Pagbuhat ug Paggamit sa Miniaturized Intelligent Prefabricated Substation
Sumala sa pagbutang sa mga smart city, ang urbano nga distribusyon network mahimong mag-ugmad ug ma-renovate, ug ang pagtukod sa mga proyekto sa undergrounding sa overhead line usab nagpadayon sa maayo. Daghang 10 kV overhead lines nahimong mas palitan ngadto sa underground cables. Konsiderando ang kasinatian sama sa limitado nga espasyo sa daghang urban nga mga karsada ug ang kahibaw-an sa mga lugar sa pag-install sa mga equipment, mas taas nga mga pangutana gihatag sa volume, structure, ug performance sa tradisyonal nga prefabricated substations.
Batasan sa aplikasyon sa tradisyonal nga prefabricated substations, ang makalaum nga article nagbuhat og pananaliksik ug analisis ug gidisenyo ang usa ka miniaturized, intelligent, ug landscaped prefabricated substation. Ang prefabricated substation naa may kompakto nga structure, stable nga performance, matigas nga praktikalidad, ug mataas nga reliability sa power supply. Kini makapahimo og intensive nga paggamit sa core urban space, makamit ang harmony ug unity sa palibot nga environment, ug mahimong makita sa maluwas ug renovation projects sa urban distribution networks.
1 Design sa Appearance sa Miniaturized Intelligent Prefabricated Substation
Konsiderando ang mga pangutana sama sa geographical location, space utilization rate, ug environmental limitations, ang miniaturized intelligent prefabricated substation gigamit ang usa ka long and narrow layout. Ang volume niini mao ra ang two-thirds sa original nga prefabricated substation. Ang casing (kasama ang top, doors, bottom, ug internal metal components) ug iyang attachments tanang gihimo sa 304 stainless steel, habang ang interior gihimo sa SGCC hot-dip galvanized thin steel plates, ug ang heat-insulating ug flame-retardant materials gi-add sa surrounding walls. Ang outer surface gi-paint sa dark green, na maayong pleasing ug environmentally friendly.
Ang casing adunay sufficient nga mechanical strength ug seismic performance aron sigurado nga dili easy to damage o deform sa panahon sa transport, installation, ug hoisting. Ang top sa casing gigamit ang "herringbone" structure nga may slope nga 5°. Kini double-layer structure nga may effect sa pag-isolate sa sunlight radiation. Igi-quip ania ang anti-backflow eaves ug ventilation duct, ug ang top sa casing detachable. Ang doors sa casing adunay double-layer anti-theft bolt structure ug open outward. Ang bottom sa casing hot-dip galvanized ug seamlessly connected sa casing body. May manhole sa bottom, ug sealing strips gi-install sa palibot sa manhole. Flammability-resistant cable sealing devices gi-provide sa duha ka gilid, na may good sealing ug complete moisture-proof measures.
Tanang welding parts ug joints sa external components sa miniaturized intelligent prefabricated substation well sealed, ug adunay characteristics sama sa water resistance, dust resistance, corrosion resistance, ug protection against ultraviolet radiation. Kini maayong pleasing ug environmentally friendly. Wala gyud kini nanginahanglan og maintenance, ang normal nga service life mahimong maabot sa 40 years.
2 Structure ug Layout Functions sa Miniaturized Intelligent Prefabricated Substation
2.1 Structural Layout Design
Ang structure sa miniaturized intelligent prefabricated substation simple. Ang interior sa casing divided into six main functional rooms: ang transformer room, high-voltage room, low-voltage room, automation room, communication room, ug power consumption collection room. Kini nga functional rooms completely separated from each other ug arranged in an "eye" shape.
Kini nga substation mahimong maghatag og pultahan sa apat ka gilid, na meet the maintenance requirements of opening doors sa tulo ka gilid. Ang protective doors sa high-voltage room ug low-voltage room equipped with mechanical interlocks aron sigurado nga ang high-voltage room door mahimong buksan lang kon ang low-voltage room door open. Tanang functional room adopts an independent natural ventilation method aron meet the requirements sa all electrical equipment for temperature ug humidity. Kon necessary, mahimong gi-add ang heaters, dehumidifiers, ug uban pa nga equipment aron ensure its safe ug reliable operation outdoors.
Ang main components sa substation include: oil-immersed transformers, 10 kV ring main unit low-voltage plastic shell air switches (sa low-voltage side) sealed with SF6 gas, standardized emergency power supply quick interfaces (sa low-voltage busbar side), as well as station terminal units, general meters, concentrators, intelligent configuration terminals, optical fiber communication terminals, etc.
