Humidity control method and system for switch cabinet

Abstract

The invention relates to the field of automatic control, in particular to a humidity control method and system for a switch cabinet, and the method comprises the steps: obtaining the temperature values and humidity values of a plurality of time points in the switch cabinet, and calculating the dew point temperature in the switch cabinet based on the temperature value and humidity value of a high-temperature region at the current moment. In consideration of unbalanced temperature distribution in the switch cabinet, whether condensate water is generated in the low-temperature area is mainly considered, and the temperature of the low-temperature area is mainly influenced by the heat transfer effect of the high-temperature area and the environment where the low-temperature area is located. Therefore, the temperature range of the low-temperature region is estimated on the basis of a pre-constructed temperature distribution model, the temperature value of the high-temperature region, and the ambient temperature. And determining whether the temperature of the low-temperature area is lower than the dew point temperature or not through trend analysis and dew point temperature comparison. And if the possibility exists, the water vapor condensation risk is speculated to exist. When water vapor condensation risks exist in the low-temperature area of the switch cabinet, the dehumidification module is controlled to dehumidify the interior of the switch cabinet, and water vapor condensation is avoided.

Description

Technical Field

[0001] The invention relates to the field of automatic control, and in particular to a humidity control method and system for a switch cabinet. Background Art

[0002] Switchgear is an electrical device used in power systems, mainly used to distribute, control and protect electrical energy. It consists of various types of switchgear and other auxiliary equipment that work together to ensure the safe and reliable operation of the power system.

[0003] Switch cabinets installed outdoors are susceptible to air condensation and high humidity in certain weather conditions. Therefore, in the prior art, a condensation module is added to the outside of the switch cabinet to condense the water vapor in the air and then send dry air into the switch cabinet. However, the continuous operation of the condensation module will bring high operating costs. Therefore, in the prior art, a humidity threshold is set to control the operation of the condensation module. However, the temperature distribution inside the switch cabinet is not the same everywhere, so this control method may also cause condensation in the switch cabinet. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a humidity control method and system for a switch cabinet to solve the problems in the background technology.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A humidity control method for a switch cabinet of the present invention comprises the following steps: Obtain the internal temperature value and internal humidity value at multiple time points in the switch cabinet; and obtain the ambient temperature value of the environment where the switch cabinet is located at the current time point and the temperature prediction values ​​at multiple future time points, wherein the multiple time points include the current time point, and the internal temperature value is the temperature value of the high-temperature area of ​​the switch cabinet, and the high-temperature area includes the area where the main busbar connection point is located, the area where the circuit breaker is located, the area where the contactor and other high-power electrical components are located, the transformer room, the cable inlet and outlet terminals, and the area where the heating device is located; The dew point temperature inside the switch cabinet is calculated based on the internal temperature value and the internal humidity value at the current time point; and the temperature range of the low-temperature area in the switch cabinet is determined based on the internal temperature value at the current time point, the ambient temperature value at the current time point and a pre-constructed temperature distribution model, wherein the temperature distribution model includes the temperature range of the low-temperature area corresponding to a plurality of internal and external temperature units, each internal and external temperature unit includes an internal temperature value range and an ambient temperature value range, and the low-temperature area includes the top and the area close to the top plate, the bottom and part of the area close to the ground, the area where the vents are located, the leeward side or the shielded area, the area away from the main heat source, and the standby equipment or line area in a non-working state; Determine the temperature difference change trend between the high temperature area and the low temperature area in the switch cabinet based on the internal temperature values ​​at multiple time points and the temperature prediction values ​​at multiple future time points, and make a water vapor condensation risk determination based on the dew point temperature, the temperature range of the low temperature area and the temperature difference change trend; When there is a risk of water vapor condensation in the switch cabinet, the dehumidification module in the switch cabinet is controlled to dehumidify the switch cabinet.

[0006] In one embodiment of the present application, controlling the dehumidification module in the switch cabinet to dehumidify the switch cabinet includes: S1, controlling the dehumidification module to dehumidify the air in the switch cabinet at rated power for a target time, and reacquiring the internal temperature value and the internal humidity value after dehumidification; S2, updating the dew point temperature based on the re-acquired internal temperature value and internal humidity value; S3, based on the updated dew point temperature, the temperature range of the low-temperature area and the temperature difference change trend, determine whether there is a risk of water vapor condensation in the switch cabinet. If there is a risk of water vapor condensation, return to step S1 until there is no risk of water vapor condensation; if there is no risk of water vapor condensation, control the dehumidification module to stop dehumidification.

[0007] In one embodiment of the present application, the dew point temperature The mathematical representation of is:

[0008]

[0009] In the formula, is the internal humidity value, is the internal temperature value, is an intermediate variable.

[0010] In one embodiment of the present application, the process of constructing the temperature distribution model includes: Acquire a plurality of historical sample data, wherein the historical sample data includes an overall infrared thermal image of the switch cabinet, an ambient temperature value of an environment where the switch cabinet is located, and an internal temperature value at the same time point; Reading the temperature value of one or more low-temperature areas from the overall infrared thermal image of the switch cabinet; Dividing multiple historical sample data based on multiple pre-divided internal temperature value ranges to obtain multiple data units; and dividing each data unit based on multiple pre-divided ambient temperature value ranges to obtain multiple internal and external temperature units; and density clustering multiple historical sample data in the multiple internal and external temperature units based on the temperature value of the low temperature area to obtain multiple data clusters; The data cluster that meets the first target condition is used as the target cluster, wherein the first target condition includes: the number of historical sample data is greater than a preset number threshold, and the variance of the temperature values ​​of all low temperature areas is less than a preset variance threshold; Calculate the mean temperature value of the low temperature area of ​​all historical sample data in the target cluster and standard deviation , and based on the mean of the temperature values and standard deviation Temperature range for building multiple target clusters ; A temperature distribution model is constructed based on a plurality of internal and external temperature units and temperature ranges of low temperature areas corresponding to the plurality of internal and external temperature units.

