What is a Single Line Diagram?
A Single Line Diagram or a One Line Diagram is a simple way to draw the Electrical Circuit in a Power System. By adopting this Electrical Line Diagram the Complexity of the Pictorial Representation can be reduced.
A typical Electrical Single Line Diagram Consist of a
- Generator (Generating Station)
- Step Up Transformer
- Step Down Transformer
- The Power Generated from the Generating Station is step Up using the Step-Up Transformer and then the Primary Transmission Takes Place.
- Step-Up Transformer is used to Minimise the Transmission Loss.
- 11Kv is Step Up to 220Kv before sending to Primary Transmission.
- In other Words, Primary Transmission is also called High Voltage Transmission since it deals with very high Voltage.
- Primary Transmission uses 3 phase 3 Wire System (Over Head Transmission Lines)
- At the Receiving Station, the voltage level is step-down from 220Kv to 33KV using Step-Down Transformer.
- Second Transmission System uses 3 phase system to Transmit Power to the various Sub-stations.
- In the Primary Distribution, a step-Down transformer (Usually called as Distribution Transformer) is used to reduce the Voltage to the desired Level.
- The Voltage is Step down from 33KV or 22Kv to 6.6Kv or 3.3Kv.
- Large Factories and Industries get power from Primary Distribution. Companies using Primary Distribution have their own Sub-station.
- It is also called High-Voltage Distribution.
- In Secondary Distribution, a Step-down transformer is again used to reduce the voltage level from 3.3 Kv to 440V or 230v.
- The End consumers get power through Secondary Distribution.
- 230V is used for Domestic Purposes.
- It is also called Low Voltage Distribution.
- The Secondary Distribution uses 3 phases and 4 wire system (Neutral Wire)