32results about How to "Reduce step voltage" patented technology

The invention discloses a grounding method of reducing local impact grounding resistance of a power plant and a substation, which comprises an inner-layer annular horizontal grounding body, an outer-layer annular horizontal grounding body, a horizontal connection body and a vertical grounding body. According to the grounding method of reducing local impact grounding resistance of a power plant and a substation, local impact grounding resistance of a power plant and a substation can be reduced, diffusion of local impact grounding current is enhanced, a grounding grid local electric potential can be prevented from rising, and safety of primary and secondary devices such as a transformer can be protected; electric potential and electric field distribution around a grounding electrode can be improved, the step voltage, device contact voltage values and the like can be reduced; and the grounding method of reducing local impact grounding resistance of a power plant and a substation has the advantages of wide application range, convenient construction, corrosion resistance, safety and reliability, and long service life.

A grounding module comprises a module body and is characterized in that the formula of the grounding module basically comprises the following components in parts by weight: 13-17 parts of coke powder, 1.5-8 parts of cement, and 0.3-5 parts of graphite powder. The formula of the grounding module further comprises 0.3-5 parts of ion releasing agent. The grounding module has the advantages that the grounding module adopts natural nonmetallic mineral materials which have excellent conductivity and soil compatibility as conducting medium of the grounding module, conductivity of the grounding module is not affected by seasons, so that stable ground resistance is provided, besides, due to the nonmetallic mineral materials, a low resistance zone which is gentle in variation is formed between metal and soil which have huge difference in resistivity, step voltage and contact voltage are lowered, probability of occurrence of ground potential counterattack is reduced, moreover, by matching an ion releaser, electrolyte can durably permeate into the soil in a high concentration mode, the goal that ground resistance can be rapidly lowered is achieved, and characteristics of the grounding module such as density, corrosion resistance, conductivity, compressive strength are enhanced.

The invention relates to a substation grounding grid in frozen earth area and a design method thereof and belongs to the technical field of substation construction. The grounding grid is a mesh structure in which a plurality of horizontal trunk lines and longitudinal trunk lines are connected, and the grounding grid includes a horizontal grounding grid and a sinking grounding grid where the edge of the horizontal grounding grid is bent downwards. The horizontal grounding grid is located in a frozen earth layer. The lowermost end of the sinking grounding grid is located below the frozen earth layer; and the intersections of the horizontal trunk lines and the longitudinal trunk lines are connected with grounding resistors in the downward directions, and the lowermost ends of the grounding resistors extend below the frozen earth layer. The invention optimizes the structure of the grounding grid, and reduces the stepping voltage and the contact potential of the grounding grid, thereby meeting the safety performance requirements of the grounding grid in areas with high soil resistivity and deep seasonal frozen earth. The invention does not need to increase the amount of material of thegrounding grid, does not need to expand the land acquisition area of the grounding grid and does not use additional chemical resistance-reducing substances, and reduces the investment of the project.

The invention discloses a construction process of an argilloid geological ground network. The construction process comprises the following steps of 1, material preparation and site preparation; 2, measurement, positioning and groove digging; 3, vertical grounding body laying; 4, horizontal grounding body laying; 5, grounding system welding; 6, groove filling; 7, waterproof processing during a grounding leading-up line penetrating through a cushion layer; and 8, grounding resistance measurement, in which the 50-by-6 galvanized flat steel horizontal grounding body with length larger than or equal to 6 meters, the 50-by-50-by-5 vertical grounding body in 2,500 millimeters, a 50-by-6 horizontal pressure-sharing belt, a 50-by-6 galvanized flat steel grounding leading-out line and resistance reduction agent are prepared, a corresponding construction operating surface is ensured, the leveling of a base is completed, and check and acceptance are performed according to bearing capability of foundation pit. By the process, the resistance is favorable reduced, the corrosion-resistant capability is improved, the step voltage can be reduced, the personal safety is improved, water prevention isfacilitated, the excavation area of a plant is favorably reduced, and the construction cost is reduced.

