High-capacity skid-mounted transformer substation

Abstract

The invention provides a high-capacity skid-mounted transformer substation, which comprises a high-capacity transformer prefabricated cabin module, switch equipment, a secondary combination equipment prefabricated cabin module and semi-closed gas metal closed switch equipment, wherein the large-capacity transformer prefabricated cabin module adopts divisor and control of high current density, high magnetic density, small transformer body and low oil quantity, so that the size and the weight are reduced; the secondary combination equipment prefabricated cabin module adopts a modular design, and primary equipment is monitored and organized to operate orderly; the semi-closed gas metal-enclosed switchgear has a shock-absorbing and noise-isolating design with cost and effect integrated, and the semi-closed gas metal-enclosed switchgear is arranged at the top of the switchgear and the top of the secondary combination equipment prefabricated cabin in a modular combination mode. Therefore, the high-capacity skid-mounted transformer substation meets the requirements of light weight, miniaturization, reliability, rapidness, maneuverability, intelligence and long service life.

Description

Technical Field

[0001] The present application relates to the technical field of substations, and in particular to a large-capacity skid-mounted substation. Background Art

[0002] Electricity is an important basic energy source for sustainable social and economic development. With the rapid development of my country's economy and society, the dependence on electric energy is increasing, and the requirements for power supply continuity are also increasing. In order to meet the urgent need for power supply and power protection in modern urban power grids, emergency rescue and disaster relief, technical transformation and overhaul of substation equipment, load transfer, large-scale engineering construction, frequent migration of power loads, and other scenarios, the power system often requires large-capacity, high-reliability, high-efficiency, low-investment, and easy-to-operate temporary power supply equipment to meet the power supply needs.

[0003] Mobile substations have the characteristics of high integration, fast construction speed, small footprint, small equipment size, low construction investment, flexible assembly method, easy transportation, and quick installation. They can provide high-quality and high-reliability power supply services in scenarios where power supply is urgently needed. It is a low-cost, high-efficiency, and intelligent power supply solution in a limited space, with broad application prospects and a broad market space.

[0004] In recent years, the power industry has increased the research and application of mobile substations. Currently, there are two main forms: vehicle-mounted mobile substations and skid-mounted mobile substations. The vehicle-mounted mobile substations widely used in the industry integrate the primary and secondary equipment and other accessories of the substation into one or more semi-trailer transport vehicles to achieve mobility. Although it is convenient to transport and can arrive at the site immediately when continuous power supply is required, and can be connected to the system for use in a short time, it has defects such as low voltage level, small vehicle-mounted transformer capacity, difficulty in reaching the conventional capacity of urban power grids, high difficulty in tram integration, narrow gaps between equipment, difficult operation and maintenance, high performance requirements for transport vehicles, and high vehicle maintenance costs. It cannot fully meet the requirements of the urgency and reliability of power supply for temporary short-term power needs such as emergency rescue and disaster relief in modern urban power grids, and also hinders the growth and development of the mobile substation industry.

[0005] Therefore, a skid-mounted mobile intelligent substation equipment that can be quickly deployed, put into operation quickly, is easy to assemble and disassemble, has large capacity, is movable, highly reliable, efficient, low-investment, and easy to operate, can achieve the goal of technological integration of the complete equipment configuration of a large-capacity substation, the flexibility of a skid-mounted mobile structure, and the digital intelligence of a smart substation. It has become an urgent task for the power supply and power security needs of the power system, and is of great strategic significance for making up for the shortcomings and deficiencies of vehicle-mounted mobile substations and improving the emergency rescue capabilities and power supply reliability of the power system. Summary of the invention

[0006] In view of this, an embodiment of the present application provides a large-capacity skid-mounted substation to solve the technical defects existing in the prior art.

[0007] According to a first aspect of an embodiment of the present application, a large-capacity skid-mounted substation is provided, comprising a large-capacity transformer prefabricated cabin module, a switchgear, a secondary combination equipment prefabricated cabin module and a semi-enclosed gas metal-enclosed switchgear, wherein: The large-capacity transformer prefabricated cabin module adopts forced oil circulation air cooling, E-class insulation medium heat resistance design, and improves transformer winding current density and core magnetic flux density, reduces the amount of structural steel plates, adopts dry capacitor bushings, cancels the riser and riser CT, adopts V-type on-load tap changer, reduces transformer body size, reduces switch weight and oil consumption; The secondary combined equipment prefabricated cabin module includes a station control layer module, an interval layer module, a main transformer interval layer module, a process layer module, an AC / DC power supply module, a battery module, a communication module, and a metering module; The semi-enclosed gas-metal-enclosed switchgear adopts shock-absorbing pads of preset sizes to reduce vibration and noise in a manner of half-laying the force-bearing contact area, and the semi-enclosed gas-metal-enclosed switchgear is arranged on the top of the prefabricated cabin of the switchgear and the secondary combination equipment in a modular combination manner.

