A safety protection device for a switchgear cabinet and a switchgear cabinet

Abstract

The present invention relates to the technical field of switch cabinets, and particularly relates to a switch cabinet safety protection device and a switch cabinet. The switch cabinet safety protection device includes: a temperature sensing module, which is used to sense the temperature inside and outside the switch cabinet; an air flow driving module, which is used to drive air into the switch cabinet; a refrigeration module, which is used to refrigerate the air inside the switch cabinet; and a control module, which is electrically connected to the temperature sensing module, the humidity sensing module, the air flow driving module, and the refrigeration module. The present invention condenses the moisture in the air through refrigeration, thereby controlling the humidity of the incoming air. While achieving temperature control, it meets the humidity requirements. It can prevent the moisture in the air from being brought into the switch cabinet, causing damage to electrical components when the humidity is too high, greatly protecting the electrical components, slowing down corrosion in a humid environment, extending the service life of the electrical components, and at the same time increasing the use safety of the switch cabinet.

Description

Technical Field

[0001] The present invention relates to the technical field of switch cabinets, and particularly relates to a safety protection device for a switch cabinet and a switch cabinet. Background Art

[0002] A switch cabinet is a switching device used in a high-voltage power system for current switching, isolation, and control. It usually consists of one or more circuit breakers and can operate on a circuit without power outage. Switch cabinets are widely used in power plants, transmission lines, substations, etc., providing an important guarantee for the stable operation of the power system. The main components of a switch cabinet include: a base, which is installed on the ground to support the entire switch cabinet and improve its stability; compartments, which divide the interior of the switch cabinet into different areas to achieve functions such as current isolation and control; a circuit breaker, which is responsible for cutting off and connecting the circuit and is the core part of the switch cabinet; a grounding system, which is used to ensure the safety and reliability of the switch cabinet and prevent electric shock and other accidents; sensors and actuators, which are used to monitor and control the working state of the switch cabinet and achieve automation functions; a communication interface, which facilitates remote monitoring and management of the switch cabinet; and an arc extinguishing device, which is used to absorb and disperse arcs and prevent the spread of arcs to other areas. According to different voltage levels and uses, switch cabinets can be divided into various types, such as conventional switch cabinets, outdoor switch cabinets, indoor switch cabinets, gas-insulated switch cabinets, vacuum switch cabinets, SF6 gas-insulated switch cabinets, etc. Each type of switch cabinet has its own characteristics and application ranges. During the use of a switch cabinet, attention needs to be paid to maintenance and upkeep to ensure its reliability and safety. Regularly checking and repairing the switch cabinet and promptly replacing damaged parts can effectively extend the service life of the switch cabinet.

[0003] Electrical components will be affected to a certain extent during use, and humidity is an important factor among them. Too high or too low humidity may cause electrical components to malfunction or their performance to decline. The following lists the impacts of humidity changes on some common electrical components: Power supply components: Components such as transformers and rectifier diodes in the power supply assembly are prone to corrosion, leakage, etc. in a humid environment, which may lead to unstable power supply or electrical appliance damage. Switches and relays: Electrical components such as switches and relays may experience rust, inability to open / close tightly, etc. when in a humid environment for a long time. Cables and plugs: The insulation layers of cables and plugs are prone to damage when in long-term contact with a humid environment, thus triggering safety hazards such as electric shock. Circuit protection: When the humidity is high, it is easy to cause the circuit protection components (such as fuses) to blow, affecting normal power supply; when the humidity is low, it may cause circuit short circuits, triggering accidents such as fires. Sensors: The accuracy and balance of humidity sensors will be affected by humidity fluctuations, such as temperature compensation errors, output signal distortion, etc. To address the impacts of humidity on electrical components, the following measures can be taken for prevention and treatment: Use moisture-proof packaging materials to protect electrical products from humid environments. Maintain proper ventilation during storage and transportation to reduce relative humidity. Provide desiccants for key equipment and components to absorb excess moisture. For damaged electrical components, replace and repair them in a timely manner to prevent further damage caused by the deterioration of the humid environment. Regularly check the humidity conditions of electrical equipment and systems, and detect and handle abnormalities in a timely manner.

[0004] Existing switchgear cabinets do not have a protection device that combines temperature reduction and humidity reduction, resulting in great protection difficulty. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a switchgear cabinet safety protection device for intelligently controlling the temperature and humidity inside the switchgear cabinet. The switchgear cabinet safety protection device may include:

[0006] A temperature sensing module for sensing the temperature inside and outside the switchgear cabinet. The temperature sensing module is an electronic device used to measure and monitor temperature, which can convert the change in ambient temperature into a readable value and output it to the user.

