A large-capacity skid-mounted substation

Abstract

The present application provides a large-capacity skid-mounted substation, which includes a large-capacity transformer prefabricated cabin module, switchgear, a secondary combined equipment prefabricated cabin module, and a semi-enclosed gas-insulated metal-enclosed switchgear. Among them, the large-capacity transformer prefabricated cabin module adopts the control of the approximate sum of high current density, high magnetic density, small core body, and low oil volume to reduce the volume and weight; the secondary combined equipment prefabricated cabin module adopts a modular design to monitor and organize the orderly operation of primary equipment; the semi-enclosed gas-insulated metal-enclosed switchgear has a shock and noise isolation design with a comprehensive cost and effect, and the semi-enclosed gas-insulated metal-enclosed switchgear is arranged on the top of the switchgear and the secondary combined equipment prefabricated cabin in a modular combination manner. This enables the large-capacity skid-mounted substation to meet the requirements of lightweight, miniaturization, reliability, speed, mobility, intelligence, and long life.

Description

Technical Field

[0001] This application relates to the technical field of substations, and particularly to a large-capacity skid-mounted substation. Background Art

[0002] Electricity is an important basic energy source for the sustainable development of society and economy. With the rapid development of China's economic society, the dependence on electric energy is increasing, and the requirement for power supply continuity is also getting higher. To meet the urgent power supply and power protection scenarios such as emergency rescue and disaster relief of modern urban power grids, technical renovation and major overhaul of substation equipment, load transfer, large-scale engineering construction, and frequent migration of power loads, the power system often needs temporary power supply equipment with large capacity, high reliability, high efficiency, low investment, and easy operation to meet the power supply and protection requirements.

[0003] Mobile substations have the characteristics of high integration level, fast construction speed, small floor area, small equipment volume, low construction investment, flexible assembly method, convenient transportation, and fast installation. They can provide high-quality and highly reliable power supply services in urgent power supply and protection scenarios. It is a low-cost, high-efficiency, and intelligent power supply solution in a limited space, with broad application prospects and a wide market space.

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

[0005] Therefore, a skid-mounted mobile intelligent substation device that can be quickly and flexibly deployed, quickly put into operation, is convenient for assembly and disassembly, has large capacity, is movable, highly reliable, highly efficient, low investment, and easy to operate, and realizes the goal of integrating the complete equipment configuration of a large-capacity substation, the flexibility of a skid-mounted movable structure, and the digital intelligence of an intelligent substation through technological integration has become an urgent task for the power supply and protection requirements of the power system. It is of great strategic significance for making up for the shortcomings and deficiencies of vehicle-mounted mobile substations and improving the emergency response ability 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 the first aspect of the embodiment of the present application, a large-capacity skid-mounted substation is provided, including a large-capacity transformer prefabricated cabin module, switchgear, a secondary combined equipment prefabricated cabin module, and a semi-enclosed gas-insulated metal-enclosed switchgear. Among them,

[0008] The large-capacity transformer prefabricated cabin module adopts the forced oil circulation air cooling method, E-class insulating medium heat-resistant design, and improves the current density of the transformer winding and the magnetic flux density of the iron core, reduces the amount of structural steel plate, adopts dry-type capacitive bushings, cancels the riser and the riser CT, and adopts a V-type on-load tap-changer to reduce the size of the transformer body and reduce the weight of the switch and the amount of oil used;

[0009] 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;

[0010] The semi-enclosed gas-insulated metal-enclosed switchgear adopts shock pads of a preset size to perform shock isolation and noise reduction in the way of semi-paving and fitting the force contact area, and the semi-enclosed gas-insulated metal-enclosed switchgear is arranged on the top of the switchgear and the secondary combined equipment prefabricated cabin in a modular combination manner.

[0011] Optionally, the large-capacity skid-mounted substation further includes a prefabricated cabin body, where

[0012] The prefabricated cabin body is composed of a cabin body skeleton and a sealing plate, a door panel, and a top cover installed on the cabin body skeleton. The cabin body skeleton adopts carbon structural steel and is of a welded integral structure. The top cover and the upper part of the cabin body skeleton are connected by high-strength bolts.

