Cooling scheme of low-voltage cabinet

Abstract

The invention belongs to the field of switch cabinets, and provides a cooling scheme of a low-voltage cabinet, the low-voltage cabinet comprises a cabinet body, a busbar, an electromagnetic detection device, an electromagnetic suppression device and a heat dissipation module, the cabinet body further comprises a bus bin, the busbar is arranged in the bus bin, the electromagnetic detection device is arranged on the side wall of the cabinet body of the bus bin, and the electromagnetic suppression device is arranged on the surface of the inner wall of the cabinet body. The heat dissipation module is arranged at the top of the bus bin; the electromagnetic detection device detects the size and direction of a magnetic field in the cabinet body; the electromagnetic suppression device generates reverse magnetic flux according to a magnetic field signal detected by the electromagnetic detection device in real time so as to suppress an interference magnetic field from forming eddy current in the cabinet body; the heat dissipation module comprises a thin film cooling module, and when a signal detected by the electromagnetic detection device exceeds a threshold value, the thin film cooling module is started for emergency cooling. While the heat dissipation effect is improved, the eddy current loss of the cabinet body caused by the magnetic field in the cabinet is inhibited.

Description

Technical Field

[0001] This application relates to the technical field of switch cabinets, and particularly to a cooling solution for low-voltage cabinets. Background Art

[0002] As an important part of the circuit, low-voltage power distribution cabinets play a very important role. However, the current or magnetic field in the low-voltage power distribution cabinet is too large. During the use of the switch cabinet, eddy currents will be generated, which will cause the cabinet body to heat up, affect the overall temperature of the electronic and electrical equipment, cause the temperature rise of the cabinet body to intensify and the local temperature to be too high, and have a great impact on the performance of the insulating parts and the service life of the equipment. It will cause the temperature in the cabinet to rise suddenly, resulting in equipment damage and insulation degradation. How to effectively reduce the air humidity in the low-voltage power distribution cabinet and quickly refrigerate to improve the power supply reliability is a problem before us. Summary of the Invention

[0003] In order to solve the temperature rise problem caused by magnetic field eddy currents in the prior art, a magnetic field sensor and a thin film cooling module are arranged in the switch cabinet. The temperature will be controlled directly through the magnetic field change signal, and a magnetic field shielding device is set to protect the cabinet body simultaneously in a two-pronged manner.

[0004] An embodiment of this application provides a cooling solution for a low-voltage cabinet, including a cabinet body, a bus bar, an electromagnetic detection device, an electromagnetic suppression device, and a heat dissipation module; The cabinet body further includes a bus bar bin, the bus bar is arranged in the bus bar bin, the electromagnetic detection device is arranged on the cabinet body side wall of the bus bar bin, the electromagnetic suppression device is arranged on the inner wall surface of the cabinet body, and the heat dissipation module is arranged on the top of the bus bar bin; The electromagnetic detection device detects the magnitude and direction of the magnetic field in the cabinet body; The electromagnetic suppression device generates a reverse magnetic flux according to the magnetic field signal detected by the electromagnetic detection device in real time, so as to suppress the formation of eddy currents by the interference magnetic field in the cabinet body; The heat dissipation module includes a thin film cooling module. When the signal detected by the electromagnetic detection device exceeds the threshold, the thin film cooling module is started for emergency cooling.

[0005] In some embodiments, there are at least 3 electromagnetic detection devices, which are respectively arranged on different inner side walls of the cabinet body, and their output ends are connected to the input unit of the main control unit.

[0006] In some embodiments, the electromagnetic suppression device is of a flat structure and includes a coil device, whose input end is connected to the main control unit. The main control unit calculates the magnitude of the current to be output according to the signal detected by the electromagnetic induction device, and thus outputs a reverse current to form a reverse magnetic flux.

[0007] In some embodiments, the film cooling module includes a cooling cavity, in which a phase change material is disposed. After being excited, the phase change material refrigerates, thereby forming cold air in the cooling cavity.

[0008] In some embodiments, the phase change material refrigerates through the magnetocaloric effect or an electrochemical reaction.

[0009] In some embodiments, a bladder is disposed in the cooling cavity, and the phase change material is coated in the bladder. There is a gap for air circulation between the bladder and the cooling cavity.