The present invention discloses a novel step voltage calculation method based on circular ring-shaped DC power transmission earth electrode different buried depths. The method comprises the followingtwo situations of (1) analyzing the potential distribution that the homogeneous medium circular ring-shaped earth electrodes are not buried at the equal depth to obtain a calculation expression of a step voltage on an earth surface; (2) analyzing the potential distribution that the horizontal dual-layer medium circular ring-shaped earth electrodes are not buried at the equal depth to obtain a calculation expression of the step voltage on the earth surface; utilizing a MALTAB software to simulate to obtain the results and the influence of different earth electrode ring numbers and different buried depths on a surface potential, thereby demonstrating that the method provided by the present invention enables the step voltage to be reduced. The present invention creatively provides the thoughtthat the dual-circular ring-shaped earth electrodes are not buried at the equal depth, the calculation is simple, and the operation speed is fast.

The invention provides a grounding device of a transformer substation containing inlet and outlet cables. The grounding device comprises cable trench support flat steel, indoor leading flat steel, an indoor grounding main line and overlap region tin coatings, wherein the cable trench support flat steel penetrates through a cable trench support stand column, the indoor leading flat steel is in locked connection with the cable trench support flat steel through a first screw, the indoor grounding main line is in locked connection with the indoor leading flat steel through a first screw, and the overlap region tin coatings are arranged between the cable trench support flat steel and the indoor leading flat steel and between the indoor leading flat steel and the indoor grounding main line. The invention discloses the grounding device of the transformer substation containing inlet and outlet cables and a mounting method of the grounding device. According to the invention, since flat steel or a copper stranded wire is used for connecting the grounding device in a cable structure with a transformer substation grounding network, the grounding device in the cable structure can be used for shunting the transformer substation grounding network, thereby reducing the total ground resistance, further reducing the earth current of the transformer substation grounding network and lowering the contact voltage and step voltage of the transformer substation.

The invention discloses a lightweight graphite resistance reduction module and a preparation method thereof. The lightweight graphite resistance reduction module is prepared form expanded graphite, glass fiber mesh cloth, graphite resistance reduction cloth and graphite woven belt material. The lightweight graphite resistance reduction module can be made into a block shape, a plate shape or a cylindrical shape and is high in plasticity and structural strength. The preparation method includes the processes of laying, fixing, pressing, coating and re-pressing. The lightweight graphite resistancereduction module has the advantages of being small in density, light in weight, high in strength, good in water absorption, excellent in electrical conductivity and the like.

The invention discloses a construction method for a mud rock geological grounding grid. The method comprises the following steps that 1, materials are prepared, and field preparation is conducted; 2,measurement and positioning are conducted, and grooves are dug; 3, vertical grounding bodies are laid; 4, horizontal grounding bodies are laid; 5, a grounding system is welded; 6, the grooves are backfilled; 7, a grounding outgoing line is prepared; 8, the grounding outgoing line is connected with a grounding busbar; 9, the grounding resistance is measured. The 50*6 galvanized flat steel horizontal grounding bodies with the lengths larger than or equal to 6 m, the 50*50*5 vertical grounding bodies with the lengths of 2,500 mm, 100 mm*100 mm*10 mm Q235 galvanized steel plates and the 50 mm*5 mmT2 purple flat steel grounding outgoing line are prepared and subjected to foundation pit bearing capacity inspection and acceptance. The method helps to well lower the resistance and improve the anti-corrosion capacity, the step voltage can be lowered, the personal safety coefficient is increased, the good water penetration prevention capacity is achieved at the same time, and the method is beneficial to rust prevention.

The invention provides a grounding electrode insulation shielding structure used for reducing the pace voltage of grounding electrodes, which comprises the grounding electrode that is arranged under the ground surface, a coke bed covering the grounding electrode, and an insulating barrier that is arranged between the grounding electrode and the ground surface and is used for preventing the electric current from flowing towards superficial layer soil and forcing the electric current from flowing towards submerged soil, thus reducing the pace voltage of the ground surface. According to the structure, the maximum pace voltage is reduced in a way of saving more instruction funds under the condition that the size of the grounding electrode is not increased, and land occupying area is not enlarged.

