High-voltage protection switch cabinet for open-pit mine

Abstract

The application discloses an outdoor high-voltage protection switch cabinet for open-pit mine, and belongs to the technical field of switch cabinets. According to the application, an annular cavity is formed between an outer shell and the switch cabinet, and an air inlet module of a built-in filter and a positive pressure fan is matched, so that the positive pressure of each chamber is uniform and consistent and the air flow complementary capacity when local blockage is achieved. A buffer platform provides elastic support and attenuates vertical vibration in an overall flat plate structure. A protection assembly is composed of a composite damping mechanism formed by superposition of restoring force of a buffer spring, friction damping force and gas damping force, so as to effectively inhibit the horizontal vibration amplitude, reduce the inertial impact borne by a circuit breaker closing holding mechanism to below a mis-trip threshold, and automatically increase the fan speed when blasting vibration is detected by cooperation of a vibration sensor on the air inlet module and a controller. Through a single speed-up action, three self-adaptive linkages of dustproof positive pressure enhancement, gas damping vibration isolation enhancement and insulation sleeve surface self-cleaning enhancement are simultaneously achieved, so that the coupling deterioration chain between vibration and dust is broken.

Description

Technical Field

[0001] This invention relates to the field of switchgear technology, and in particular to a high-voltage protection switchgear for outdoor open-pit mines. Background Technology

[0002] High-voltage switchgear is a core device in power systems used to control, protect, and isolate high-voltage electrical equipment. In the power supply and distribution system of open-pit mines, it undertakes the functions of high-voltage power supply control and fault protection for mining equipment, transportation equipment, and auxiliary facilities in the mining area. As the mining operation area of ​​open-pit mines continues to advance and change, high-voltage switchgear often needs to be deployed in outdoor sites close to the mining area, and operates in an open environment with high concentration of mine dust and harsh climatic conditions for a long time.

[0003] The frequent and continuous blasting operations in daily open-pit mining pose a dual hazard to high-voltage switchgear deployed near the mining area: Firstly, the high-intensity shock waves generated by blasting are transmitted to the switchgear through the foundation in the form of ground vibration, causing the circuit breaker closing and holding mechanism inside the switchgear to trip due to inertial impact, and the insulation components to loosen due to repeated vibration, resulting in changes in creepage clearance; secondly, the large amount of mine dust raised by blasting spreads rapidly under the drive of air shock waves and remains for a long time. After high concentrations of mine dust enter the interior of the switchgear, they cover the surface of the insulation components, forming conductive channels, which seriously weakens the insulation performance and causes creepage flashover accidents. The above two types of hazards occur superimposed during the blasting period. Vibration damages the creepage path of the insulation components, and dust accelerates the deposition on the damaged creepage path. The two form a coupled deterioration effect. Existing switchgear protection schemes usually treat vibration isolation and dust prevention as two independent issues and fail to identify and deal with the coupling effect between vibration and dust. Therefore, it is difficult to effectively ensure the operational safety of high-voltage switchgear under open-pit blasting conditions. Summary of the Invention

[0004] This invention provides a high-voltage protection switchgear for outdoor open-pit mines, which can solve the problem that the existing switchgear protection schemes usually treat vibration isolation and dust prevention as two independent issues, failing to identify and address the coupling effect between vibration and dust, thus making it difficult to effectively ensure the operational safety of the high-voltage switchgear under open-pit mine blasting conditions.

[0005] An outdoor open-pit mine high-voltage protection switchgear includes: an outer casing with a door on one side and a flow-guiding assembly at the outer end, the flow-guiding assembly including an air inlet module and an air outlet module; a switchgear installed inside the outer casing, with an annular cavity formed between the outer wall of the switchgear and the inner wall of the outer casing, the switchgear consisting of multiple switch chambers, each switch chamber having a guide hole on its wall panel; and a protection assembly disposed between the inner wall of the outer casing and the outer wall of the switchgear, for providing multi-directional elastic buffer support for the switchgear; wherein, the air inlet module is used to supply filtered clean air into the annular cavity, the clean air is distributed through the annular cavity and enters the interior of each switch chamber through the guide holes, and is discharged through the air outlet module, thereby creating a positive pressure clean environment inside the switchgear.

[0006] Preferably, the air intake module is installed on one side of the housing, the air intake module has an air inlet, and the air intake module is equipped with a filter and a positive pressure fan.

[0007] Preferably, a vibration sensor is installed on the air intake module, and a controller is disposed inside the housing. The controller is electrically connected to the vibration sensor and the positive pressure fan, respectively.

[0008] Preferably, multiple switch chambers are arranged in sequence and connected together. Each switch chamber is also provided with an exhaust port. The clean air enters the interior of each switch chamber through the guide hole and is discharged from the exhaust port.

[0009] Preferably, one end of the switch cabinet is equipped with an exhaust chamber that communicates with the switch cabinet, the exhaust chamber is connected to the air outlet module, and the outlet of the switch compartment is connected to the exhaust chamber.

[0010] Preferably, a buffer platform is installed at the bottom of the housing, and the switch cabinet is placed on the buffer platform.

