space at the air outlet are respectively denoted as... and , ; Traverse each point cloud after transformation ,in This indicates the point cloud number. ; Select point clouds that simultaneously meet the following two conditions and record them as valid spatial point clouds; (1) Distance condition: ; (2) Angle conditions: .

6. The ultra-low temperature freezer based on energy-saving control according to claim 1, characterized in that: The specific process for evaluating the degree of airflow restriction at the air outlet in the airflow restriction assessment module is as follows: Based on the relative distance and relative angle between the object and the air outlet, the mapping relationship between the preset relative distance and relative angle and the airflow limitation compensation factor is queried, the airflow limitation compensation factor corresponding to the relative distance and relative angle is determined, and the factors are accumulated to obtain the airflow limitation compensation amount of the air outlet. Based on the airflow blockage rate and airflow limitation compensation at the air outlet, the degree of airflow limitation at the air outlet is obtained through weighted fusion analysis. , .

7. The ultra-low temperature freezer based on energy-saving control according to claim 1, characterized in that: The specific working process of the initial opening setting module is as follows: S1: Determine whether the airflow restriction at the air outlet is greater than or equal to the preset first threshold. If yes, the damper opening needs to be reduced and S2 needs to be executed. If no, the current damper opening at the air outlet remains unchanged. S2: Based on the preset correspondence between the airflow restriction range and the damper opening, determine the final damper opening of the air outlet, and calculate the reduction amount of the air outlet damper opening in combination with its initial damper opening. S3: Based on the air outlet layout topology of the ultra-low temperature freezer, identify each adjacent air outlet. S4: Analyze the degree of airflow restriction at each adjacent air outlet. Based on the preset compensation rule for adjacent air outlets, calculate the increase in the damper opening of each adjacent air outlet. The compensation rule is defined by the following formula: ,in Indicates the first The increase in the opening of the damper of a nearby air outlet , This indicates the amount by which the air outlet damper opening is reduced. Represents the preset weighting coefficients and satisfies , Indicates the first The degree of airflow restriction near the air outlet; S5: Air volume control device, which adjusts the opening of the damper of the air outlet and the corresponding adjacent air outlet according to the calculated reduction and increase.

8. The ultra-low temperature freezer based on energy-saving control according to claim 6, characterized in that: The correspondence between the airflow restriction range and the damper opening is as follows: ,in Indicates the final damper opening. This indicates the initial damper opening. This indicates the set minimum damper opening. , The first and second thresholds represent the preset degree of airflow restriction, respectively. .

9. The ultra-low temperature freezer based on energy-saving control according to claim 1, characterized in that: The specific working process of the opening redistribution module is as follows: T1: Continuously monitors the recirculation temperature of each adjacent air outlet by using high-precision temperature sensors deployed in the recirculation area of ​​each adjacent air outlet; T2: Determine whether the return flow temperature of each adjacent air outlet simultaneously meets the following conditions: (1) The difference between the recirculation temperature of all adjacent air outlets and the set recirculation temperature is within the preset allowable range; (2) The return temperature difference between any two adjacent air outlets is less than the set threshold; if both conditions are met, the current damper opening of each adjacent air outlet remains unchanged; otherwise, execute T3. T3: Identify the adjacent air outlets with high and low return flow temperatures, and according to the preset damper opening unit adjustment amount, increase the damper opening of the adjacent air outlets with high temperature and decrease the damper opening of the adjacent air outlets with low temperature in a gradient adjustment manner until the return flow temperature meets the conditions described in T2.

10. An ultra-low temperature freezer based on energy-saving control according to claim 9, characterized in that: The specific process for identifying adjacent air outlets with excessively high and low return flow temperatures is as follows: Compare the recirculation temperature of each adjacent air outlet with the set recirculation temperature; If the difference between the return temperature and the set temperature of a certain air outlet exceeds the allowable range, and its return temperature is higher than the set value, then the air outlet is recorded as a neighboring air outlet with a higher temperature. If its return temperature is lower than the set value, then it is recorded as a neighboring air outlet with a lower temperature. Calculate the average return temperature of all adjacent air outlets, and determine the fluctuation range of the return temperature based on the preset threshold of the return temperature difference between adjacent air outlets. If the return temperature of a certain air outlet is higher than the upper limit of the fluctuation range, it is recorded as a nearby air outlet with a relatively high temperature (Category II). If the return temperature of a certain air outlet is lower than the lower limit of the fluctuation range, it is recorded as a Class II adjacent air outlet with a lower temperature. By summarizing the nearby air outlets with higher and lower temperatures in categories one and two, a set of nearby air outlets with higher and lower return flow temperatures is obtained.

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