[0013] Optionally, the prefabricated cabin body meets the requirements of the preset anti-mechanical shock performance. Among them, the anti-mechanical shock performance test method of the prefabricated cabin body is to apply a preset acceleration in the horizontal front-back direction, horizontal left-right direction, and vertical up-down direction of the prefabricated cabin body respectively to obtain the deformation amount distribution cloud map of the prefabricated cabin body, and determine the anti-mechanical shock performance of the prefabricated cabin body according to the deformation amount distribution cloud map.

[0014] Optionally, the anti-corrosion treatment of the metal materials used for the prefabricated cabin body and the roof is realized through the processes of sandblasting, dust blowing, arc thermal spraying of zinc, cooling, external spraying of epoxy zinc-rich primer and epoxy mica iron intermediate paint, drying, grinding and roughening, dust blowing, and spraying of acrylic polyurethane topcoat, and drying.

[0015] Optionally, the top of the prefabricated cabin is wrapped with a double-layer metal plate inside and outside, covering a steel skeleton. The voids in the skeleton are filled with thermal insulation and fire-retardant materials with low thermal conductivity. The thickness of the thermal insulation material is determined by calculating through the steady-state heat conduction model of a single-layer flat wall.

[0016] Optionally, the prefabricated cabin adopts the technology of broken bridge heat insulation, and through cold bridge prevention rivets and cold bridge prevention purlins, the heat transfer is blocked.

[0017] Optionally, the plate components of the prefabricated cabin adopt a labyrinth design. Specifically, the plate components are modular tenon and mortise structures. The two symmetrical ends are respectively a wedge-shaped groove and a wedge-shaped boss. Different plate components are spliced through the wedge-shaped groove and the wedge-shaped boss, fixed by rivets, and sealant is applied or sealant strips are pasted at the joints. A cover plate is additionally arranged above the joints.

[0018] Optionally, the large-capacity skid-mounted substation further includes a lightning protection device, wherein,

[0019] The lightning protection device includes a single lightning rod or two unequal-height lightning rods. The single lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module, and the single lightning rod, on the plane of the highest point of the large-capacity skid-mounted substation, has a protection radius covering the farthest point of the large-capacity skid-mounted substation;

[0020] The two unequal-height lightning rods include a high lightning rod and a low lightning rod. The high lightning rod is arranged at the end point of the gantry, and the low lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module. On the plane of the highest point of the large-capacity skid-mounted substation, the equivalent midpoint of the connection line between the high lightning rod and the low lightning rod is greater than the width of the large-capacity transformer prefabricated cabin module.

[0021] The large-capacity skid-mounted substation provided by this application includes a large-capacity transformer prefabricated cabin module, switchgear, secondary combined equipment prefabricated cabin module, and semi-enclosed gas-insulated switchgear. Among them, the large-capacity transformer prefabricated cabin module adopts the forced oil circulation air-cooling method, E-class insulation medium heat-resistant design, improves the current density of the transformer winding and the magnetic flux density of the iron core, reduces the amount of structural steel plate, adopts dry-type capacitive bushings, cancels the riser and the riser CT, adopts a V-type on-load tap-changer, reduces the size of the transformer body, and reduces the weight of the switch and the amount of oil used; 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-insulated switchgear adopts shock pads of a preset size to carry out shock absorption and noise isolation in the way of semi-paving and fitting the force contact area, and the semi-enclosed gas-insulated switchgear is arranged on the top of the switchgear and the secondary combined equipment prefabricated cabin in a modular combination manner. It realizes the compact weight reduction of the transformer, the shock absorption and isolation of equipment, the verification of anti-mechanical shock, the anti-corrosion of the cabin roof, the rapid layout of lightning protection devices, the modular design of secondary equipment, and the digital twin of skid-mounted transformers, making the large-capacity skid-mounted substation meet the requirements of light weight, small size, reliability, speed, mobility, intelligence and long life. Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments of this application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0023] Figure 1 It is a schematic diagram of a large-capacity skid-mounted substation provided by an embodiment of this application;

[0024] Figure 2 It is an arrangement diagram of a single lightning rod of a large-capacity skid-mounted substation provided by an embodiment of this application;

[0025] Figure 3 It is an arrangement diagram of two unequal-height lightning rods of a large-capacity skid-mounted substation provided by an embodiment of this application;

[0026] Figure 4 It is a flowchart for constructing a digital twin of a large-capacity skid-mounted substation provided by an embodiment of this application. Detailed Embodiments

[0027] In the following description, numerous specific details are set forth to provide a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present application. Therefore, the present application is not limited by the specific implementations disclosed below.