2.2 Design sa Functional Rooms
(1) Transformer Room. Ang transformer room includes transformers, radiators, busbar wiring, ug safety protection nets, etc. Ang transformer uses a first-level energy efficiency fully sealed silicon steel sheet or amorphous alloy oil-immersed distribution transformer. Ang high-voltage side equipped with prefabricated pluggable cable heads, ug ang low-voltage bushings equipped with insulation protection sleeves. Ang capacity mahimong selected as 500 kV·A or 630 kV·A.
(2) High-Voltage Room. Ang high-voltage room composed of 10 kV ring main units, na divided into incoming line ug outgoing line unit cabinets, ug ang duha independent enclosed. Ang ring main unit is of a fully insulated ug common box structure, using SF6 gas for arc extinguishing ug insulation. Ang gas box equipped with a gas pressure display device with a normally open alarm auxiliary node. Ang gas box ug cabinet body made of 304 stainless steel ug high-quality aluminum-clad zinc plate materials respectively, ug ang surface sa cabinet body adopts an electrostatic epoxy spraying process.
Ang unit cabinet divided into a secondary room, a load switch room, ug a cable room from top to bottom. Ang secondary compartment located at the upper part of the unit cabinet. Ang panel sa compartment equipped with on-off switches, on-off indicator lights, remote/local transfer switches, as well as fault ug live indicators, etc. Ang load switch unit sa unit cabinet generally selects a combined electrical appliance of a load switch ug a current-limiting fuse. Among them, ang load switch can break the specified load current ug the transfer current when a fault occurs sa low-voltage side of the transformer; ang current-limiting fuse can cut off various phase-to-phase, grounding short-circuit currents, ug overload currents.
Ang load switch can achieve opening, closing, ug grounding through electric ug manual operations, ug ang operation simple ug convenient. Ang load switch unit ug grounding switch unit have a reliable "five-prevention" interlocking function. Ang cable room sa unit cabinet mainly uses the high-voltage cable trench for incoming ug outgoing lines from underground. Ang positions sa incoming ug outgoing cable terminals convenient for installation, ug ang open-type high-voltage current transformer installed.
(3) Low-Voltage Room. Ang low-voltage room mainly composed of low-voltage switchgear, emergency power supply compartments, ug manholes, etc. Ang color sa low-voltage cabinet body same as that of the high-voltage cabinet, using RAL7035. Ang pluggable digital multi-functional meter installed on the panel sa low-voltage cabinet, which can display voltage ug current ug supports RS-485 communication. Ang low-voltage outgoing lines use 4-circuit zero-flying-arc plastic shell air switches. Ang low-voltage side provided with a neutral line ug a ground line, both arranged at the bottom sa low-voltage cabinet.
Ang low-voltage busbar sa transformer introduced into the low-voltage switchgear from the emergency power supply compartment, designed to be detachable. After wiring conversion, it becomes a low-voltage feeder to the outgoing cable at the bottom sa low-voltage cabinet. Ang number of output circuits can be flexibly designed according to requirements. Ang emergency power supply compartment should be accompanied by operation instructions, ug ang manhole convenient for manual maintenance.
(4) Automation Room. Ang prefabricated substation equipped with an independent automation room, in which the distribution automation terminal (DTU) monitors ug controls the operating conditions of the 10 kV incoming ug outgoing line circuits, achieving functions such as remote measurement, remote signaling, remote control, ug remote adjustment. Ang DTU preferentially uses mains power for power supply. When there are no conditions for mains power supply, it uses a potential transformer for power supply ug uses a supporting storage battery as a backup power source.
It has a built-in power management module, which can meet the output of AC220V ug DC24V ug provides an AC220V alternating current power source for the electric operation mechanism of the ring main unit.Ang DTU supports multiple communication methods ug communication protocols, ug has 2 RS-485 serial interfaces ug 2 network interfaces (RJ45), which are compatible with protocols such as IEC101, IEC104, ug CDT; ang DTU installed as a whole in a wall-mounted cabinet, using an aviation plug, which convenient for on-site disassembly, installation, ug maintenance, ug can meet the space layout requirements of a set of terminals ug backup power sources.
(5) Communication Room. Ang prefabricated substation equipped with an independent communication room, which internally configured with an optical distribution frame, an industrial Ethernet switch, ug an optical network unit, ug reserves the wiring slots ug incoming ug outgoing holes for communication optical cables, pigtails, ug power cables. This room can transmit the monitoring data inside the prefabricated substation to the intelligent monitoring platform, so as to monitor its operating status ug data in real time.
