Components of a substation
Substations are critical nodes in electrical power distribution systems. They perform the vital function of stepping down high voltage electricity from transmission systems to lower voltages suitable for consumer use.
Here are the key components highlighted in the image, each playing a unique role in ensuring efficient and safe power distribution:
1. Surge Arrester (up to 500kV):
• Protects electrical equipment from over-voltage transients caused by external (lightning) or internal (switching) events.
2. Insulator (up to 500kV):
• Prevents unwanted flow of current to the earth from the power-carrying conductors, ensuring safety and reliability.
3. Gas-Insulated Switchgear (GIS, up to 275kV):
• Encloses electrical equipment in a sealed environment with sulfur hexafluoride gas, providing high reliability and compact size.
4. Dry-Type Transformer (up to 35kV):
• Used to reduce or increase voltage levels without the need for insulating oil, offering safety and maintenance advantages.
5. Medium Voltage & Low Voltage (MV & LV) Switchgear Panels:
• Distribute electrical power within the substation and to external circuits, ensuring controlled and safe distribution.
6. Power Transformer (up to 750kV):
• Steps down high transmission voltages to distribution voltages, or vice versa, essential for efficient power delivery over long distances.
7. Current Transformer (CT) & Potential Transformer (PT, up to 230kV):
• CTs reduce high currents to measurable values, while PTs reduce high voltages, aiding in protection, control, and metering of electrical systems.
8. Disconnector (up to 252kV):
• Ensures that a section of the circuit is completely de-energized for maintenance, ensuring safety for personnel.
9. Circuit Breaker (up to 252kV): • Automatically interrupts electrical flow in case of a fault, protecting the electrical circuit from damage caused by overcurrent or short circuit.