[0008] Optionally, the large-capacity skid-mounted substation further includes a prefabricated cabin, wherein: The prefabricated cabin body is composed of a cabin body frame and a sealing plate, a door plate and a top cover installed on the cabin body frame. The cabin body frame is made of carbon structural steel and is a welded one-piece structure. The top cover is connected to the upper part of the cabin body frame by high-strength bolts.

[0009] Optionally, the prefabricated cabin meets preset requirements for mechanical impact resistance, wherein the mechanical impact resistance test method of the prefabricated cabin is to apply preset accelerations in the horizontal front and rear directions, horizontal left and right directions, and vertical up and down directions of the prefabricated cabin, respectively, to obtain a deformation distribution cloud map of the prefabricated cabin, and determine the mechanical impact resistance of the prefabricated cabin according to the deformation distribution cloud map.

[0010] Optionally, the anti-corrosion treatment of the metal materials used for the prefabricated cabin and roof is achieved through the steps of sandblasting, dust blowing, arc hot zinc spraying, cooling, external spraying of epoxy zinc-rich primer and epoxy micaceous iron mid-coat, drying, sanding, dust blowing, spraying of acrylic polyurethane topcoat, and drying.

[0011] Optionally, the prefabricated cabin roof adopts an inner and outer double-layer metal plate to wrap a steel frame, and the frame gap is filled with a thermal insulation and flame retardant material with a low thermal conductivity coefficient. The thickness of the thermal insulation material is determined by calculating the steady-state heat conduction model of a single-layer flat wall.

[0012] Optionally, the prefabricated cabin adopts the thermal insulation technology to block the heat transfer through anti-cold bridge rivets and anti-cold bridge purlins.

[0013] Optionally, the prefabricated cabin panel adopts a maze design. Specifically, the panel is a modular mortise and tenon structure, and its symmetrical ends are respectively a wedge-shaped groove and a wedge-shaped boss. Different panels are spliced ​​through the wedge-shaped grooves and the wedge-shaped bosses, fixed by rivets, and sealant or sealing strips are applied to the joints, and a cover plate is added above the joints.

[0014] Optionally, the large-capacity skid-mounted substation further includes a lightning protection device, wherein: The lightning protection device comprises a single lightning rod or two lightning rods of unequal heights, wherein the single lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module, and the single lightning rod is on the highest point plane of the large-capacity skid-mounted substation, and the protection radius of the single lightning rod covers the farthest point of the large-capacity skid-mounted substation; The double-branch unequal-height lightning rod comprises a high-branch lightning rod and a low-branch lightning rod. The high-branch lightning rod is arranged at the end point of the gantry, and the low-branch lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module. On the highest point plane of the large-capacity skid-mounted substation, the equivalent midpoint of the line connecting the high-branch lightning rod and the low-branch lightning rod is greater than the width of the large-capacity transformer prefabricated cabin module.

[0015] The large-capacity skid-mounted substation provided in the present application includes a large-capacity transformer prefabricated cabin module, a switchgear, a secondary combination equipment prefabricated cabin module and a semi-enclosed gas metal-enclosed switchgear, wherein the large-capacity transformer prefabricated cabin module adopts a forced oil circulation air cooling method, an E-class insulation medium heat-resistant design, and improves the transformer winding current density and the core magnetic flux density, reduces the amount of structural steel plates, adopts a dry capacitor bushing, cancels the riser and the riser CT, adopts a V-type on-load tap changer, reduces the transformer body size, and reduces the switch weight and oil consumption; the secondary combination equipment prefabricated cabin module includes a station control layer module, an interval layer module, a main transformer interval layer module, a process layer module, an AC / DC power supply module, a battery module, a communication module, and a metering module; the semi-enclosed gas metal-enclosed switchgear adopts a shock-absorbing pad of a preset size to reduce vibration and noise in a manner of semi-paving and fitting the force contact area, and the semi-enclosed gas metal-enclosed switchgear is arranged on the top of the switchgear and the secondary combination equipment prefabricated cabin in a modular combination manner. It has achieved compact transformer weight reduction, equipment shock absorption and isolation, mechanical impact resistance verification, cabin roof anti-corrosion, rapid layout of lightning protection devices, modular design of secondary equipment, and skid-mounted transformer digital twin, making the large-capacity skid-mounted substation meet the requirements of lightweight, miniaturization, reliability, speed, mobility, intelligence and long life. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 It is a schematic diagram of a large-capacity skid-mounted substation provided in one embodiment of the present application; Figure 2 This is a layout diagram of a single lightning rod of a large-capacity skid-mounted substation provided by an embodiment of the present application; Figure 3 This is a layout diagram of double unequal height lightning rods for a large-capacity skid-mounted substation provided by an embodiment of the present application; Figure 4 This is a flow chart for constructing a digital twin of a large-capacity skid-mounted substation provided in one embodiment of the present application. DETAILED DESCRIPTION

[0018] Many specific details are described in the following description to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present application, so the present application is not limited by the specific implementation disclosed below.

