1. American box transformer:

1) Wiring form of box transformer: one or two 10KV incoming lines; The capacity of a single transformer is generally 500KVA~800KVA; 4~6 low-voltage outgoing cables.

2) The main components of the box transformer are transformer, 10KV ring network switch, 10KV cable plug, low-voltage pile head box and other main components. It has the advantages of small size, low cost and easy installation. Advantages and disadvantages of American box transformer

3) Advantages: small size, small floor area, easy placement, easy camouflage, easy to coordinate with the environment of the community. It can shorten the length of low-voltage cable, reduce line loss, and also reduce the cost of power supply.

4) Disadvantages: low power supply reliability; Without electric mechanism, it is impossible to add distribution automation device; No capacitor device is unfavorable for reducing line loss; The noise is higher than that of Type III and V stations, because Type III and V stations place transformers indoors to provide sound insulation; In addition, the concentrated electromagnetic radiation of Type III and V stations is decomposed into multipoint radiation; Due to the different civil foundation of box transformer with different capacity, the capacity expansion of box transformer is inconvenient; When the box transformer is overloaded or the capacity of the user is increased, the civil engineering needs to be rebuilt, which will have a long power outage time and increase the difficulty of the project.

2. European box transformer:

1) Wiring form of box transformer

A. Single distribution transformer form - two 10KV incoming lines; The capacity of a single transformer is generally 500KVA~800KVA; Low-voltage outgoing cables are generally 4~6 routes.

B. Two distribution transformers - two 10KV incoming lines; Two transformers, each with a capacity of 500KVA~800KVA; Low-voltage outgoing cables are generally 8-12 channels.

2) The main components of the box-type substation are transformer, 10KV ring-network switch cabinet, low-voltage capacitor, low-voltage switch and other main components, which is equivalent to compact installation of the equipment of the type III station in the metal box, so as to miniaturize the type III station. The volume and cost of European box transformer are higher and larger than those of American box transformer.

3) Advantages: the noise is equivalent to that of Type III station and Type I station; The radiation is lower than that of American box-type transformer, because the transformer of European box-type transformer is placed in a metal box to play the role of shielding; Distribution automation can be set up, which not only has the advantages of Type III and Type I stations, but also has the main advantages of American box-type substation.

4) Disadvantages: The large volume is not conducive to installation and has a certain impact on the environmental layout of the community;

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Due to the different structure of the box transformer, the place of use is also different, and the power supply network is also different

Because the structure and reliability of American and European box transformers are different, the applicable occasions are also different. When the capacity of American-style box transformer is small and the building area of the residential area is large, the applied box transformer will increase a lot, thus increasing the load points connected on the overhead line; When reducing the supporting load points of overhead line, it is necessary to increase the number of series connection of box transformer, thus weakening the network structure. To overcome the problem of weak network structure caused by small-capacity box change, it is better to use ring website.

Applicable place of American box transformer

In view of the structural characteristics, advantages and disadvantages of American box transformer, American box transformer is applicable to the power consumption of multi-storey residential buildings and other unimportant buildings with relatively low power supply requirements. According to our actual use, the American box-type substation is fully suitable for the power supply demand of multi-storey residential buildings after it is equipped with a small ring network switch station. Because it is the box transformer that breaks down, it has little impact on residents, but it is not suitable for small high-rise and high-rise buildings.

Applicable place of European box transformer

European box transformer is applicable to multi-storey residential buildings, small high-rise buildings, high-rise buildings and other important buildings.