[0011] In one embodiment of the present application, the temperature difference change trend between the high temperature area and the low temperature area in the switch cabinet is determined based on the internal temperature values ​​at multiple time points and the temperature prediction values ​​at multiple future time points, including: Calculating the temperature trend in the switch cabinet based on the internal temperature values ​​at multiple time points, and determining the temperature trend of the ambient temperature based on the temperature prediction values ​​at multiple future time points, wherein the temperature trend includes an upward trend, a downward trend, and a trend without unidirectional change; When the temperature trend in the switch cabinet and the ambient temperature is an upward trend or a downward trend, calculate the change amount; When one of the second target conditions is met, it is predicted that the temperature difference between the high-temperature area and the low-temperature area in the switch cabinet has a tendency to increase, wherein the second target condition includes: the switch cabinet is on an upward trend and the ambient temperature is on a downward trend; the switch cabinet is on an upward trend and the ambient temperature has no unidirectional change trend; the switch cabinet is on an upward trend and the ambient temperature is on an upward trend, and the change in the switch cabinet is greater than the change in the environment; the switch cabinet has no unidirectional change trend and the ambient temperature has a downward trend.

[0012] In one embodiment of the present application, the process of determining the temperature trend includes: Mapping the temperature values ​​at multiple time points into a two-dimensional coordinate system, wherein the horizontal axis of the two-dimensional coordinate system is the time axis, the vertical axis of the two-dimensional coordinate system is the temperature axis, and the temperature values ​​are internal temperature values ​​or temperature prediction values; Slide along the time axis based on the pre-built sliding window, and calculate the average temperature value of all time points in the sliding window at each sliding. ,in, Indicates the sliding order; When any two adjacent average values ​​satisfy: , it is determined that the temperature in the switch cabinet is decreasing; when any two adjacent average values ​​satisfy: , it is determined that the temperature in the switch cabinet is on an upward trend; otherwise, it is determined that there is no unidirectional change trend.

[0013] In one embodiment of the present application, the water vapor condensation risk is determined based on the dew point temperature, the temperature range of the low temperature area, and the temperature difference change trend, including: The lower limit of the temperature range of the low temperature region is With the dew point temperature Make a comparison; exist When , it is determined that there is a risk of water vapor condensation at the current time point; when , , and when the temperature difference between the high temperature area and the low temperature area in the switch cabinet tends to increase, it is determined that the switch cabinet has a risk of water vapor condensation at a future time point, among which, is the set temperature difference threshold.

[0014] In one embodiment of the present application, the dehumidification module is a semiconductor cooling module, and a drainage hole is provided at the bottom of the dehumidification module, and the drainage hole discharges condensed water out of the switch cabinet through a pipe.

[0015] In one embodiment of the present application, it also includes: When there is a risk of condensation in the switch cabinet, an alarm message is sent to the target object.

[0016] The present application also provides a humidity control system for a switch cabinet, comprising: An acquisition module is used to acquire the internal temperature value and internal humidity value at multiple time points in the switch cabinet; and to acquire the ambient temperature value of the environment in which the switch cabinet is located at the current time point and the temperature prediction values ​​at multiple future time points, wherein the multiple time points include the current time point, and the internal temperature value is the temperature value of the high-temperature area of ​​the switch cabinet, and the high-temperature area includes the area where the main busbar connection point is located, the area where the circuit breaker is located, the area where the contactor and other high-power electrical components are located, the transformer room, the cable inlet and outlet terminals, and the area where the heating device is located; A temperature analysis module is used to calculate the dew point temperature inside the switch cabinet based on the internal temperature value and the internal humidity value at the current time point; and determine the temperature range of the low-temperature area in the switch cabinet based on the internal temperature value at the current time point and the ambient temperature value at the current time point and a pre-constructed temperature distribution model, wherein the temperature distribution model includes the temperature range of the low-temperature area corresponding to a plurality of internal and external temperature units, each of which includes an internal temperature value range and an ambient temperature value range, and the low-temperature area includes the top and the area close to the top plate, the bottom and the partial area close to the ground, the area where the vents are located, the leeward side or the shielded area, the area away from the main heat source, and the standby equipment or line area in a non-working state; A risk determination module, for determining the temperature difference variation trend between the high temperature area and the low temperature area in the switch cabinet based on the internal temperature values ​​at multiple time points and the temperature prediction values ​​at multiple future time points, and for performing water vapor condensation risk determination based on the dew point temperature, the temperature range of the low temperature area and the temperature difference variation trend; The dehumidification control module is used to control the dehumidification module in the switch cabinet to dehumidify the switch cabinet when there is a risk of water vapor condensation in the switch cabinet.

[0017] The beneficial effects of the present invention are as follows: a humidity control method and system for a switch cabinet of the present invention obtains the temperature and humidity values ​​at multiple time points inside the switch cabinet, and calculates the dew point temperature inside the switch cabinet based on the temperature and humidity values ​​of the high temperature area at the current moment. Considering the uneven temperature distribution inside the switch cabinet, the present application focuses on whether condensed water will be generated in the low temperature area. The temperature of the low temperature area is mainly affected by the heat transfer effect between the high temperature area and the environment in which it is located. Therefore, the temperature range of the low temperature area is inferred based on the pre-constructed temperature distribution model, the temperature value of the high temperature area and the ambient temperature. Then, through trend analysis and dew point temperature comparison, it is determined whether the temperature in the low temperature area is likely to be lower than the dew point temperature. If there is a possibility, it is inferred that there is a risk of water vapor condensation. When there is a risk of water vapor condensation in the low temperature area of ​​the switch cabinet, the present application controls the dehumidification module to dehumidify the switch cabinet to avoid water vapor condensation. The present application fully considers the characteristics of uneven temperature inside the switch cabinet, determines the risk of water vapor condensation in the low temperature area of ​​the switch cabinet, and then controls the dehumidification module to dehumidify the air. Compared with the existing threshold control, while meeting the requirements of reducing energy consumption, it can also effectively avoid water vapor condensation in the low temperature area. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below in conjunction with the accompanying drawings and embodiments: Figure 1 It is a schematic diagram of the switch cabinet partition in an embodiment of the present application; Figure 2 is a structural schematic diagram of a humidity control system shown in an embodiment of the present application; Figure 3 is a flow chart of a humidity control method for a switch cabinet shown in an embodiment of the present application; Figure 4 It is a structural diagram of a humidity control system of a switch cabinet shown in one embodiment of the present application. DETAILED DESCRIPTION

