油浸式电力变压器产品选用要点-佛山市禅星特变压器有限

Key Selection Points for Oil-immersed Power Transformers

Load Characteristics

When there is a large amount of Class I or Class II load, it is advisable to install two or more transformers. In the event that any one transformer is disconnected, the capacity of the remaining transformers shall be sufficient to supply power to the Class I and Class II loads. Class I and Class II loads should be centralized as much as possible and should not be overly dispersed.
When the capacity of seasonal load is relatively large, a dedicated transformer should be installed. Examples include air-conditioning chiller loads and heating electric loads in large civil buildings.
When the centralized load is large, a dedicated transformer should be installed. Examples include large heating equipment, large X-ray machines, and electric arc furnaces.
When the lighting load is large, or when the shared use of a single transformer for both power and lighting severely affects lighting quality and bulb lifespan, a dedicated lighting transformer may be installed. Under normal circumstances, a single transformer can be shared for both power and lighting purposes.

Operating Environment

Under normal medium conditions, either oil-immersed transformers or dry-type transformers can be selected, such as those used in independent or attached substations of industrial and mining enterprises, agricultural facilities, and residential district independent substations. Available transformer models include S8, S9, S10, SC(B)9, SC(B)10, etc.

Electrical Load

The capacity of a distribution transformer shall be determined by calculating the computed load based on the installed capacity of various electrical equipment (fire-fighting loads are generally not included). The apparent capacity after compensation shall serve as the basis for selecting the transformer capacity and the number of transformers. The load rate of a typical transformer is around 85%. This method is relatively simple and can be used for capacity estimation.
In GB/T17468-1998 Guidelines for the Selection of Power Transformers, it is recommended that the capacity of distribution transformers should be determined in accordance with GB/T15164-94 Loading Guide for Oil-immersed Power Transformers or GB/T17211-1998 Loading Guide for Dry-type Power Transformers, as well as the computed load. The two aforementioned guidelines provide computer programs and normal cyclic load diagrams for determining the capacity of distribution transformers.