The invention relates to an intelligent arc extinction and resonance extinction overvoltage protection integral optimization device and belongs to the technical field of electric network protection equipment. The integral optimization device is characterized by comprising a cabinet body, wherein an isolation switch, a PT (platinum) resonance extinction device, a high-capacity integral overvoltage protector, a single-phase vacuum contactor and a high-voltage current limiting fuse are arranged in the cabinet body, an intelligent controller is arranged on a surface door of the cabinet body, the isolation switch is respectively connected with the PT resonance extinction device, the high-capacity integral overvoltage protector and the high-voltage current limiting fuse, the high-voltage current limiting fuse is connected with the single-phase vacuum contactor, and the intelligent controller is respectively connected with the PT resonance extinction device and the single-phase vacuum contactor. The intelligent arc extinction and resonance extinction overvoltage protection integral optimization device has the advantages that the overvoltage ascending front edge can be effectively gentled, the voltage peak is smoothed, the ultra-low frequency oscillation current is inhibited, the frequent fuse phenomenon of the fuse is eliminated, and the arc grounding voltage is effectively limited.

A microcomputer arc-extinguishing, harmonic-eliminating and overvoltage-protecting device relates to the technical field of arc extinguishing and harmonic eliminating of an electric power system. The microcomputer arc-extinguishing, harmonic-eliminating and overvoltage-protecting device comprises a high-voltage current-limiting fuse, a voltage transformer, a three-phase combined type overvoltage protector, a vacuum contactor, a microcomputer arc-extinguishing controller, a high-voltage fuse and a zero-sequence current transformer, wherein three-phase ports of the three-phase combined type overvoltage protector are connected with a three-phase high-voltage isolation switch; a grounding terminal of the three-phase combined type overvoltage protector is connected with the voltage transformer and then grounded; the high-voltage fuse is connected in series between three-phase ports of the voltage transformer and the three-phase high-voltage isolation switch; a voltage transformer control terminal of the microcomputer arc-extinguishing controller is connected with the voltage transformer; a vacuum contactor control terminal of the microcomputer arc-extinguishing controller is connected with the vacuum contactor; three-phase ports of the high-voltage current-limiting fuse are respectively connected with the three-phase high-voltage isolation switch, while the other ends of the high-voltage current-limiting fuse are connected with the vacuum contactor; a grounding terminal of the vacuum contactor is grounded; and the zero-sequence current transformer is arranged between the grounding terminal of the vacuum contactor and a grounding point. The overvoltage-protecting device is high in action speed and capable of arc-extinguishing and harmonic-eliminating.

A microcomputer arc-extinguishing, harmonic-eliminating and overvoltage-protecting device relates to the technical field of arc extinguishing and harmonic eliminating of an electric power system. The microcomputer arc-extinguishing, harmonic-eliminating and overvoltage-protecting device comprises a high-voltage current-limiting fuse, a voltage transformer, a three-phase combined type overvoltage protector, a vacuum contactor, a microcomputer arc-extinguishing controller, a high-voltage fuse, and a zero-sequence current transformer, wherein three-phase ports of the three-phase combined type overvoltage protector are respectively connected with a three-phase high-voltage isolation switch; a grounding terminal of the three-phase combined type overvoltage protector is connected with the voltage transformer and then grounded; the high-voltage fuse is connected in series between three-phase ports of the voltage transformer and the three-phase high-voltage isolation switch; a voltage transformer control terminal of the microcomputer arc-extinguishing controller is connected with the voltage transformer; a vacuum contactor control terminal of the microcomputer arc-extinguishing controller is connected with the vacuum contactor; three-phase ports of the high-voltage current-limiting fuse are respectively connected with the three-phase high-voltage isolation switch, while the other ends of the high-voltage current-limiting fuse are connected with the vacuum contactor; a grounding terminal of the vacuum contactor is grounded; and the zero-sequence current transformer is arranged between the grounding terminal of the vacuum contactor and a grounding point. The overvoltage-protecting device is high in action speed and capable of arc-extinguishing and harmonic-eliminating.