[0019] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0020] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show the layers related to the present invention rather than being drawn according to the number, shape and size of the layers in actual implementation. In actual implementation, the type, quantity and proportion of each layer may be changed arbitrarily, and the layer layout may also be more complicated.

[0021] In the following description, numerous details are discussed to provide a more thorough explanation of embodiments of the present invention; however, it is apparent to one skilled in the art that embodiments of the present invention may be practiced without these specific details.

[0022] Figure 1 Schematic diagram of switch cabinet partition in one embodiment of the present application. Figure 1 As shown, the switch cabinets for humidity control in this application are mainly outdoor switch cabinets. Under outdoor conditions, the temperature distribution inside and outside the switch cabinet is uneven. Indoor switch cabinets have air conditioning systems, so the internal temperature is more balanced. Since outdoor switch cabinets are directly exposed to the natural environment, their temperature distribution will be affected by external weather conditions, and also depends on the heating conditions of internal electrical components and heat dissipation design. The following are examples of high temperature areas and low temperature areas in this application: (1) High temperature area Main busbar connection point: Even in cold weather, this is still a high temperature area because of the large amount of heat generated by the large current passing through.

[0023] Near circuit breakers, contactors and other high-power electrical components: These components will have a certain amount of energy loss converted into heat during operation, especially when carrying large currents or operating frequently, the temperature around them will still remain relatively high.

[0024] Transformer room: If the switch cabinet contains a small transformer, the heat generated by it during operation is enough to make this area a high temperature zone.

[0025] Cable entry and exit terminals: Especially when the cable carries a large current, the joints may become warm due to resistance heating.

[0026] Near heating devices: To prevent the impact of low temperature on electrical performance, some switchgear are equipped with heaters or temperature control systems, and the areas near these heating devices will maintain a higher temperature.

[0027] (2) Low temperature area Top and Near-Top Areas: During the winter, especially at night or on cloudy days, the top can become very cold due to sinking cold air and lack of direct sunlight.

[0028] Bottom and near the ground: Although the bottom is usually cooler because cold air is heavier and tends to sink, this effect is more pronounced in cold weather, especially if the ground is also cold.

[0029] Near vents: If you have a good ventilation system, the vents will bring in cool air from outside, making these places even cooler.

[0030] Leeward or sheltered areas: Although these areas are not subject to direct wind chill, they can become quite cold if they lack adequate heat sources (such as no electrical equipment or heating).

[0031] Locations away from major heat sources: For example, areas where low-power components such as auxiliary control circuits and signal devices are located may be very low in cold weather because they generate little heat and are away from major heat sources.

[0032] Standby equipment or lines in a non-operating state: Non-operating equipment does not generate additional heat, so in cold environments, the temperature of these parts may be close to or even lower than the external ambient temperature.

[0033] Figure 2 is a schematic diagram of the structure of a humidity control system shown in an embodiment of the present application, such as Figure 2 As shown, this application adopts the cloud + distributed controller method to control humidity. A distributed controller (such as a single-chip microcomputer, FPGA programmable control device, etc.) is built into each switch cabinet, and each distributed controller is connected to the cloud controller through the network. The basic data collection, big data model construction, and control instruction issuance in this application are all executed in the cloud server.

[0034] In addition, the present application adopts semiconductor refrigeration technology in the condensation module in the switch cabinet, which reduces the relative humidity in the cabinet by creating condensation conditions locally and directly discharges the condensed moisture. When the distributed control receives the control command from the cloud controller, the starter device draws the humid air in the switch cabinet into the dehumidification air duct under the action of the fan, and the water vapor in the air condenses into water after passing through the semiconductor refrigeration mechanism, and then is discharged from the cabinet through the water pipe.

[0035] By applying a DC power supply to the semiconductor refrigeration device, the cold end of the semiconductor can absorb heat from the outside world under the Peltier effect, so that the ambient temperature gradually decreases, while the hot end releases heat to the hot end. Under the action of the fan, the cooling effect is repeatedly generated, and the condensed water can be smoothly discharged from the switch cabinet to ensure that the air humidity in the enclosed space reaches the set value.

[0036] Figure 3 is a flow chart of a humidity control method for a switch cabinet shown in an embodiment of the present application, such as Figure 3 As shown, a humidity control method for a switch cabinet in this embodiment may include the following steps: S310, obtaining internal temperature values ​​and internal humidity values ​​at multiple time points in the switch cabinet; and obtaining the ambient temperature value of the environment in which the switch cabinet is located at the current time point and temperature prediction values ​​at multiple future time points, wherein the multiple time points include the current time point, and the internal temperature value is the temperature value of the high temperature area of ​​the switch cabinet; The existing switch cabinet monitoring system includes temperature sensors installed in high-temperature areas, such as temperature sensors installed in busbars, line bars, etc. This application only uses existing temperature and humidity sensors to collect the internal temperature and internal humidity values ​​of the high-temperature area, so it can save costs. In addition, when the air flows inside the switch cabinet, the air in the high-temperature area is more likely to produce condensed water when encountering the low-temperature area, especially when the temperature in the low-temperature area is lower than the dew point temperature. The air saturated with water vapor at the dew point temperature will condense water when encountering low temperatures. Therefore, it is safer to use the temperature and humidity in the high-temperature area to calculate the dew point temperature.