[0011] Preferably, the protection component includes a sealing cylinder installed on the inner wall of the outer casing, a sealing rod slidably connected inside the sealing cylinder, a flexible abutment plate installed at one end of the sealing rod, an elastic airbag installed on one side of the flexible abutment plate, the elastic airbag abutting against the outer wall of the switch cabinet, and the elastic airbag is provided with an air intake port and an air exhaust port, both of which are equipped with one-way valves.

[0012] Preferably, a buffer spring is sleeved on the outside of the sealing rod, and the two ends of the buffer spring are respectively connected to the sealing cylinder and the flexible abutment plate.

[0013] Preferably, the switch cabinet is provided with a plurality of evenly distributed insulating sleeves at its outer end, and the insulating sleeves are provided with a plurality of evenly distributed skirts on their outer sides.

[0014] Preferably, a cushioning pad is installed on the inner wall of the cabinet door.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This solution forms an annular cavity between the outer shell and the switch cabinet, and sets an air intake module with a built-in filter and positive pressure fan on one side of the outer shell to keep the switch cabinet in a clean positive pressure environment to prevent external mine dust from entering. Multiple switch chambers are arranged in series to keep the airflow between adjacent switch chambers connected. Even if a certain guide hole is partially blocked due to vibration, the switch chamber can still obtain airflow supplement through the connection with the adjacent switch chamber without losing positive pressure protection. The exhaust chamber set at the end plays a role in stabilizing and buffering the back pressure of the exhaust outlet of each switch chamber, ensuring that the positive pressure level in each switch chamber is uniform.

[0016] (2) This scheme installs a buffer platform at the bottom of the housing, which provides continuous and uniform elastic support for the switchgear with an overall flat plate structure, effectively attenuating vertical vibration. At the same time, the bottom annular cavity forms a relatively closed airflow buffer zone, which is conducive to the balanced distribution of positive pressure airflow. The protection components apply elastic clamping to the switchgear from multiple directions. The elastic restoring force of the buffer spring, the friction damping force between the sealing cylinder and the sealing rod, and the gas damping force generated by the compressed side of the annular cavity are superimposed to form a composite damping mechanism, which effectively suppresses the vibration amplitude of the switchgear in the horizontal direction, reducing the inertial impact force borne by the circuit breaker closing and holding mechanism to below the false tripping threshold. Meanwhile, the flexible abutment plate and the sealing cylinder always maintain sealed contact during vibration, so that the annular cavity maintains positive pressure and does not leak under dynamic vibration conditions.

[0017] (3) In this scheme, an elastic airbag is installed on the back of the flexible contact plate. The burst vibration itself is used as the driving force source, so that the elastic airbag completes a cycle of compression and exhaust and expansion and intake in each vibration cycle. Since the pumping volume and frequency of the elastic airbag depend entirely on the shaking amplitude and frequency of the switch cabinet, the more intense the vibration, the stronger the dust prevention and air replenishment and vibration isolation buffering effect will be automatically, thus realizing the adaptive matching of protection strength and threat strength. The whole process is purely mechanically passively driven, without the need for sensor or controller intervention. Meanwhile, the elastic airbag adopts an open airbag structure with both intake and exhaust ports instead of a conventional completely sealed airbag. During the compression phase, the gas inside the airbag can be continuously discharged outward through the exhaust port. The gas pressure inside the airbag is always limited within a safe range under the exhaust release effect, and there will be no pressure accumulation due to repeated compression. Even under the most severe vibration conditions, the internal pressure that the airbag bears is far below its material ultimate strength, preventing the risk of the sealed airbag bursting and failing due to a sharp increase in internal pressure. This ensures the structural reliability and long service life of the elastic airbag under extreme conditions. In addition, the asymmetrical design of the exhaust port diameter being much smaller than the intake port diameter gives the exhaust process a certain throttling resistance. This ensures that the airbag generates sufficient gas back pressure reaction force during the compression phase to achieve a damping buffering effect, while avoiding the instantaneous exhaust of gas and loss of buffering capacity. A reasonable balance is achieved between safe pressure relief and buffering effectiveness. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the switch cabinet housing provided by the present invention; Figure 2 This is a three-dimensional structural diagram of the side of the switch cabinet housing provided by the present invention; Figure 3 This is a three-dimensional structural diagram of the internal structure of the switch cabinet housing provided by the present invention; Figure 4 A three-dimensional structural diagram of the protective component provided by the present invention; Figure 5 This is a three-dimensional structural diagram of the switch cabinet provided by the present invention; Figure 6 A three-dimensional structural diagram of the insulating sleeve provided by the present invention; Figure 7 This is a schematic diagram of the three-dimensional structure of the umbrella skirt provided by the present invention.