[0007] A humidity sensing module for sensing the humidity inside and outside the switchgear cabinet. The humidity sensing module is an electronic device used to detect the ambient humidity and convert it into a digital signal for output. The humidity sensing module mainly measures the humidity in the environment through various internal humidity sensors.

[0008] An air flow driving module for driving air into the switchgear cabinet, forming an air flow inside the switchgear cabinet, and finally discharging the air from the switchgear cabinet. In the design of the switchgear cabinet, generally, air inlet and outlet openings are provided on opposite sides of the switchgear cabinet.

[0009] The refrigeration module is used to cool the air inside the switchgear. As mentioned above, when the temperature difference between the inside and outside of the switchgear is small, the effect of this simple cooling method is poor and often fails to achieve the cooling purpose. At this time, the refrigeration module is needed for assistance.

[0010] The control module is electrically connected to the temperature sensing module, humidity sensing module, air flow driving module and refrigeration module, and is used to receive the temperature and humidity values sensed by the temperature sensing module and humidity sensing module, and is used to control the air flow driving module to drive the air flow and the refrigeration module to refrigerate. Obtain the internal temperature T of the switchgear 1 and the external temperature T 2 , the internal humidity AH of the switchgear 1 and the external humidity AH 2 , judge whether the internal temperature T 1 is greater than a preset working temperature T 1 标 , if not, then cooling is not required; if so, then judge whether the external temperature T 2 is less than a preset cooling temperature T 2 标 , if not, then turn on the refrigeration module to cool the inside of the switchgear. If so, then judge the RH 1 标 at the working temperature T 2 is greater than a preset RH 2 标 , if not, then normally control the air flow driving module to drive the air for cooling, if so, then start the air flow driving module and the refrigeration module, the air flow driving module drives the air to enter, and the refrigeration module cools the entering air to the cooling temperature T0.

[0011] Preferably: The preset working temperature T 1 标 can be the maximum temperature for the normal use of the electrical components inside the switchgear. The specific obtaining method can include: obtaining the upper limit temperature of each electrical component inside the switchgear, and then using the minimum upper limit temperature as the working temperature T 1 标 . This method of obtaining the working temperature T 1 标 is relatively simple, and can ensure that each electrical component can work within the normal temperature, ensuring its use safety. However, this requires frequent cooling, and the cooling threshold is relatively low, so a large amount of energy is needed for maintenance, and the maintenance cost is relatively high.

[0012] Preferably: The preset working temperature T 1 标It can also be calculated according to the tolerance of each electrical component. The specific calculation methods include: obtaining the information data of various electrical components and their upper limit operating temperatures. Here, the upper limit operating temperature does not mean that the electrical component will be damaged when the temperature exceeds this value, but that when operating at this temperature, it will cause damage to the electrical component, and its loss is greater than the normal range. The specific temperature varies depending on the type, material, process, etc. of the electrical component. Then, sort them in ascending order according to the upper limit operating temperature, and calculate the optimized temperature T' for the electrical tolerance in the switchgear cabinet, and use the optimized temperature T' for electrical tolerance as the operating temperature T 1 标 。

[0013] Preferably, the calculation method of the optimized temperature for electrical tolerance may include: calculating the tolerance factor t of the electrical component, and the tolerance factor , where i and j are the sorting numbers of the electrical components, and t i is the tolerance coefficient of the electrical component numbered i, and I is the total number of types of electrical components. j≥i; i, j = 1, 2,..., I; First, let j = 1 and calculate the tolerance factor , then determine whether the tolerance factor is greater than a preset standard factor t 标 . If so, it is determined that the upper limit operating temperature of the electrical component corresponding to j is the optimized temperature T' for electrical tolerance. If not, calculate the tolerance factor for j + 1 and repeat the above steps.

[0014] Preferably, the tolerance coefficient t i can be obtained based on experience. Of course, it can also be obtained through calculation. The specific obtaining method may include the tolerance coefficient , where n is the tolerance factor number, f n is the tolerance factor value of the tolerance factor numbered n, and N is the total number of tolerance factors. n = 1, 2,..., N. The tolerance factor is the value corresponding to the corresponding tolerance factor.

[0015] Preferably, the tolerance factors may include quantity, importance degree of the electrical component, and damage degree of the electrical component, which can be included in the information data of the electrical component. The tolerance factor of the quantity can be the quotient of the actual quantity and the standard quantity. The tolerance factor of the importance degree of the electrical component can be a manually set level and assigned values according to the level. The tolerance factor of the damage degree of the electrical component can be the damage level at the current upper limit temperature, which can be manually set. Of course, we can also set it to a fixed value, but the calculation error is relatively large. The cooling threshold set by this method is more reasonable, can perform intelligent analysis on the performance of each electrical component, set appropriate cooling thresholds, achieve component protection and reduce energy consumption, and achieve an optimized balance.