[0028] The terms used in one or more embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit one or more embodiments of the present application. The singular forms "a", "the", and "said" used in one or more embodiments of the present application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in one or more embodiments of the present application refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0029] It should be understood that although the terms first, second, etc. may be used in one or more embodiments of the present application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type 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.

[0030] In the present application, a large-capacity skid-mounted substation is provided, including a large-capacity transformer prefabricated cabin module, switchgear, a secondary combined equipment prefabricated cabin module, and a semi-enclosed gas-insulated metal-enclosed switchgear, wherein,

[0031] The large-capacity transformer prefabricated cabin module adopts the forced oil circulation air cooling method, E-class insulation medium heat-resistant design, and improves the transformer winding current density and core magnetic flux density, reduces the amount of structural steel plate used, adopts dry-type capacitive bushings, cancels the riser and riser CT, adopts a V-type on-load tap-changer, reduces the size of the transformer body, and reduces the switch weight and oil consumption;

[0032] 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;

[0033] The semi-enclosed gas-insulated metal-enclosed switchgear adopts shock pads of a preset size to perform shock absorption and noise isolation in the way of semi-paving and fitting the force contact area, and the semi-enclosed gas-insulated metal-enclosed switchgear is arranged on the top of the switchgear and the secondary combined equipment prefabricated cabin in a modular combination manner.

[0034] It should be noted that compared with the skid-mounted integrated substation with small capacity and low voltage, when designing a large-capacity skid-mounted substation, it is necessary to consider the lightweight, miniaturization, reliability, speed, mobility, intelligence and long life of the equipment, and the requirements for the seismic resistance, shock resistance and corrosion resistance of the overall structure of the equipment are also more stringent. Therefore, it is necessary to ensure the lightweight design of the large-capacity transformer and the shock absorption and isolation design of the semi-enclosed gas metal-enclosed switchgear.

[0035] Based on this, taking the 110kV transformer as an example, as Figure 1 shown in the schematic diagram of a large-capacity skid-mounted substation provided, the prefabricated cabin module of the large-capacity transformer 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 up-and-down 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 the prefabricated cabin of the secondary combined equipment.

[0036] In the actual use scenario, the transformation capacity of the transformer is proportional to its volume. Usually, the total weight of a 63MVA capacity transformer after filling with oil is about 70 tons, which exceeds the requirement that the total mass of the road transport vehicle should not exceed 55t stipulated in the existing safety principles. 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 lower than the maximum allowable total mass limit of road transportation should be provided as much as possible. Therefore, it is necessary to carry out lightweight design on the transformer to reduce the weight and volume. Therefore, by adopting the forced oil circulation air cooling method and the E-class insulation medium heat resistance design, the current density of the transformer winding is increased to 5A / mm 2 , the core magnetic flux density is increased to 1.4T, the design of the oil tank and oil conservator is optimized, the steel plate usage of structural parts such as the oil tank and clamping parts is reduced, the lead wire design is optimized, the bushing adopts a dry-type capacitive bushing, which is led out from the bottom of the transformer, the riser and the riser CT are cancelled, the V-type on-load tap-changer is adopted, the size of the transformer body is reduced, the weight of the switch and the oil usage are reduced, etc. At the same time, the transformer oil can also be set for separate transportation. According to the measured data, the above scheme reduces the original conventional 110kV / 63MVA transformer of about 70 tons to about 45 tons.