[0037] In addition, the environment where the switch cabinet is located will also affect the temperature of the low-temperature area, and thus determine the temperature of the low-temperature area. Therefore, this application obtains the current temperature of the environment where the switch cabinet is located and the predicted temperature at multiple time points in the future by setting a thermometer or checking the temperature measurement value of the weather station (depending on whether there is a heat source that affects the temperature nearby, if so, a thermometer needs to be set).

[0038] S320, calculating the dew point temperature inside the switch cabinet based on the internal temperature value and the internal humidity value at the current time point; and determining the temperature range of the low-temperature area in the switch cabinet based on the internal temperature value at the current time point and the ambient temperature value at the current time point and a pre-constructed temperature distribution model, wherein the temperature distribution model includes the temperature range of the low-temperature area corresponding to a plurality of internal and external temperature units, and each internal and external temperature unit includes an internal temperature value range and an ambient temperature value range; Among them, the dew point temperature The mathematical representation of is:

[0039]

[0040] In the formula, is the internal humidity value, is the internal temperature value, is an intermediate variable.

[0041] This application determines the temperature range of the low-temperature area in the switch cabinet based on a pre-built temperature distribution model, thereby determining whether the temperature of the low-temperature area in the switch cabinet will be lower than the dew point temperature. If it is lower, the air will not be able to accommodate the current content of water vapor when it is cooled, thereby condensing water droplets. Therefore, due to cost, wiring difficulties and electromagnetic interference, it is impossible to install temperature sensors in all low-temperature areas of the switch cabinet to directly collect temperature values. This application uses big data statistics to determine the temperature value of the low-temperature area.

[0042] Since different switch cabinet models have different internal structures, the distribution of high temperature areas and low temperature areas is also different. Therefore, the temperature distribution model in this application is only for the same type of switch cabinet. In addition, multiple temperature distribution models can be constructed for multiple types of switch cabinets, and the principles are the same.

[0043] In this embodiment, a temperature distribution model based on big data is constructed in the following manner, specifically including: (1) Acquiring a plurality of historical sample data, wherein the historical sample data includes an overall infrared thermal image of the switch cabinet, an ambient temperature value of the environment in which the switch cabinet is located, and an internal temperature value at the same time point; (2) reading the temperature value of one or more low-temperature areas from the overall infrared thermal image of the switch cabinet; In the basic data collection stage, staff or fixed infrared cameras are required to regularly capture infrared thermal images of the switch cabinet as a whole, so as to obtain the overall temperature distribution of the switch cabinet. The specific process includes: Get infrared thermal images: Use an infrared thermal imager to scan the target area (such as a switch cabinet) to ensure that all points of interest are captured. Save high-quality infrared images for subsequent analysis.

[0044] Import images into analysis software: Import the captured infrared images into professional analysis software provided by the thermal imager manufacturer, such as FLIR Tools, Testo IRSoft, etc. Confirm that the image timestamp, environmental conditions (such as humidity, wind speed, etc.) and other relevant parameters are correctly recorded, as this information is very important for accurate interpretation of the results.

[0045] Calibration and setup: If necessary, adjust emissivity, background temperature and other parameters according to actual conditions to ensure measurement accuracy. Different materials have different emissivities, and choosing the correct value can improve accuracy.

[0046] Select points or areas of interest: In the software interface, you can mark the specific location (point, line or surface) you want to measure by clicking or dragging the mouse. For multiple points, you can add marks one by one and give each mark a name or number for easy identification.

[0047] Read temperature data: The software automatically calculates and displays the temperature value of the selected point. You can view the temperature of a single point, or get statistical information such as the average temperature, maximum temperature, and minimum temperature of the entire area. Record the temperature data of each point for further analysis or report generation.

[0048] Here is an example: Assume that this application is to analyze the temperature distribution of different electrical components inside an outdoor switch cabinet: Preparation stage: A FLIR T-series thermal imaging camera was used to fully scan the switch cabinet and obtain clear infrared images.

[0049] Import and setup: Import the image into FLIR Tools software and confirm that all environmental parameters are set correctly, especially the emissivity of the metal surface is set correctly (for example, around 0.9).

[0050] Select the points: Decide to monitor several key locations: main busbar connection points, circuit breakers, transformer room, and bottom vents.

[0051] Markings were placed at these four locations and named "Busbar connection", "Circuit breaker", "Transformer" and "Vent" respectively.

[0052] Reading temperature: After software processing, we get the following temperature data: High temperature area: The temperature at the busbar connection is about 55°C; the temperature near the circuit breaker is about 48°C; the temperature in the transformer room is about 50°C; Low temperature area: The temperature at the bottom vent is close to the external ambient temperature, about 10°C.

[0053] It is worth noting that the temperature of the internal high temperature area can be measured using the readings from the infrared thermal image or the readings from the internal temperature and humidity sensor. If the two differ greatly, the sensor reading shall prevail.

[0054] (3) dividing the plurality of historical sample data based on the plurality of pre-divided internal temperature value ranges to obtain a plurality of data units; dividing each data unit based on the plurality of pre-divided ambient temperature value ranges to obtain a plurality of internal and external temperature units; and density clustering the plurality of historical sample data in the plurality of internal and external temperature units based on the temperature values ​​of the low temperature area to obtain a plurality of data clusters; After obtaining a large amount of basic data through step (2), the historical sample data can be divided. First, the multiple sample data are divided into multiple internal and external temperature units through multiple internal temperature value ranges and ambient temperature value ranges, and then the historical sample data in the multiple internal and external temperature units are density clustered. Since the temperature in the low temperature area is mainly affected by the internal temperature and the ambient temperature, the multiple data clusters obtained are generally a main data cluster and other abnormal data clusters with less data.