[0019] Explanation of reference numerals in the attached figures: 1. Housing; 2. Switch cabinet; 3. Protection components; 11. Air inlet module; 12. Air outlet module; 13. Cabinet door; 14. Buffer platform; 15. Exhaust chamber; 21. Switch compartment; 22. Insulating sleeve; 23. Umbrella skirt; 31. Sealing cylinder; 32. Sealing rod; 33. Flexible abutment plate. Detailed Implementation

[0020] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0021] like Figures 1 to 4 As shown in the figure, an outdoor open-pit mine high-voltage protection switchgear provided by this embodiment of the invention includes: an outer shell 1, with a cabinet door 13 installed on one side of the outer shell 1, and a flow guiding component provided at the outer end of the outer shell 1, the flow guiding component including an air inlet module 11 and an air outlet module 12; a switchgear 2, which is installed inside the outer shell 1, and an annular cavity is formed between the outer wall of the switchgear 2 and the inner wall of the outer shell 1, the switchgear 2 is composed of multiple switch chambers 21, and a flow guiding hole is opened on the wall panel of each switch chamber 21; a protection component 3, which is disposed between the inner wall of the outer shell 1 and the outer wall of the switchgear 2, and is used to provide multi-directional elastic buffer support for the switchgear 2; wherein, the air inlet module 11 is used to send filtered clean air into the annular cavity, the clean air is distributed through the annular cavity and enters the interior of each switch chamber 21 through the flow guiding hole, and is discharged through the air outlet module 12, so as to form a positive pressure clean environment inside the switchgear 2.

[0022] An air intake module 11 is installed on one side of the outer casing 1. An air intake port is provided on the air intake module 11, and a filter and a positive pressure fan are installed inside the air intake module 11. A vibration sensor is installed on the air intake module 11, and a controller is provided inside the outer casing 1. The controller is electrically connected to the vibration sensor and the positive pressure fan respectively.

[0023] Multiple switch chambers 21 are connected in sequence. Each switch chamber 21 is also provided with an exhaust port. Clean air enters the interior of each switch chamber 21 through the guide hole and is discharged from the exhaust port. One end of the switch cabinet 2 is equipped with an exhaust cavity 15 that is connected to the switch cabinet. The exhaust cavity 15 is connected to the air outlet module 12. The exhaust port of the switch chamber 21 is connected to the exhaust cavity 15.

[0024] Among them, the high-intensity shock wave generated by the blasting operation in the open mine acts on the switch cabinet 2 deployed near the mining area simultaneously through two paths: surface vibration and air shock wave. The surface vibration is transmitted to the outer shell 1 through the foundation. Moreover, the blasting operation is continuous, which will cause the outer shell 1 and the switch cabinet 2 inside to vibrate continuously. This vibration causes the closing and holding mechanism of the circuit breaker in the switch room 21 to be subjected to inertial impact and to trip erroneously. At the same time, the insulation components loosen due to repeated vibration and the creepage gap changes.

[0025] At the same time, the large amount of mine dust raised by the blast spread rapidly and remained for a long time under the drive of the air shock wave. The high concentration of mine dust continued to invade the interior of the switch chamber 21 and covered the surface of the insulating parts to form conductive channels, which seriously weakened the insulation performance and eventually led to a creepage flashover accident.

[0026] The two types of hazards mentioned above occur simultaneously during blasting. Vibration damages the creepage path of insulation components, and dust accumulates more rapidly on the damaged creepage path. The two create a coupled and deteriorating effect. Existing switchgear protection solutions usually treat vibration isolation and dust prevention separately, failing to identify and address this coupled effect. Therefore, it is difficult to effectively ensure the safety of electrical equipment under open-pit mine blasting conditions.

[0027] To address the aforementioned issues, the present invention provides an air intake module 11 on one side of the outer casing 1. The air intake module 11 is installed on the side wall of the outer casing 1 as an independent functional module. The air intake module 11 has an air inlet as the only entrance for external air to enter the system. Inside the air intake module 11, a filter and a positive pressure fan are installed sequentially along the air intake direction. After the external air passes through the filter to remove mineral dust particles, it is pressurized by the positive pressure fan to form a clean positive pressure airflow.

[0028] A vibration sensor is also installed on the air intake module 11. A controller is installed inside the housing 1. The controller is electrically connected to the vibration sensor and the positive pressure fan respectively. The vibration sensor collects the vibration acceleration signal of the housing 1 in real time and transmits it to the controller. The controller adjusts the speed of the positive pressure fan in real time according to the amplitude change of the vibration signal.

[0029] The vibration sensor is placed on the air intake module 11 rather than on the outer casing 1 body because the air intake module 11 is rigidly installed on the side wall of the outer casing 1 without any elastic buffer between it and the outer casing 1. Therefore, the vibration response on the air intake module 11 is completely consistent with that on the outer casing 1, which can accurately reflect the vibration level transmitted from the foundation to the cabinet. At the same time, the air intake module 11 is located outside the outer casing 1, away from the electromagnetic interference source generated by the operation of internal electrical equipment, which is conducive to the vibration sensor obtaining a purer vibration signal and improving the accuracy of the controller's judgment.

[0030] The interior of the switch cabinet 2 is divided into multiple switch chambers 21 by partitions. These switch chambers 21 are sequentially connected along the airflow direction to form a series airflow channel. The annular cavity formed between the inner wall of the outer casing 1 and the outer wall of the switch cabinet 2 guides the clean positive pressure airflow output from the air inlet module 11 to the perimeter of the switch cabinet 2. The wall panel of the switch cabinet 2 has guide holes at the positions corresponding to each switch chamber 21. The clean air in the annular cavity is distributed into the corresponding switch chamber 21 through the guide holes, so that the interior of each switch chamber 21 is continuously maintained at a positive pressure higher than that of the external environment.