[0016] Preferably, the cooling temperature T 2 标The specific value can be calculated according to the working temperature T 1 标 and the cooling temperature difference. Specifically, it can be the cooling temperature T 2 标 =T 1 标 -ΔT, where ΔT is the standard temperature reduction difference and can be set according to specific circumstances, generally 10 - 30°C.

[0017] Preferably: the working temperature T 1 标 under , where AH S is the saturated water vapor density at the working temperature T 1 标 under.

[0018] Preferably: the cooling temperature T0 can be set artificially according to experience, and of course it can also be obtained by calculation. The specific obtaining method can include: calculating the working upper limit absolute humidity AH 2 ’, the working upper limit absolute humidity , we work at the preset RH 1 标 humidity under the working temperature T 2 标 to meet the working of electrical components at the critical temperature and humidity, and can protect electrical components to the greatest extent. Calculate the saturated water vapor density AHS’ after cooling through the working upper limit absolute humidity, and then look up the pre-prepared saturated water vapor density - temperature information table according to the saturated water vapor density AHS’ to obtain the cooling temperature T0. The saturated water vapor density - temperature information table is prior art and will not be elaborated here specifically.

[0019] Preferably: the saturated water vapor density after cooling , where ΔAH is the deviation water vapor density. Theoretically, if the temperature of the incoming air is uniform and can be cooled to the cooling temperature, its value is zero. In the actual operation process, its value is generally 0.2 - 5 g / m 3 , of course, this value is not universal and specifically needs to be determined according to equipment parameters, the volume of the switch cabinet, temperature difference, air flow drive module, etc., and will not be elaborated here specifically. By using this method to cool and dehumidify the switch cabinet, it can avoid the electrical components in the switch cabinet from working in an overheated and overhumid environment, and while ensuring the normal operation of the electrical appliances, it can save energy to the greatest extent and reduce energy consumption.

[0020] The present invention also provides a switch cabinet, which includes a cabinet body and the above-mentioned switch cabinet safety protection device. An air inlet and an air outlet are provided on the cabinet body, and the air flow driving module is installed at the position of the air inlet or the air outlet. The refrigeration module is installed on the inner wall of the cabinet body at the position of the air inlet, and the control module can be set on the cabinet body or can be remotely controlled, which is specifically set according to actual needs. Obtain the internal temperature T of the switch cabinet 1 and the external temperature T 2 , the internal humidity AH of the switch cabinet 1 and the external humidity AH 2 , judge whether the internal temperature T 1 is greater than a preset working temperature T 1 标 . If not, cooling is not required; if so, judge whether the external temperature T 2 is less than a preset cooling temperature T 2 标 . If not, turn on the refrigeration module to cool the inside of the switch cabinet. If so, judge the RH 1 标 at the working temperature T 2 is whether greater than a preset RH 2 标 . If not, normally control the air flow driving module to drive the air for cooling. If so, start the air flow driving module and the refrigeration module. The air flow driving module drives the air to enter, and the refrigeration module cools the entering air to the cooling temperature T0. In this way, it is possible to avoid bringing moisture in the air into the switch cabinet, avoid damage to electrical components when the humidity is too high, greatly protect electrical components, slow down corrosion in a humid environment, extend the service life of electrical components, and at the same time increase the use safety of the switch cabinet.

[0021] Preferably: a condensation water tank is installed on the inner side wall of the cabinet body. The condensation water tank is located below the refrigeration module. The condensation water tank is used to receive the water droplets condensed by the refrigeration of the refrigeration module. A drain pipe is fixedly connected to the bottom of the condensation water tank. The drain pipe can extend out of the cabinet body. The condensed water droplets enter the condensation water tank and then are discharged from the cabinet body through the drain pipe.

[0022] Preferably: hinge leaves can be provided at the positions of the air inlet and the air outlet of the cabinet body. The hinge leaves on the air inlet can limit the air to enter only when driven by the air flow driving module. When there is air flow, the air flow will drive the blades on the hinge leaves to rotate, and there will be gaps for the air flow to pass through between the rotating blades, so as to facilitate the entry of air. When the air flow driving module stops driving, the air flow disappears. Under the action of gravity, the blades of the hinge leaves contact each other, and the gaps for the air flow to pass through disappear, separating the switch cabinet from the external environment to form a sealed space, so that the external humidity can be prevented from entering the switch cabinet.

