A method and device for reducing the resistivity of frozen soil at high altitudes

Abstract

The present invention belongs to the field of photovoltaic module grounding technology, and in particular, relates to a device for reducing the resistivity of high-altitude frozen soil, including: a central conductive rod, a grounding ring is installed on the top of the central conductive rod; the grounding ring is used to connect with the transverse galvanized flat steel; the outer coaxial sleeve of the central conductive rod is provided with a flexible bag or a metal conductive part; the interior of the flexible bag is connected to the central conductive rod, and a method for reducing the resistivity of high-altitude frozen soil based on the above device. Compared with traditional treatment methods, the present invention greatly reduces the construction difficulty, construction costs, and construction period. By injecting a conductive solution into the flexible bag, it can be used as a formwork for the concrete wall in the borehole, and can also be used as a grounding terminal to connect with the photovoltaic module, so as to achieve grounding connection during the construction of the photovoltaic power station and effectively protect the photovoltaic module.

Description

Technical Field

[0001] The present invention belongs to the technical field of photovoltaic module grounding, and in particular relates to a method and a device for reducing the resistivity of frozen soil at high altitudes. Background Art

[0002] With the increasing development of photovoltaic power generation technology, the reliability and safety requirements of the entire photovoltaic system are becoming higher and higher. The grounding of the photovoltaic system is a very important factor affecting the entire photovoltaic power generation system. Therefore, the study of the grounding of the photovoltaic system has great practical significance.

[0003] High-altitude areas are characterized by abundant sunshine, vast land and sparse population, and have the ability to build large-scale photovoltaic power stations. They have been the key areas for photovoltaic development in recent years.

[0004] However, the surface layer of these areas is usually frozen soil, and the moisture in the soil forms a large number of ice crystals under the condition of low temperature all year round. Under the influence of factors such as low temperature and lack of moisture, the resistance of the frozen soil layer is usually between 3000 and 5000Ω, which makes the grounding conductivity of the photovoltaic system poor and it is difficult to meet the grounding requirements of the photovoltaic system.

[0005] In areas with high soil resistivity, the methods for reducing soil resistivity can be summarized as follows:

[0006] (1) Expanding the grounding grid area is not in line with the national policy of saving land, and the effect is not very obvious;

[0007] (2) Use of drag reducing agents is not conducive to environmental protection;

[0008] (3) Laying external grounding electrodes, looking for soil with low resistivity around the photovoltaic system, and then laying grounding electrodes leading to the soil with low resistivity to reduce the total grounding resistance of the grounding grid. This method is not very practical;

[0009] (4) Soil replacement scheme: replacing soil with high resistivity. This approach has high construction costs, and the resistance reduction effect cannot last for a long time as the new soil is slowly eroded;

[0010] (5) Make a special grounding well and bury the grounding body deeply. This method has high construction cost and is difficult to implement around the photovoltaic system. It is mostly used for substation grounding.

[0011] (6) Use electrolytic ion grounding electrodes to reduce grounding resistance, but this approach is costly.

[0012] Therefore, there is an urgent need for a method and device for reducing the resistivity of high-altitude frozen soil to solve the above problems. Summary of the invention

[0013] The object of the present invention is to provide a method and device for reducing the resistivity of frozen soil at high altitudes to solve the above-mentioned problem.

[0014] To achieve the above object, the present invention provides the following solutions:

[0015] A device for reducing the resistivity of frozen soil at high altitudes, comprising: a central conductive rod, a grounding ring is installed at the top of the central conductive rod;

[0016] The connecting ring is used to connect with the transverse galvanized flat steel;

[0017] The outer coaxial sleeve of the central conductive rod is provided with a flexible bag or a metal conductive part;

[0018] The interior of the flexible bag is communicated with the central conductive rod.

[0019] Preferably, the central conductive rod comprises a metal rod, a circular groove is formed on the top of the metal rod, a first connecting column is fixedly connected to one side of the metal rod, the length of the first connecting column matches the length of the metal rod, a liquid inlet metal rod is fixedly connected to the side of the first connecting column away from the metal rod, and the liquid outlet end at the bottom of the liquid inlet metal rod is located inside the flexible bag; the circular groove is used to install the grounding ring, and the first connecting column is detachably connected to the metal conductive part.

