A. Classification of box-type transformers

　　Box-type transformer is divided into European style (European style) and American style (American style), American style volume (Volume0) small, load capacity is low, power supply reliability is not high, European style volume is larger, load capacity and power supply reliability are stronger than the American style, in our country is generally used in the European style box transformer.

　　Combined transformer (commonly known as American box transformer is also called box-type transformer) is the transformer, high-voltage receiving part of the load switch and protection device, low-voltage distribution device, low-voltage metering system and reactive power compensation device combined together in a complete set of transformer and distribution equipment.

　　Combined transformers (commonly known as American box transformers)

　　The main features of the combined transformer (commonly known as American box transformer) are: fully sealed, fully insulated, compact structure, beautiful appearance, and the volume is only about 1/3 of that of the box-type substation (European box transformer). No need for distribution room, can be placed directly in the indoor or outdoor, can also be placed in the street and green belt, reliable to ensure personal safety, both power supply facilities, but also can decorate the environment.

　　Combined transformer (commonly known as American box transformer is also called box transformer) can be used for terminal power supply and ring network power supply, conversion is very convenient, to ensure the reliability of power supply, flexibility. The use of double fuse full range protection method, stable Bo transformer greatly reduces the operating cost.

　　The 10kV casing cable head can be plugged and unplugged many times under 200A load current, used as a load switch in emergencies, and has the characteristics of an isolation switch. Combined transformer (commonly known as American box transformer also called box transformer) using domestic 9, 11 type distribution transformer, low loss, low noise, long service life.

　　Second, the main characteristics of box-type transformers

　　Box-type substation is mainly composed of multi-loop high-voltage switching system, armored busbar, substation integrated automation system, communication, remote, metering, capacitance compensation and DC power supply and other electrical units combined, installed in a moisture-proof, rust-proof, dust-proof, rodent-proof, fire-proof, anti-theft, heat insulation, fully enclosed, movable steel structure box, electromechanical integration, fully enclosed operation, mainly has the following characteristics:

　　1) Advanced technology and safety

　　The box part adopts the current leading technology and process, the shell is generally made of aluminized zinc steel plate, the frame adopts standard container material and production process, with good anti-corrosion performance, to ensure 20 years without rusting, the inner sealing plate adopts aluminum alloy buckle plate, the sandwich layer adopts fireproof insulation material, the box body is installed with air conditioning and dehumidification device, the operation of the equipment is not affected by the natural climate environment and external pollution, can ensure normal operation in -40℃ ~ +40 40℃ under the harsh environment of normal operation.

　　The primary equipment inside the box adopts fully enclosed high-voltage switchgear (such as: XGN type), dry transformer, dry transformer, vacuum circuit breaker, spring-operated mechanism, rotary isolation switch and other leading domestic technology equipment, the product has no exposed live parts, is fully enclosed, fully insulated structure, can completely achieve zero electric shock accident, the whole station can realize oil-free operation, high security, the secondary adopts microcomputer integrated automation system, can The secondary adopts a microcomputer integrated automation system, which can realize unattended operation.

　　2) High degree of automation

　　The whole station is intelligently designed, the protection system adopts the substation microcomputer integrated automation device, which is decentralized and can realize "four remote", i.e. telemetry, telecommunication, remote control and remote regulation, each unit has independent operation function, the relay protection function is complete, the operating parameters can be set remotely, the humidity and temperature inside the box can be controlled and the smoke alarm can be remote, which meets the requirements of unmanned duty; according to the needs, the image Remote monitoring.

　　3) Factory prefabrication

　　Design, as long as the designer according to the actual requirements of the substation, to make a main wiring diagram and the design of equipment outside the box, you can choose by the manufacturer to provide the specifications and models of the box, all equipment in the factory once installed, commissioning qualified, the real realization of substation construction factory, shorten the design and manufacturing cycle; on-site installation only box positioning, cable contact between boxes, outgoing cable connection, protection of the value of the calibration, and Transmission test and other commissioning work, the whole substation from installation to operation only need about 5 ~ 8 days of time, greatly shortened the construction period.

