Comparison of Radial, Loop and Cross-Loop Network
In big cities, the concept of 33 kV ring main is extremely popular and two ring mains are laid: one outer and the other one is one inner. The outer ring main is laid using the panther conductor and the inner ring main is laid using the dog conductor.
The use of these two categories of ring mains gives excellent flexibility to the system and at the time of breakdown, supply could be immediately switched on from another 132 kV substation. Although making any distribution planning for metros, the aspect of outer and inner 33 kV ring mains is very necessary and should be involved for giving uninterrupted supply. Table provides a comparison of the three types of network configurations.
Table: Comparison of radial, loop and cross-loop network
|
Radial Distribution System
|
Loop Distribution System
|
Cross-loop Network distribution System
|
|
- Single path to every group of customers
- Lowest construction cost system
- Simple to plan, design and operate
- No reserve - loss of feeder implies loss of supply
USED IN RURAL AREAS
|
- Double path to every group of customers
- Medium cost system
- Moderately simple to plan, design and operate
- Loss of feeder results only in temporary loss of supply
USED IN URBAN AREAS
|
- Multiple paths to every group of customers
- High cost system
- Complex to plan, design and operate
- Highest reliability
- Used in large cities and for critical loads
USED IN URBAN AREAS
|