[0037] Through the 110kV transformer prefabricated cabin module after weight reduction, its volume is also reduced synchronously. As Figure 1 shown, the length × width × height of the 110kV transformer prefabricated cabin module is compressed to 9.84m × 10.04m × 8.0m, and the combined external dimensions of the 10kV switchgear, the prefabricated cabin module of the secondary combined equipment and the 110kV semi-enclosed gas metal-enclosed switchgear are 14.5m × 3.4m × 6.45m.

[0038] In addition, since the HGIS switchgear is connected to the 10kV switchgear and the prefabricated cabin module of the secondary combined equipment through the steel structure platform at the bottom, when the HGIS switchgear is switched on and off, it 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 design shock absorption and vibration isolation for the HGIS switchgear. For example, 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 during equipment switch operation is 45kN.

[0039] Then, the steel structure platform at the bottom of the HGIS switchgear is a welded part, welded with Q235-A rectangular tubes with dimensions of 100mm (length) × 50mm (width) × 4mm (height). The stress area of the platform in contact with the HGIS installation is 1878800mm 2 Therefore, according to the static load data of the semi-enclosed gas-insulated metal-enclosed switchgear and the stress area between the semi-enclosed gas-insulated 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 / stress area. Similarly, the total dynamic load pressure is calculated based on the total dynamic load data and the stress area, and the calculation formula is total dynamic load pressure = total dynamic load data / stress area.

[0040] Subsequently, according to the maximum static load pressure and maximum dynamic load pressure that the shock pad can withstand, the static load stress area corresponding to the limit pressure of the shock pad is calculated. The calculation formula is static load stress area = static load data / maximum static load pressure. Similarly, the dynamic load stress area corresponding to the limit pressure of the shock pad can also be calculated, and the calculation formula is dynamic load stress area = total dynamic load data / maximum dynamic load pressure. Select a shock pad that satisfies being greater than the maximum value of the static load stress area and the dynamic load stress area. Optimally, it should ensure to satisfy half of the above stress area. For example, Figure 1 As shown, in this embodiment, considering the comprehensive cost, practicability, construction convenience, and vibration isolation rate, the method of using a 25mm-thick shock pad to semi-pave and fit the stress contact area achieves a vibration isolation rate of 94% - 97% and the effect of reducing the operation noise by 25 - 30dB.

[0041] Traditional electrical secondary equipment in substations requires on-site wiring and commissioning, with a large workload, which affects the construction period. Therefore, in this embodiment, a prefabricated cabin module for secondary combined equipment is constructed through the station control layer module, bay layer module, main transformer bay layer module, process layer module, AC / DC power supply module, battery module, communication module, and metering module to achieve protection configuration, measurement and control configuration, fault information configuration, security configuration, monitoring configuration, metering configuration, power supply and communication configuration, etc.

[0042] More specifically, the station control layer module includes a monitoring main cabinet, a telecontrol and common cabinet, and a dispatching data network cabinet. The monitoring main cabinet contains a monitoring host, a display, a printer, and secondary security equipment. The monitoring host is equipped with dedicated operation software, five-prevention software, etc. The telecontrol and common cabinet contains telecontrol communication equipment, common measuring and control devices, communication management devices, and clock synchronization devices. The dispatching data network cabinet includes a router, a longitudinal encryption and authentication device, and a network security monitoring device. The bay layer module is an 110 kV line protection and measurement and control cabinet, including an 110 kV line protection device and an 110 kV line measurement and control device. The main transformer bay layer module includes an 110 kV main transformer protection cabinet and an 110 kV main transformer measurement and control cabinet. Among them, the 110 kV main transformer protection cabinet includes differential protection, high-backup protection, low-backup protection, non-electrical quantity protection, and an operation box. The 110 kV main transformer measurement and control cabinet includes main transformer high- and low-voltage side measurement and control, body measurement and control, non-electrical quantity measurement and control, on-load tap changer controller, and main transformer temperature controller. The process layer module is a GIS control cabinet, including 110 kV line current, voltage circuits, circuit breakers, disconnectors, earthing switch operations, signals, and indication circuits. The AC / DC power supply module includes an AC / DC power supply panel and a DC charging and feeding panel. Among them, the AC / DC power supply panel includes incoming and outgoing line circuit breakers, a dual-power conversion switch, an inverter power supply, and a watt-hour meter. The DC charging and feeding panel includes incoming and outgoing line circuit breakers, charging modules, a communication power supply module, an integrated monitor, and a DC insulation monitoring device. The battery module is a battery panel, including batteries and a battery inspection device. The communication module is a communication equipment cabinet, including optoelectronic integrated equipment, wiring equipment, and dispatching telephones. The metering module is a metering cabinet, including watt-hour meters and electric energy acquisition devices. And the bay layer modules are dispersed and arranged locally in the secondary small rooms of 10 kV switchgear cabinets, and each module panel is arranged against the cabin body.