The invention provides a microcomputer arc-extinguishing resonance-elimination overvoltage protection device and relates to the technical field of electric power system arc-extinguishing and resonance-elimination. The microcomputer arc-extinguishing resonance-elimination overvoltage protection device comprises a high-voltage current limiting fuse, a voltage transformer, a three-phase combined overvoltage protector, a vacuum contactor, a microcomputer arc-extinguishing controller, a high-voltage fuse and a zero-sequence current transformer. Three phase ports of the three-phase combined overvoltage protector are respectively connected with a three-phase high-voltage isolation switch. A grounded end is connected with the voltage transformer and then is grounded. The high-voltage fuse is serially connected between three phase ports of the voltage transformer and the three-phase high-voltage isolation switch. A voltage transformer control end of the microcomputer arc-extinguishing controller is connected with the voltage transformer, and a vacuum contactor control end is connected with the vacuum contactor. Three phase ports of the high-voltage current limiting fuse are respectively connected with the three-phase high-voltage isolation switch, and the other end of the high-voltage current limiting fuse is connected with the vacuum contactor. A grounded end of the vacuum contactor is grounded, and a zero-sequence current transformer is arranged between the grounded end and a grounding point. The overvoltage protection device provided by the invention is high is action speed and is capable of realizing arc-extinguishing and resonance-elimination.

The invention provides an arc and resonance elimination and overvoltage protection device of a microcomputer, and relates to the technical field of arc and resonance elimination of power systems. The arc and resonance elimination and overvoltage protection device comprises high-voltage current-limiting fuses, a voltage transformer, a three-phase combined overvoltage protector, vacuum contactors, a microcomputer arc elimination controller, high-voltage fuses and a zero-sequence current transformer, wherein three phases of ports of the three-phase combined overvoltage protector are connected with three phases of high-voltage isolating switches respectively and a ground terminal is connected with the voltage transformer and then grounded; the high-voltage fuses are connected between three phases of ports of the voltage transformer and the three phases of high-voltage isolating switches in series; a voltage transformer control terminal of the microcomputer arc elimination controller is connected with the voltage transformer and a vacuum contactor control terminal is connected with the vacuum contactors; three phases of ports of the high-voltage current-limiting fuses are connected with the three phases of high-voltage isolating switches respectively and the other ends are connected with the vacuum contactors; a vacuum contactor ground terminal is grounded; and the zero-sequence current transformer is arranged between the ground terminal and a ground point. The arc and resonance elimination and overvoltage protection device of the microcomputer is high in acting speed and is an overvoltage protection device capable of achieving arc and resonance elimination.

The present invention discloses a novel step voltage calculation method based on circular ring-shaped DC power transmission earth electrode different buried depths. The method comprises the followingtwo situations of (1) analyzing the potential distribution that the homogeneous medium circular ring-shaped earth electrodes are not buried at the equal depth to obtain a calculation expression of a step voltage on an earth surface; (2) analyzing the potential distribution that the horizontal dual-layer medium circular ring-shaped earth electrodes are not buried at the equal depth to obtain a calculation expression of the step voltage on the earth surface; utilizing a MALTAB software to simulate to obtain the results and the influence of different earth electrode ring numbers and different buried depths on a surface potential, thereby demonstrating that the method provided by the present invention enables the step voltage to be reduced. The present invention creatively provides the thoughtthat the dual-circular ring-shaped earth electrodes are not buried at the equal depth, the calculation is simple, and the operation speed is fast.

