Radial Distribution

[Guinevere]

Dear All,
i'm a new engineer, reviewing technical specification on switchgear(main breaker), and found this term "Distribution : Radial" requirement in Incoming Power Supply, what does it mean anyway?
Thanks before for your answer

 

[Zogzog]

The primary design features of a simple radial system include a single incoming feed, through switching and protection devices, to a step down transformer. On the secondary side of the transformer, usually, a circuit breaker feeds a bus system with feeder breakers radiating out to the various loads.

The advantages of the radial system are limited cost and adequate protection. The disadvantage is very limited flexibility. The most common substation configurations are simply modifications of this basic design to add flexibility and redundancy to the system.

 

[7anoter4]

"Electricity distribution networks are typically of two types, radial or interconnected. A radial network leaves the station and passes through the network area with no connection to any other supply. This is typical of long rural lines with isolated load areas. In general, the radial distribution network has more power failures than the interconnected distribution networks.
The interconnected network has multiple connections to the points of supply.
The network is the most sophisticated type of distribution system. It does not employ a radial power flow concept but instead relies on the fact that each load receives its power from several parallel paths operating simultaneously. This is achieved by using a grid of interconnected primary or secondary lines to serve the loads connected to it. For radial systems, the term connecting to the “grid” is used loosely and is really a misnomer given the “fanned” nature of radial power flows on radial systems." see:

http://mydocs.epri.com/docs/public/000000000001012922.pdf

 

[waross]

Radial distinguishes the system from loop or grid systems. Note that the term "Grid" has undergone some re-definition. One of the earliest distribution systems was a "Grid" system for underground distribution in cities. Underground cables would be run down every street and be connected at the intersections. Every point on the grid was fed from at least two directions. Faults were expected to "Burn free". Avaiable fault currents were high but not as high as would be the case with modern transformers with much lower impedances.


Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Guinevere]

Thanks All for the answer,
it really helps =)