[0043] Therefore, for the secondary combined equipment prefabricated cabin module, its modular design can achieve large-scale production, integrated commissioning, and module distribution in the factory, which can effectively reduce on-site electrical work, improve construction quality, and shorten the construction period.

[0044] Furthermore, the large-capacity skid-mounted substation further includes a prefabricated cabin body. Among them, the prefabricated cabin body is composed of a cabin body skeleton and sealing plates, door panels, and a top cover installed on the cabin body skeleton. The cabin body skeleton is made of carbon structural steel and is a welded integral structure. The top cover is connected to the upper part of the cabin body skeleton by high-strength bolts.

[0045] Furthermore, the prefabricated cabin body meets the preset requirements for anti-mechanical shock performance. Among them, the anti-mechanical shock performance test method of the prefabricated cabin body is to apply a preset acceleration in the horizontal front-back direction, horizontal left-right direction, and vertical up-down direction of the prefabricated cabin body respectively, obtain the deformation distribution nephogram of the prefabricated cabin body, and determine the anti-mechanical shock performance of the prefabricated cabin body according to the deformation distribution nephogram.

[0046] Among them, according to the actual power supply guarantee needs, large-capacity skid-mounted substations will be frequently transported and transferred. To reduce the bumps and vibrations generated during transportation and prevent damage to the high-voltage switchgear and microcomputer protection equipment in the prefabricated cabin modules of switchgear and secondary combined equipment, it is required that the cabin body has sufficient mechanical strength and stiffness to withstand the mechanical impact caused by emergency braking, sharp turning of vehicles, and road bumps during transportation.

[0047] Based on this, the prefabricated cabin body is composed of a cabin body skeleton and sealing plates, door panels, and a top cover installed on the skeleton. The cabin body skeleton includes a movable or towable sled-type bottom frame and an upper frame, which are made of high-quality carbon structural steel and welded into an integral structure. High-strength bolts are used to connect the top cover and the upper frame. According to the strength and stiffness requirements of the large-capacity skid-mounted transformer that can be frequently moved or towed, in the actual use scenario, the entire cabin body should have sufficient mechanical strength, hardness, and yield strength to enable the cabin body to withstand the mechanical impact of 3g acceleration in the horizontal front-back and horizontal left-right directions and 2g acceleration in the vertical up-down direction.

[0048] To verify the mechanical impact resistance of the cabin body, ANSYS finite element analysis software is used to apply 3g acceleration in the horizontal front-back and horizontal left-right directions of the prefabricated cabin respectively, and 2g acceleration in the vertical up-down direction to obtain the deformation distribution nephogram of the prefabricated cabin under the impact load in each direction. Subsequently, judge whether the maximum deformation amount and deformation position of the prefabricated cabin under the horizontal front-back impact load, the maximum deformation amount and deformation position of the prefabricated cabin under the horizontal left-right impact load, and the maximum deformation amount and deformation position of the prefabricated cabin under the vertical up-down impact load meet the requirement that the ratio of the deformation amount of the flexural member to the member length is less than 1 / 400. If it meets the requirement, the mechanical impact resistance is qualified; if it does not meet the requirement, the mechanical impact resistance is unqualified.

[0049] Furthermore, for the metal materials used in the prefabricated cabin body and the roof, the anti-corrosion treatment is achieved through the processes of sandblasting, dust blowing, arc thermal spraying of zinc, cooling, external spraying of epoxy zinc-rich primer and epoxy micaceous iron intermediate paint, drying, grinding and roughening, dust blowing, spraying of acrylic polyurethane topcoat, and drying.