A high-conductivity exothermic solder powder suitable for use in acidic soil, the solder powder includes the following components in parts by weight: copper oxide: 15-20 parts, aluminum powder: 20-25 parts, copper powder: 35 parts -50 parts, alloy powder: 5-15 parts, molybdenum: 3-8 parts, oxygen scavenger: 1-2 parts, slagging agent 1-2 parts, rare earth 1-2 parts, the weight of chromium in the alloy powder The percentage is 25-35%, the weight percentage of manganese is 20-25%, the weight percentage of manganese nitride is 15-25%, and the balance is aluminum. The exothermic solder powder involved in the present invention will not crystallize in acidic soil. Inter-corrosion, good conductivity.

The invention provides a simple and easy grounding grid overhauling device. The simple and easy grounding grid overhauling device comprises an overhauling grounding mechanism and a maintenance electric welding machine capable of maintaining faults, wherein the overhauling grounding mechanism comprises a grounding rod A with a grounding function, a grounding rod B with the grounding function and an insulating clamp with an insulating function; the grounding rod A and the grounding rod B are provided with iron pieces. Aiming at the problem of existing technical equipment that a grounding line is released from a grounding body or a grounding grid to generate electricity leakage; the overhauling grounding mechanism and the maintenance electric welding machine capable of maintaining the faults are adopted, so that the contact voltage and the step voltage can be obviously reduced; a lot of fault power supplies flow into the ground from the grounding grid to a vertical electrode so as to correspondingly reduce the scattered flow of a horizontal conductor.

The invention relates to a microcomputer arc harmonic elimination and overvoltage protection device and belongs to the arc harmonic elimination field of an electrical power system. The protection device comprises a high voltage current limit fuse, a voltage transformer, a three-phase combined overvoltage protection device, a vacuum contactor, a microcomputer arc elimination controller, a high voltage fuse and a zero sequence current transformer, wherein three-phase ports of the three-phase combined overvoltage protection device are respectively connected with a three-phase high voltage isolation switch, a ground end is connected with the voltage transformer and is then in ground connection, the high voltage fuse is connected between three-phase ports of the voltage transformer and the three-phase high voltage isolation switch, a voltage transformer control end of the microcomputer arc elimination controller is connected with the voltage transformer, a vacuum contactor control end is connected with the vacuum contactor, three-phase ports of the high voltage current limit fuse are respectively connected with the three-phase high voltage isolation switch, the other end is connected with the vacuum contactor, a ground end of the vacuum contact is in ground connection, and the zero sequence current transformer is arranged between the ground end and a ground point. The protection device is advantaged in that the motion speed is fast, and arc harmonic elimination effects can be realized.

The invention provides a grounding electrode insulation shielding structure used for reducing the pace voltage of grounding electrodes, which comprises the grounding electrode that is arranged under the ground surface, a coke bed covering the grounding electrode, and an insulating barrier that is arranged between the grounding electrode and the ground surface and is used for preventing the electric current from flowing towards superficial layer soil and forcing the electric current from flowing towards submerged soil, thus reducing the pace voltage of the ground surface. According to the structure, the maximum pace voltage is reduced in a way of saving more instruction funds under the condition that the size of the grounding electrode is not increased, and land occupying area is not enlarged.

The invention relates to the field of a lightning-protection grounding geographic pole and particularly relates to a graphite lightning-protection grounding module and a preparation method thereof. The graphite lightning-protection grounding module is made from graphite powder, granular graphite and asphalt. The preparation method comprises the steps of material preparing, kneading, blank preparing, roasting, post processing, and the like. The graphite lightning-protection grounding module disclosed by the invention is low in electrical resistivity, relatively high in mechanical strength, resistant to corrosion and long in service life.

The invention discloses a lightning-protection manual grounding system and a construction method by utilizing a structure steel bar externally-connected downlead wire. The system comprises a structure steel bar downlead wire (2) fixed into a building structure outer wall column (1) and connected with a lightning arrester on the top of a building. The lightning-protection manual grounding system is characterized in that the downlead wire of the lightning-protection manual grounding system is formed by the structure steel bar downlead wires (2) and a non-structural steel bar downlead wire (5). The structure steel bar downlead wires (2) are connected to form a group through jumper wires. The portions, under the ground, of the structure steel bar downlead wires (2) are transversely and fixedly provided with a connection plate (4); and the connection plate (4) is externally connected to the non-structural steel bar downlead wire (5) which is connected with a manual grounding body (6). The lightning-protection manual grounding system is suitable for the practice that in a reinforced concrete structure, structure steel bars and non-structural steel bars jointly serve as the downlead wires, and the manual grounding body or a composite lightning protection grounding device are used, and limitation of independent foundation, strip foundation, pile foundation and slab foundation and the like is not the case.