[0055] (4) taking a data cluster that meets a first target condition as a target cluster, wherein the first target condition includes: the number of historical sample data is greater than a preset number threshold, and the variance of the temperature values ​​of all low-temperature areas is less than a preset variance threshold; In order to retain the main data clusters and filter out interfering data, this application sets two screening conditions, namely, the amount of data is greater than the quantity threshold, and the variance is less than the preset variance threshold. In this way, the main data clusters with a large number and a dense distribution are screened out as reference data sets. For example: Internal temperature: 50℃-55℃; ambient temperature 0℃-5℃; reference data set {12.5℃, 10.2℃, 11.4℃....}.

[0056] (5) Calculate the mean temperature value of the low temperature area of ​​all historical sample data in the target cluster and standard deviation , and based on the mean of the temperature values and standard deviation Temperature range for building multiple target clusters ; In order to convert the discrete reference data set into a continuous range, this application uses the 3-times standard deviation principle to construct the temperature ranges of multiple target clusters. In a normal distribution (also called a Gaussian distribution or bell curve), approximately 99.73% of the data points will fall within plus or minus 3 standard deviations of the mean. This is based on the "68-95-99.7 rule" or "rule of thumb" in statistics.

[0057] (6) A temperature distribution model is constructed based on the multiple internal and external temperature units and the temperature ranges of the low temperature areas corresponding to the multiple internal and external temperature units.

[0058] After obtaining the temperature distribution model, the temperature range of all low-temperature areas can be roughly obtained based on the current internal temperature of the switch cabinet and the ambient temperature.

[0059] S330, determining the temperature difference change trend between the high temperature area and the low temperature area in the switch cabinet based on the internal temperature values ​​at multiple time points and the temperature prediction values ​​at multiple future time points, and performing water vapor condensation risk determination based on the dew point temperature, the temperature range of the low temperature area and the temperature difference change trend; The logic of risk determination is that if the temperature of the low-temperature area at the current time point may be lower than the dew point temperature, or if the temperature of the low-temperature area at the current time point has a trend of being lower than the dew point temperature, then it is determined that there is a risk of water vapor condensation. At this time, the cloud server sends a control instruction to control the dehumidification module.

[0060] Therefore, before making a judgment, it is necessary to analyze the temperature difference change trend between the high-temperature area and the low-temperature area in the switch cabinet. When the external conditions are cold, if the temperature difference becomes larger, the low-temperature area will be closer to the external temperature, and the temperature in the low-temperature area will drop further, and it is more likely to drop to the dew point temperature, and the risk of condensation water will be greater.

[0061] The determination process of temperature difference trend includes: S3301, calculating the temperature trend in the switch cabinet based on the internal temperature values ​​at multiple time points, and determining the temperature trend of the ambient temperature based on the temperature prediction values ​​at multiple future time points, wherein the temperature trend includes an upward trend, a downward trend, and a trend without unidirectional change; Through data analysis, trend analysis is performed on the existing internal temperature values ​​at multiple time points, and trend analysis is performed on the temperature forecast values ​​at multiple future time points. The analysis process includes: (1) mapping the temperature values ​​at multiple time points into a two-dimensional coordinate system, wherein the horizontal axis of the two-dimensional coordinate system is the time axis, and the vertical axis of the two-dimensional coordinate system is the temperature axis, wherein the temperature values ​​are internal temperature values ​​or temperature prediction values; (2) Slide along the time axis based on the pre-built sliding window, and calculate the average temperature value of all time points in the sliding window at each sliding. ,in, Indicates the sliding order; (3) When any two adjacent average values ​​satisfy: , it is determined that the temperature in the switch cabinet is decreasing; when any two adjacent average values ​​satisfy: , it is determined that the temperature in the switch cabinet is on an upward trend; otherwise, it is determined that there is no unidirectional change trend.

[0062] In order to ignore the trend analysis impact caused by single data fluctuations, this application uses a sliding window to analyze trends. Data is processed and analyzed by moving a fixed-size time window or data point number window on a continuous data stream. The sliding window can effectively smooth short-term random fluctuations, making long-term trends more obvious. In addition, compared to simply taking a period of historical data as a reference, the sliding window allows for a faster response to new data points. Because each time new data arrives, the window slides forward, discarding the oldest data point and adding the latest data point, which helps reduce lags in the analysis results.

[0063] S3302, when the temperature trend in the switch cabinet and the ambient temperature is an upward trend or a downward trend, calculate the change amount; In many cases, a drop in ambient temperature will also cause the temperature inside the switch cabinet to drop, but because the electrical components inside the switch cabinet are working, the drop rate will be slower. Therefore, if the change trends of the ambient temperature and the switch cabinet are the same, it is still necessary to calculate the change to find out whether the temperature difference has increased.

[0064] S3303: When one of the second target conditions is met, it is predicted that the temperature difference between the high temperature area and the low temperature area in the switch cabinet has a tendency to increase, wherein the second target condition includes the following four situations: (1) The switch cabinet is on an upward trend, while the ambient temperature is on a downward trend; for example, the load of components in the switch cabinet increases, but the ambient temperature continues to drop, which will cause the temperature difference to gradually increase; (2) The switch cabinet is on an upward trend, and the ambient temperature has no unidirectional change trend; for example, the load of the components in the switch cabinet increases, but the ambient temperature remains stable, which will cause the temperature difference to gradually increase; (3) The switch cabinet temperature and the ambient temperature are both on an upward trend, and the change in the switch cabinet is greater than the change in the environment. For example, a drop in ambient temperature will also cause the temperature inside the switch cabinet to drop, but because the electrical components in the switch cabinet are working, the drop rate will be slower, causing the temperature difference to gradually increase.

[0065] (4) The switch cabinet has no unidirectional change trend, and the ambient temperature is on a downward trend. For example, the switch cabinet maintains a stable internal temperature due to the continuous operation of the components. However, the external ambient temperature gradually decreases, which will cause the temperature difference to gradually increase.

