Semiconductor condensation dehumidification device of high-voltage switch cabinet and control method

Abstract

The invention belongs to the field of condensation and dehumidification of electrical equipment, and particularly relates to a semiconductor condensation and dehumidification device of a high-voltage switch cabinet and a control method. The semiconductor condensation and dehumidification device is installed in the high-voltage switch cabinet and used for condensation and dehumidification of the interior of the high-voltage switch cabinet; comprising a shell, a fan, a ventilation hole, a semiconductor chilling plate, a drainage assembly and an environmental parameter sensor. The fan and the ventilation hole are arranged on the side surface or the top surface of the shell and are arranged on different wall surfaces; the semiconductor chilling plate is arranged in the shell, and the hot end faces the fan; the drainage assembly is arranged below the semiconductor chilling plate; and the environmental parameter sensor is arranged in the high-voltage switch cabinet. Compared with the prior art, the problem that in the prior art, a semiconductor condensation dehumidification device of a field high-voltage switch cabinet is low in dehumidification efficiency is solved; according to the scheme, the layout structure of the device is optimally designed, and the energy transfer and air convection processes of the cold end and the hot end of the semiconductor chilling plate are improved, so that the reliability of the device in practical application is improved.

Description

Technical Field

[0001] The present invention belongs to the field of condensation dehumidification of electrical equipment, and particularly relates to a semiconductor condensation dehumidification device and a control method for a high-voltage switch cabinet. Background Art

[0002] With the growth of power demand and the expansion of the power grid, the application prospect of high-voltage switch cabinets is very broad. However, during the operation of high-voltage switch cabinets, they are often affected by high-humidity environments. Most of the existing high-voltage switch cabinets adopt sealed packaging, which has good safety and stability in dry environments. However, in humid environments, due to the limited sealing degree of the cabinet body, water molecules in the external air will inevitably enter the interior of the high-voltage switch cabinet. If the moisture in the cabinet cannot be discharged in time, once the surface temperature of the components in the high-voltage switch cabinet in contact with the air is lower than the dew point temperature of the air, condensation will occur on the surface of the components, causing corrosion of metal contacts and a decline in the insulation performance of cables. This will not only reduce the service life of electrical equipment, but in severe cases, it will also affect the normal operation of the power system, greatly reducing the safety and reliability of power supply, resulting in economic losses and negative impacts. Therefore, researching a moisture suppression method suitable for high-voltage switch cabinets and improving the safety and reliability of the operation of high-voltage switch cabinets are major problems that need to be solved urgently in the power industry.

[0003] The thermoelectric condensation technology with semiconductor materials as the main body is one of the commonly used methods in the field of condensation dehumidification of conventional electrical equipment. The basic principle of this method is to cool the ambient temperature below the dew point temperature through refrigeration, condense water vapor into liquid water at the refrigeration end, and then complete the refrigeration and dehumidification process by adsorptive drying or collecting condensed water through a drain pipe. After retrieving the existing semiconductor condensation dehumidification technology, it is found that Chinese Patent Document No. CN207688453U, publication date August 3, 2018, discloses an intelligent semiconductor condensation dehumidification device; and Chinese Patent Document No. CN206516904U, a condensation dehumidification device for a semiconductor element of a switch cabinet, publication date September 22, 2017. Both use a semiconductor refrigeration sheet to dehumidify the air. When a direct current flows through the semiconductor refrigeration sheet composed of multiple parallel semiconductor thermocouples, a temperature difference will appear at the interface position. Among them, the cold end absorbs heat from the outside, and the temperature of the interface decreases, thus achieving the refrigeration effect. The above patents prove the feasibility of the application of the semiconductor condensation method in the dehumidification of electrical equipment from theoretical derivation and method application.

[0004] At present, in the application of the above method in on-site high-voltage switchgear, the semiconductor condensation dehumidification device is generally directly fixed on the wall of the high-voltage switchgear. Due to the relatively complex temperature and humidity distribution and actual structure of the operating environment of on-site high-voltage switchgear, the semiconductor condensation dehumidification device generally has practical application defects such as low dehumidification efficiency and cannot be well put into operation in the on-site high-voltage switchgear. Therefore, in order to improve the practicality of the semiconductor condensation dehumidification device, it is necessary to optimize its layout structure and control strategy. Summary of the Invention