[0020] Preferably, the grounding ring comprises a rotating block, and the rotating block is interference-connected with the circular groove;

[0021] The top of the rotating block is coaxially rotatably connected to the bottom end of the second connecting column, the top of the second connecting column is fixedly connected to a square ring, a pressure plate is vertically slidably connected inside the square ring, the top of the pressure plate is rotatably connected to the bottom end of a screw, and the screw is threadedly connected to the top surface of the square ring.

[0022] Preferably, the metal conductive part is detachably connected to the first connecting column via a plurality of galvanized flat steel mounting rings;

[0023] The galvanized flat steel mounting ring comprises a center ring, which is coaxially sleeved on the outside of the metal rod, a limiting ring is fixedly connected to one side of the center ring, and the limiting ring is sleeved on the outside of the liquid inlet metal rod, and a first mounting portion for fixing to the first connecting column is provided at the connection between the center ring and the limiting ring;

[0024] An outer mounting ring is coaxially fixedly connected to the outer side of the central circular ring. A plurality of sliding mounting grooves are circumferentially arranged at equal intervals on the outer mounting ring. The plurality of sliding mounting grooves are used for being fixedly connected to the metal conductive part.

[0025] Preferably, the first mounting portion includes a first threaded hole, the first threaded hole is horizontally arranged at the connection between the center ring and the limiting ring, and a bolt for fixing to the first connecting column is threadedly connected in the first threaded hole.

[0026] Preferably, the metal conductive part comprises a plurality of vertical galvanized flat steels, the plurality of vertical galvanized flat steels correspond to the plurality of sliding installation grooves one by one, the vertical galvanized flat steels are slidably connected to the sliding installation grooves, and the vertical galvanized flat steels are inserted into the plurality of sliding installation grooves located in the same vertical row;

[0027] A second mounting portion for fixing to the vertical galvanized flat steel is provided in the sliding mounting groove.

[0028] Preferably, the second mounting portion includes a second threaded hole, the second threaded hole is disposed in the sliding mounting groove, and a bolt for fixing to the vertical galvanized flat steel is threadedly connected to the second threaded hole.

[0029] A method for reducing the resistivity of frozen soil at high altitudes, based on the above-mentioned device for reducing the resistivity of frozen soil at high altitudes, comprises the following steps:

[0030] Step 1: Plan the grounding point;

[0031] Step 2: Drill a hole at the planned point, and insert the central conductive rod with the flexible bag installed into the center of the drill hole;

[0032] Step 3, injecting concrete into the drilled hole, and injecting a conductive solution into the flexible bag and maintaining pressure before the concrete is finally set;

[0033] Step 4: Connect the central conductive rod to the photovoltaic system to form a ground, and allow the expanded flexible bag to squeeze the concrete until final setting;

[0034] Step 5: After the concrete is finally set, the conductive solution in the flexible bag is discharged, the central conductive rod is separated from the flexible bag, assembled with the metal conductive part, and inserted into the drill hole again;

[0035] Step 6. Fill the drill hole with low-resistance mixed soil.

[0036] Preferably, the concrete is conductive concrete.

[0037] Preferably, the drilling depth is not less than twice the thickness of the permafrost layer in the area.

[0038] Compared with the prior art, the present invention has the following advantages and technical effects:

[0039] When in use, first plan the grounding points according to the positions of each photovoltaic module, then drill holes at the planned points so that the depth of the holes is at least twice the thickness of the frozen soil layer in the area. After the drill bit is removed, insert the central conductive rod with a flexible bag installed into the center of the hole, and inject concrete on the outside of the flexible bag. At the same time, inject a conductive solution into the inside of the flexible bag and maintain pressure. The flexible bag expands to squeeze the unsolidified concrete onto the inner wall of the hole. After the concrete is finally solidified, a cylindrical hole wall is formed. During the solidification and curing of the concrete, the central conductive rod is connected to the photovoltaic module to achieve grounding of the photovoltaic module. Low resistance is achieved through the conductive solution in the flexible bag to meet the grounding requirements of the photovoltaic module. The photovoltaic modules can be put into use during the construction period. Compared with the construction of traditional photovoltaic power stations, the photovoltaic modules can be put into use in advance, saving construction time. After the concrete is finally set, the conductive solution in the flexible bag is discharged, the central conductive rod is disconnected from the photovoltaic module and pulled out from the borehole, and separated from the flexible bag. After a number of galvanized flat steel mounting rings are installed on the central conductive rod, the metal conductive part is installed through the galvanized flat steel mounting rings, and then the assembled central conductive rod, the several galvanized flat steel mounting rings and the metal conductive part are inserted into the borehole again, and the remaining gap in the borehole is filled with low-resistance mixed soil, thus completing the installation of the device.