[0050] Furthermore, the cabin top of the prefabricated cabin body is wrapped with a steel skeleton by inner and outer double-layer metal plates, and the voids in the skeleton are filled with heat-insulating and flame-retardant materials with low thermal conductivity. The thickness of the heat-insulating material is determined by calculating with the steady-state heat conduction model of a single-layer flat wall.

[0051] Furthermore, the prefabricated cabin body adopts the broken bridge heat insulation technology, and the heat transfer is blocked through cold bridge-proof rivets and cold bridge-proof purlins.

[0052] Furthermore, the prefabricated cabin panels adopt a labyrinth design. Specifically, the panels are of a modular tenon and mortise structure, with wedge-shaped grooves and wedge-shaped bosses at its symmetric two ends respectively. Different panels are spliced through the wedge-shaped grooves and wedge-shaped bosses, fixed by rivets, and sealant is applied or sealant strips are pasted at the joints. A cover plate is additionally provided above the joints.

[0053] Among them, the overall large-capacity skid-mounted substation belongs to the light steel structure system. The prefabricated cabin skeleton adopts an equal-section solid web rigid frame, and the prefabricated cabin roof adopts profiled steel sheets and cold-formed thin-walled steel purlins. Limited by the inherent properties of the metal materials themselves, corrosion caused by factors such as rain leakage and water immersion poses great harm to the cabin roof. Anti-corrosion measures need to be taken and relevant anti-corrosion designs are carried out.

[0054] Based on this, to extend the service life of the skid-mounted transformer, six heavy anti-corrosion treatments need to be carried out on the metal materials used for the prefabricated cabin and the roof, specifically sandblasting, dust blowing, arc thermal spraying of zinc, cooling, externally spraying epoxy zinc-rich primer and epoxy mica iron intermediate paint, drying, grinding and roughening, dust blowing, spraying acrylic polyurethane topcoat, and drying. According to the measured data, the total thickness of the paint film on the surface of the metal materials can reach 220um after anti-corrosion treatment, and it is uniform, with strong adhesion, which can make the cabin roof not corrode for 40 years in a C4 environment.

[0055] Secondly, heat insulation and thermal insulation measures for the cabin roof need to be taken. 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, and the air cannot accommodate too much water vapor. The water vapor liquefies and condenses out, thus forming condensation. And the liquid water generated by condensation will gradually corrode the cabin roof and reduce the service life. The main reasons for the temperature inside the cabin being lower than the dew point temperature are poor thermal insulation performance of the cabin, cold bridge defects in the cabin structure, poor sealing performance of the cabin, and entry of moisture, etc.

[0056] To solve the above problems, the cabin top adopts a "two-layer sandwich" structure, that is, the inner and outer double-layer metal plates wrap the steel skeleton, and the space of the skeleton is filled with heat-insulating and flame-retardant materials with low thermal conductivity, such as rock wool, polyurethane, etc. The thickness of the thermal insulation material is determined by calculating through the steady-state heat conduction model of a single-layer flat wall. At the same time, in terms of eliminating the cold bridge defect of the cabin structure, the broken bridge heat insulation technology is adopted. By adopting design measures such as cold bridge-proof rivets and cold bridge-proof purlins, the heat transfer channel is blocked to reduce heat loss. In terms of strengthening the sealing performance of the cabin roof to prevent rain leakage, water immersion, and ventilation, in order to eliminate the gap after the splicing of the cabin plates, a labyrinth design is adopted. Each plate is designed into a modular tenon and mortise structure. For example, the right end and the upper end of the plate are wedge-shaped grooves, and the left end and the lower end are wedge-shaped bosses corresponding to the grooves. The two plates are spliced through the grooves and bosses and fixed with rivets. Through the labyrinth tenon and mortise structure, supplemented by measures such as applying sealant or sticking sealant strips at the joints and adding a cover plate above the joints, the sealing performance of the prefabricated cabin roof can be ensured.