[0005] The purpose of the present invention is to provide a semiconductor condensation dehumidification device and control method for high-voltage switchgear to solve at least one of the above problems, so as to solve the problem of low dehumidification efficiency of the semiconductor condensation dehumidification device for on-site high-voltage switchgear in the prior art; this solution optimizes the layout structure of the device, improves the energy transfer and air convection processes at the cold and hot ends of the semiconductor refrigeration sheet, and improves its reliability in practical applications.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] The first aspect of the present invention discloses a semiconductor condensation dehumidification device for high-voltage switchgear, which is installed inside the high-voltage switchgear and used for condensation dehumidification of the inside of the high-voltage switchgear;

[0008] The semiconductor condensation dehumidification device includes a housing, a fan, ventilation holes, a semiconductor refrigeration sheet, a drainage assembly and an environmental parameter sensor;

[0009] The fan and the ventilation holes are respectively arranged on the side or top surface of the housing, and the fan and the ventilation holes are arranged on different walls to form an air exchange flow channel;

[0010] The semiconductor refrigeration sheet is arranged inside the housing, and its hot end faces the fan;

[0011] The drainage assembly is arranged below the semiconductor refrigeration sheet;

[0012] The environmental parameter sensor is arranged inside the high-voltage switchgear.

[0013] Preferably, the drainage assembly includes a water collecting tank and a drain pipe; the water collecting tank is arranged on the bottom surface of the housing, and the drain pipe is connected from the water collecting tank to the outside of the high-voltage switchgear.

[0014] Preferably, the upper surface of the water collecting tank is a concave surface with a lowest point; one end of the drain pipe is connected to the lowest point of the water collecting tank.

[0015] Preferably, the fan is arranged on the top surface of the housing, the ventilation holes are arranged on the side surface of the housing, and the semiconductor refrigeration sheet is arranged horizontally.

[0016] Preferably, a plurality of the ventilation holes are provided and are arranged in an array on the side surface of the housing.

[0017] Preferably, the ventilation holes are provided on a plurality of wall surfaces of the housing.

[0018] Preferably, a heat sink is further attached to the cold end and / or the hot end of the semiconductor refrigeration chip.

[0019] Preferably, a plurality of the semiconductor refrigeration chips are provided.

[0020] Preferably, the environmental parameter sensor includes a temperature sensor and a humidity sensor.

[0021] A second aspect of the present invention discloses a control method for the semiconductor condensation dehumidification device of the high-voltage switchgear as described in any one of the above, and determines the operating state of the semiconductor condensation dehumidification device based on the temperature and humidity inside the high-voltage switchgear detected by the environmental parameter sensor.

[0022] Preferably, it is set that: the second temperature limit T 2 , the second humidity limit RH start , the first temperature limit T 1 and the first humidity limit RH stop , wherein, the second temperature limit T 2 ≥ the first temperature limit T 1 , the second humidity limit RH start ≥ the first humidity limit RH stop ;

[0023] When the detected ambient temperature ≥ the second temperature limit T 2 , and the detected ambient humidity ≥ the second humidity limit RH start , then start the semiconductor condensation dehumidification device in the refrigeration mode;

[0024] When the detected ambient humidity ≥ the second humidity limit RH start , and the detected ambient humidity ≤ the first temperature limit T 1 , then start the semiconductor condensation dehumidification device in the defrosting mode;

[0025] When the detected ambient humidity ≤ the first humidity limit RH stop , then the semiconductor condensation dehumidification device stops;

[0026] When the detected ambient humidity is between the first humidity limit RH stop and the second humidity limit RH start , or, when the detected ambient humidity ≥ the first humidity limit RH stop , and the detected ambient humidity is between the first temperature limit T 1Between the second temperature limit T 2 Then, the semiconductor condensation dehumidification device maintains the previous state unchanged.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention is a method for optimizing the semiconductor condensation layout and its device for overall dehumidification of on-site high-voltage switchgear. The usage scenario of the device is as follows: when the humidity of the air inside the high-voltage switchgear is too high, it is necessary to cool and condense the moisture in the air and collect and discharge the condensed water. As a condensation device, this device can achieve overall dehumidification inside the high-voltage switchgear, is applicable to on-site high-voltage switchgears of different types and sizes, and can also solve the problems of large temperature differences between the hot end and the cold end of the on-site semiconductor condensation dehumidification device and low condensation dehumidification efficiency caused by the inability to maintain the cold end temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic structural diagram of a semiconductor condensation dehumidification device;

[0030] Figure 2 It is a schematic flowchart of start-stop judgment in the control method;

[0031] Figure 3 It is a schematic partition diagram of mode switching in the control method;

[0032] Figure 4 It is a schematic diagram of air convection in a high-voltage switchgear provided with the semiconductor condensation dehumidification device;

[0033] In the figure: 1 - fan; 2 - ventilation hole; 3 - semiconductor refrigeration sheet; 4 - water collecting tank; 5 - drain pipe. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The present invention will be described in detail below with reference to the drawings and specific embodiments.