[0023] Technical effects and advantages of the present invention: By refrigerating to condense the moisture in the air, the present invention controls the humidity of the incoming air, achieving temperature control while meeting the humidity requirement. It can prevent the moisture in the air from entering the switch cabinet, avoid damage to electrical components when the humidity is too high, greatly protect the electrical components, slow down corrosion in a humid environment, extend the service life of the electrical components, and increase the use safety of the switch cabinet. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural block diagram of a switch cabinet safety protection device proposed by the present invention;

[0025] Figure 2 It is a control flow chart of the control module in a switch cabinet safety protection device proposed by the present invention;

[0026] Figure 3 It is a flow chart of the calculation method for the optimized temperature of electrical tolerance of the control module in a switch cabinet safety protection device proposed by the present invention;

[0027] Figure 4 It is a structural diagram of the air inlet of a switch cabinet proposed by the present invention;

[0028] Description of reference numerals: Cabinet 1, condenser 2, hinge 3, condensate tank 4, drain pipe 5, air inlet 6. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments. The embodiments of the present invention are given for purposes of illustration and description, and are not exhaustive or limit the present invention to the disclosed form. Many modifications and variations are obvious to those of ordinary skill in the art. The embodiments are selected and described to better illustrate the principles and practical applications of the present invention, and enable those of ordinary skill in the art to understand the present invention and thus design various embodiments with various modifications suitable for specific purposes.

[0030] Embodiment 1

[0031] Refer to Figure 1 , in this embodiment, a switch cabinet safety protection device is proposed for intelligent control of the temperature and humidity in the switch cabinet. The switch cabinet safety protection device may include:

[0032] A temperature sensing module, which is used to sense the temperature inside and outside the switchgear. The temperature sensing module is an electronic device for measuring and monitoring temperature, which can convert the change of temperature in the environment into a readable value and output it to the user. The temperature sensing module can convert the temperature signal into a corresponding electrical signal through internal sensor components such as thermistors (NTC), thermocouples, and infrared sensors. Among them, the thermistor is a resistance element whose resistance value changes according to the change of the thermal expansion coefficient of the material; the thermocouple is a device for temperature measurement using the thermoelectric effect of two different metals; the infrared sensor can sense the infrared radiation energy emitted by an object, and thus calculate the surface temperature of the object. The specific structure of the temperature sensing module is the prior art and will not be elaborated here. Two temperature sensing modules can be provided. One is set outside the switchgear to sense the temperature outside the switchgear. The sensed temperature is the temperature of the external environment of the switchgear. When the temperature inside the switchgear is too high and circulating air is required, it can drive the airflow in the external environment of the switchgear to cool the air inside the switchgear and the electronic components inside the switchgear. The other temperature sensing module can be installed inside the switchgear to sense the temperature inside the switchgear. In actual operation, when the electrical components inside the switchgear are working, a large amount of heat will be generated, and the generated heat needs to be discharged from the switchgear in time. Otherwise, the too high temperature inside the switchgear will cause the electrical components to overheat, which not only easily causes damage to the electrical components, but also may cause a fire and cause significant economic losses in severe cases. Of course, only a temperature sensing module can be installed inside the switchgear to obtain the temperature inside the switchgear. The temperature outside the switchgear can be obtained according to the weather forecast or obtained after being corrected by the weather forecast temperature, which will not be elaborated here.

[0033] Humidity sensing module, which is used to sense the humidity inside and outside the switchgear. The humidity sensing module is an electronic device used to detect the environmental humidity and convert it into a digital signal for output. The humidity sensing module mainly measures the humidity in the environment through various internal humidity sensors. The humidity obtained from the detection here is the absolute humidity, and the data of the absolute humidity is relatively objective and will not change due to air flow in different temperature environments. The humidity sensing module can also be set to two. One is set outside the switchgear to sense the humidity outside the switchgear, and the humidity it senses is the humidity of the environment outside the switchgear. When the temperature inside the switchgear is too high and circulating air is required, it can drive the air in the environment outside the switchgear to form an air flow to cool the electronic components inside the switchgear. At this time, the humidity in the environment will be introduced into the switchgear. The other humidity sensing module can be installed inside the switchgear to sense the humidity inside the switchgear. In actual operation, air humidity is an important parameter of the switchgear operating environment, and it will have a certain impact on the components inside the switchgear. The following are several impacts of air humidity on the components inside the switchgear: Impact on contact performance: The main function of key components such as circuit breakers and disconnectors in the switchgear is to transmit current through contact. When the air is humid, the insulating medium between the contacts may absorb moisture, resulting in a decline in electrical performance. Impact on metal materials: Changes in air humidity will cause changes in the electrochemical reactions of metal materials, which may cause corrosion of the metal materials. Especially for those key components exposed to a humid environment or operating in a humid environment, such as springs and contactors. Generally, when air enters the switchgear, its temperature will increase and its relative humidity will also increase. However, some electrical components inside the switchgear have very strict humidity tolerance requirements, and some are even lower than 50%. Therefore, it is necessary to control the humidity.