[0040] Compared with traditional treatment methods, the present invention does not require large-scale excavation of frozen soil, nor does it require overall replacement of local frozen soil layers, which greatly reduces the construction difficulty, construction costs, and construction period. The central conductive rod and the metal conductive part are in contact with the soil layer with lower resistance in the soil, so that the overall soil resistivity in the area is reduced to meet the grounding requirements of photovoltaic modules. In the early stage of the construction of this device, by injecting a conductive solution into the flexible bag, on the one hand, it can be used as a formwork for the concrete wall in the borehole, and on the other hand, it can also be used as a grounding terminal to connect to the photovoltaic module to achieve grounding connection during the construction of the photovoltaic power station, which can effectively protect the photovoltaic module and enable the photovoltaic module to be put into use in advance. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor:

[0042] Figure 1 It is a schematic diagram of the structure of the present invention;

[0043] Figure 2 This is a schematic diagram of the ground ring structure of the present invention;

[0044] Figure 3This is a schematic diagram of the structure of the central conductive rod of the present invention;

[0045] Figure 4 This is a schematic diagram of the structure of the present invention after the flexible bag is installed;

[0046] Figure 5 This is a schematic diagram of the structure of installing a plurality of vertical galvanized flat steels according to the present invention;

[0047] Figure 6 This is a schematic diagram of the galvanized flat steel mounting ring structure of the present invention;

[0048] Figure 7 This is a schematic diagram of the structure after multiple devices of the present invention are combined in parallel;

[0049] Among them, 1. Central conductive rod; 2. Grounding ring; 3. Flexible bag; 4. Galvanized flat steel mounting ring; 5. Vertical galvanized flat steel; 6. Horizontal galvanized flat steel; 101. Metal rod; 102. Circular groove; 103. First connecting column; 104. Liquid inlet metal rod; 201. Square ring; 202. Second connecting column; 203. Screw; 204. Pressing plate; 205. Rotating block; 401. Central circular ring; 402. Limiting ring; 403. First threaded hole; 404. Second threaded hole; 405. Sliding mounting groove; 406. External mounting ring. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] Reference Figures 1 to 7 , the present invention discloses a device for reducing the resistivity of frozen soil at high altitude, comprising: a central conductive rod, a grounding ring is installed at the top of the central conductive rod;

[0053] The connecting ring is used to connect with the transverse galvanized flat steel;

[0054] The outer coaxial sleeve of the central conductive rod is provided with a flexible bag or a metal conductive part;

[0055] The interior of the flexible bag is communicated with the central conductive rod.

[0056] When in use, first plan the grounding point according to the location of each photovoltaic module, then drill a hole at the planned point, so that the drilling depth is at least twice the thickness of the frozen soil layer in the area. After the drill bit is taken out, the central conductive rod 1 equipped with the flexible bag 3 is inserted into the center of the drill hole, and concrete is injected into the outside of the flexible bag 3. At the same time, a conductive solution is injected into the inside of the flexible bag 3 and the pressure is maintained. The flexible bag 3 expands to squeeze the unsolidified concrete to the inner wall of the drill hole. After the concrete is finally solidified, a cylindrical hole wall is formed. During the solidification and curing of the concrete, the central conductive rod 1 is connected to the photovoltaic module to realize the grounding of the photovoltaic module. Through the flexible The conductive solution in the bag 3 achieves low resistance and meets the grounding requirements of the photovoltaic module. The photovoltaic module can be put into use during the construction period. Compared with the construction of traditional photovoltaic power stations, the photovoltaic module can be put into use in advance, saving construction time. After the concrete is finally set, the conductive solution in the flexible bag 3 is discharged, the central conductive rod 1 is disconnected from the photovoltaic module and pulled out of the borehole, and is separated from the flexible bag 3 and installed with the metal conductive part. Subsequently, the assembled central conductive rod 1 and the metal conductive part are inserted into the borehole again, and the remaining gap in the borehole is filled with low-resistance mixed soil, thus completing the installation of the device.