[0019] The terms used in one or more embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit one or more embodiments of the present application. The singular forms of "a", "said" and "the" used in one or more embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used in one or more embodiments of the present application refers to and includes any or all possible combinations of one or more associated listed items.

[0020] It should be understood that, although the terms first, second, etc. may be used to describe various information in one or more embodiments of the present application, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of one or more embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first.

[0021] In the present application, a large-capacity skid-mounted substation is provided, including a large-capacity transformer prefabricated cabin module, a switchgear, a secondary combination equipment prefabricated cabin module and a semi-enclosed gas metal-enclosed switchgear, wherein: The large-capacity transformer prefabricated cabin module adopts forced oil circulation air cooling, E-class insulation medium heat resistance design, and improves transformer winding current density and core magnetic flux density, reduces the amount of structural steel plates, adopts dry capacitor bushings, cancels the riser and riser CT, adopts V-type on-load tap changer, reduces transformer body size, reduces switch weight and oil consumption; The secondary combined equipment prefabricated cabin module includes a station control layer module, an interval layer module, a main transformer interval layer module, a process layer module, an AC / DC power supply module, a battery module, a communication module, and a metering module; The semi-enclosed gas-metal-enclosed switchgear adopts shock-absorbing pads of preset sizes to reduce vibration and noise in a manner of half-laying the force-bearing contact area, and the semi-enclosed gas-metal-enclosed switchgear is arranged on the top of the prefabricated cabin of the switchgear and the secondary combination equipment in a modular combination manner.

[0022] It should be noted that compared with small-capacity and low-voltage skid-mounted integrated substations, the design of large-capacity skid-mounted substations needs to take into account the lightweight, miniaturization, reliability, speed, mobility, intelligence and long life of the equipment, and the requirements for the overall structure of the equipment are more stringent in terms of earthquake resistance, impact resistance and corrosion resistance. Therefore, it is necessary to ensure the lightweight design of large-capacity transformers and the shock-absorbing and seismic isolation design of semi-enclosed gas metal-enclosed switchgear.

[0023] Based on this, taking 110kV transformer as an example, Figure 1 As shown in the schematic diagram of a large-capacity skid-mounted substation provided, the large-capacity transformer prefabricated cabin module adopts the 110kV transformer prefabricated cabin module, the switchgear adopts the 10kV switchgear, and the semi-enclosed gas metal-enclosed switchgear adopts the 110kV semi-enclosed gas metal-enclosed switchgear. The overall structure of the substation is an upper and lower three-dimensional structure. Through modular combination, the semi-enclosed gas metal-enclosed switchgear, that is, the HGIS switchgear, is placed on the top of the 10kV switchgear and secondary combination equipment prefabricated cabin.

[0024] In actual use scenarios, the transformer capacity is proportional to its volume. Usually, the total weight of a 63MVA transformer after oil filling is about 70 tons, which exceeds the requirement of the existing safety principle that the total mass of road transport vehicles and cargo should not exceed 55t. In order to avoid over-limit transportation and improve the efficiency of frequent transportation and transfer of large-capacity skid-mounted substations, transformers with a total mass limit lower than the maximum allowable limit for road transportation should be provided as much as possible. Therefore, the transformer needs to be lightweight designed to reduce weight and size. Therefore, the forced oil circulation air cooling method and the E-class insulation medium heat-resistant design are adopted to increase the transformer winding current density to 5A / mm 2, increase the core flux density to 1.4T, optimize the oil tank and oil pillow design, reduce the amount of steel plates used in structural parts such as the oil tank and clamps, optimize the lead design, use dry capacitor bushings for the bushing, lead them out from the bottom of the transformer, cancel the riser and riser CT, use V-type on-load tap changers, reduce the size of the transformer body, reduce the weight of the switch and the amount of oil used, and at the same time, the transformer oil can also be set to be transported separately. According to the measured data, the above scheme reduces the original conventional 70 tons of 110kV / 63MVA transformer to about 45 tons.

[0025] The volume of the 110kV transformer prefabricated cabin module is also reduced by reducing its weight. Figure 1 As shown, the length × width × height of the 110kV transformer prefabricated cabin module is compressed to 9.84m × 10.04m × 8.0m, and the combined dimensions of the 10kV switchgear, secondary combination equipment prefabricated cabin module and the 110kV semi-enclosed gas metal-enclosed switchgear are 14.5m × 3.4m × 6.45m.