[0031] Since the air pressure inside each switch chamber 21 is always higher than the air pressure outside the outer casing 1, the airflow direction is forced to be maintained from the inside to the outside at all potential leakage locations such as structural gaps, cable penetration holes and cabinet door joints in the switch cabinet 2. Under the action of pressure difference, external dusty air cannot seep into the switch chamber 21 through the above path, thus forming a complete positive pressure airflow barrier around each switch chamber 21, achieving continuous isolation of mine dust.

[0032] Each switch chamber 21 is also equipped with an exhaust port, through which the positive pressure airflow in each switch chamber 21 continuously overflows, maintaining the continuity of the positive pressure circulation of the system. One end of the switch cabinet 2 is equipped with an exhaust chamber 15 connected to the switch cabinet. The exhaust port of each switch chamber 21 is connected to the exhaust chamber 15. The exhaust chamber 15 serves as a collection channel to collect the overflowing airflow from each switch chamber 21. The exhaust chamber 15 is connected to the air outlet module 12, and the airflow is finally discharged to the outside of the outer casing 1 through the air outlet module 12, completing the unidirectional positive pressure airflow circulation from the air inlet module 11 to the air outlet module 12.

[0033] The one-way air path ensures that the air pressure at any point inside the system is higher than that of the external environment. Even if the outer casing 1 experiences a decline in local sealing performance due to long-term use, the existence of the positive pressure difference can still ensure that the leakage direction is always from the inside to the outside, eliminating the driving force for dust to enter from the outside to the inside.

[0034] Because each switch chamber 21 adopts a near-sealed structure design to achieve dust isolation, the switch equipment inside the switch chamber 21 continuously generates heat during operation. If there is no gas flow path, the heat in the sealed space will continue to accumulate, causing the temperature to rise continuously, affecting the performance of the insulation components and the service life of the switch equipment.

[0035] This invention uses a method of maintaining a slight positive pressure to block dust. The airflow velocity entering each switch chamber 21 is extremely low, which does not generate additional dynamic pressure load or aerodynamic vibration on the internal equipment and structural components. It does not interfere with the vibration isolation function of the gas spring in the annular cavity. If a high-speed blowing method is used for dust removal, the required airflow pressure will create continuous turbulent vibration on the internal structure of the switch chamber 21, which contradicts the vibration isolation and protection target.

[0036] By setting up the positive pressure air path, the present invention allows filtered and purified clean air to continuously enter the interior of each sealed switch chamber 21 at a controlled flow rate, thus maintaining the positive pressure barrier and providing a unique convective heat exchange path for the heating components in the sealed space.

[0037] After the clean air entering the switch chamber 21 absorbs the heat, it flows out through the exhaust port. The heat is carried by the airflow through the exhaust cavity 15 and the air outlet module 12 and finally dissipated to the external environment of the outer casing 1, thereby achieving continuous heat dissipation inside the switch chamber 21 without compromising the sealing and dustproof effect.

[0038] This design allows the positive pressure dustproof function and the sealed heat dissipation function to share the same airflow path, eliminating the need for additional heat dissipation ducts or holes. This avoids introducing new dust intrusion channels by adding heat dissipation openings, thus achieving a unified dustproof seal and equipment heat dissipation.

[0039] This structure forms a complete unidirectional airflow path from the air inlet module 11 to the annular cavity, the guide hole, the switch chamber 21, the outlet, the exhaust chamber 15, and the air outlet module 12. Clean air enters from the single inlet, pressurizes all the switch chambers 21 in sequence, and then exits from the single outlet. There are no short circuits or dead zones in the entire air path.

[0040] The reason why the above structure uses a series connection of multiple switch chambers 21 instead of a parallel connection of independent air intake and exhaust is that the series connection ensures that the airflow between adjacent switch chambers 21 is always uninterrupted. Even if a certain guide hole is partially blocked or the flow rate decreases due to vibration, the switch chamber 21 can still obtain airflow supplement through the connection between it and the adjacent switch chamber 21, and there will be no situation where a switch chamber 21 completely loses positive pressure protection. If each switch room 21 adopts parallel independent air supply, once a branch is blocked, the room will lose positive pressure and become a weak point for dust intrusion.

[0041] In addition, the series connection structure allows all switch chambers 21 to share the same main airflow path, and the air pressure in each switch chamber 21 is automatically balanced through the connection port. This eliminates the need for precise flow distribution calculations for the area of ​​the guide holes in each switch chamber 21, reducing design and manufacturing difficulty.

[0042] An independent exhaust chamber 15 is set at the end of the air path as a collection and buffer space to avoid mutual interference of the air paths caused by the direct connection of the exhaust outlet of each switch chamber 21 to the air outlet module 12. The volume of the exhaust chamber 15 plays a role in stabilizing and buffering the exhaust airflow, ensuring that the back pressure at the exhaust outlet of each switch chamber 21 is uniform, thereby ensuring that the positive pressure level in each switch chamber 21 is uniform.

[0043] When the controller receives a vibration acceleration signal from the vibration sensor that exceeds a preset threshold, it determines that an explosion vibration event has occurred. The controller then increases the speed of the positive pressure fan to increase the supply flow and pressure of clean air.

[0044] As the fan speed increases, the air pressure inside the annular cavity rises, which on the one hand increases the positive pressure level inside each switch chamber 21, enhancing the ability to suppress high-concentration blasting dust from the outside, and preventing dust from invading the switch chamber 21 during the instantaneous pressure fluctuations caused by the blast shock wave.