[0066] In addition, there are many situations where the temperature difference gradually decreases and the temperature difference remains constant. In this application, we only need to focus on the situation that causes the temperature difference between the low temperature area and the high temperature area to gradually increase, so other situations will not be expanded here.

[0067] In this application, the process of risk determination based on the above temperature difference change is as follows: The lower limit of the temperature range of the low temperature region is With the dew point temperature For comparison; the lower limit of the temperature range in the low temperature area is The lowest possible temperature, since the main purpose of this application is to prevent the condensation of water vapor, and the lower limit of the temperature range in the low temperature area As a comparison benchmark.

[0068] If at the current time point: the lowest temperature that may occur in the low temperature area is lower than the current dew point temperature, that is, When the air in the high-temperature area encounters the low-temperature area, the air will be cooled, resulting in the air being oversaturated with water, and the water vapor will condense into water droplets. Therefore, it is determined that there is a risk of water vapor condensation at the current time point; If the current time point does not meet the above conditions, but the lowest temperature that may occur in the low-temperature area at the current moment is close to the dew point temperature, and the temperature difference trend is gradually increasing, that is, when the above conditions are met, , , and the temperature difference between the high temperature area and the low temperature area in the switch cabinet tends to increase; the low temperature area is more susceptible to the external temperature, so the larger temperature difference will cause the temperature of the low temperature area to gradually approach and fall below the dew point temperature, which will lead to condensation of water vapor. Therefore, in this case, it is determined that the switch cabinet has the risk of condensation of water vapor at a future time point. is the set temperature difference threshold.

[0069] S340: When there is a risk of water vapor condensation in the switch cabinet, control a dehumidification module in the switch cabinet to dehumidify the switch cabinet.

[0070] When a risk determination result is obtained, an alarm message is sent to relevant staff and can also be recorded in the cloud. In addition, this application uses the following process for dehumidification to save energy consumption, including: S1, controlling the dehumidification module to dehumidify the air in the switch cabinet at rated power for a target time, and reacquiring the internal temperature value and the internal humidity value after dehumidification; The target duration can be 5 minutes or 10 minutes, which can be set according to your needs. After dehumidification, obtain the temperature and humidity of the high temperature area again.

[0071] S2, updating the dew point temperature based on the re-acquired internal temperature value and internal humidity value; the calculation formula may refer to the above description.

[0072] S3, based on the updated dew point temperature, the temperature range of the low-temperature area and the temperature difference change trend, determine whether there is a risk of water vapor condensation in the switch cabinet. If there is a risk of water vapor condensation, return to step S1 until there is no risk of water vapor condensation; if there is no risk of water vapor condensation, control the dehumidification module to stop dehumidification.

[0073] If there is still a risk of condensation in combination with the updated dew point temperature, the next dehumidification cycle is entered, and the process is cycled to ensure that there is no risk of condensation in the switch cabinet. This process requires good sealing of the switch cabinet. If the sealing is poor, the temperature of the low-temperature area can be increased by setting a heating module, and the risk assessment can be repeated in the same way.

[0074] After the dehumidification process, if there is no risk of water vapor condensation, the dehumidification module is stopped immediately to save energy. A drainage hole is provided at the bottom of the dehumidification module, and the drainage hole discharges the condensed water out of the switch cabinet through a pipe.

[0075] A humidity control method for a switch cabinet of the present invention obtains temperature values ​​and humidity values ​​at multiple time points inside the switch cabinet, and calculates the dew point temperature in the switch cabinet based on the temperature value and humidity value of the high temperature area at the current moment. Considering the uneven temperature distribution inside the switch cabinet, the present application focuses on whether condensed water will be generated in the low temperature area. The temperature of the low temperature area is mainly affected by the heat transfer effect between the high temperature area and the environment. Therefore, the temperature range of the low temperature area is inferred based on the pre-constructed temperature distribution model, the temperature value of the high temperature area and the ambient temperature. Then, through trend analysis and dew point temperature comparison, it is determined whether the temperature in the low temperature area is likely to be lower than the dew point temperature. If there is a possibility, it is inferred that there is a risk of water vapor condensation. When there is a risk of water vapor condensation in the low temperature area of ​​the switch cabinet, the present application controls the dehumidification module to dehumidify the switch cabinet to avoid water vapor condensation. The present application fully considers the characteristics of uneven temperature inside the switch cabinet, determines the risk of water vapor condensation in the low temperature area of ​​the switch cabinet, and then controls the dehumidification module to dehumidify the air. Compared with the existing threshold control, while meeting the requirements of reducing energy consumption, it can also effectively avoid water vapor condensation in the low temperature area.

[0076] like Figure 4 As shown, the present application also provides a humidity control system for a switch cabinet, comprising: An acquisition module is used to acquire the internal temperature value and internal humidity value at multiple time points in the switch cabinet; and to acquire the ambient temperature value of the environment in which the switch cabinet is located at the current time point and the temperature prediction values ​​at multiple future time points, wherein the multiple time points include the current time point, and the internal temperature value is the temperature value of the high-temperature area of ​​the switch cabinet, and the high-temperature area includes the area where the main busbar connection point is located, the area where the circuit breaker is located, the area where the contactor and other high-power electrical components are located, the transformer room, the cable inlet and outlet terminals, and the area where the heating device is located; A temperature analysis module is used to calculate the dew point temperature inside the switch cabinet based on the internal temperature value and the internal humidity value at the current time point; and determine the temperature range of the low-temperature area in the switch cabinet based on the internal temperature value at the current time point and the ambient temperature value at the current time point and a pre-constructed temperature distribution model, wherein the temperature distribution model includes the temperature range of the low-temperature area corresponding to a plurality of internal and external temperature units, each of which includes an internal temperature value range and an ambient temperature value range, and the low-temperature area includes the top and the area close to the top plate, the bottom and the partial area close to the ground, the area where the vents are located, the leeward side or the shielded area, the area away from the main heat source, and the standby equipment or line area in a non-working state; A risk determination module, for determining the temperature difference variation trend between the high temperature area and the low temperature area in the switch cabinet based on the internal temperature values ​​at multiple time points and the temperature prediction values ​​at multiple future time points, and for performing water vapor condensation risk determination based on the dew point temperature, the temperature range of the low temperature area and the temperature difference variation trend; The dehumidification control module is used to control the dehumidification module in the switch cabinet to dehumidify the switch cabinet when there is a risk of water vapor condensation in the switch cabinet.