[0026] In addition, since the HGIS switchgear is connected to the 10kV switchgear and the secondary combination equipment prefabricated cabin module through the steel structure platform at the bottom, the opening and closing operations of the HGIS switchgear will affect the safe and stable operation of the microcomputer protection device and the 10kV circuit breaker in the lower prefabricated cabin. Therefore, it is necessary to carry out vibration reduction and seismic isolation design on the HGIS switchgear, such as Figure 1 As shown, the total mass of the HGIS switchgear in this embodiment is 3.6t, that is, the static load is 36kN, the dynamic load is 9kN, and the total dynamic load when the device is switched on and off is 45kN.

[0027] Then, the steel structure platform at the bottom of the HGIS switchgear is a welded part, which is welded with Q235-A rectangular tubes with dimensions of 100mm (length) × 50mm (width) × 4mm (height). The force-bearing area of ​​the platform and the HGIS installation surface is 1878800mm 2 Then, according to the static load data of the semi-enclosed gas metal-enclosed switchgear and the force-bearing area between the semi-enclosed gas metal-enclosed switchgear and the steel structure platform, the corresponding static load pressure can be calculated. The calculation formula is static load pressure = static load data / force-bearing area. Similarly, the total dynamic load pressure is calculated according to the total dynamic load data and the force-bearing area. The calculation formula is total dynamic load pressure = total dynamic load data / force-bearing area.

[0028] Then, according to the maximum static load pressure and the maximum dynamic load pressure that the shock-absorbing pad can withstand, calculate the static load stress area corresponding to the shock-absorbing pad when it withstands the ultimate pressure. The calculation formula is static load stress area = static load data / maximum static load pressure. Similarly, the dynamic load stress area corresponding to the shock-absorbing pad when it withstands the ultimate pressure can also be calculated. The calculation formula is dynamic load stress area = total dynamic load data / maximum dynamic load pressure. Select a shock-absorbing pad that meets the maximum value of the static load stress area and the dynamic load stress area. The optimal one should ensure that half of the above stress area is met. Figure 1 As shown, in this embodiment, cost, practicality, construction convenience and isolation rate are comprehensively considered, and a 25mm thick shock-absorbing pad is half-laid to fit the force contact area, achieving a 94% to 97% isolation rate and a 25 to 30dB reduction in operating noise.

[0029] The traditional substation electrical secondary equipment requires on-site wiring and debugging, which is a large workload and affects the construction period. Therefore, in this embodiment, the secondary combined equipment prefabricated cabin module is constructed through the station control layer module, the bay layer module, the main transformer bay layer module, the process layer module, the AC and DC power supply module, the battery module, the communication module, and the metering module to realize the protection configuration, measurement and control configuration, fault information configuration, safety configuration, monitoring configuration, metering configuration, power supply and communication configuration, etc.

[0030] More specifically, the station control layer module includes a monitoring host cabinet, a telecontrol and public cabinet, and a dispatching data network cabinet. The monitoring host cabinet includes a monitoring host, a display, a printer, and secondary security equipment. The monitoring host is equipped with special operating software, five-defense software, etc. The telecontrol and public cabinets include telecontrol communication equipment, public measurement and control devices, communication management devices, and clock synchronization devices. The dispatching data network cabinet includes routers, vertical encryption authentication devices, and network security monitoring devices. The interval layer module is a 110kV line protection and measurement and control cabinet, including a 110kV line protection device and a 110kV line measurement and control device. The main transformer interval layer module includes a 110kV main transformer protection cabinet and a 110kV main transformer measurement and control cabinet, wherein the 110kV main transformer protection cabinet includes differential, high backup, low backup, non-electrical protection and an operation box, and the 110kV main transformer measurement and control cabinet includes main transformer high and low voltage side measurement and control, main body measurement and control, non-electrical measurement and control, on-load voltage regulation gear controller, and main transformer temperature controller. The process layer module is a GIS control cabinet, including 110kV line current, voltage circuit, circuit breaker, disconnector, grounding switch operation, signal, and indication circuit. The AC / DC power supply module includes an AC / DC power supply panel and a DC charging and feeding panel, wherein the AC / DC power supply panel includes incoming and outgoing line circuit breakers, dual power conversion switches, inverter power supplies, and electric energy meters, and the DC charging and feeding panel includes incoming and outgoing line circuit breakers, charging modules, communication power modules, integrated monitors, and DC insulation monitoring devices. The battery module is a battery panel, including batteries and battery inspection devices. The communication module is a communication equipment cabinet, including optoelectronic integrated equipment, wiring equipment, and dispatch telephones. The metering module is a metering cabinet, including electric energy meters and electric energy collection devices. The modules of the interval layer are dispersedly arranged in the secondary compartment of the 10kV switchgear cabinet, and each module panel cabinet is arranged close to the cabin.

[0031] Therefore, the modular design of the prefabricated cabin module of the secondary combination equipment can realize large-scale production, integrated debugging, and module distribution within the factory, which can effectively reduce on-site electrical work, improve construction quality, and shorten construction period.