[0045] On the other hand, the increase in air pressure inside the annular cavity means that when the switch cabinet 2 undergoes a slight displacement relative to the outer shell 1 due to vibration, the air pressure inside the compressed cavity increases more significantly, resulting in a stronger reverse gas damping force and a more significant vibration suppression effect on the switch cabinet 2.

[0046] During the blasting process, the moment with the highest dust concentration is also the moment with the strongest vibration. The controller enhances both the dustproof positive pressure and vibration damping protection functions simultaneously through a single fan speed-up action. This allows dustproofing and vibration isolation to automatically achieve coordinated enhancement at the moment when they are most needed. This is the coupled protection effect produced by integrating the vibration isolation structure and the positive pressure air supply structure into the same annular cavity, which cannot be achieved by separately set vibration isolation systems and dustproof systems.

[0047] like Figures 4 to 7 As shown, a buffer platform 14 is installed at the bottom inside the outer casing 1, and the switch cabinet 2 is placed on the buffer platform 14.

[0048] The protection component 3 includes a sealing cylinder 31 installed on the inner wall of the outer casing 1. A sealing rod 32 is slidably connected inside the sealing cylinder 31. A flexible abutment plate 33 is installed at one end of the sealing rod 32. An elastic airbag is installed on one side of the flexible abutment plate 33. The elastic airbag abuts against the outer wall of the switch cabinet 2. The elastic airbag is provided with an air intake port and an air exhaust port. A one-way valve is installed in both the air intake port and the air exhaust port. A buffer spring 34 is sleeved on the outside of the sealing rod 32. The two ends of the buffer spring 34 are connected to the sealing cylinder 31 and the flexible abutment plate 33, respectively.

[0049] The way the switch cabinet 2 is supported inside the outer casing 1 directly determines the vibration isolation effect and airflow sealing performance.

[0050] If the switch cabinet 2 is rigidly fixed to the bottom plate of the outer shell 1, the ground vibration will be directly transmitted to the switch cabinet 2 without attenuation through the bottom plate of the outer shell 1. Although there is an annular cavity between the outer shell 1 and the switch cabinet 2 to distribute positive pressure airflow, the cavity does not play any buffering role in the vibration transmission path. The vibration isolation and dust prevention functions are still operating independently and have failed to form a coupled synergistic effect.

[0051] To this end, a buffer platform 14 is installed at the bottom of the inner casing 1, and the switchgear 2 is placed on the buffer platform 14. The buffer platform 14 serves as an elastic transition layer between the switchgear 2 and the bottom plate of the outer casing 1, bearing the full weight of the switchgear 2 while attenuating vertical vibrations. When ground vibrations are transmitted to the buffer platform 14 through the bottom plate of the outer casing 1, the elastic deformation of the buffer platform 14 absorbs the vibration energy and reduces the peak vibration acceleration transmitted to the switchgear 2, thereby reducing the inertial impact force borne by the circuit breaker closing and holding mechanism inside the switchgear 2 to below the false tripping threshold.

[0052] The buffer platform 14 adopts an integral flat plate structure that covers most of the bottom plate area of ​​the outer shell 1. Compared with the point support method, the flat plate buffer platform 14 provides a continuous and uniform support surface for the switch cabinet 2, avoiding the tendency of the switch cabinet 2 to swing or overturn due to uneven force on local support points during vibration. At the same time, the overall plane of the buffer platform 14 separates the annular cavity at the bottom of the outer shell 1 from the bottom of the switch cabinet 2, so that the bottom cavity forms a relatively closed airflow buffer zone. After the positive pressure clean air enters the bottom cavity, it is constrained by the edge of the buffer platform 14 and diffuses evenly in all directions, which is conducive to the balanced distribution of air pressure in the annular cavity.

[0053] However, the buffer platform 14 only solves the problem of vertical vibration transmission. The surface vibration generated by open-pit mine blasting includes vertical and horizontal components, and the amplitude of the horizontal component is often greater than that of the vertical component. After the switch cabinet 2 is placed on the buffer platform 14, it is in an unconstrained state in the horizontal direction. Horizontal vibration will cause the switch cabinet 2 to slide and sway horizontally on the buffer platform 14, which not only threatens the safety of internal electrical components, but also causes the annular cavity distance between the outer wall of the switch cabinet 2 and the inner wall of the outer shell 1 to change continuously. When the local distance is too small, the airflow is obstructed; when the local distance is too large, the airflow is short-circuited, and the uniform distribution of positive pressure airflow is destroyed.

[0054] More seriously, the large horizontal swaying of switch cabinet 2 may cause direct collision between its outer wall and the inner wall of the outer casing 1. The impact acceleration generated by the collision is much greater than the original vibration acceleration, causing secondary damage to the electrical components inside the switch chamber 21.

[0055] Therefore, it is necessary to apply flexible constraints to the switch cabinet 2 in the horizontal direction. These constraints must limit the horizontal displacement of the switch cabinet 2 to prevent collisions and airflow turbulence, while maintaining sufficient elastic deformation capacity to avoid rigidly transmitting horizontal vibrations to the switch cabinet 2.