[0057] Compared with traditional treatment methods, the present invention does not require large-scale excavation of frozen soil, nor does it require overall replacement of local frozen soil layers, which greatly reduces the construction difficulty, construction costs, and construction period. The central conductive rod 1 and the metal conductive part are in contact with the soil layer with lower resistance in the soil, so that the overall soil resistivity in the area is reduced to meet the grounding requirements of the photovoltaic module. In the early stage of the construction of this device, by injecting a conductive solution into the flexible bag 3, on the one hand, it can be used as a formwork for the concrete wall in the borehole, and on the other hand, it can also be used as a grounding terminal to connect to the photovoltaic module to achieve grounding connection during the construction of the photovoltaic power station, which can effectively protect the photovoltaic module and enable the photovoltaic module to be put into use in advance.

[0058] A further optimized solution is provided, in which the central conductive rod 1 comprises a metal rod 101, a circular groove 102 is provided at the top end of the metal rod 101, a first connecting column 103 is fixedly connected to one side of the metal rod 101, the length of the first connecting column 103 matches the length of the metal rod 101, a liquid inlet metal rod 104 is fixedly connected to the side of the first connecting column 103 away from the metal rod 101, and the liquid outlet end at the bottom of the liquid inlet metal rod 104 is located inside the flexible bag 3; the circular groove 102 is used to install the grounding ring 2, and the first connecting column 103 is detachably connected to the metal conductive part.

[0059] The length of the metal rod 101 matches the depth of the borehole, and the bottom end of the metal rod 101 is used to contact the soil at the bottom of the borehole, thereby reducing the soil resistivity in this area.

[0060] The length of the first connecting column 103 matches the length of the metal rod 101 . The first connecting column 103 is used to fix the liquid inlet metal rod 104 on the one hand, and is used to fix several galvanized flat steel mounting rings 4 on the other hand.

[0061] The bottom end of the liquid inlet metal rod 104 is slightly higher than the bottom end of the metal rod 101 , and the liquid outlet end of the liquid inlet metal rod 104 is located in the flexible bag 3 .

[0062] The flexible bag 3 is made of elastic material, and the flexible bag 3 is preferably made of rubber.

[0063] The flexible bag 3 is sleeved on the outside of the metal rod 101, and the bottom liquid outlet end of the liquid inlet metal rod 104 is wrapped inside, the bottom of the flexible bag 3 and the bottom end of the metal rod 101 are fixed and sealed, and the flexible bag 3 and the metal rod 101 can be connected by wire binding and hot melting.

[0064] The top of the flexible bag 3 is fixed and sealed with the metal rod 101 in the same way, and the liquid inlet end of the liquid inlet metal rod 104 is located outside the flexible bag 3. A pressure gauge (not shown) is connected to the liquid inlet end of the liquid inlet metal rod 104, and a conductive solution is pumped into the flexible bag 3. The internal pressure of the flexible bag 3 is displayed by the pressure gauge. The flexible bag 3 expands and squeezes the unsolidified concrete, squeezing the concrete to the inner wall of the drilled hole, thereby forming a concrete protective wall.

[0065] It is recommended to use well-graded pebbles as coarse aggregate for the concrete, so that a relatively smooth inner wall can be formed after the concrete solidifies, which is convenient for the subsequent replacement of the flexible bag 3 with a metal conductive part.

[0066] In a further optimized solution, the ground ring 2 includes a rotating block 205, and the rotating block 205 is interference-connected with the circular groove 102;

[0067] The top of the rotating block 205 is coaxially rotatably connected to the bottom end of the second connecting column 202, the top of the second connecting column 202 is fixedly connected to a square ring 201, a pressure plate 204 is vertically slidably connected inside the square ring 201, the top of the pressure plate 204 is rotatably connected to the bottom end of a screw 203, and the screw 203 is threadedly connected to the top surface of the square ring 201.