[0032] Furthermore, the large-capacity skid-mounted substation also includes a prefabricated cabin, wherein the prefabricated cabin is composed of a cabin frame and a sealing plate, a door panel and a top cover installed on the cabin frame, the cabin frame is made of carbon structural steel and is a welded one-piece structure, and the top cover is connected to the upper part of the cabin frame by high-strength bolts.

[0033] Furthermore, the prefabricated cabin meets preset requirements for mechanical impact resistance, wherein the mechanical impact resistance test method of the prefabricated cabin is to apply preset accelerations in the horizontal front and rear directions, horizontal left and right directions, and vertical up and down directions of the prefabricated cabin, respectively, to obtain a deformation distribution cloud map of the prefabricated cabin, and determine the mechanical impact resistance of the prefabricated cabin based on the deformation distribution cloud map.

[0034] Among them, according to the actual needs of power supply, large-capacity skid-mounted substations will be frequently transported and transferred. In order to reduce the bumps and vibrations caused during transportation and the damage to the high-voltage switchgear and microcomputer protection equipment in the prefabricated cabin modules of the switchgear and secondary combination equipment, the cabin is required to have sufficient mechanical strength and rigidity to withstand the mechanical impact caused by vehicle emergency braking, sharp turns and road bumps during transportation.

[0035] Based on this, the prefabricated cabin consists of a cabin frame and sealing panels, door panels and top covers installed on the frame. The cabin frame, including a movable or draggable sled-type bottom frame and upper frame, is made of high-quality carbon structural steel and a welded one-piece structure. The top cover and the upper frame are connected by high-strength bolts. According to the strength and rigidity requirements of large-capacity skid-mounted transformers that can be frequently moved or dragged, in actual use scenarios, the entire cabin should have sufficient mechanical strength, hardness and yield strength to enable the cabin to withstand mechanical impacts of 3g acceleration in the horizontal front and rear, horizontal left and right directions, and 2g acceleration in the vertical up and down directions.

[0036] In order to verify the cabin's ability to resist mechanical impact, ANSYS finite element analysis software was used to apply 3g acceleration in the horizontal front and rear direction and horizontal left and right direction of the prefabricated cabin, and 2g acceleration in the vertical up and down direction, to obtain the deformation distribution cloud diagram of the prefabricated cabin under impact loads in various directions. Subsequently, the maximum deformation and deformation position of the prefabricated cabin under horizontal front and rear impact loads, the maximum deformation and deformation position of the prefabricated cabin under horizontal left and right impact loads, and the maximum deformation and deformation position of the prefabricated cabin under vertical up and down impact loads were judged to see whether the ratio of the deformation of the bending member to the length of the member is less than 1 / 400. If so, the mechanical impact resistance is qualified, and if not, the mechanical impact resistance is unqualified.

[0037] Furthermore, the anti-corrosion treatment of the metal materials used for the prefabricated cabin and the roof is achieved through the steps of sandblasting, dust blowing, arc hot zinc spraying, cooling, external spraying of epoxy zinc-rich primer and epoxy micaceous iron mid-coat, drying, sanding, dust blowing, spraying of acrylic polyurethane topcoat, and drying.

[0038] Furthermore, the roof of the prefabricated cabin body adopts a steel frame wrapped with inner and outer double-layer metal plates, and the gaps in the frame are filled with thermal insulation and flame retardant materials with low thermal conductivity. The thickness of the thermal insulation material is determined by calculating the steady-state heat conduction model of a single-layer flat wall.

[0039] Furthermore, the prefabricated cabin adopts the thermal insulation technology to block the heat transfer through the anti-cold bridge rivets and anti-cold bridge purlins.

[0040] Furthermore, the prefabricated cabin panel adopts a maze design. Specifically, the panel is a modular mortise and tenon structure, and its symmetrical ends are respectively a wedge-shaped groove and a wedge-shaped boss. Different panels are spliced ​​through the wedge-shaped grooves and the wedge-shaped bosses, fixed by rivets, and sealant or sealing strips are applied to the joints, and a cover plate is added above the joints.

[0041] Among them, the large-capacity skid-mounted substation as a whole belongs to the light steel structure system. The prefabricated cabin frame adopts equal-section solid-web rigid frame, and the prefabricated cabin roof adopts corrugated steel plate and cold-bent thin-walled steel strips. Due to the inherent properties of the metal material itself, the corrosion caused by factors such as leakage and water immersion is very harmful to the cabin roof, and it is necessary to take anti-corrosion measures and carry out relevant anti-corrosion design.

[0042] Based on this, in order to extend the service life of the skid-mounted transformer, the metal materials used for the prefabricated cabin and roof need to undergo six heavy-duty anti-corrosion treatments, including sandblasting, dust blowing, arc hot zinc spraying, cooling, external spraying of epoxy zinc-rich primer and epoxy micaceous iron mid-coat, drying, sanding, dust blowing, spraying of acrylic polyurethane topcoat, and drying. According to the measured data, the total thickness of the surface paint film of the metal material after anti-corrosion treatment can reach 220um, and it is uniform and has strong adhesion, which can make the cabin roof rust-free for 40 years in a C4 environment.