[0056] Therefore, the protection component 3 includes a sealing cylinder 31 installed on the inner wall of the outer casing 1. A sealing rod 32 is slidably connected inside the sealing cylinder 31. A flexible abutment plate 33 is installed at one end of the sealing rod 32. The flexible abutment plate 33 abuts against the outer wall of the switch cabinet 2. A buffer spring 34 is sleeved on the outside of the sealing rod 32. The two ends of the buffer spring 34 are connected to the sealing cylinder 31 and the flexible abutment plate 33, respectively.

[0057] The protection components 3 are distributed along the inner wall of the outer shell 1 in multiple directions, forming an elastic clamping of the switch cabinet 2 in all directions in the horizontal plane. Under normal conditions without vibration, the buffer spring 34 is in a pre-compressed state, and the flexible abutment plate 33 is continuously pressed against the outer wall of the switch cabinet 2 through the sealing rod 32. The spring pre-tensioning forces of the protection components 3 in each direction are balanced with each other, and the switch cabinet 2 is stably constrained to the center position of the outer shell 1.

[0058] When horizontal vibration occurs, the switchgear 2 is displaced in a certain direction. The buffer spring 34 in the protection component 3 in that direction is further compressed, and the sealing rod 32 slides outward in the sealing cylinder 31. The compression stroke generates an increasing elastic restoring force that pushes the switchgear 2 back to the center position. At the same time, the buffer spring 34 in the protection component 3 in the opposite direction is stretched and released. Under the action of the spring's rebound force, the flexible abutment plate 33 always follows the outer wall of the switchgear 2 without losing contact.

[0059] During the sliding process of the sealing rod 32 inside the sealing cylinder 31, the friction between the sealing cylinder 31 and the sealing rod 32 provides sliding damping. This damping converts the vibration kinetic energy into frictional heat dissipation. Together with the elastic energy storage and release of the buffer spring 34, it constitutes a spring-damping vibration reduction system, which effectively suppresses the horizontal vibration amplitude of the switch cabinet 2.

[0060] While achieving horizontal vibration isolation, the protective component 3 also undertakes the dynamic sealing function of the annular cavity. The flexible abutment plate 33 and the outer wall of the switch cabinet 2 are in flexible surface contact. The flexible material of the flexible abutment plate 33 allows it to conform to the surface contour of the outer wall of the switch cabinet 2. When the switch cabinet 2 experiences slight vibration displacement, the flexible abutment plate 33 deforms accordingly and always maintains a tight fit with the outer wall of the switch cabinet 2 without creating gaps.

[0061] The part where the sealing rod 32 passes through the sealing cylinder 31 also forms a sliding seal. The elastic material of the sealing cylinder 31 wraps around the outer surface of the sealing rod 32, and the sealing contact is always maintained during the sliding process of the sealing rod 32.

[0062] The two seals mentioned above together isolate the annular cavity from the external environment, preventing positive pressure clean air from leaking to the outside from the location of the protective component 3, and ensuring that a stable positive pressure level is maintained in the annular cavity.

[0063] Under vibration conditions, the slight displacement of switchgear 2 causes one side of the annular cavity to be compressed and the other side to be stretched. Since the protection component 3 is sealed on both sides, the air in the compressed cavity will not escape through the gap of the protection component 3, thus generating a significant increase in air pressure and forming a gas damping force opposite to the vibration direction. This gas damping force, together with the elastic restoring force of the buffer spring 34 and the frictional damping force between the sealing cylinder 31 and the sealing rod 32, constitutes the composite damping suppression mechanism of the protection component 3 against the horizontal vibration of switchgear 2.

[0064] When blasting operations in an open-pit mine generate impact vibrations, switchgear 2 shakes significantly within its outer casing 1. As switchgear 2 shakes towards the flexible contact plate 33, the contact pressure suddenly increases, further pressing the flexible contact plate 33 inward. This causes the elastic airbag to contract under pressure, reducing its volume. Since the exhaust port diameter of the elastic airbag is much smaller than the intake port diameter, and both the intake and exhaust ports are equipped with one-way valves, the gas inside the elastic airbag can only be slowly squeezed out through the small-diameter exhaust port during the contraction process. The back pressure generated by the exhaust resistance causes the gas pressure inside the elastic airbag to rise instantaneously. This pressure increase process applies a gas reaction force opposite to the compression direction to the flexible contact plate 33. Together with the elastic restoring force of the buffer spring 34, this force decelerates and buffers the impact displacement of switchgear 2. The clean gas squeezed out through the exhaust port is sprayed in the form of a low-speed jet onto the vicinity of the outer wall surface of switchgear 2, forming a local positive pressure air curtain on the wall surface.

[0065] When switchgear 2 swings back, the contact pressure decreases, and the flexible abutment plate 33 rebounds under the restoring force of the buffer spring 34. The elastic airbag expands and returns to its original shape due to the inherent elastic recovery characteristics of its own rubber or silicone material. The increased volume of the elastic airbag creates a negative pressure inside. Since the diameter of the air intake is much larger than the diameter of the air exhaust, the external gas is preferentially drawn into the airbag from the annular cavity through the large-diameter air intake to complete the inflation and complete a complete air intake-exhaust cycle.