[0068] The central conductive rod 1 and the grounding ring 2 are connected by interference fit between the rotating block 205 and the circular groove 102 .

[0069] The rotating block 205 is rotatably connected to the second connecting column 202 , and the square ring 201 is fixed on the top of the second connecting column 202 , so that the square ring 201 can face any direction.

[0070] When multiple holes are drilled and multiple devices are installed, multiple devices can be connected in series by inserting the transverse galvanized flat steel 6 into several square rings 201.

[0071] The transverse galvanized flat steel 6 is connected to a plurality of photovoltaic modules, thereby being able to complete the grounding of the plurality of photovoltaic modules.

[0072] The transverse galvanized flat steel 6 can be in a straight line, a right angle or a ring shape, and the square ring 201 can change its direction according to the shape of the transverse galvanized flat steel 6 .

[0073] The screw 203 is rotated to squeeze the pressing plate 204 onto the surface of the transverse galvanized flat steel 6 to fix the transverse galvanized flat steel 6, thereby realizing the series connection of each central conductive rod 1.

[0074] In a further optimized solution, the metal conductive part is detachably connected to the first connecting column 103 through a plurality of galvanized flat steel mounting rings 4;

[0075] The galvanized flat steel mounting ring 4 includes a center ring 401, which is coaxially sleeved on the outside of the metal rod 101, and a limiting ring 402 is fixedly connected to one side of the center ring 401, and the limiting ring 402 is sleeved on the outside of the liquid inlet metal rod 104. A first mounting portion for fixing to the first connecting column 103 is provided at the connection between the center ring 401 and the limiting ring 402;

[0076] An outer mounting ring 406 is coaxially fixedly connected to the outer side of the central circular ring 401 . A plurality of sliding mounting grooves 405 are circumferentially arranged at equal intervals on the outer mounting ring 406 . The plurality of sliding mounting grooves 405 are used for being fixedly connected to the metal conductive part.

[0077] The center ring 401 is coaxially sleeved on the outside of the metal rod 101, and the limiting ring 402 is sleeved on the outside of the liquid inlet metal rod 104. The center ring 401 and the limiting ring 402 are fixed. When both are sleeved, the limiting cooperation of the limiting ring 402 and the liquid inlet metal rod 104 prevents the center ring 401 from rotating relative to the metal rod 101.

[0078] An outer mounting ring 406 is coaxially fixedly connected to the outer side of the central circular ring 401 , and a sliding mounting groove 405 for mounting with a metal conductive part is reserved on the outer mounting ring 406 .

[0079] According to a further optimized solution, the first mounting portion includes a first threaded hole 403 , which is horizontally arranged at the connection between the center ring 401 and the limiting ring 402 , and the first threaded hole 403 is internally threaded with a bolt for fixing to the first connecting column 103 .

[0080] A through hole is drilled at an appropriate position on the side wall of the first connecting column 103 using a hand drill. When the center ring 401 and the limit ring 402 slide to the specified position along the length direction of the first connecting column 103, the bolt is passed through the first threaded hole 403 and the corresponding through hole, and the bolt is threadedly connected with the nut to complete the fixation of the center ring 401 and the center conductive rod 1.

[0081] The first connecting column 103 and the center ring 401 may also be relatively fixed by inserting a pin or a wire into the through hole.

[0082] Further optimized solution, the metal conductive part includes a plurality of vertical galvanized flat steels 5, the plurality of vertical galvanized flat steels 5 correspond to a plurality of sliding installation grooves 405 one by one, the vertical galvanized flat steels 5 are slidably connected to the sliding installation grooves 405, and the vertical galvanized flat steels 5 are inserted into a plurality of sliding installation grooves 405 located in the same vertical row;

[0083] A second mounting portion for fixing to the vertical galvanized flat steel 5 is provided in the sliding mounting groove 405 .

[0084] The metal conductive part includes a plurality of vertical galvanized flat steels 5, which are arranged at equal intervals around the metal rod 101. The vertical galvanized flat steels 5 are mainly used for conduction to reduce the resistivity of high-resistance soil. The arrangement of multiple vertical galvanized flat steels 5 increases the conductive cross-sectional area, which is beneficial to the reduction of resistivity. At the same time, it can be used as a metal support for the concrete retaining wall to prevent the concrete retaining wall from collapsing.