[0057] Furthermore, the large-capacity skid-mounted substation further includes a lightning protection device, wherein,

[0058] The lightning protection device includes a single lightning rod or two unequal-height lightning rods. The single lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module, and the single lightning rod, on the plane of the highest point of the large-capacity skid-mounted substation, has a protection radius covering the farthest point of the large-capacity skid-mounted substation;

[0059] The two unequal-height lightning rods include a high lightning rod and a low lightning rod. The high lightning rod is arranged at the end point of the gantry, and the low lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module. On the plane of the highest point of the large-capacity skid-mounted substation, the equivalent midpoint of the connection line between the high lightning rod and the low lightning rod is greater than the width of the large-capacity transformer prefabricated cabin module.

[0060] The site of a conventional substation is fixed, and permanent lightning rods are generally set; while the large-capacity skid-mounted substation needs to be moved frequently and has no fixed site, so it is not suitable to set permanent lightning rods. How to quickly arrange and establish a lightning protection device that meets the specification requirements is one of the key technologies for the skid-mounted transformer to be quickly put into operation. It is necessary to pre-determine the parameters of the lightning rod that meet the lightning protection function of the large-capacity skid-mounted substation and configure the lightning rod device.

[0061] Based on this, considering the convenience, safety, and economy of layout and installation comprehensively, two methods of a single lightning rod and two unequal-height lightning rods are adopted. For a single lightning rod, such as Figure 2As shown in the layout diagram of a single lightning rod for a large-capacity skid-mounted substation, the truss column of the transformer prefabricated cabin, 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 truss column of the 110kV transformer prefabricated cabin. 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 completely cover the farthest point N of the entire skid-mounted transformer, effective lightning protection is achieved.

[0062] Specifically, if the rolling sphere 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:

[0063] 。

[0064] For two unequal-height lightning rods, such as Figure 3 As shown in the layout diagram of two unequal-height lightning rods for a large-capacity skid-mounted substation, the lower lightning rod is set at point C of the truss column of the 110kV transformer prefabricated cabin of the skid-mounted transformer, and the higher lightning rod is set at point D at the end of the gantry. If the unilateral protection range of these two unequal-height lightning rods at a height of 8.0 meters, that is, at a distance of zero from the equivalent midpoint O of their connection line on the highest point plane of the large-capacity skid-mounted substation, is greater than the width of the large-capacity transformer prefabricated cabin module, then the entire skid-mounted transformer can obtain effective lightning protection.

[0065] Specifically, if point E of the truss column of the transformer prefabricated cabin is the equivalent midpoint O of the connection line of the two unequal-height lightning rods, the minimum configured height of the lower lightning rod is h 低 ,the width of the large-capacity transformer prefabricated cabin module is c, the width of the transformer prefabricated cabin included in the large-capacity transformer prefabricated cabin module is d, h 低 The calculation formula is as follows:

[0066] ,

[0067] In addition, if the distance between the higher and lower lightning rods is D, and the minimum configured height of the higher lightning rod is h 高 The calculation formula is as follows:

[0068] 。

[0069] Furthermore, for the substation digital twin corresponding to the large-capacity skid-mounted substation, the corresponding model framework realizes the construction of a health status assessment model, a fault evolution characteristic model under typical defects, and an output characteristic model under special working conditions through high-fidelity modeling, multi-physical field modeling, data-driven modeling, and multi-structural feature modeling, and conducts preliminary accuracy inspection and update by comparing with entity parameters.

[0070] Among them, digital twin is the core content for realizing the digitalization 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 visual presentation of the three-dimensional model of the entire digital twin virtual substation and the real-time monitoring of the operating conditions of various equipment in the substation.