[0035] Embodiment

[0036] A semiconductor condensation dehumidification device for a high-voltage switchgear, as Figure 1 shown, the semiconductor condensation dehumidification device is installed inside the high-voltage switchgear and is used for condensation dehumidification inside the high-voltage switchgear;

[0037] The semiconductor condensation dehumidification device includes a housing, a fan 1, a ventilation hole 2, a semiconductor refrigeration sheet 3, a drainage assembly, and an environmental parameter sensor;

[0038] The fan 1 and the ventilation hole 2 are respectively arranged on the side surface or the top surface of the housing, and the fan 1 and the ventilation hole 2 are arranged on different walls to form an air exchange flow channel;

[0039] The thermoelectric cooler 3 is disposed inside the housing, and its hot end faces the fan 1;

[0040] The drainage assembly is disposed below the thermoelectric cooler 3;

[0041] The environmental parameter sensor is disposed inside the high-voltage switchgear.

[0042] More specifically, in this embodiment:

[0043] As Figure 1 shown, the semiconductor condensation dehumidification device is installed inside the high-voltage switchgear and is composed of a housing, a fan 1, ventilation holes 2, a thermoelectric cooler 3, a water collecting tank 4, and a drain pipe 5. In addition, an environmental parameter sensor including a temperature sensor and a humidity sensor is also disposed inside the high-voltage switchgear for real-time determination of the environmental state; heat sinks are also attached to the hot end and / or cold end of the thermoelectric cooler 3 to assist in heat transfer.

[0044] The fan 1 is installed at the center of the top surface of the housing; the ventilation holes 2 are disposed on the side wall of the housing and are spaced apart along the height direction; a pair of thermoelectric coolers 3 are disposed, one above the other, in the internal cavity of the housing, and the hot end faces the fan 1. Among them, the upper thermoelectric cooler 3 is attached to a heat sink at the hot end, and the lower thermoelectric cooler 3 is attached to a heat sink at the cold end; the water collecting tank 4 is located at the bottom surface of the housing and below the thermoelectric cooler 3, and its upper surface is a concave surface with a lowest point; one end of the drain pipe 5 is connected to the lowest point of the water collecting tank 4, and the other end extends out of the high-voltage switchgear. Thus, the inside of the housing can be divided into a condensation area (from the lower thermoelectric cooler 3 to the water collecting tank 4), a cold end area (the lower thermoelectric cooler 3), a thermocouple area (between the two thermoelectric coolers 3), and a hot end area (from the upper thermoelectric cooler 3 to the fan 1); in addition, ventilation holes 2 can be provided on the sides of the two thermoelectric coolers 3, and ventilation holes 2 can be provided on the side edges of multiple sides as needed.

[0045] The entire air convection mode inside the high-voltage switchgear including the semiconductor condensation dehumidification device is as Figure 4As shown in the figure. The semiconductor condensation dehumidification device can be divided into four regions: In the hot end region, the hot end is cooled by natural heat dissipation through air convection and forced air cooling. Utilizing the upward trend of hot air, the fan 1 closely attached to the heat sink at the hot end of the semiconductor refrigeration chip 3 is installed at the top of the device, discharging the heat of the hot end from the device faster and reducing the interference of hot air on the cold end. In the thermocouple region, external air enters the semiconductor condensation dehumidification device through the ventilation holes 2 on both sides. Two kinds of air with a temperature gradient are formed through the action of the semiconductor refrigeration chip 3. Among them, the cold air sinks to the cold end region and the condensation region, and the hot air rises to the hot end region. In the cold end region, the cooling capacity of the semiconductor refrigeration chip 3 is transferred to the condensation region through the heat sink attached to its cold end. In the condensation region, the cold air with a low temperature converges here, and condensation occurs on the surface of the heat sink where the temperature is lower than the dew point temperature. The generated condensed water drips into the water collection tank 4 under the action of gravity and converges in the middle of the water collection tank 4 through the arc height difference, and is discharged from the high-voltage switchgear through the drain pipe 5 at the bottom, completing the suppression of the water molecule content in the cabinet. Among them, by controlling the vertical position of the ventilation opening 2, the humid air in the high-voltage switchgear outside the semiconductor condensation dehumidification device can pass directly through the semiconductor refrigeration chip 3 as much as possible, accelerating the processing efficiency of the semiconductor refrigeration chip 3 on it and reducing its impact on the cold end region and the condensation region.