[0085] The vertical galvanized flat steel 5 is passed through the sliding installation groove 405 on each galvanized flat steel mounting ring 4 in turn. The sliding installation groove 405 is provided with a stepped structure. The cross section of the vertical galvanized flat steel 5 matches the cross section of the sliding installation groove 405. Then, the vertical galvanized flat steel 5 is fixed to each sliding installation groove 405 through the second mounting part to complete the installation of the vertical galvanized flat steel 5.

[0086] According to a further optimized solution, the second mounting portion includes a second threaded hole 404 , which is provided in the sliding mounting groove 405 , and the second threaded hole 404 is threadedly connected with a bolt for fixing with the vertical galvanized flat steel 5 .

[0087] When in use, after the vertical galvanized flat steel 5 is inserted into each sliding mounting groove 405, a through hole is drilled on the vertical galvanized flat steel 5 by a hand drill, and the through hole is aligned with the corresponding second threaded hole 404, and then the bolt is passed through the second threaded hole 404 and the through hole and tightened, thereby completing the fixation of the vertical galvanized flat steel 5 and the outer mounting ring 406.

[0088] A method for reducing the resistivity of frozen soil at high altitudes, based on the above-mentioned device for reducing the resistivity of frozen soil at high altitudes, comprises the following steps:

[0089] Step 1: Plan the grounding point;

[0090] According to the location of each photovoltaic module in the photovoltaic power station, a suitable location is selected to set the grounding point. The location of the grounding point can evenly connect each installed photovoltaic module, thereby avoiding the waste of connecting wires.

[0091] Step 2: Drill a hole at the planned point, and insert the central conductive rod 1 with the flexible bag 3 installed into the center of the drilled hole;

[0092] After determining the location, drill holes in the frozen soil layer at the planned location. When drilling, ensure that the holes are drilled vertically downward to ensure that the drilling depth meets the requirements.

[0093] After the drilling is completed, the central conductive rod 1 with the flexible bag 3 installed is inserted into the center of the drilled hole, and the central conductive rod 1 is ensured to be in a vertical state.

[0094] Step 3: inject concrete into the drilled hole, and before the concrete is finally set, inject a conductive solution into the flexible bag 3 and maintain the pressure;

[0095] A certain amount of conductive solution is injected into the flexible bag 3 in advance to expand the flexible bag 3, and then concrete is injected into the outside of the flexible bag 3. When the concrete fills the drill hole, the conductive solution is continuously injected into the flexible bag 3, and a certain pressure is maintained in the flexible bag 3. The expanded flexible bag 3 squeezes the concrete into a cylindrical shape, and the excess concrete penetrates into the soil side wall, thereby improving the bonding strength between the concrete retaining wall and the drill hole.

[0096] When the injection pressure of the conductive solution exceeds the specified pressure, the injection of the conductive solution is stopped, and the liquid inlet of the liquid inlet metal rod 104 is closed.

[0097] Step 4: Connect the central conductive rod 1 to the photovoltaic system to form a ground, and allow the expanded flexible bag 3 to squeeze the concrete until it is finally set;

[0098] After the conductive solution is injected, the expanded flexible bag 3 squeezes the concrete with a certain pressure and maintains the shape of the concrete retaining wall until the concrete is finally set.

[0099] After the concrete has finally set, continue to cure the concrete according to standards until it develops strength.

[0100] Usually, the concrete curing period is long, which will delay the use of photovoltaic modules. At this time, by connecting the grounding end of the photovoltaic module to the central conductive rod 1, the conductive solution in the flexible bag 3 acts as a medium to reduce the soil resistivity in the area. During the concrete curing period, if a lightning strike occurs, a strong current can be introduced into the conductive solution of the flexible bag 3 and then enter the soil at the depth of the soil layer, thereby protecting the photovoltaic module.

[0101] The photovoltaic modules can be put into use before the device is fully built, thus shortening the construction period of the photovoltaic power station.

[0102] During the concrete curing period, by observing the indication of the pressure gauge connected to the liquid inlet metal rod 104, if the pressure gauge shows that the pressure in the flexible bag 3 decreases, the conductive solution is continuously added to the flexible bag 3 until the pressure requirement is met.

