Radial and Ring Distribution System

 Radial and Ring Distribution System

Radial and Ring Distribution system: In radial System, the primary feeders radiate from the distribution substations and branch in to subfeeders and laterals which extend in to all parts of the area served.

The system mainly used to serve light and medium density load areas i.e. , small towns and rural areas. The single line diagram of a radial distribution system.

From a feeder OC supplies a distributor AB at point A. Hence the distributor AB is fed at one end only from point A.

Advantages:

1.  Simple in construction

2.  Low investment cost

Disadvantages:

1. In this system every consumer is depend on a single feeder only. If any Fault occurs on the feeder causes every consumer will get affected from the power cut.

2. The end of the and distributor and nearest to the feeding point will be heavily loaded.

3.  In this system the end consumer will get affected from serious voltage fluctuations due to variation of load.

Ring Distribution System: Ring distribution system is a closed loop circuit starts from the substation bus-bars, makes a loop through the area to be served and returns to the sub-station.

The single line diagram of ring main distribution system. In this system the substation supplies to the closed feeder ABCDEFGHA. The distributors are tapped from different point B, D and F of feeder through distribution transformers.

Advantages:

1.   Lesser voltage fluctuations at consumer’s terminals.

2.   Reliability is more as compared to radial system.

3.   Repairs and maintenance is easy.

4.   Lesser voltage drop.

5.   Every consumer is supplied through two feeders.

Interconnected Distribution System : When the feeder ring is energized by two or more than two generating stations (or) sudstations it is called interconnected system. Fig. 6.5  shows the single line diagram of interconnected system.

Advantages:

1.  It increases the service stability

2.  Efficiency of the system is more

3. Any area fed from one generating station during speak load hours can be fed from the other generating station