[0043] Secondly, it is necessary to take good measures to insulate the cabin roof. Since the temperature inside the prefabricated cabin is lower than the dew point temperature or the absolute humidity inside the cabin is high, the unsaturated water vapor in the air becomes saturated vapor. The air cannot accommodate too much water vapor, and the water vapor liquefies and condenses, thus forming condensation. The liquid water produced by condensation will gradually corrode the cabin roof and reduce its service life. The main reasons for the cabin temperature being lower than the dew point temperature are poor cabin insulation performance, cold bridge defects in the cabin structure, poor cabin sealing performance, moisture ingress, etc.

[0044] In order to solve the above problems, the cabin roof adopts a "two-layer sandwich" structure, that is, the steel frame is wrapped with double-layer metal plates inside and outside, and the gaps in the frame are filled with thermal insulation and flame-retardant materials with low thermal conductivity, such as rock wool and polyurethane. The thickness of the thermal insulation material is determined by the steady-state heat conduction model calculation of a single-layer flat wall. At the same time, in order to eliminate the cold bridge defects of the cabin structure, the broken bridge insulation technology is adopted, and the heat transfer channel is blocked and the heat loss is reduced by adopting design measures such as anti-cold bridge rivets and anti-cold bridge purlins. In order to enhance the sealing performance of the cabin roof and prevent rain leakage, water infiltration and draft, a labyrinth design is adopted to eliminate the gaps after the cabin panels are spliced ​​together. Each panel is designed into a modular mortise and tenon structure. For example, the right end and the upper end of the panel are wedge-shaped grooves, and the left end and the lower end are wedge-shaped bosses corresponding to the grooves. The two panels are spliced ​​together through the grooves and bosses and fixed with rivets. The labyrinth mortise and tenon structure, supplemented by applying sealant or sealing strips at the joints, and adding cover plates above the joints, can ensure that the roof of the prefabricated cabin has good sealing performance.

[0045] Furthermore, the large-capacity skid-mounted substation also includes a lightning protection device, wherein: The lightning protection device comprises a single lightning rod or two lightning rods of unequal heights, wherein the single lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module, and the single lightning rod is on the highest point plane of the large-capacity skid-mounted substation, and the protection radius of the single lightning rod covers the farthest point of the large-capacity skid-mounted substation; The double-branch unequal-height lightning rod comprises a high-branch lightning rod and a low-branch lightning rod. The high-branch lightning rod is arranged at the end point of the gantry, and the low-branch lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module. On the highest point plane of the large-capacity skid-mounted substation, the equivalent midpoint of the line connecting the high-branch lightning rod and the low-branch lightning rod is greater than the width of the large-capacity transformer prefabricated cabin module.

[0046] Conventional substations are located at fixed sites and are generally equipped with permanent lightning rods. However, large-capacity skid-mounted substations need to be moved frequently and do not have fixed sites, so it is not appropriate to install permanent lightning rods. How to quickly arrange and establish lightning protection devices that meet regulatory requirements is one of the key technologies for achieving rapid commissioning of skid-mounted substations. It is necessary to predetermine the lightning rod parameters that meet the lightning protection function of large-capacity skid-mounted substations and configure the lightning rod devices.

[0047] Based on this, for the convenience, safety and economy of layout and installation, two methods are adopted: single lightning rod and double lightning rods of unequal height. Figure 2As shown in the provided single lightning rod layout diagram of a large-capacity skid-mounted substation, the transformer prefabricated cabin truss column, that is, the truss column of the large-capacity transformer prefabricated cabin module is the highest point of the entire large-capacity skid-mounted substation. Therefore, this height is used as the height hx of the skid-mounted transformer, and its height from the ground is hx=8.0m≤60m. The single lightning rod is set at point M of the 110kV transformer prefabricated cabin truss column. When the protection radius of the lightning rod on the 8.0-meter plane, that is, the highest point plane of the large-capacity skid-mounted substation, can fully cover the farthest point N of the entire skid-mounted transformer, effective lightning protection is achieved.

[0048] Specifically, if the rolling ball radius of the third-class lightning protection building is [a, b], the minimum height of a single lightning rod is h, and the protection radius is r, then the calculation formula for the minimum height is as follows: .

[0049] For two lightning rods of unequal heights, Figure 3 As shown in the provided double-branch unequal-height lightning rod arrangement diagram of a large-capacity skid-mounted substation, the lower lightning rod is set at point C of the truss column of the prefabricated cabin of the 110kV transformer in the skid-mounted transformer, and the higher lightning rod is set at point D, the end point of the gantry. If the single-sided protection range of these two unequal-height lightning rods at a height of 8.0 meters, that is, the distance from the equivalent midpoint O of their connecting line on the plane of the highest point of the large-capacity skid-mounted substation is zero, can be greater than the width of the large-capacity transformer prefabricated cabin module, the entire skid-mounted transformer can be effectively protected against lightning.