[0010] In some embodiments, the cabinet further includes a pressure relief cover plate, on which a fan is disposed. The fan includes a first fan that sucks air inward and a second fan that blows air outward. The first fan is located above the film cooling module.

[0011] In some embodiments, there are 2 second fans, which are respectively arranged on both sides of the first fan.

[0012] In some embodiments, air holes are provided on the bottom wall of the cooling cavity. The shape of the air hole channel is inclined, and the opening of the air hole is inclined toward the second fan.

[0013] In some embodiments, the film cooling module sinks into the cabinet interior. When the film cooling module is turned on, the cooling air flow is sprayed toward the bottom of the cabinet at a certain angle through the air holes and forms a cooling air flow with a curvature. After mixing with the hot air, the hot air flow is discharged through the second fan.

[0014] Compared with the prior art, the beneficial effects that the present application can achieve are as follows: 1. In the present application, a magnetic field sensor is used to detect the change of the magnetic field in the cabinet, and then the temperature rise information is obtained through the relationship between the magnetic field signal and the temperature rise. Compared with the traditional temperature sensor monitoring, the problem of reduced detection accuracy caused by the influence of the magnetic field on the temperature sensor and the operation of the cooling device in the cabinet is avoided.

[0015] 2. In the present application, a magnetic field sensor is used to detect the change of the magnetic field in the cabinet, directly aiming at the eddy current problem caused by the interfering magnetic field in the cabinet. Using this magnetic field change information, temperature control and magnetic field shielding control can be carried out simultaneously, reducing the arrangement and use of environmental monitoring sensors in the cabinet, simplifying the arrangement of internal components, reducing the complexity of control, and improving the space utilization rate.

[0016] 3. The film cooling module adopted in the present application can be started when the temperature in the cabinet rises suddenly and stopped when the temperature is stable, which can protect the equipment in the cabinet from high-temperature damage while reducing the daily energy consumption.

[0017] 4. The film cooling module adopted in this application can achieve rapid counter-flow cooling through the design of the flow channel for the cooling gas. Meanwhile, it increases the flow area of the cooling gas and the gas convection efficiency, greatly improving the cooling effect.

[0018] 5. The electromagnetic suppression device adopted in this application cancels out the interfering magnetic field inside the switch cabinet through an active control method, enhancing the shielding effect of the switch cabinet, reducing the eddy current loss of the cabinet body, and protecting the insulation performance of the cabinet body.

[0019] To make the above objects, features, and advantages of this application more obvious and understandable, the following specifically gives preferred embodiments and, in conjunction with the accompanying drawings, makes a detailed description as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the following briefly introduces the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other relevant drawings can be obtained based on these drawings.

[0021] Figure 1 Shows a schematic structural diagram of a temperature reduction solution for a low-voltage cabinet of this application; Figure 2 Shows a schematic structural diagram of the busbar chamber of a temperature reduction solution for a low-voltage cabinet of this application; Figure 3 Shows a schematic structural diagram of an emergency heat dissipation device of this application; Figure 4 Shows a schematic structural diagram of another emergency heat dissipation device of this application; Figure 5 Shows a schematic structural diagram of another emergency heat dissipation device of this application; Figure 6 Shows a top view of the layout of the heat dissipation module in the pressure relief chamber of this application.

[0022] In the figure: 1 - cabinet body, 2 - busbar, 3 - pressure relief chamber, 41 - air inlet, 42 - air outlet, 43 - air inlet channel, 44 - exhaust channel, 5 - electromagnetic detection device, 6 - busbar chamber, 7 - emergency heat dissipation device, 71 - first fan, 72 - film cooling module, 73 - cooling cavity, 74 - bladder, 75 - phase change material, 76 - air hole, 8 - second fan, 91 - cooling air flow, 92 - hot air flow, 10 - electromagnetic suppression device. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] In the description and claims of this application and the accompanying drawings, the terms "comprising", "including", "containing" or "characterized by" are synonymous, and are inclusive of endpoints or open-ended, and do not exclude additional unrecited elements or method steps. "Comprising" is a technical term used in claim language, meaning that the elements exist, but other elements can also be added and still form a structure or method within the scope of the claims.