The invention discloses an arc extinction, harmonic elimination and overvoltage protection device of a microcomputer, and relates to the technical field of arc extinction and harmonic elimination of a power system. The arc extinction, harmonic elimination and overvoltage protection device comprises high-voltage current-limiting fuses, a voltage transformer, a three-phase combined overvoltage protector, vacuum contactors, a microcomputer arc extinction controller, high-voltage fuses and a zero sequence current transformer, wherein three phase ports of the three-phase combined overvoltage protector are separately connected with three phase high-voltage isolation switches, a ground end is connected with the voltage transformer and then is grounded, the high-voltage fuses are connected in series between three phase ports of the voltage transformer and the three phase high-voltage isolation switches, a voltage transformer control end of the microcomputer arc extinction controller is connected with the voltage transformer, vacuum contactor control ends are connected with the vacuum contactors, the three phase ports of the high-voltage current-limiting fuses are separately connected with the three phase high-voltage isolation switches, the other ends of the high-voltage current-limiting fuses are connected with the vacuum contactors, vacuum contactor ground ends are grounded, and the zero sequence current transformer is arranged between the ground end and a ground point. The overvoltage protection device has the advantages of fast action speed and can be used for arc extinction and harmonic elimination.

Electric resistance stone materials and a method for manufacturing the same are provided to reduce a step voltage and a contact voltage and to maintain high electric resistance for a long period of time by securing water repellent characteristic and non-repairing characteristic based on a silicon water repellent layer. A method for manufacturing electric resistance stone materials(1) includes the following: A composition containing (A) components and (B) components is prepared. The composition is attached to the surface of dry natural stone(2) of 5-50mm diameters. A heat treating process is implemented at a temperature between 50 and 250 degrees Celsius. The (A) components are organopolysiloxane containing at least three Si-H bonds in one molecule, and the (B) components are platinum catalysts.

The invention relates to a device for reducing step voltage of a neutral point grounding electrode. The device is characterized in that an insulation grounding conducting wire rod is arranged between a grounding electrode buried underground and a transformer neutral point joint; the insulation grounding conducting wire rod consists of a middle electrical conductor and an insulation external layersurrounding the middle electrical conductor; the end C of the middle electrical conductor of the insulation grounding conducting wire rod is connected with the grounding electrode buried underground,and the end S of the middle electrical conductor of the insulation grounding conducting wire rod is connected with the transformer neutral point joint; and the vertically-buried underground depth of the insulation grounding conducting wire rod is more than or equal to the spanning distance of 0.8m. The device for reducing the step voltage of the neutral point grounding electrode, provided by the invention, has the advantages of being capable of being applied to the grounding systems of various lightning arresters in an extending manner, reducing the step voltage around the grounding wires when the lightning arresters work, and decreasing the harm to people or livestock, caused by the most dangerous areas of the step voltage, to the minimum.

The invention discloses a substation independent lightning rod grounding device and an optimization method, belongs to the technical field of electric power engineering grounding, and particularly relates to a substation independent lightning rod grounding device and an optimization method thereof. The basic form and the optimization form of the independent lightning rod are determined, safety verification is carried out on the distance between the grounding device and the main grounding grid, the connection mode of the independent lightning rod grounding device and the main grounding grid andthe distance requirement of the lightning rod and 35kV and below equipment are determined, and a basis is provided for design and construction of the independent lightning rod. And the probability ofcounterattack discharge to a protected object when the lightning rod is struck by lightning is prevented or reduced.