[0050] Specifically, if point E of the transformer prefabricated cabin truss column is the equivalent midpoint O of the line connecting two lightning rods of unequal heights, the minimum configuration height of the lower lightning rod is h 低 The width of the large-capacity transformer prefabricated cabin module is c, and the width of the transformer prefabricated cabin contained in the large-capacity transformer prefabricated cabin module is d, h 低 The calculation formula is as follows: , In addition, if the distance between the high and low lightning rods is D, the minimum height of the high lightning rod is h 高 , the calculation formula is as follows: .

[0051] Furthermore, the digital twin of the substation corresponding to the large-capacity skid-mounted substation and the corresponding model framework realize the construction of health status assessment model, fault evolution characteristic model under typical defects, and output characteristic model under special working conditions through high-fidelity modeling, multi-physical field modeling, data-driven modeling, and multi-structure feature modeling, and conduct preliminary accuracy verification and update through comparison with physical parameters.

[0052] Among them, digital twin is the core content for realizing the digitization of large-capacity skid-mounted substations. Based on the twin data output by the physical entity of the large-capacity skid-mounted substation, the corresponding substation virtual entity is created to realize the visualization of the three-dimensional model of the entire digital twin virtual substation and realize real-time monitoring of the operating conditions of various equipment in the substation.

[0053] Based on this, Figure 4 As shown in the flowchart of building a digital twin of a large-capacity skid-mounted substation, the key to building a digital twin of a substation is the construction of a digital twin model, which includes not only a single model that describes the performance of a physical entity, but also an assembly model and a fusion model that comprehensively depicts the multi-angle and all-round physical entity. In order to ensure that the constructed digital twin model is more accurate and effective, a complete model framework needs to be built, which mainly includes model construction, model verification and model update. Model construction mainly models the typical characteristics of the entity, including high-fidelity modeling, multi-physics field modeling, data-driven modeling, multi-structure feature modeling, etc., so as to form a single model representing the typical characteristics of the entity, such as a health status assessment model, a fault evolution characteristic model under typical defects, and a special working condition, such as an output characteristic model under the action of multiple physical fields. In order to realize the progress of a single model towards a digital twin, the single model is assembled in layers and orderly by adding appropriate constraints in the spatial structure to build an assembly model. Based on the coupling and correlation characteristics between single models or assembly models, multi-models and multi-physics fields are fused to form a fusion model. All constructed models are initially tested for accuracy and updated by comparing with physical parameters. The assembled and fused models are combined in an orderly manner to construct the initial digital twin, and its accuracy is verified by comparing with the results of the physical entity. If the accuracy requirements are met, the final digital twin is formed through model verification; if not, it is updated through feedback from the physical entity parameters until a substation digital twin that meets the accuracy requirements is constructed.

[0054] The construction of the substation digital twin depends on computing equipment. The components of the computing equipment include but are not limited to memory and processor. The processor and memory are connected through a bus, and the database is used to store data.

[0055] The computing device also includes an access device that enables the computing device to communicate via one or more networks. Examples of these networks include a public switched telephone network (PSTN), a local area network (LAN), a wide area network (WAN), a personal area network (PAN), or a combination of communication networks such as the Internet. The access device may include one or more of any type of network interface (e.g., a network interface card (NIC)) of wired or wireless, such as an IEEE 802.11 wireless local area network (WLAN) wireless interface, a World Wide Interoperability for Microwave Access (Wi-MAX) interface, an Ethernet interface, a universal serial bus (USB) interface, a cellular network interface, a Bluetooth interface, a near field communication (NFC) interface, and the like.

[0056] In one embodiment of the present application, other components not shown in the above-mentioned components of the computing device may also be connected to each other, for example, through a bus, and those skilled in the art may add or replace other components as needed.

[0057] The computing device may be any type of stationary or mobile computing device, including a mobile computer or mobile computing device (e.g., a tablet computer, a personal digital assistant, a laptop computer, a notebook computer, a netbook, etc.), a mobile phone (e.g., a smart phone), a wearable computing device (e.g., a smart watch, smart glasses, etc.), or other types of mobile devices, or a stationary computing device such as a desktop computer or PC. The computing device may also be a mobile or stationary server.

[0058] Among them, the processor is used to execute computer executable instructions for each step of building a digital twin of a substation. An embodiment of the present application also provides a computer readable storage medium, which stores computer instructions, which are used to implement each step of building a digital twin of a substation when the instructions are executed by the processor. An embodiment of the present application also provides a chip, which stores a computer program, which implements each step of building a digital twin of a substation when the computer program is executed by the chip.