[0103] Step 5: After the concrete is finally set, the conductive solution in the flexible bag 3 is discharged, the central conductive rod 1 is separated from the flexible bag 3, assembled with the metal conductive part, and inserted into the drill hole again;

[0104] After the concrete solidifies and develops strength, the conductive solution in the flexible bag 3 is discharged through a water pump, and the flexible bag 3 shrinks. At this time, the central conductive rod 1 and the flexible bag 3 can be pulled out at the same time.

[0105] It should be noted that the connection between the central conductive rod 1 and the photovoltaic module must be disconnected before the central conductive rod 1 and the flexible bag 3 are pulled out. After the central conductive rod 1 is replaced, the connection between the next central conductive rod 1 and the photovoltaic module is disconnected, so that the central conductive rod 1 can be replaced while grounding protection is provided, without delaying the operation of the photovoltaic power station.

[0106] After removing the flexible bag 3, several galvanized flat steel mounting rings 4 are sequentially mounted on the metal rod 101, and the several galvanized flat steel mounting rings 4 are fixed to the metal rod 101 through the first connecting column 103. Then, the vertical galvanized flat steel 5 is sequentially passed through the sliding mounting groove 405 on each galvanized flat steel mounting ring 4, and the vertical galvanized flat steel 5 is fixed to each sliding mounting groove 405.

[0107] After the installation of the plurality of vertical galvanized flat steels 5 is completed, the central conductive rod 1 and the plurality of vertical galvanized flat steels 5 are hoisted and inserted into the inner side of the concrete retaining wall.

[0108] Step 6. Fill the drill hole with low-resistance mixed soil.

[0109] After the central conductive rod 1 and the plurality of vertical galvanized flat steels 5 are inserted, there is still a gap between the central conductive rod 1 and the plurality of vertical galvanized flat steels 5 , and the soil mixed with the resistance reducing agent is filled into the gap between the central conductive rod 1 and the plurality of vertical galvanized flat steels 5 .

[0110] By using such a filling method, the overall replacement of the area is avoided, thereby greatly reducing the construction difficulty and cost. At the same time, due to the arrangement of the central conductive rod 1 and the plurality of vertical galvanized flat steels 5, even in a low temperature environment, the resistivity of the filled low-resistance mixed soil gradually increases, and the central conductive rod 1 and the plurality of vertical galvanized flat steels 5 can be used to reduce the overall resistivity, ensuring that the resistance meets the grounding requirements of the photovoltaic module.

[0111] The solution is further optimized so that the concrete is conductive concrete.

[0112] When the concrete is conductive concrete, the conductive concrete can enter the soil gaps on the side walls of the borehole due to the squeezing of the flexible bag 3, thereby increasing the contact area between the conductive concrete and the soil, making it easier for the current to be transmitted to the soil on both sides of the borehole. At the same time, the conductive concrete increases the effective conductive cross-sectional area of ​​the borehole, making it easier for the current to be quickly transmitted to deep soil layers.

[0113] After conductive concrete is cured, it has low internal moisture content, is dense, is not easily affected by freezing weather, and can maintain a low resistance state for a long time.

[0114] To further optimize the plan, the drilling depth should be no less than twice the thickness of the permafrost layer in the area.

[0115] To ensure the effectiveness of the implementation, the drilling depth should be as deep as possible to pass through the permafrost layer and reach the constant temperature layer. The soil resistivity in the constant temperature layer is low, which is convenient for transmitting large amounts of current.

[0116] In addition, depending on the location of the project, some areas are permafrost areas. Affected by the local climate, the depth of the permafrost will gradually increase. In order to ensure the long-term use of the photovoltaic power station, setting the drilling depth to twice the thickness of the local permafrost layer is a reasonable choice that takes into account both economic benefits and service life.

[0117] The thickness of the frozen soil layer in seasonal frozen soil areas can be referred to the national standard "Code for Design of Building Foundations". The thickness of the frozen soil layer in permanently frozen soil areas needs to be determined based on actual survey conditions.

