Electrical Substation
The electrical substation is the part of a power system in which the voltage is transformed from high to low or low to high for transmission, distribution, transformation and switching. The power transformer, circuit breaker, bus-bar, insulator, lightning arrester are the main components of an electrical substation.
Single Line Diagram of an Electrical Substation
The single line diagram of the substation is shown in the figure below. The connection of the substation is divided as
- Incoming or power feeder connection
- Outgoing feeder for feeding the other subsequent substations or switchgear.
- Power transformer connection.
- Voltage transformer connection for control and metering.
The circuit breaker is connected between the bus-bar and each incoming and outgoing circuit. The isolator is provided on each side of the circuit breaker. The current transformer is used for measurement and protection. The current transformers are placed on both sides of circuit breaker so that the protection zone are overlapped and cover the circuit breaker.