[0066] Under normal low-vibration conditions without explosions, the sway amplitude of switchgear 2 is minimal, the indentation of flexible contact plate 33 is slight, the volume change of elastic airbag is limited, and the annular cavity maintains a normal positive pressure level at this time. The gas pressure that can be obtained when the elastic airbag expands and draws in air is low. Therefore, the pumping effect is not significant, and the elastic airbag is basically in a silent standby state, which does not significantly interfere with the airflow distribution of the system.

[0067] When blasting operations cause continuous and severe vibrations, the amplitude and frequency of the swaying of switchgear 2 increase significantly. The compression stroke of the elastic airbag increases in each vibration cycle. At the same time, the controller increases the speed of the positive pressure fan during the blasting period, which raises the background air pressure in the annular cavity. Each time the elastic airbag expands and draws air, the clean air pressure obtained from the annular cavity is higher and the inflation volume is larger. During subsequent compression and exhaust, the airflow ejected from the exhaust port has a stronger pushing force. The clean air flow rate delivered to the outer wall of switchgear 2 automatically increases with the synchronous increase of vibration intensity and system positive pressure level. Thus, it automatically provides the strongest positive pressure air replenishment protection during the period when the dust concentration of blasting is the highest and the threat of dust intrusion is the greatest, achieving adaptive matching between protection strength and threat strength without the need for additional sensors or control logic intervention.

[0068] It should be noted that the reason why the elastic airbag adopts a structure that is fixed to the back of the flexible abutment plate 33 and indirectly bears pressure through the sealing rod 32 and the buffer spring 34, instead of being independently set in the annular cavity between the outer wall of the switch cabinet 2 and the inner wall of the outer shell 1, is that the vibration impact force of the switch cabinet 2 under the explosion condition has the characteristics of high transient peak value and uncertain direction. If the airbag is independently arranged in the annular cavity to directly bear the compression of the outer wall of the switch cabinet 2, the distance between the outer wall of the switch cabinet 2 and the inner wall of the outer shell 1 will be drastically reduced during violent vibration. The airbag will be subjected to almost rigid opposing compression. The local stress concentration of the airbag is very likely to exceed the material's ultimate strength and cause the airbag to rupture and fail.

[0069] It should be noted that the reason why the elastic airbag adopts an open airbag structure with an air intake and an air exhaust port, instead of using a conventional completely sealed airbag, is that the vibration and impact of the switchgear 2 under the blasting condition has the characteristics of high transient peak value and repeated continuous vibration.

[0070] If a completely sealed airbag is used, the gas inside the airbag has nowhere to escape when it is compressed. The air pressure inside the airbag rises sharply as the compression increases. Especially when a violent explosion causes large-amplitude high-frequency vibration, the sealed airbag is repeatedly and deeply compressed in a short period of time. The internal air pressure continues to accumulate and is very likely to exceed the pressure bearing limit of the airbag material, causing the airbag wall to burst and fail. Once the airbag ruptures, the buffering and pumping functions are lost at the same time.

[0071] In this design, the elastic airbag is equipped with an air intake and an air exhaust port. During the compression phase, the gas inside the airbag can be continuously discharged outward through the exhaust port. The air pressure inside the airbag is always limited to a safe range under the action of exhaust and release, and there will be no pressure accumulation due to repeated compression. Even under the most severe vibration conditions, the internal pressure borne by the airbag is far below the ultimate strength of its material, eliminating the risk of bursting.

[0072] Meanwhile, the asymmetrical design of the exhaust port diameter being much smaller than the intake port diameter creates a certain throttling resistance during the exhaust process. This ensures that the bladder generates sufficient back pressure reaction force during the compression phase to achieve a damping buffering effect, while also preventing the gas from being completely depleted and losing its buffering capacity. A reasonable balance is achieved between safe pressure relief and buffering effectiveness.

[0073] When the controller increases the speed of the positive pressure fan during the blasting period, thereby increasing the air pressure in the annular cavity, the contribution of the gas damping force further increases, and the comprehensive damping performance of the protection component 3 is adaptively enhanced, realizing the linkage and coordination between the positive pressure dustproof system and the horizontal vibration isolation system during the peak blasting period.

[0074] Multiple evenly distributed insulating sleeves 22 are installed on the outer end of the switch cabinet 2, and multiple evenly distributed umbrella skirts 23 are fitted on the outer side of the insulating sleeves 22. A buffer pad is installed on the inner wall of the cabinet door 13.

[0075] Among them, multiple evenly distributed insulating sleeves 22 are installed on the outer end of the switch cabinet 2. The insulating sleeves 22 extend outward through the wall panel of the switch cabinet 2 to realize the electrical connection between the internal live conductor and the external cable.

[0076] Multiple uniformly distributed umbrella skirts 23 are fitted on the outside of the insulating sleeve 22. The umbrella skirts 23 adopt an alternating arrangement of large and small diameters, that is, large diameter umbrella skirts and small diameter umbrella skirts are arranged alternately along the axial direction of the insulating sleeve 22. The radial extension distance of the large diameter umbrella skirt is greater than that of the small diameter umbrella skirt. The alternating arrangement of the two creates a tortuous creepage path of unequal width between adjacent umbrella skirts.

[0077] Compared to equal-diameter umbrella skirts, the creepage distance along the surface is further increased. At the same time, the large-diameter umbrella skirt shields the small-diameter umbrella skirt below, effectively preventing rainwater from flowing directly along the surface of the insulating sleeve 22 to the small-diameter umbrella skirt area, reducing the risk of rainwater and dust mixing on the umbrella skirt surface to form a conductive dirt layer.