[0071] Based on this, as Figure 4 shown in the flowchart of constructing the substation digital twin of a large-capacity skid-mounted substation provided, the key to constructing the substation digital twin is the construction of the digital twin model, which not only includes a single model describing the performance of the physical entity, but also includes an assembly model and a fusion model that comprehensively depict the physical entity from multiple angles and in all aspects. To ensure that the constructed digital twin model is more accurate and effective, a complete model framework needs to be constructed, mainly including model construction, model inspection, and model update, etc. Model construction mainly models the typical characteristics of the entity, including high-fidelity modeling, multi-physical field modeling, data-driven modeling, multi-structural 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 an output characteristic model under special working conditions, such as under the action of multi-physical fields. To move from a single model towards a digital twin, the single model is assembled in a hierarchical and orderly manner by adding appropriate constraint conditions in the spatial structure to construct an assembly model. Based on the coupling and correlation characteristics between the single model or the assembly model, multi-model and multi-physical field fusion is carried out to form a fusion model. All the constructed models are subjected to preliminary accuracy inspection and update by comparing with entity parameters. The assembled and fused models are combined in an orderly manner to construct an 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 inspection; if not, it is feedback updated through the physical entity parameters until a substation digital twin that meets the accuracy requirements is constructed.

[0072] And the construction of the substation digital twin depends on computing devices. The components of this computing device include but are not limited to a memory and a processor. The processor is connected to the memory through a bus, and the database is used to store data.

[0073] The computing device further includes an access device, which enables the computing device to communicate via one or more networks. Examples of these networks include the Public Switched Telephone Network (PSTN), Local Area Network (LAN), Wide Area Network (WAN), 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 wired or wireless network interface (e.g., Network Interface Card (NIC)), such as an IEEE802.11 Wireless Local Area Network (WLAN) wireless interface, Worldwide Interoperability for Microwave Access (Wi-MAX) interface, Ethernet interface, Universal Serial Bus (USB) interface, cellular network interface, Bluetooth interface, Near Field Communication (NFC) interface, and so on.

[0074] In one embodiment of the present application, other components not shown in the above components of the computing device may also be connected to each other, for example, via a bus, and those skilled in the art can add or replace other components as needed.

[0075] The computing device can be any type of stationary or mobile computing device, including mobile computers or mobile computing devices (e.g., tablet computers, personal digital assistants, laptop computers, notebook computers, netbooks, etc.), mobile phones (e.g., smartphones), wearable computing devices (e.g., smartwatches, smart glasses, etc.) or other types of mobile devices, or stationary computing devices such as desktop computers or PCs. The computing device can also be a mobile or stationary server.

[0076] Among them, the processor is used to execute computer-executable instructions for each step of constructing the substation digital twin. One embodiment of the present application also provides a computer-readable storage medium, which stores computer instructions that, when executed by the processor, are used to implement each step of constructing the substation digital twin. One embodiment of the present application also provides a chip, which stores a computer program that, when executed by the chip, implements each step of constructing the substation digital twin.

[0077] 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 recited in the claims may be performed in a different order than in the embodiments and still achieve the desired result. Additionally, the processes depicted in the figures do not necessarily require the specific order or sequential order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0078] The computer instructions include computer program code, which may be in the form of source code, object code, 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 media, USB flash drives, external hard drives, magnetic disks, optical discs, computer memories, read-only memories (ROMs), random access memories (RAMs), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium may be appropriately increased or decreased according to the requirements of legislation and patent practice within the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0079] It should be noted that for the foregoing method embodiments, for the sake of simplicity of description, they are all described as a series of action combinations. However, those skilled in the art should know that this application is not limited by the described action sequence, because according to this application, some steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0080] In the above embodiments, the descriptions of the respective embodiments have their own focuses. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0081] The preferred embodiments of the present application disclosed above are only used to help explain the present application. The optional embodiments do not elaborate on all the details, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this application. The present application selects and specifically describes these embodiments to better explain the principle and practical application of the present application, so that those skilled in the art can well understand and utilize the present application. 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 a shock-absorbing pad of preset size to reduce vibration and noise in a manner of half-laying and fitting the force-bearing 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; The large-capacity skid-mounted substation also includes a lightning protection device, wherein the lightning protection device includes a single lightning rod or a double lightning rod of unequal height, the single lightning rod is arranged on the truss column of the large-capacity transformer prefabricated cabin module, and the single lightning rod, on the highest point plane of the large-capacity skid-mounted substation, has a protection radius covering the farthest point of the large-capacity skid-mounted substation; the double lightning rod of unequal height includes 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, and 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.

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.

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