　　4) Flexible combination

　　Box-type substation due to the compact structure, each box constitute an independent system, which makes the combination of flexible and variable, on the one hand, can be all box-type, that is, 35kV and 10kV equipment all box installation, the composition of the full box-type substation; can also only use 10kV switch box, 35kV equipment outdoor installation, 10kV equipment and control system box installation, for this combination of For this combination, it is particularly suitable for the transformation of old stations in the transformation of agricultural networks, i.e. the original 35kV equipment is not moved, only a 10kV switch box can be installed to achieve the requirements of unattended. In short, the box-type substation does not have a fixed combination mode, the use of units can be freely combined according to the actual situation of some models to meet the needs of safe operation.

　　5) Save investment and quick results

　　Box-type substation than the same size of conventional substation to reduce investment 40% to 50%, to 35kV single main variable 4000kVA scale substation, civil engineering (including land acquisition costs) box-type substation than conventional substation to save more than 1 million yuan; if the analysis from the completion of the production point of view, a conservative estimate of each station in advance of 4 months in operation, if the average load of 2000kW, the sale of electricity profit 0.10 Yuan/kW.h, three months can increase the net profit of more than 600,000 yuan; analysis from the operating point of view, in the box-type substation, due to the choice of advanced equipment, especially oil-free equipment operation, fundamentally solve the problem of leakage of equipment in conventional substations, substations can implement state maintenance, reduce maintenance workload, can save about 100,000 yuan per year operation and maintenance costs, the overall economic benefits are very considerable.

　　6) Small footprint

　　To 4000kVA single main transformer scale substation, for example, the construction of a conventional 35kV substation, about 3000m2, and the need for large-scale civil engineering; and the choice of box-type substation, the main transformer box and switch box two box body covers an area of up to 100m2, including 35kV other equipment covers a total area of 300m2, only for the same scale substation covers an area of 1/ 10, can make full use of the street, square and factory corner can be installed and put into operation, in line with the national land-saving policy.

　　7) Beautiful appearance, easy to coordinate with the environment

　　The box shell adopts aluminous zinc-plated steel plate and container manufacturing technology, with a beautiful design, and it is easy to harmonise with the surrounding environment by choosing the colour of the shell of the box-type substation under the premise of ensuring the reliability of power supply. Mobile substation, with the role of embellishment and beautification of the environment.

　　Electricity knowledge of box-type transformer several classification and characteristics

　　A, the classification of box-type transformers

　　Box-type transformer is divided into European style (European style) and American style (American style), American style volume (Volume0) small, load capacity is low, power supply reliability is not high, European style volume is larger, load capacity and power supply reliability are stronger than the American style, in our country is generally used in the European style box transformer.

　　Combined transformer (commonly known as American box transformer is also called box-type transformer) is the transformer, high-voltage receiving part of the load switch and protection device, low-voltage distribution device, low-voltage metering system and reactive power compensation device combined together in a complete set of transformer and distribution equipment.

　　Combined transformers (commonly known as American box transformers)

　　The main features of the combined transformer (commonly known as American box transformer) are: fully sealed, fully insulated, compact structure, beautiful appearance, and the volume is only about 1/3 of that of the box-type substation (European box transformer). No need for distribution room, can be placed directly in the indoor or outdoor, can also be placed in the street and green belt, reliable to ensure personal safety, both power supply facilities, but also can decorate the environment.

　　Combined transformer (commonly known as American box transformer is also called box transformer) can be used for terminal power supply and ring network power supply, conversion is very convenient, to ensure the reliability of power supply, flexibility. The use of double fuse full range protection method, stable Bo transformer greatly reduces the operating cost.

　　The 10kV casing cable head can be plugged and unplugged many times under 200A load current, used as a load switch in emergencies, and has the characteristics of an isolation switch. Combined transformer (commonly known as American box transformer also called box transformer) using domestic 9, 11 type distribution transformer, low loss, low noise, long service life.