Electrical substations, also known as transformers, are electromechanical installations designed to modify voltage levels in the electrical system. Their purpose is to enable the efficient transmission of electrical energy from generation centers to consumption points, adapting the voltage according to the process stage: generation, transmission, or distribution.
Main components
- Power transformers: increase or reduce the voltage depending on the function of the substation.
- Power switches: allow circuits to be opened or closed in a controlled manner, even under load.
- Disconnectors: switching devices for opening circuits without load.
- Protection relays: detect electrical faults and send trigger signals.
- Fuses and circuit breakers: protect against overcurrents and short circuits.
- Medium voltage cells: mainly used in transformation centers.
- Control, measurement and remote control systems.
Types of substations according to their function
- Forklifts: they convert the generated voltage (usually 11–30 kV) to higher voltages (132, 220 or 400 kV) for long-distance transportation.
- Reducers: reduce transport voltages (132–400 kV) to medium voltage levels (10–66 kV) for regional distribution.
- Transformation centers: they reduce the medium voltage to low voltage (400/230 V) for final consumption.
Railway electrical substations (ADIF case)
In the railway sector, substations have a critical function: supplying power to the overhead lines for the electric traction of trains. ADIF, as the railway infrastructure manager in Spain, operates substations that supply power to both high-speed and conventional lines.
General technical characteristics
- Input voltage: 220 kV or 400 kV from the transmission network Spanish Electricity Grid.
- Exit system: 2×25 kV single-phase (frequent in high speed) or 3 kV DC (conventional lines).
- Traction transformers: they convert the high input voltage to the levels required by the catenary.
- Rectifiers: used in direct current systems to convert alternating current to direct current.
- Auxiliary services: power supply for signalling systems, telecommunications, switch heating, tunnel lighting and ventilation.
Representative examples
- Traction substations such as Cañaveral or Zamora transform 400 kV or 220 kV into 2x25 kV to directly feed the catenary in high-speed lines.
- Railway distribution substations such as those in Valladolid or Palencia, supply auxiliary equipment, control centres or intermediate stations.
Metal and safety elements in substations
In InsametalWe design and manufacture metal solutions tailored to the demands of electrical substations. Our products, made primarily of galvanized steel or aluminum, are designed to withstand harsh environments, meet regulatory requirements, and ensure operational safety.
Railings and handrails
- Manufactured according to ADIF specifications.
- Designed for roofs, technical access and service stairs.
- Finishes in hot-dip galvanizing, powder coating or anti-corrosion duplex systems.
- Link: here
Perimeter enclosures
- Pre-sensorized systems
- Structures with electro-welded mesh and structural profiles.
- Access control through doors with mechanical or electronic locking systems.
- Link: here
Technical doors
- Made of steel, with or without thermal insulation.
- They incorporate ventilation grilles for heat dissipation in electrical rooms.
- Designed to ensure watertightness, safety and fire resistance if required.
- Link: here