[0118] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0119] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A device for reducing the resistivity of frozen soil at high altitudes, characterized in that: include: A central conductive rod, a grounding ring is installed on the top of the central conductive rod; The connecting ring is used to connect with the transverse galvanized flat steel; The outer coaxial sleeve of the central conductive rod is provided with a flexible bag or a metal conductive part; The interior of the flexible bag is in communication with the central conductive rod; The central conductive rod comprises a metal rod, a circular groove is formed at the top of the metal rod, a first connecting column is fixedly connected to one side of the metal rod, the length of the first connecting column matches the length of the metal rod, a liquid inlet metal rod is fixedly connected to the side of the first connecting column away from the metal rod, and the liquid outlet end at the bottom of the liquid inlet metal rod is located inside the flexible bag; the circular groove is used to install the grounding ring, and the first connecting column is detachably connected to the metal conductive part; The metal conductive part is detachably connected to the first connecting column via a plurality of galvanized flat steel mounting rings; The galvanized flat steel mounting ring comprises a center ring, which is coaxially sleeved on the outside of the metal rod, a limiting ring is fixedly connected to one side of the center ring, and the limiting ring is sleeved on the outside of the liquid inlet metal rod, and a first mounting portion for fixing to the first connecting column is provided at the connection between the center ring and the limiting ring; An outer mounting ring is coaxially fixedly connected to the outer side of the central circular ring. A plurality of sliding mounting grooves are circumferentially arranged at equal intervals on the outer mounting ring. The plurality of sliding mounting grooves are used for being fixedly connected to the metal conductive part.

2. The device for reducing the resistivity of frozen soil at high altitudes according to claim 1, characterized in that: The grounding ring comprises a rotating block, and the rotating block is interference-connected with the circular groove; The top of the rotating block is coaxially rotatably connected to the bottom end of the second connecting column, the top of the second connecting column is fixedly connected to a square ring, a pressure plate is vertically slidably connected inside the square ring, the top of the pressure plate is rotatably connected to the bottom end of a screw, and the screw is threadedly connected to the top surface of the square ring.

3. The device for reducing the resistivity of frozen soil at high altitudes according to claim 1, characterized in that: The first mounting portion includes a first threaded hole, which is horizontally arranged at the connection between the center ring and the limiting ring. A bolt for fixing with the first connecting column is threadedly connected in the first threaded hole.

4. The device for reducing the resistivity of high-altitude frozen soil according to claim 1, characterized in that: The metal conductive part includes a plurality of vertical galvanized flat steels, the plurality of vertical galvanized flat steels correspond to the plurality of sliding installation grooves one by one, the vertical galvanized flat steels are slidably connected to the sliding installation grooves, and the vertical galvanized flat steels are inserted into the plurality of sliding installation grooves located in the same vertical row; A second mounting portion for fixing to the vertical galvanized flat steel is provided in the sliding mounting groove.

5. The device for reducing the resistivity of frozen soil at high altitudes according to claim 4, characterized in that: The second mounting portion includes a second threaded hole, which is disposed in the sliding mounting groove, and a bolt for fixing to the vertical galvanized flat steel is threadedly connected in the second threaded hole.

6. A method for reducing the resistivity of frozen soil at high altitudes, based on the device for reducing the resistivity of frozen soil at high altitudes according to any one of claims 1 to 5, characterized in that: The steps include: Step 1: Plan the grounding point; Step 2: Drill a hole at the planned point, and insert the central conductive rod with the flexible bag installed into the center of the drill hole; Step 3, injecting concrete into the drilled hole, and injecting a conductive solution into the flexible bag and maintaining pressure before the concrete is finally set; Step 4: Connect the central conductive rod to the photovoltaic system to form a ground, and allow the expanded flexible bag to squeeze the concrete until final setting; Step 5: After the concrete is finally set, the conductive solution in the flexible bag is discharged, the central conductive rod is separated from the flexible bag, assembled with the metal conductive part, and inserted into the drill hole again; Step 6. Fill the drilled hole with low-resistance mixed soil.

7. A method for reducing the resistivity of high-altitude frozen soil according to claim 6, characterized in that: The concrete is conductive concrete.

8. A method for reducing the resistivity of high-altitude frozen soil according to claim 6, characterized in that: The drilling depth shall not be less than twice the thickness of the permafrost layer in the area.

Images