The invention discloses an arc extinction, harmonic elimination and overvoltage protection device of a microcomputer, and relates to the technical field of arc extinction and harmonic elimination of a power system. The arc extinction, harmonic elimination and overvoltage protection device comprises high-voltage current-limiting fuses, a voltage transformer, a three-phase combined overvoltage protector, vacuum contactors, a microcomputer arc extinction controller, high-voltage fuses and a zero sequence current transformer, wherein three phase ports of the three-phase combined overvoltage protector are separately connected with three phase high-voltage isolation switches, a ground end is connected with the voltage transformer and then is grounded, the high-voltage fuses are connected in series between the three phase ports of the voltage transformer and the three phase high-voltage isolation switches, a voltage transformer control end of the microcomputer arc extinction controller is connected with the voltage transformer, vacuum contactor control ends are connected with the vacuum contactors, the three phase ports of the high-voltage current-limiting fuses are separately connected with the three phase high-voltage isolation switches, the other ends of the high-voltage current-limiting fuses are connected with the vacuum contactors, vacuum contactor ground ends are grounded, and the zero sequence current transformer is arranged between the ground end and a ground point. The overvoltage protection device has the advantages of fast action speed and can be used for arc extinction and harmonic elimination.

The invention relates to a method for laying a direct current grounding pole, which belongs to the grounding technology of electric power system in the field of electrician. The method comprises the following steps of firstly digging a ring-shaped pit with an isosceles trapezoid cross section in soil, paving a coke layer on the bottom of the ring-shaped pit, embedding the direct current groundingpole over the coke layer and laying a coke layer with the same thickness as the below space of the grounding pole over the direct current grounding pole; and then paving an soil layer over the coke layer, paving an insulation layer over the soil layer, and finally back-filling the soil over the insulation layer so as to lead the soil to be flat with the surrounding ground. The method for laying the direct current grounding pole provided by the invention has the advantage that the laying process is simple and easy to be operated, and the step voltage of the direct current grounding pole can bereduced by only adding a layer of insulation layer in the process of paving the direct current grounding pole. The laying method does not enlarge the occupied area of the direct current grounding pole, does not increase the size of the grounding pole, nor increases the construction cost, thereby needing less investment in economy compared with the existing laying method.

The invention discloses a voltage-sharing method for a main grounding network of a transformer station, and the method is used for solving a problem of grounding safety. The method is characterized in that the method comprises the following steps: (1), measuring the soil resistivity of the transformer station, and carrying out the structural design of a grounding network; (2), calculating the distribution condition of ground potential rise, and adding a grounding electrode at a corner of the grounding network with the most uneven distribution of ground potential rise; (3), determining the parameter of the grounding electrode, enabling the grounding electrode to be connected to the grounding network, and then carrying out the new calculation till a contact voltage and a step voltage reach set values. According to the invention, the corner of the grounding network is provided with the grounding electrode, and the grounding electrode can effectively reduce the distribution unevenness of the ground potential, thereby effectively reducing the contact voltage and the step voltage, and improving the safety of the grounding network.

The invention relates to a substation grounding grid in frozen earth area and a design method thereof and belongs to the technical field of substation construction. The grounding grid is a mesh structure in which a plurality of horizontal trunk lines and longitudinal trunk lines are connected, and the grounding grid includes a horizontal grounding grid and a sinking grounding grid where the edge of the horizontal grounding grid is bent downwards. The horizontal grounding grid is located in a frozen earth layer. The lowermost end of the sinking grounding grid is located below the frozen earth layer; and the intersections of the horizontal trunk lines and the longitudinal trunk lines are connected with grounding resistors in the downward directions, and the lowermost ends of the grounding resistors extend below the frozen earth layer. The invention optimizes the structure of the grounding grid, and reduces the stepping voltage and the contact potential of the grounding grid, thereby meeting the safety performance requirements of the grounding grid in areas with high soil resistivity and deep seasonal frozen earth. The invention does not need to increase the amount of material of thegrounding grid, does not need to expand the land acquisition area of the grounding grid and does not use additional chemical resistance-reducing substances, and reduces the investment of the project.