[0024] It should be noted that like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance. The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope of protection of this application.

[0025] Referring to "embodiments" herein means that specific features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appears in various places in the description and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0026] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] A cooling solution for a low-voltage cabinet includes a cabinet body 1, a busbar chamber 6 is arranged inside the cabinet body 1, and a pressure relief chamber 3 is further arranged above the busbar chamber 6. A busbar 2, an electromagnetic detection device 5, an electromagnetic suppression device 10, and a heat dissipation module are arranged inside the busbar chamber 6, as Figure 1 shown.

[0028] The electromagnetic detection device 5 is arranged on the side wall of the cabinet body 1 of the busbar chamber 6, and its output end is connected to the input unit of the main control unit, and is used to detect the magnitude and direction of the magnetic field inside the cabinet body 1. Further, at least 3 electromagnetic detection devices 5 are included, which are respectively arranged on different side walls and are used to detect the magnetic fields received by each side wall. In some embodiments, at least 2 of the electromagnetic detection devices 5 are arranged on each side wall, and the 2 electromagnetic detection devices 5 are located in different orientations. By combining the data of the electromagnetic detection devices 5 on multiple side walls of the cabinet body 1, a three-dimensional magnetic field distribution state is constructed, so as to analyze the parts of the cabinet body 1 vulnerable to eddy current loss, and provide a reference for the further protection control of the subsequent cabinet body 1, asFigure 2 as shown

[0029] The heat dissipation module is arranged on the top of the busbar bin 6 and in the pressure relief chamber 3. It includes daily heat dissipation equipment and emergency heat dissipation equipment 7. The daily heat dissipation equipment is a fan, and the emergency heat dissipation equipment 7 includes a film cooling module 72. The film cooling module 72 is located below the top plate of the busbar bin 6. A cooling cavity 73 is arranged downward on the side of the top plate of the busbar bin 6 biased towards the bus connection. The film cooling module 72 is arranged in the cooling cavity 73. When the signal detected by the electromagnetic detection device 5 exceeds the threshold, the film cooling module 72 is started for emergency cooling to prevent the components in the cabinet from being affected by the suddenly rising high temperature and affecting their reliability and safety.

[0030] An air inlet channel 43 and an air outlet channel 44 are arranged in the pressure relief chamber. An isolation is formed between the air inlet channel 43 and the air outlet channel 44 to prevent the inlet air flow and the discharged air flow from circulating or mixing in the pressure relief chamber. An air inlet 41 is formed on the side wall of the pressure relief chamber connected to the air inlet channel 43, and an air outlet 42 is formed on the side wall of the pressure relief chamber connected to the air outlet channel 44. Further, the air inlet 41 and the air outlet 42 are not simultaneously arranged on the same side wall, as Figure 6 as shown

[0031] In some embodiments, a first fan 71 is further arranged above the cooling cavity 73. The first fan 71 is arranged in the air inlet channel 43. The first fan 71 sucks external air into the cabinet 1 through the air inlet 41 and introduces it into the film cooling module 72. The air is cooled and accelerated by the film cooling module 72, and the accelerated cooled air enters the cabinet and convects with the hot air, thereby improving the heat dissipation speed.

[0032] Further, a dust filter is also arranged at the air inlet 41 of the heat dissipation module. In some embodiments, the dust filter can be arranged between the first fan 71 and the film cooling module 72, and the dust filter can be a micro-porous filter paper treated with resin and horizontally arranged above the cooling cavity 73. In other embodiments, the dust filter can also be arranged on the end face of the air inlet 41 of the first fan 71.

[0033] The daily heat dissipation module includes at least two second fans 8. The second fans 8 are arranged in the air outlet channel 44 and are respectively arranged on both sides of the first fan 71 to extract the hot air in the cabinet 1 through the air outlet 42.

[0034] The film cooling module 72 includes a cooling cavity 73. A phase change material 75 is arranged in the cooling cavity 73. After being excited by the main control unit to be energized, it refrigerates, thereby forming cold air in the cooling cavity 73.