[0077] A humidity control system for a switch cabinet of the present invention obtains temperature values ​​and humidity values ​​at multiple time points inside the switch cabinet, and calculates the dew point temperature inside the switch cabinet based on the temperature value and humidity value of the high temperature area at the current moment. Considering the uneven temperature distribution inside the switch cabinet, the present application focuses on whether condensed water will be generated in the low temperature area. The temperature of the low temperature area is mainly affected by the heat transfer effect between the high temperature area and the environment in which it is located. Therefore, the temperature range of the low temperature area is inferred based on the pre-constructed temperature distribution model, the temperature value of the high temperature area and the ambient temperature. Then, through trend analysis and dew point temperature comparison, it is determined whether the temperature in the low temperature area is likely to be lower than the dew point temperature. If there is a possibility, it is inferred that there is a risk of water vapor condensation. When there is a risk of water vapor condensation in the low temperature area of ​​the switch cabinet, the present application controls the dehumidification module to dehumidify the switch cabinet to avoid water vapor condensation. The present application fully considers the characteristics of uneven temperature inside the switch cabinet, determines the risk of water vapor condensation in the low temperature area of ​​the switch cabinet, and then controls the dehumidification module to dehumidify the air. Compared with the existing threshold control, while meeting the requirements of reducing energy consumption, it can also effectively avoid water vapor condensation in the low temperature area.

[0078] This embodiment also provides an electronic terminal, including: a processor and a memory; The memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the terminal executes any one of the methods in this embodiment.

[0079] The computer-readable storage medium in this embodiment can be understood by ordinary technicians in this field: all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to the computer program. The aforementioned computer program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other media that can store program codes.

[0080] The electronic terminal provided in this embodiment includes a processor, a memory, a transceiver and a communication interface. The memory and the communication interface are connected to the processor and the transceiver and complete communication with each other. The memory is used to store computer programs, the communication interface is used to communicate, and the processor and the transceiver are used to run computer programs so that the electronic terminal executes each step of the above method.

[0081] In this embodiment, the memory may include a random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0082] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0083] In the above-mentioned embodiments, although the present invention has been described in conjunction with the specific embodiments of the present invention, many replacements, modifications and variations of these embodiments will be apparent to those skilled in the art according to the foregoing description. The embodiments of the present invention are intended to cover all such replacements, modifications and variations falling within the broad scope of the appended claims.

[0084] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A humidity control method for a switch cabinet, characterized in that: Includes steps: Obtain the internal temperature value and internal humidity value at multiple time points in the switch cabinet; and obtain the ambient temperature value of the environment where the switch cabinet is located at the current time point and the temperature prediction values ​​at multiple future time points, wherein the multiple time points include the current time point, and the internal temperature value is the temperature value of the high-temperature area of ​​the switch cabinet, and the high-temperature area includes the area where the main busbar connection point is located, the area where the circuit breaker is located, the area where the contactor and other high-power electrical components are located, the transformer room, the cable inlet and outlet terminals, and the area where the heating device is located; The dew point temperature inside the switch cabinet is calculated based on the internal temperature value and the internal humidity value at the current time point; and the temperature range of the low-temperature area in the switch cabinet is determined based on the internal temperature value at the current time point, the ambient temperature value at the current time point and a pre-constructed temperature distribution model, wherein the temperature distribution model includes the temperature range of the low-temperature area corresponding to a plurality of internal and external temperature units, each internal and external temperature unit includes an internal temperature value range and an ambient temperature value range, and the low-temperature area includes the top and the area close to the top plate, the bottom and part of the area close to the ground, the area where the vents are located, the leeward side or the shielded area, the area away from the main heat source, and the standby equipment or line area in a non-working state; Determine the temperature difference change trend between the high temperature area and the low temperature area in the switch cabinet based on the internal temperature values ​​at multiple time points and the temperature prediction values ​​at multiple future time points, and make a water vapor condensation risk determination based on the dew point temperature, the temperature range of the low temperature area and the temperature difference change trend; When there is a risk of water vapor condensation in the switch cabinet, the dehumidification module in the switch cabinet is controlled to dehumidify the switch cabinet.

2. A humidity control method for a switch cabinet according to claim 1, characterized in that: Controlling the dehumidification module in the switch cabinet to dehumidify the switch cabinet includes: S1, controlling the dehumidification module to dehumidify the air in the switch cabinet at rated power for a target time, and reacquiring the internal temperature value and the internal humidity value after dehumidification; S2, updating the dew point temperature based on the re-acquired internal temperature value and internal humidity value; S3, based on the updated dew point temperature, the temperature range of the low-temperature area and the temperature difference change trend, determine whether there is a risk of water vapor condensation in the switch cabinet. If there is a risk of water vapor condensation, return to step S1 until there is no risk of water vapor condensation; if there is no risk of water vapor condensation, control the dehumidification module to stop dehumidification.

3. A humidity control method for a switch cabinet according to claim 2, characterized in that: The dew point temperature The mathematical representation of is: In the formula, is the internal humidity value, is the internal temperature value, is an intermediate variable.