[0059] The above describes specific embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0060] The computer instructions include computer program codes, which may be in source code form, object code form, executable files or some intermediate forms, etc. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the content contained in the computer-readable medium may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0061] It should be noted that, for the above-mentioned method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described action sequence, because according to the present application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0062] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0063] The preferred embodiments of the present application disclosed above are only used to help explain the present application. The optional embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of the present application. The present application selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present application, so that those skilled in the art can understand and use the present application well. The present application is only limited by the claims and their full scope and equivalents.

Claims

1. A large-capacity skid-mounted substation, characterized in that: It includes large-capacity transformer prefabricated cabin modules, switchgear, secondary combination equipment prefabricated cabin modules and semi-enclosed gas metal-enclosed switchgear, among which: The large-capacity transformer prefabricated cabin module adopts forced oil circulation air cooling, E-class insulation medium heat resistance design, and improves transformer winding current density and core magnetic flux density, reduces the amount of structural steel plates, adopts dry capacitor bushings, cancels the riser and riser CT, adopts V-type on-load tap changer, reduces transformer body size, reduces switch weight and oil consumption; The secondary combined equipment prefabricated cabin module includes a station control layer module, an interval layer module, a main transformer interval layer module, a process layer module, an AC / DC power supply module, a battery module, a communication module, and a metering module; The semi-enclosed gas-metal-enclosed switchgear adopts shock-absorbing pads of preset sizes to reduce vibration and noise in a manner of half-laying the force-bearing contact area, and the semi-enclosed gas-metal-enclosed switchgear is arranged on the top of the prefabricated cabin of the switchgear and the secondary combination equipment in a modular combination manner.

2. A large-capacity skid-mounted substation according to claim 1, characterized in that: The large-capacity skid-mounted substation also includes a prefabricated cabin, wherein: The prefabricated cabin body is composed of a cabin body frame and a sealing plate, a door plate and a top cover installed on the cabin body frame. The cabin body frame is made of carbon structural steel and is a welded one-piece structure. The top cover is connected to the upper part of the cabin body frame by high-strength bolts.

3. A large-capacity skid-mounted substation according to claim 2, characterized in that: The prefabricated cabin meets the preset requirements for mechanical impact resistance performance, wherein the mechanical impact resistance performance testing method of the prefabricated cabin is to apply preset accelerations in the horizontal front and rear directions, horizontal left and right directions, and vertical up and down directions of the prefabricated cabin, respectively, to obtain a deformation distribution cloud map of the prefabricated cabin, and determine the mechanical impact resistance performance of the prefabricated cabin based on the deformation distribution cloud map.

4. A large-capacity skid-mounted substation according to claim 2, characterized in that: The anti-corrosion treatment of the metal materials used for the prefabricated cabin and the roof is achieved through the steps of sandblasting, dust blowing, arc hot zinc spraying, cooling, external spraying of epoxy zinc-rich primer and epoxy micaceous iron mid-coat, drying, sanding, dust blowing, spraying of acrylic polyurethane topcoat, and drying.

5. A large-capacity skid-mounted substation according to claim 2, characterized in that: The roof of the prefabricated cabin body adopts an inner and outer double-layer metal plate to wrap a steel frame, and the gaps in the frame are filled with thermal insulation and flame retardant materials with low thermal conductivity. The thickness of the thermal insulation material is determined by calculating the steady-state heat conduction model of a single-layer flat wall.

6. A large-capacity skid-mounted substation according to claim 2, characterized in that: The prefabricated cabin adopts the thermal insulation technology to block the heat transfer through the anti-cold bridge rivets and anti-cold bridge purlins.

7. A large-capacity skid-mounted substation according to claim 2, characterized in that: The prefabricated cabin panels adopt a maze design. Specifically, the panels are modular mortise and tenon structures, and their symmetrical ends are respectively wedge-shaped grooves and wedge-shaped bosses. Different panels are spliced ​​through wedge-shaped grooves and wedge-shaped bosses, fixed by rivets, and sealant or sealing strips are applied at the joints, and a cover plate is added above the joints.

8. A large-capacity skid-mounted substation according to claim 1, characterized in that: The large-capacity skid-mounted substation also includes a lightning protection device, wherein: The lightning protection device comprises a single lightning rod or two lightning rods of unequal heights, wherein the single lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module, and the single lightning rod is on the highest point plane of the large-capacity skid-mounted substation, and the protection radius of the single lightning rod covers the farthest point of the large-capacity skid-mounted substation; The double-branch unequal-height lightning rod comprises a high-branch lightning rod and a low-branch lightning rod. The high-branch lightning rod is arranged at the end point of the gantry, and the low-branch lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module. On the highest point plane of the large-capacity skid-mounted substation, the equivalent midpoint of the line connecting the high-branch lightning rod and the low-branch lightning rod is greater than the width of the large-capacity transformer prefabricated cabin module.

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