Mobile substations are used at points where there is an urgent need for energy. Mobile transformer stations can be easily assembled into transportation equipment such as trailers, trailers, containers, platforms. The location to be established during the construction of the transformer centers depends on criteria such as the need for resources and the anticipated change in the short and long term. Mobile substations provide power supply in areas where energy needs are urgent, such as military bases, industrial and commercial facilities, and city networks, due to their portability and quick and easy commissioning. In addition, the energy requirement of the newly established facility can be used ready for commissioning in the field against power cuts. Mobile substations play an important role in sudden interventions. A label showing the connection scheme should be placed on the mobile substations. It explains all the details in the connection diagram of this study. The purpose of this connection diagram is to prevent dangers that may occur during installation in emergency situations. Mobile substation manufacturing may vary depending on the power of the transformer center, the terrain conditions, the type of transportation and the auxiliary materials desired in the substation. Generally, in a center, there are air insulated cells or gas insulated cells, metal cladders, LV distribution and control panels, battery battery group, transformer - cell connections and cables for field connections, reel systems where the cables are wrapped and an internal need transformer. All the connections of these products in the mobile substation are available on the vehicle with the connections made. It can be used directly by making field connections in line with the needs. The transformer is the mobile station’s largest, heaviest and most expensive equipment. The basic criteria in the design of a mobile transformer are to keep all the necessary parameters of the transformer within a certain limit, but also to make efforts and increase its compactness to reduce its size, weight and cost. Transformer design must be optimized in terms of size and weight for portability and required electrical parameters.