Description of Station Transformer

The Station Transformer (referred to as "station transformer" for short) is a specialized transformer responsible for providing on-site power supply in power hubs such as substations and power plants. Its core function is to step down the high-voltage electricity from the power grid (e.g., 110kV, 220kV, 500kV) to low voltage (380V/220V) to supply power to auxiliary facilities in the station, including control circuits, lighting systems, cooling equipment, communication devices, and pump machinery. As the "internal energy hub" of power facilities, it does not directly participate in external power transmission but maintains the stable operation of core links such as monitoring, protection, and operation and maintenance of the entire power station. It is a key device ensuring the safe and reliable operation of power hubs.

• 3-Ph 66MVA/22kV, Dyn1-yn1, ONAN/ONAF

• Supply station transformer for all the type of power plant, the range covers from S-50kVA/6kV to SFFZ-40000kVA/66kV.

Features of Station Transformer

• High-reliability design: Adopts redundant configuration (e.g., "one main and one standby") and supports seamless switching to avoid power loss in the station due to a single unit failure. Core components are made of anti-aging materials to ensure long-term continuous operation (annual operating time usually exceeds 8000 hours).

• Flexible adaptability: The primary side voltage matches the high-voltage level of the local power grid (10kV–500kV), and the secondary side outputs standard low voltage of 380V/220V. The winding structure can be adjusted according to the type of on-site load (inductive, capacitive) to meet the power demand of power equipment such as water pumps and fans, as well as precision control instruments.

• Miniaturization and integration: The capacity is usually 50kVA–40000kVA (much smaller than the main transformer), with a compact structure. It can be installed in indoor switch cabinets or outdoor box-type enclosures to save space in the station. Some dry-type station transformers use epoxy resin casting, without oil conservators, adapting to narrow environments.

• Comprehensive protection mechanism: Equipped with built-in overcurrent, overvoltage, zero-sequence protection, and temperature monitoring devices. Oil-immersed station transformers are fitted with gas relays, and dry-type station transformers have high-temperature alarm functions, which can quickly respond to faults such as short circuits and overloads to protect themselves and downstream loads.

• Dual focus on energy efficiency and environmental protection: Complies with the latest energy efficiency standards (e.g., GB 20052). Uses low-loss silicon steel sheets and optimized winding design, reducing no-load loss by more than 15% compared with traditional models. The oil-free design of dry-type station transformers avoids oil leakage pollution, making them suitable for power stations in ecologically sensitive areas.