4. A humidity control method for a switch cabinet according to claim 1, characterized in that: The process of constructing the temperature distribution model includes: Acquire a plurality of historical sample data, wherein the historical sample data includes an overall infrared thermal image of the switch cabinet, an ambient temperature value of an environment where the switch cabinet is located, and an internal temperature value at the same time point; Reading the temperature value of one or more low-temperature areas from the overall infrared thermal image of the switch cabinet; Dividing multiple historical sample data based on multiple pre-divided internal temperature value ranges to obtain multiple data units; and dividing each data unit based on multiple pre-divided ambient temperature value ranges to obtain multiple internal and external temperature units; and density clustering multiple historical sample data in the multiple internal and external temperature units based on the temperature value of the low temperature area to obtain multiple data clusters; The data cluster that meets the first target condition is used as the target cluster, wherein the first target condition includes: the number of historical sample data is greater than a preset number threshold, and the variance of the temperature values ​​of all low temperature areas is less than a preset variance threshold; Calculate the mean temperature value of the low temperature area of ​​all historical sample data in the target cluster and standard deviation , and based on the mean of the temperature values and standard deviation Temperature range for building multiple target clusters ; A temperature distribution model is constructed based on a plurality of internal and external temperature units and temperature ranges of low temperature areas corresponding to the plurality of internal and external temperature units.

5. The humidity control method of a switch cabinet according to claim 1, characterized in that: Based on the internal temperature values ​​at multiple time points and the temperature prediction values ​​at multiple future time points, the temperature difference trend between the high temperature area and the low temperature area in the switch cabinet is determined, including: Calculating the temperature trend in the switch cabinet based on the internal temperature values ​​at multiple time points, and determining the temperature trend of the ambient temperature based on the temperature prediction values ​​at multiple future time points, wherein the temperature trend includes an upward trend, a downward trend, and a trend without unidirectional change; When the temperature trend in the switch cabinet and the ambient temperature is an upward trend or a downward trend, calculate the change amount; When one of the second target conditions is met, it is predicted that the temperature difference between the high-temperature area and the low-temperature area in the switch cabinet has a tendency to increase, wherein the second target condition includes: the switch cabinet is on an upward trend and the ambient temperature is on a downward trend; the switch cabinet is on an upward trend and the ambient temperature has no unidirectional change trend; the switch cabinet is on an upward trend and the ambient temperature is on an upward trend, and the change in the switch cabinet is greater than the change in the environment; the switch cabinet has no unidirectional change trend and the ambient temperature has a downward trend.

6. A humidity control method for a switch cabinet according to claim 5, characterized in that: The process of determining the temperature trend includes: Mapping the temperature values ​​at multiple time points into a two-dimensional coordinate system, wherein the horizontal axis of the two-dimensional coordinate system is the time axis, the vertical axis of the two-dimensional coordinate system is the temperature axis, and the temperature values ​​are internal temperature values ​​or temperature prediction values; Slide along the time axis based on the pre-built sliding window, and calculate the average temperature value of all time points in the sliding window at each sliding. ,in, Indicates the sliding order; When any two adjacent average values ​​satisfy: , it is determined that the temperature in the switch cabinet is decreasing; when any two adjacent average values ​​satisfy: , it is determined that the temperature in the switch cabinet is on an upward trend; otherwise, it is determined that there is no unidirectional change trend.

7. A humidity control method for a switch cabinet according to claim 5, characterized in that: The water vapor condensation risk is determined based on the dew point temperature, the temperature range of the low temperature area, and the temperature difference change trend, including: The lower limit of the temperature range of the low temperature region is With the dew point temperature Make a comparison; exist When , it is determined that there is a risk of water vapor condensation at the current time point; when , , and when the temperature difference between the high temperature area and the low temperature area in the switch cabinet tends to increase, it is determined that the switch cabinet has a risk of water vapor condensation at a future time point, among which, is the set temperature difference threshold.

8. A humidity control method for a switch cabinet according to claim 2, characterized in that: The dehumidification module is a semiconductor cooling module. A drainage hole is provided at the bottom of the dehumidification module. The drainage hole discharges condensed water out of the switch cabinet through a pipeline.

9. A humidity control method for a switch cabinet according to claim 1, characterized in that: Also includes: When there is a risk of condensation in the switch cabinet, an alarm message is sent to the target object.

10. A humidity control system for a switch cabinet, characterized in that: include: An acquisition module is used to obtain internal temperature values ​​and internal humidity values ​​at multiple time points in the switch cabinet; and obtaining the ambient temperature value of the environment in which the switch cabinet is located at the current time point and the temperature prediction values ​​at multiple future time points, wherein the multiple time points include the current time point, and the internal temperature value is the temperature value of the high temperature area of ​​the switch cabinet, and the high temperature area includes the area where the main busbar connection point is located, the area where the circuit breaker is located, the area where the contactor and other high-power electrical components are located, the transformer room, the cable inlet and outlet terminals, and the area where the heating device is located; A temperature analysis module is used to calculate the dew point temperature inside the switch cabinet based on the internal temperature value and the internal humidity value at the current time point; and determine the temperature range of the low-temperature area in the switch cabinet based on the internal temperature value at the current time point and the ambient temperature value at the current time point and a pre-constructed temperature distribution model, wherein the temperature distribution model includes the temperature range of the low-temperature area corresponding to a plurality of internal and external temperature units, each of which includes an internal temperature value range and an ambient temperature value range, and the low-temperature area includes the top and the area close to the top plate, the bottom and the partial area close to the ground, the area where the vents are located, the leeward side or the shielded area, the area away from the main heat source, and the standby equipment or line area in a non-working state; A risk determination module, for determining the temperature difference variation trend between the high temperature area and the low temperature area in the switch cabinet based on the internal temperature values ​​at multiple time points and the temperature prediction values ​​at multiple future time points, and for performing water vapor condensation risk determination based on the dew point temperature, the temperature range of the low temperature area and the temperature difference variation trend; The dehumidification control module is used to control the dehumidification module in the switch cabinet to dehumidify the switch cabinet when there is a risk of water vapor condensation in the switch cabinet.

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