[0035] Further, the side wall of the cooling cavity 73 has a certain inclined arc, such that the cross-sectional area at the bottom end of the cooling cavity 73 is larger than that at the upper end, as Figure 3 shown.

[0036] Further, in some embodiments, the phase change material 75 is a ferromagnetic phase change material 75, and refrigeration occurs during the process of ferromagnetic material turning into paramagnetic material. This process is achieved through the magnetocaloric effect. The magnetocaloric effect refers to the effect that the temperature of an object changes with its magnetism. Specifically, when a ferromagnetic material changes from ferromagnetic to paramagnetic under the action of an external magnetic field, heat is released, thereby causing the temperature of the surrounding environment to drop, achieving the refrigeration effect. Specifically, the ferromagnetic material is located in the refrigeration cavity. The ferromagnetic material is a wound coil, and the electrodes of the coil are connected to the main control unit. The main control unit controls the start and stop of the pulsed current. The material with ferromagnetic properties is changed into a paramagnetic material by the pulsed current method for refrigeration. After the refrigeration is completed, the material is remagnetized in the magnetic field inside the cabinet to prepare for the next refrigeration.

[0037] Further, the phase change material 75 has a woven structure, and the woven structure adheres to the inner wall of the cooling cavity 73 in a manner that is prone to deformation, forming a cooling film structure with a large area. It achieves the technical effect of being convenient to adapt to the shape of the cooling cavity 73, thus simplifying the installation. At the same time, it also has the effect of large-area contact and cooling of air, improving the cooling efficiency, as Figure 3 shown.

[0038] In some other embodiments, the phase change material 75 has a woven structure and has voids that facilitate ventilation. The phase change material 75 forms a disc-shaped structure and is clamped in the space of the cooling cavity 73. The shape of the phase change material 75 is consistent with the cross-sectional shape of the cooling cavity 73, as Figure 4 shown. While effectively cooling the air, the usage amount of the material can be reduced, and the cost can be lowered.

[0039] In some embodiments, a bladder 74 is provided in the cooling cavity 73, and the phase change material 75 is disposed in the bladder 74. There is a gap for air circulation between the bladder 74 and the cooling cavity 73, as Figure 5 shown. Specifically, the phase change material 75 is a material containing iron ions. The material is disposed in the bladder 74, and the iron ion thermoelectric refrigeration technology is adopted. Applying an external current to drive an electrochemical reaction can generate cooling energy. This technology is based on an electrochemical oxidation-reduction reaction involving dissolved iron ions. Iron ions lose an electron and absorb heat (Fe3+ → Fe2+).

[0040] In this application, reversible phase change material 75 is used for refrigeration. Compared with traditional air-conditioning refrigeration methods, it has good refrigeration effects, simpler structure, smaller occupied space, and lower cost. The heat dissipation module is divided into daily heat dissipation and emergency heat dissipation, which can protect the switch cabinet from high-temperature damage and effectively reduce the energy consumption of the switch cabinet.

[0041] The bottom wall of the cooling cavity 73 is provided with air holes 76. The bottom wall has a certain thickness, so that the air holes 76 form a channel with a certain depth. The shape of the channel is inclined, consistent with the inclination trend of the cooling cavity 73, and inclined from the center to the periphery. Since the thin film cooling module 72 sinks into the cabinet body 1, and the cross-section of the channel of the air hole 76 is smaller than the upper end surface of the cooling cavity 73, it is equivalent to forming a pressurizing effect of the cooling air flow 91 in the channel. When the thin film cooling module 72 is turned on, the cooling air flow 91 has a certain acceleration, is sprayed at an angle through the air holes 76 towards the bottom of the cabinet body 1, and forms a curved flow path to form a swirl at the end of the air flow, mixes with the surrounding hot air, and after heat exchange in the lower part, the hot air flow 92 is discharged through the second fan on the side. Due to the design of the channel of the air hole 76, the cooling air flow 91 can flow deeper into the lower side of the switch cabinet, cool more electrical components, increase the contact area between the hot and cold air flows 92, and further improve the cooling effect.