[0046] Based on this: First, in the hot end region, the hot end of the semiconductor refrigeration chip 3 is cooled by natural heat dissipation through air convection and forced air cooling, and the hot air is discharged from the housing by the installed fan 1 to reduce the interference of hot air on the cold end. Second, in the thermocouple region, external air enters the semiconductor condensation dehumidification device through the ventilation holes 2 on both sides. Two kinds of air with a temperature gradient are formed under the action of the semiconductor refrigeration chip 3. Among them, the cold air sinks to the cold end region and the condensation region, and the hot air rises to the hot end region. Third, in the cold end region, the semiconductor refrigeration chip 3 transfers the low temperature from the cold end to the condensation region. Finally, in the condensation region, the cold air converges and condensation occurs on the surface of the semiconductor refrigeration chip 3. The generated condensed water drips into the water collection tank 4 under the action of gravity and is converged in the middle through the arc height difference of the tank to complete the collection, and is discharged from the high-voltage switchgear through the drain pipe 5 to complete the dehumidification process.

[0047] In addition to the above arrangement, in other embodiments, the top surface of the device can also be closely attached to the cabinet wall of the high-voltage switchgear, and the fan 1 is installed on both wall surfaces. Thus, in addition to the fan 1 discharging hot air, the top surface can also directly transfer the heat to the cabinet wall and further exchange heat with the environment. Since solids usually have good thermal conductivity, efficient local heat dissipation can be achieved within a short distance.

[0048] A control method for a semiconductor condensation dehumidification device of a high-voltage switchgear as above. Based on the above structure, a PWM controller is also provided, which is electrically connected to the semiconductor refrigeration sheet 3, the fan 1, and the environmental parameter sensor. As Figure 2 FIG. Figure 2 shows a schematic flow chart of the control strategy of the device. The working states of the device include three set states: start, stop, and forced start, and the operating modes include two types: refrigeration and defrosting. The environmental parameter sensor measures the ambient temperature and humidity in real time. When it detects that the ambient humidity is higher than the start set value, it judges the ambient temperature to automatically select or switch between the refrigeration and defrosting modes. If a forced start instruction is directly received (a control button can be set on the housing or outside the high-voltage switchgear), it will directly start working (for example, buttons for refrigeration and defrosting can be set respectively, and the corresponding mode is started according to the received instruction). When the operating mode is refrigeration, the semiconductor refrigeration sheet 3 outputs normally, and the cooling fan 1 works normally. When the operating mode is defrosting, the output power of the semiconductor refrigeration sheet 3 decreases but does not stop, and the cooling fan 1 can stop working or run at a low speed. The control is based on PWM, and the duty cycle is adjusted according to the set state and operating mode to control the output power of the semiconductor refrigeration sheet 3. In other embodiments, a PLC controller can also be used as the overall control, and PWM is used to control the output of the fan 1 and the semiconductor refrigeration sheet 3. The controllers, control circuits, etc. mentioned here can all adopt existing technologies and are commercially available products.

[0049] Figure 3 Further shows the specific basis and conditions for mode switching. By adopting different layout structure schemes and different control strategies, it can adapt to different environmental conditions and actual needs. Set: the second temperature limit T 2 , the second humidity limit RH start , the first temperature limit T 1 and the first humidity limit RH stop , where the second temperature limit T 2 ≥ the first temperature limit T 1 , the second humidity limit RH start ≥ the first humidity limit RH stop ; ① When the detected ambient temperature ≥ the second temperature limit T 2 , and the detected ambient humidity ≥ the second humidity limit RH start , then start the semiconductor condensation dehumidification device in the refrigeration mode; ② When the detected ambient humidity ≥ the second humidity limit RH start , and the detected ambient humidity ≤ the first temperature limit T 1 , then start the semiconductor condensation dehumidification device in the defrosting mode; ③ When the detected ambient humidity ≤ the first humidity limit RH stop , then the semiconductor condensation dehumidification device stops; ④ When the detected ambient humidity is between the first humidity limit RH stop and the second humidity limit RH startbetween, or when the detected ambient humidity ≥ the first humidity limit RH stop and the detected ambient humidity is between the first temperature limit T 1 and the second temperature limit T 2 then the semiconductor condensation dehumidification device maintains the previous state unchanged. Under this control logic, it has higher dehumidification efficiency and equipment stability.