(6) Power Consumption Collection Room. Ang power consumption collection room located above the communication room. It equipped with installation positions for intelligent distribution transformer terminals, concentrators, ug general meters of the transformer area, as well as installation spaces for terminal blocks ug combined wiring test boxes, ug reserves the wiring slots ug incoming ug outgoing holes for sampling signals ug communication cables.
This room responsible for measuring various operating parameters of the prefabricated substation ug is the communication hub of electric energy data. On the one hand, it collects ug stores the electric energy data output in the form of serial communication by digital electric energy meters. On the other hand, it transmits the collected electric energy data to the upper computer of the main station of the electric energy billing automation system through the upstream channel.
2.3 Design sa Grounding Device
Ang grounding electrode sa miniaturized intelligent prefabricated substation uses a galvanized iron pipe. Ang grounding busbar sa channel steel base provided with 2 copper grounding terminals connected to the grounding electrode, with an electrical contact cross-sectional area of 160 mm² ug obvious signs. Ang low-voltage neutral line sa transformer directly connected to the grounding body. Among them, ang transformer room, high-voltage room, ug low-voltage room connected to each other using grounding terminals.
Ang secondary safety grounding wires sa electrical equipment added with transparent protective sleeves, ug ang copper wires have a cross-sectional area of 4 mm²; all cabinet doors, metal parts, ug metal frames continuously ug reliably connected to the ground. Ang external grounding grid sa foundation introduced into the bottom sa prefabricated substation from the inner side sa foundation ug connected to the grounding terminals in the station, using a direct burial method. Ang grounding resistance sa prefabricated substation not greater than 1 Ω.
3 Technical Requirements sa Miniaturized Intelligent Prefabricated Substation
3.1 Electrical Principle
Ang miniaturized intelligent prefabricated substation suitable for the distribution network of a 10/0.4 kV three-phase AC system. It integrates high-voltage switchgear, distribution transformers, ug low-voltage distribution devices according to a specific wiring scheme. Ang high-voltage side adopts a single busbar wiring, with two incoming lines ug one outgoing line. A fuse protection set on the transformer side. After being transformed by the distribution transformer, ang low-voltage busbar can be designed with 4 low-voltage feeder lines according to needs, ug no low-voltage main switch set.
3.2 Applicable Places
Kini nga miniaturized intelligent prefabricated substation widely applicable to outdoor places such as urban distribution network renovation, residential communities, factories ug enterprises, commercial office buildings, business districts, public green areas, cultural protection areas, ug parks.
3.3 Environmental Conditions for Use
Altitude: not exceeding 1,000 m.
Ambient temperature: ang pinakamababa -25 °C, ang pinakamataas 45 °C; ang pinakamataas annual average temperature does not exceed 20 °C, ug ang pinakamataas monthly average temperature does not exceed 35 °C.
Relative humidity: sa 20 °C, ang pinakamataas monthly average does not exceed 90%, ug ang pinakamataas daily average does not exceed 95%.
Seismic resistance: ang ground horizontal acceleration does not exceed 0.2 g (g represents the acceleration due to gravity), ug ang ground vertical acceleration 0.1 g.
Sunshine intensity: when the wind speed 0.5 m·s⁻¹, ang solar radiation intensity does not exceed 0.1 W·cm⁻².
Maximum ice coating thickness: 10 mm.
Pollution level: not exceeding level III
Ground inclination: not greater than 3°.
Installation location: outdoor, without explosion hazards, fires, chemical corrosion, or severe vibrations.
If it does not conform to the above normal environmental conditions for use, it needs to be negotiated ug resolved between the user ug the manufacturer.
4 Prototype Acceptance sa Miniaturized Intelligent Prefabricated Substation
Ang miniaturized intelligent prefabricated substation was prototyped by Jiangsu Qihou Intelligent Electrical Equipment Co., Ltd. Ang Quality Inspection Center for High-Voltage Transmission ug Distribution Equipment of the Machinery Industry conducted tests on the main components according to relevant national standards ug industry standards, ug ang test results qualified. Ang State Grid Shanghai Electric Power Company conducted a comprehensive acceptance of the size, appearance, ug performance of this prototype, ug ang acceptance results qualified.
5 Conclusion
Ang miniaturized intelligent prefabricated substation developed in this article integrates the advantages of existing prefabricated substations at home ug abroad. It has the advantages of a simple structure, a small footprint, safety ug reliability, beauty ug environmental protection, exemption from inspection ug maintenance, ug low maintenance requirements. It has important promotional ug application value in the construction ug renovation of urban distribution networks.