[0042] Furthermore, a water-absorbing material is also provided on the bottom wall of the cold cutting cavity. In some embodiments, the water-absorbing material is coated on the inner wall of the air hole 76, such as water-absorbing resin, polyacrylate, etc. In some embodiments, the water-absorbing material can also be used to form the bottom wall material, such as superabsorbent plastics, polyvinyl alcohol, etc., which have good shaping and water-absorbing functions. By setting the water-absorbing material, it is possible to prevent the formation of condensed water during refrigeration, which may damage the safety performance of the switch cabinet.

[0043] Furthermore, this application also includes an electromagnetic suppression device 10. The electromagnetic suppression device 10 generates a reverse magnetic flux according to the magnetic field signal detected by the electromagnetic detection device 5 in real time, so as to suppress the formation of eddy currents of the interference magnetic field in the cabinet body 1. The electromagnetic suppression device 10 has a flat structure and includes a coil device. Its input end is connected to the main control unit. The main control unit calculates the magnitude of the current to be output according to the signal detected by the electromagnetic induction device, and then outputs a reverse current to form a reverse magnetic flux.

[0044] The above has introduced the embodiments of the present application in detail. Specific examples are used in this text to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A cooling solution for a low-voltage cabinet, characterized in that: It includes a cabinet, a busbar, an electromagnetic detection device, an electromagnetic suppression device and a heat dissipation module; The cabinet further comprises a busbar compartment, the busbar is arranged in the busbar compartment, the electromagnetic detection device is arranged on the cabinet side wall of the busbar compartment, the electromagnetic suppression device is arranged on the inner wall surface of the cabinet, and the heat dissipation module is arranged on the top of the busbar compartment; The electromagnetic detection device detects the magnitude and direction of the magnetic field in the cabinet; The electromagnetic suppression device generates a reverse magnetic flux according to the magnetic field signal detected in real time by the electromagnetic detection device, thereby suppressing the interference magnetic field from forming eddy currents in the cabinet; The heat dissipation module includes a film cooling module. When the signal detected by the electromagnetic detection device exceeds a threshold, the film cooling module is activated to perform emergency cooling.

2. The cooling solution for the low-voltage cabinet according to claim 1 is characterized in that: It comprises at least three electromagnetic detection devices, which are respectively arranged on different inner side walls of the cabinet, and the output ends of the electromagnetic detection devices are connected to the input units of the main control unit.

3. The cooling solution for the low-voltage cabinet according to claim 1 is characterized in that: The electromagnetic suppression device is a flat structure, including a coil device, whose input end is connected to the main control unit. The main control unit calculates the current required to be output according to the signal detected by the electromagnetic induction device, thereby outputting a reverse current to form a reverse magnetic flux.

4. The cooling solution for the low-voltage cabinet according to claim 1 is characterized in that: The film cooling module comprises a cooling cavity, in which a phase change material is arranged. The phase change material is refrigerated after being excited, thereby forming cold air in the cooling cavity.

5. The cooling solution for the low-voltage cabinet according to claim 4 is characterized in that: The phase change material performs cooling through magnetocaloric effect or electrochemical reaction.

6. The cooling solution for the low-voltage cabinet according to claim 4 is characterized in that: A capsule is arranged in the cooling cavity, the phase change material is arranged in the capsule, and there is a gap for air circulation between the capsule and the cooling cavity.

7. According to the cooling solution of a low-voltage cabinet as described in claim 4, it is characterized in that: The cabinet also includes a pressure relief cover plate, on which a fan is arranged. The fan includes a first fan for drawing air inwards, and a second fan for drawing air outwards. The first fan is located above the film cooling module.

8. A cooling solution for a low-voltage cabinet according to claim 7, characterized in that: The second fans include two, which are respectively arranged on both sides of the first fan.

9. A cooling solution for a low-voltage cabinet according to claim 8, characterized in that: The bottom wall of the cooling cavity is provided with air holes, the shape of the air hole channel is inclined, and the air hole opening is inclined toward the second fan.

10. A cooling solution for a low-voltage cabinet according to claim 8, characterized in that: The film cooling module sinks into the cabinet. When the film cooling module is turned on, the cooling airflow is dispersedly sprayed toward the bottom of the cabinet through the air holes at a certain angle, and the cooling airflow with an arc is mixed with the hot air, and then the hot airflow is discharged through the second fan.

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