[0034] An air flow driving module is used to drive air into the switchgear cabinet, form an air flow inside the switchgear cabinet, and finally discharge the air from the switchgear cabinet. In the design of the switchgear cabinet, air inlets 6 and air outlets are generally provided on opposite sides of the switchgear cabinet. The air flow driving module can be a fan, an air pump, etc., and can be installed at the air inlet 6 or the air outlet. When the air flow driving module is started, it will drive air into the switchgear cabinet. The air forms an air flow and flows through the surfaces of various working electrical components, carrying away the heat generated by the electrical components, and finally discharging from the air outlet. Cooling by driving air to form an air flow is a common method, but it requires a certain temperature difference between the inside and outside of the switchgear cabinet, and the ambient temperature needs to meet the cooling requirements. If the temperature difference between the inside and outside of the switchgear cabinet is small, the effect of this simple cooling method is relatively poor, and the cooling purpose is often not achieved. Opening and closing leaves 3 can be provided at the positions of the air inlets 6 and air outlets of the switchgear cabinet. The opening and closing leaves 3 on the air inlet 6 can limit the entry of air only when driven by the air flow driving module. When there is an air flow, the air flow will drive the blades on the opening and closing leaves 3 to rotate, and there will be gaps for the air flow to pass through between the rotating blades, facilitating the entry of air. When the air flow driving module stops driving, the air flow disappears. Under the action of gravity, the blades of the opening and closing leaves 3 contact each other, and the gaps for the air flow to pass through disappear, separating the switchgear cabinet from the external environment and forming a sealed space, thus preventing external humidity from entering the switchgear cabinet.

[0035] A refrigeration module is used to refrigerate the air inside the switchgear cabinet. As mentioned above, when the temperature difference between the inside and outside of the switchgear cabinet is small, the effect of this simple cooling method is relatively poor, and the cooling purpose is often not achieved. At this time, the refrigeration module is needed for assistance. The refrigeration module is generally a condenser 2, and its specific structure is prior art and will not be elaborated here. The refrigeration module is generally arranged at the air inlet 6 and can refrigerate the air entering the switchgear cabinet, reducing the temperature of the air, thus facilitating better cooling of the electrical components inside the switchgear cabinet. It should be noted that a condensate water tank 4 needs to be provided below the refrigeration module. The condensate water tank 4 is fixedly connected to the inner side wall of the switchgear cabinet. The condensate water tank 4 is used to receive the water droplets condensed by the refrigeration module. A drain pipe 5 is fixedly connected to the bottom of the condensate water tank 4. The drain pipe 5 can extend out of the switchgear cabinet. The condensed water droplets enter the condensate water tank 4 and then are discharged from the switchgear cabinet through the drain pipe 5.

