From a literal perspective, a box-type substation is a complete substation designed in an enclosed structure, while a box-type transformer is simply a transformer housed within an enclosure. The distinction becomes clear when their functions are separated: one is a substation, and the other is a transformer.

The differences can be explained from the following aspects:

Differences in Structure:
A box-type substation typically consists of a transformer, disconnect switch, capacitor bank, distribution cabinet, AC distribution system, DC power supply, control system, and other integrated components, all housed within a single enclosure.
A box-type transformer, on the other hand, is an enclosed unit containing transformer components only, available in either vertical or horizontal configurations. Its structure is much simpler than that of a box-type substation.

Differences in Function:
A box-type substation is primarily used for voltage transformation, power distribution, and electrical network management. It is widely applied in industrial enterprises, urban power grids, railway systems, petroleum facilities, chemical plants, and other industries. It can transmit high-voltage electricity to designated locations and convert it into usable electrical power.
A box-type transformer is a dedicated voltage conversion device designed specifically to step voltage up or down, converting high voltage to low voltage or vice versa.

Differences in Application:
Box-type substations are suitable for a wide range of applications, including industrial parks, petrochemical plants, urban distribution networks, and railway systems. Their use can improve power system efficiency, reduce power supply interruptions, and enhance the overall reliability and stability of electrical networks.
Box-type transformers are typically used as components within power systems, such as substation distribution systems, transmission lines, and power generation facilities.