[0078] The insulating sleeve 22 also integrates heating elements and condition monitoring sensors. The heating elements are attached to the root area of ​​the umbrella skirt 23 on the outer wall of the insulating sleeve 22. When energized in humid or rainy conditions, they generate heat to evaporate and dry the residual water film on the surface of the insulating sleeve 22 and in the groove of the umbrella skirt 23. To prevent water film from combining with deposited dust to form a continuous conductive channel and causing creepage flashover, a condition monitoring sensor is used to collect the temperature, humidity and leakage current signals on the surface of the insulating sleeve 22 in real time and feed the data back to the controller. The controller judges the dirt status of the insulating sleeve 22 based on this data. When the dirt level or humidity exceeds the set threshold, the heating element is automatically activated to actively dehumidify, thereby realizing intelligent monitoring and adaptive maintenance of the surface status of the insulating sleeve 22.

[0079] The inner wall of the cabinet door 13 is equipped with a buffer pad, which provides a flexible buffer against possible contact and collision between the front face of the switch cabinet 2 and the cabinet door 13 under vibration conditions, transforming rigid impact into progressive elastic contact and reducing the peak value of impact acceleration. At the same time, the buffer pad provides an auxiliary sealing effect on the edge gaps of the cabinet door 13, reducing the disorderly leakage of positive pressure airflow in the annular cavity.

[0080] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. An outdoor open-pit mine high-voltage protection switchgear, characterized in that, include: The outer shell (1) has a cabinet door (13) installed on one side, and a flow-guiding component is provided at the outer end of the outer shell (1). The flow-guiding component includes an air inlet module (11) and an air outlet module (12). Switch cabinet (2), the switch cabinet (2) is installed inside the outer shell (1), and an annular cavity is formed between the outer wall surface of the switch cabinet (2) and the inner wall surface of the outer shell (1). The switch cabinet (2) is composed of multiple switch chambers (21), and each switch chamber (21) has a guide hole on its wall panel. The protective component (3) is disposed between the inner wall of the outer shell (1) and the outer wall of the switch cabinet (2) for providing multi-directional elastic buffer support for the switch cabinet (2); The air inlet module (11) is used to send filtered clean air into the annular cavity. The clean air is distributed through the annular cavity and enters the interior of each switch chamber (21) through the guide hole, and is discharged through the air outlet module (12) to form a positive pressure clean environment inside the switch cabinet (2).

2. The outdoor open-pit mine high-voltage protection switchgear as described in claim 1, characterized in that, The air intake module (11) is installed on one side of the outer casing (1). The air intake module (11) has an air inlet and a filter and a positive pressure fan are installed inside the air intake module (11).

3. The outdoor open-pit mine high-voltage protection switchgear as described in claim 2, characterized in that, A vibration sensor is installed on the air intake module (11), and a controller is provided inside the outer casing (1). The controller is electrically connected to the vibration sensor and the positive pressure fan respectively.

4. The outdoor open-pit mine high-voltage protection switchgear as described in claim 1, characterized in that, Multiple switch chambers (21) are connected in sequence. Each switch chamber (21) is also provided with an exhaust port. The clean air enters the interior of each switch chamber (21) through the guide hole and is discharged from the exhaust port.

5. The outdoor open-pit mine high-voltage protection switchgear as described in claim 4, characterized in that, One end of the switch cabinet (2) is equipped with an exhaust cavity (15) that is connected to the switch cabinet (2). The exhaust cavity (15) is connected to the air outlet module (12). The outlet of the switch chamber (21) is connected to the exhaust cavity (15).

6. The outdoor open-pit mine high-voltage protection switchgear as described in claim 1, characterized in that, A buffer platform (14) is installed at the bottom inside the outer casing (1), and the switch cabinet (2) is placed on the buffer platform (14).

7. The outdoor open-pit mine high-voltage protection switchgear as described in claim 1, characterized in that, The protective component (3) includes a sealing cylinder (31) installed on the inner wall of the outer casing (1). A sealing rod (32) is slidably connected inside the sealing cylinder (31). A flexible abutment plate (33) is installed at one end of the sealing rod (32). An elastic airbag is installed on one side of the flexible abutment plate (33). The elastic airbag abuts against the outer wall of the switch cabinet (2). The elastic airbag is provided with an air intake port and an air exhaust port. A one-way valve is installed in both the air intake port and the air exhaust port.

8. The outdoor open-pit mine high-voltage protection switchgear as described in claim 7, characterized in that, A buffer spring (34) is sleeved on the outside of the sealing rod (32), and the two ends of the buffer spring (34) are connected to the sealing cylinder (31) and the flexible abutment plate (33) respectively.

9. The outdoor open-pit mine high-voltage protection switchgear as described in claim 1, characterized in that, The switch cabinet (2) is equipped with a plurality of evenly distributed insulating sleeves (22) at its outer end, and a plurality of evenly distributed umbrella skirts (23) are fitted on the outer side of the insulating sleeves (22).

10. The outdoor open-pit mine high-voltage protection switchgear as described in claim 1, characterized in that, The inner wall of the cabinet door (13) is equipped with a cushioning pad.

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