Electrical Substation and its types

 ⭕ Electrical Substation and its types ⁉

🔸 An electrical substation is a key part of the power generation, transmission, and distribution system. It is a facility where electrical power is transformed from one voltage level to another, controlled, and distributed. Substations play a crucial role in ensuring the efficient and reliable delivery of electricity to end users. 

⭕ Importance of Substations:

✅ Efficiency: Minimize power losses during transmission by using higher voltages.

✅ Reliability: Ensure uninterrupted power supply by isolating faults.

✅ Scalability: Manage growing power demands with flexible designs.

⭕ Types Of Substations:

🔸 There are many kinds of ac substations. They are classified into different types based on various criteria. Some of them are discussed below.

⿡ Based on Construction and Installation:

➡ Air-Insulated Switchgear (AIS) Substation:

🔸 Equipment is installed in open air and uses atmospheric air for insulation.

🔸 Economical and widely used for high-voltage systems in rural or outdoor areas where space is not a constraint.

🔸 Requires regular maintenance due to exposure to environmental conditions like dust and moisture.

➡ Gas-Insulated Switchgear (GIS) Substation:

🔸 Encapsulated in sealed enclosures filled with SF₆ (sulfur hexafluoride) gas, which provides excellent insulation.

🔸 Compact design makes it ideal for urban areas or places with limited space.

🔸 Higher installation costs but low maintenance requirements and greater reliability.

⿢ Based on Transmission Voltage and Function:

➡ Transmission Substation:

🔸 Handles very high voltages (typically 110 kV to 765 kV).

🔸 Steps up voltage from generating stations for long-distance transmission, reducing power loss.

🔸 Also steps down voltage for regional or subtransmission systems.

🔸 Includes large transformers, circuit breakers, and protection systems.

➡ Subtransmission Substation:

🔸 Operates at intermediate voltage levels (33 kV to 110 kV).

🔸 Transfers power from transmission substations to distribution substations.

🔸 Typically used in smaller towns or industrial areas.

➡ Distribution Substation:

🔸 Steps down voltage to usable levels (11 kV or lower) for end users.

🔸 Supplies power to residential, commercial, and industrial areas.

🔸 Located near load centers and often uses compact switchgear to save space.

⿣ Based on Installation Premises:

➡ Generating Substation:

🔸 Located near power plants.

🔸 Steps up voltage for transmission to the grid.

➡ Customer Substation:

🔸 Supplies power directly to large consumers, like factories or industries.

🔸 Customized for specific needs.

➡ System Station:

🔸 Acts as a control hub for managing power flow across the grid.

🔸 Ensures system stability and reliability.

➡ Switching Substation:

🔸 Facilitates the switching of transmission lines.

🔸 Does not change voltage but provides isolation and system control.