[0036] A control module is electrically connected to the temperature sensing module, the humidity sensing module, the air flow driving module, and the refrigeration module, and is used to receive the temperature and humidity values sensed by the temperature sensing module and the humidity sensing module, and is used to control the air flow driving module to drive the air flow and the refrigeration module to refrigerate. Refer to Figure 2 , and the specific control method can include: obtaining the internal temperature T 1 of the switchgear cabinet and the external temperature T 2 , the internal humidity AH 1and the external humidity AH 2 , determine whether the internal temperature T 1 is greater than a preset operating temperature T 1 标 . If not, cooling is not required. If so, determine whether the external temperature T 2 is less than a preset cooling temperature T 2 标 . Here, the preset operating temperature T 1 标 can be the maximum temperature for the normal use of the electrical components inside the switchgear. The specific obtaining method can include: obtaining the upper limit temperature of each electrical component inside the switchgear, and then taking the minimum upper limit temperature as the operating temperature T 1 标 . This method of obtaining the operating temperature T 1 标 is relatively simple, and can ensure that each electrical component can work within the normal temperature range, ensuring its use safety. However, this requires frequent cooling. If the cooling threshold is too low, a large amount of energy is required for maintenance, and the maintenance cost is relatively high. Of course, we can also calculate according to the tolerance of each electrical component. The specific calculation method includes: obtaining the information data and the upper limit temperature of use of various electrical components. Here, the upper limit temperature of use does not mean that the electrical component will be damaged when the temperature exceeds this temperature, but when working at this temperature, it will cause damage to the electrical component, and its loss is greater than the normal range. Its specific temperature varies according to the type, material, process, etc. of the electrical component, and will not be elaborated here. And sort them in ascending order according to the upper limit temperature of use, then calculate the optimized temperature T' of the electrical tolerance inside the switchgear, and take the optimized temperature T' of the electrical tolerance as the operating temperature T 1 标 . Refer to Figure 3 , the calculation method of the optimized temperature of the electrical tolerance can include: calculating the tolerance factor t of the electrical component, and the tolerance factor , where i and j are the sorting numbers of the electrical components, and t i is the tolerance coefficient of the electrical component numbered i, and I is the total number of types of electrical components. j≥i; i, j = 1, 2,..., I; First, let j = 1 and calculate the tolerance factor , then determine whether the tolerance factor is greater than a preset standard factor t 标 . If so, determine that the upper limit temperature of use of the electrical component corresponding to j is the optimized temperature T' of the electrical tolerance. If not, calculate the tolerance factor for j + 1 , and repeat the above steps. The standard factor t 标It can be set according to the actual situation. Specifically, it can balance power loss, equipment protection, etc., and can be adjusted in real time according to the actual situation. The specific details will not be elaborated here. For example, there are three electrical components A1, A2, and A3 in a switch cabinet. The upper limit temperatures corresponding to the three are 50°C, 55°C, and 60°C respectively, and the tolerance coefficients of the corresponding electrical components are 0.2, 0.3, and 0.4 respectively. By comprehensively considering the power and the protection of the switch cabinet, we set the standard factor t 标 to be 0.4. Then the process of calculating the optimized temperature T’ of electrical tolerance is as follows: Let j = 1, and the tolerance factor = 0.2. At this time, 0.2 is less than 0.4, so we continue to let j = 2, and the tolerance factor = 0.2 + 0.3 = 0.5. At this time, 0.5 is greater than 0.4, so we obtain the optimized temperature T’ of electrical tolerance as the upper limit temperature of the electrical component corresponding to A2, and the optimized temperature T’ of electrical tolerance is 55°C. Of course, this is just a simple example for easy understanding and does not have universality. The optimized temperature T’ of electrical tolerance can also be obtained by other methods, such as the upper limit temperature of the most important electrical component, the upper limit temperature of the median, etc. The specific details will not be elaborated here. The tolerance coefficient t i can be obtained based on experience, and of course it can also be obtained through calculation. The specific obtaining method can include the tolerance coefficient , where n is the tolerance factor number, f n is the tolerance factor value of the tolerance factor numbered n, N is the total number of tolerance factors, n = 1, 2,..., N; the tolerance factor is the value corresponding to the corresponding tolerance factor. The tolerance factors can include quantity, importance degree of electrical components, and damage degree of electrical components, which can be included in the information data of electrical components. The tolerance factor of quantity can be the quotient of the actual quantity and the standard quantity. The tolerance factor of the importance degree of electrical components can be set artificially and assigned according to the level. The tolerance factor of the damage degree of electrical components can be the damage level at the current upper limit temperature, which can be set artificially. Of course, we can also set it to a fixed value, but the calculation error is relatively large. Since it is not the protection theme of this application, the setting method will not be elaborated here. The cooling threshold set by this method is more reasonable, can intelligently analyze the performance of each electrical component, set a suitable cooling threshold, achieve component protection and reduce energy consumption, and achieve an optimized balance. For example, for an electrical component, the number of this electrical component in the switch cabinet is 8, the standard number is 10, its importance degree level is 3, the tolerance factor value corresponding to the importance degree level 3 is 0.6, and the tolerance factor of the damage degree of the electrical component at 55°C is 0.83. Then we can calculate and obtain the tolerance coefficient as 0.8×0.6×0.83 = 0.4. Of course, this is just a simple example for easy understanding and is not necessarily universal. The cooling temperature T2 标 The specific value can be obtained according to the working temperature T 1 标 and the cooling temperature difference. Specifically, it can be the cooling temperature T 2 标 =T 1 标 -ΔT, where ΔT is the standard temperature reduction difference and can be set according to specific circumstances, generally 10 - 30°C, and specific details are not elaborated here. When the external temperature T 2 is greater than the preset cooling temperature T 2 标 , the refrigeration module is turned on to cool the inside of the switch cabinet. When the external temperature T 2 is less than or equal to the preset cooling temperature T 2 标 , then it is judged whether the RH 1 标 at the working temperature T 2 is greater than a preset RH 2 标 . If not, the air flow driving module is normally controlled to drive air for cooling. If so, the air flow driving module and the refrigeration module are started. The air flow driving module drives air to enter, and the refrigeration module cools the entering air to the cooling temperature T0. In this way, it is possible to avoid bringing moisture in the air into the switch cabinet, avoid damage to electrical components when the humidity is too high, greatly protect electrical components, slow down corrosion in a humid environment, extend the service life of electrical components, and at the same time increase the use safety of the switch cabinet. In the present invention, it is defaulted that the air humidity will not be too small, and the situation of too small air humidity is very rare, so it is not considered in this application. The RH 1 标 at the working temperature T , where AH S is the saturated water vapor density at the working temperature T 1 标 , which is specifically the prior art and will not be elaborated here. The preset RH 2 标 can be determined according to specific actual situations. Generally, it is the lowest humidity upper limit of the electrical components in the switch cabinet, with a value of 50% - 90%, and specific details are not elaborated here. The cooling temperature T0 can be set manually according to experience, and of course, it can also be obtained through calculation. The specific obtaining method can include: calculating the working upper limit absolute humidity AH 2 ’, the working upper limit absolute humidity , and we preset the RH 1 标 at the working temperature T 2 标It works based on humidity, can meet the working requirements of electrical components at the critical temperature and humidity, and can protect electrical components to the greatest extent. Calculate the saturated water vapor density AHS' after cooling through the working upper limit absolute humidity, and then look up the pre-prepared saturated water vapor density-temperature information table according to the saturated water vapor density AHS' to obtain the cooling temperature T0. The saturated water vapor density-temperature information table is a prior art and will not be elaborated here. Specifically, it can be calculating the saturated water vapor density after cooling , where ΔAH is the deviation water vapor density. Theoretically, if the temperature of the incoming air is uniform and can be cooled to the cooling temperature, its value is zero. In the actual operation process, its value is generally 0.2 - 5 g / m 3 , of course, this value is not universal and specifically needs to be determined according to equipment parameters, the volume of the switch cabinet, temperature difference, air flow drive module, etc. Of course, the cooling temperature T0 can also have other setting methods and will not be elaborated here. By using this method to cool and dehumidify the switch cabinet, it can prevent the electrical components in the switch cabinet from working in an overheated and overhumid environment. While ensuring the normal operation of the electrical appliances, it can save energy to the greatest extent and reduce energy consumption.

