What are Transformer Substations? Basic Information about Concrete Substations, Prefabricated and Metal Structures.
Transformer substations, which ensure the safe and controlled distribution of electrical energy in the field, consist of medium-voltage switchgear, transformers, low-voltage panels, power cables, and various auxiliary equipment. Special enclosure structures are used to protect all these systems from environmental influences. These structures are generally referred to as transformer kiosks in the industry.
Located in residential areas, industrial zones, or energy infrastructure projects, these structures can be designed in the form of concrete kiosks, prefabricated kiosks, or metal kiosks. The interior layout is shaped according to the needs of the transformer substation. Medium-voltage switchgear, transformers, and low-voltage panels are usually placed in separate rooms. This separation is important for both safety and ease of maintenance. The contents of these structures can be expanded or simplified according to the usage scenario.
Concrete Pavilion Usage and Structural Characteristics
Concrete substations are among the most preferred enclosure structures for medium and low voltage systems. These substations, with their reinforced concrete exterior, are often produced as monoblock, meaning they are made of a single piece. Because the foundation and side walls are poured together, they offer advantages in terms of both structural integrity and watertightness. The substation’s floor has passages suitable for underground cable connections. This allows medium and low voltage cables to be brought directly into the substation from underneath.
The ceiling area can be designed to relieve sudden gas pressure, especially in the event of internal arc faults. The concrete exterior surfaces are reinforced with external cladding to provide resistance to weather conditions. The roof structure is also designed to prevent rain or snow leakage. Doors are generally made of galvanized sheet metal and are mounted to offer a wide opening.
Concrete substations produced in Turkey must be manufactured in accordance with the TEDAŞ MYD/2000-036.C technical specification. This standard; It covers many critical topics such as safety, structural integrity, ventilation, insulation, and interior design.
Concrete Pavilion Dimensions and Usage Limits
The dimensions of concrete substations depend on the transformer’s power and the characteristics of the installation area. This type of substation is mostly preferred in systems of 400 kVA and above. However, due to production limitations, concrete substations can generally only be manufactured up to a maximum of 7.2 meters. If a transformer building larger than this is required, prefabricated or metal substation solutions can be considered as alternatives.
Prefabricated Transformer Substations
Prefabricated substations are preferred in large projects due to their ease of assembly and flexible size options. Similar to concrete substations, they contain separate sections for MV and LV panels, as well as the transformer. However, these structures are delivered to the site in disassembled form and assembled on-site. Their exteriors can be painted in various colors and secured with mechanically lockable sections.
The standard applicable to prefabricated structures used in TEDAŞ (Turkish Electricity Distribution Company) projects is the TEDAŞ MLZ/2006-52.A specification. This document defines the technical, structural, and safety criteria for prefabricated transformer substations. With an IP23 protection class, these structures offer adequate protection against external environmental conditions.
Metal Pavilion Usage Areas and Features
Metal substation enclosures stand out from other solutions in terms of portability and lightness. Their bodies are made of hot-dip galvanized sheet metal, and their inner and outer surfaces are generally coated with electrostatic powder paint. In medium voltage (MV) projects, the RAL 7032 color code is commonly used, but custom color options are also available. The roof is designed with insulation to reduce heat transfer.
Metal substation enclosures can be used for transformers ranging from low-power transformers like 50 kVA to those up to 4000 kVA. They can integrate not only transformers but also additional equipment such as MV switchboards, LV switchboards, battery-rectifier groups, or generators. They can be shipped fully assembled on site or empty.
Lighter than concrete substations, these structures can be easily transported to distant locations by road. Especially in international projects, mobile transformer substation solutions, transportable on trailers or semi-trailers, are created using metal substation kiosks. Although TEDAŞ (Turkish Electricity Distribution Company) does not have specific technical specifications for metal substations, these products are generally shaped according to project-specific technical requirements.
When planning a transformer substation, the type of kiosk to be used should be determined according to the system’s power, installation area, and environmental conditions. Options such as concrete kiosks, prefabricated kiosks, and metal kiosks each offer advantages for different needs. In choosing the right transformer substation, attention should be paid not only to power capacity but also to technical details such as the dimensions of the kiosk, the placement of internal equipment, the ventilation system, and maintenance access. A properly designed and project-specific transformer building ensures both safe energy distribution and contributes to the longevity of the system.