[0050] Compared with the traditional dehumidification method for high-voltage switchgear, the present invention adopts a semiconductor condensation dehumidification system, and through optimizing the layout structure, it has higher heat dissipation efficiency, thereby improving the dehumidification efficiency, reducing the moisture level of the equipment, and improving the reliability and stability of the equipment.

[0051] The above description of the embodiments is to enable those of ordinary skill in the art to understand and use the invention. Obviously, those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and the improvements and modifications made by those skilled in the art without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. A semiconductor condensation dehumidification device for a high-voltage switch cabinet, characterized in that: The semiconductor condensation and dehumidification device is installed inside the high-voltage switch cabinet and is used to condense and dehumidify the interior of the high-voltage switch cabinet; The semiconductor condensation dehumidification device comprises a housing, a fan (1), a ventilation hole (2), a semiconductor refrigeration sheet (3), a drainage component and an environmental parameter sensor; The fan (1) and the ventilation hole (2) are respectively arranged on the side surface or the top surface of the shell, and the fan (1) and the ventilation hole (2) are arranged on different wall surfaces to form a ventilation air passage; The semiconductor cooling sheet (3) is arranged inside the housing, with its hot end facing the fan (1); The drainage component is arranged below the semiconductor cooling sheet (3); The environmental parameter sensor is arranged inside the high-voltage switch cabinet.

2. The semiconductor condensation dehumidification device of a high-voltage switch cabinet according to claim 1, characterized in that: The drainage assembly comprises a water collecting tank (4) and a drainage pipe (5); the water collecting tank (4) is arranged on the bottom surface of the shell, and the drainage pipe (5) is connected to the outside of the high-voltage switch cabinet through the water collecting tank (4).

3. The semiconductor condensation dehumidification device of a high-voltage switch cabinet according to claim 2, characterized in that: The upper surface of the water collecting tank (4) is concave and has a lowest point; one end of the drainage pipe (5) is connected to the lowest point of the water collecting tank (4).

4. The semiconductor condensation dehumidification device for a high-voltage switch cabinet according to claim 1, characterized in that: The fan (1) is arranged on the top surface of the shell, the ventilation hole (2) is arranged on the side of the shell, and the semiconductor cooling plate (3) is arranged horizontally.

5. The semiconductor condensation dehumidification device for a high-voltage switch cabinet according to claim 1, characterized in that: A plurality of ventilation holes (2) are provided and arranged in an array on the side of the shell.

6. The semiconductor condensation dehumidification device for a high-voltage switch cabinet according to claim 1, characterized in that: The cold end and / or the hot end of the semiconductor refrigeration sheet (3) is also fitted with a heat sink.

7. The semiconductor condensation dehumidification device for a high-voltage switch cabinet according to claim 1, characterized in that: The semiconductor cooling sheet (3) is provided with a plurality of pieces.

8. The semiconductor condensation dehumidification device for a high-voltage switch cabinet according to claim 1, characterized in that: The environmental parameter sensors include a temperature sensor and a humidity sensor.

9. A control method for a semiconductor condensation dehumidification device of a high-voltage switch cabinet according to any one of claims 1 to 8, characterized in that: Based on the temperature and humidity inside the high-voltage switch cabinet detected by the environmental parameter sensor, the operating state of the semiconductor condensation dehumidification device is determined.

10. The control method of a semiconductor condensation dehumidification device of a high-voltage switch cabinet according to claim 9, characterized in that: Settings: Second temperature limit T2, second humidity limit RH start , the first temperature limit T1 and the first humidity limit RH stop , where the second temperature limit T2 ≥ the first temperature limit T1, the second humidity limit RH start ≥First humidity limit RH stop ; When the detected ambient temperature ≥ the second temperature limit T2, and the detected ambient humidity ≥ the second humidity limit RH start , then start the semiconductor condensation dehumidification device in cooling mode; When the detected ambient humidity ≥ the second humidity limit RH start , and the detected ambient humidity is ≤ the first temperature limit T1, the semiconductor condensation dehumidification device is started in the defrost mode; When the detected ambient humidity is ≤ the first humidity limit RH stop , then the semiconductor condensation dehumidification device stops; When the detected ambient humidity is between the first humidity limit RH stop The second humidity limit RH start or, when the detected ambient humidity ≥ the first humidity limit RH stop , and the detected ambient humidity is between the first temperature limit T1 and the second temperature limit T2, the semiconductor condensation dehumidification device maintains the previous state unchanged.

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