[0037] Embodiment 2

[0038] Reference Figure 4 , the present invention also proposes a switch cabinet, which includes a cabinet body 1 and the above-mentioned switch cabinet safety protection device. An air inlet 6 and an air outlet are provided on the cabinet body 1, and the air flow drive module is installed at the air inlet 6 or the air outlet. The refrigeration module is installed on the inner wall of the cabinet body 1 at the air inlet 6 position. The control module can be set on the cabinet body 1 or can be remotely controlled, specifically set according to actual needs. A condensation water tank 4 is installed on the inner side wall of the cabinet body 1. The condensation water tank 4 is located below the refrigeration module. The condensation water tank 4 is used to receive the water droplets condensed by the refrigeration of the refrigeration module. A drain pipe 5 is fixedly connected to the bottom of the condensation water tank 4. The drain pipe 5 can extend out of the cabinet body 1. The condensed water droplets enter the condensation water tank 4 and then are discharged from the cabinet body 1 through the drain pipe 5. Obtain the internal temperature T 1 of the switch cabinet and the external temperature T 2 , the internal humidity AH 1 of the switch cabinet and the external humidity AH 2 , judge whether the internal temperature T 1 is greater than a preset working temperature T 1 标 . If not, cooling is not required; if so, judge whether the external temperature T 2 is less than a preset cooling temperature T 2 标 . If not, turn on the refrigeration module to cool the inside of the switch cabinet. If so, judge the working temperature T 1标 RH below 2 is greater than a preset RH 2 标 , if not, the air flow driving module is normally controlled to drive air for cooling; if so, the air flow driving module and the refrigeration module are started. The air flow driving module drives air to enter, and the refrigeration module cools the entering air to the cooling temperature T0. In this way, the moisture in the air can be prevented from being brought into the switch cabinet, avoiding damage to electrical components when the humidity is too high, greatly protecting the electrical components, slowing down the corrosion in a humid environment, prolonging the service life of the electrical components, and increasing the use safety of the switch cabinet at the same time.

[0039] At the air inlet 6 and the air outlet position of the cabinet body 1, there may be provided hinge leaves 3. The hinge leaves 3 on the air inlet 6 can limit the air to enter only when driven by the air flow driving module. When there is an air flow, the air flow will drive the blades on the hinge leaves 3 to rotate, and there will be gaps for the air flow to pass through between the rotating blades, so as to facilitate the entry of air. When the air flow driving module stops driving, the air flow disappears, and under the action of gravity, the blades of the hinge leaves 3 contact each other, and the gaps for the air flow to pass through disappear, separating the switch cabinet from the external environment to form a sealed space, thus preventing the external humidity from entering the switch cabinet.

[0040] Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art and related fields based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. The structures, devices, and operation methods not specifically described and explained in the present invention, unless otherwise specified and limited, are implemented according to the conventional means in the art.

Claims

1. A safety protection device for a switch cabinet, characterized in that, The described switchgear safety protection device includes: a temperature sensing module for sensing the temperature inside and outside the switchgear; a humidity sensing module for sensing the humidity inside and outside the switchgear; an air flow driving module for driving air into the switchgear; a refrigeration module for refrigerating the air inside the switchgear; The control module is electrically connected to the temperature sensing module, the humidity sensing module, the air flow driving module, and the refrigeration module, and is used to obtain the internal temperature T of the switch cabinet 1 , the external temperature T 2 and the external humidity AH of the switch cabinet 2 ; judge whether the internal temperature T 1 is greater than a preset working temperature T 1 标 , if not, cooling is not required; if so, judge whether the external temperature T 2 is less than a preset cooling temperature T 2 标 , if not, turn on the refrigeration module to cool the inside of the switch cabinet; if so, judge the relative humidity RH outside the switch cabinet at the working temperature T 1 标 whether it is greater than a preset standard relative humidity RH 2 2 标 , if not, control the air flow driving module to drive the air for cooling, if so, start the air flow driving module and the refrigeration module, the air flow driving module drives the air to enter, and the refrigeration module cools the entering air to the cooling temperature T0;​ The preset operating temperature T 1 标 The calculation method includes: obtaining the information data and upper limit temperature of various electrical components, sorting them from low to high according to the upper limit temperature, then calculating the optimized temperature T' tolerated by the electrical appliances in the switchgear, and using the optimized temperature T' tolerated by the electrical appliances as the operating temperature T 1 标 ; The calculation method for the optimized temperature tolerated by the electrical appliance includes: calculating the tolerance factor t of the electrical appliance components, and the tolerance factor , where i and j are the sorting numbers of the electrical appliance components, and t i is the tolerance coefficient of the electrical appliance component numbered i, and I is the total number of types of electrical appliance components; j ≥ i; i, j = 1, 2,..., I; First, let j = 1 and calculate the tolerance factor, and then determine whether the calculated tolerance factor is greater than a preset standard factor t 标 . If so, it is determined that the upper limit temperature of the electrical appliance component corresponding to j is the optimized temperature T' tolerated by the electrical appliance. If not, calculate the tolerance factor for j + 1 and repeat the determination; Tolerance coefficient , where n is the tolerance factor number, and f n is the tolerance factor value of the tolerance factor numbered n, N is the total number of tolerance factors, and n = 1, 2,..., N; the tolerance factors include quantity, importance degree of electrical components, and damage degree of electrical components.

2. The safety protection device for a switch cabinet according to claim 1, characterized in that, Cooling temperature T 2 标 = T 1 标 - ΔT, where ΔT is the standard temperature drop difference.

3. A safety protection device for a switch cabinet according to claim 1, characterized in that, The working temperature T 1 标 at which , where AH S is the saturated water vapor density 1 标 at the working temperature T 4. The safety protection device for a switch cabinet according to claim 3, wherein, The method for obtaining the cooling temperature T0 includes: calculating the absolute humidity AH at the working upper limit 2 ’, obtaining the saturated water vapor density AHS’ after cooling through calculation based on the absolute humidity at the working upper limit, and then looking up the pre-prepared saturated water vapor density-temperature information table according to the saturated water vapor density AHS’ to obtain the cooling temperature T0.

5. A switch cabinet, characterized in that, The switchgear includes: a cabinet body, and the switchgear safety protection device according to any one of claims 1-4.

6. A switch cabinet according to claim 5, characterized in that, A condensation water tank is installed on the inner side wall of the cabinet body. The condensation water tank is located below the refrigeration module. The condensation water tank is used to receive the water droplets condensed by the refrigeration of the refrigeration module. A drain pipe is fixedly connected to the bottom of the condensation water tank. The drain pipe extends out of the cabinet body. The condensed water droplets enter the condensation water tank and then are discharged from the cabinet body through the drain pipe.

7. A switchgear according to claim 6, characterized in that, An air inlet and an air outlet are provided on the cabinet body, and opening and closing leaves are arranged at the positions of the air inlet and the air outlet of the cabinet body.

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