DESIGN CONCEPTS OF 33/11kV NEW SUBSTATION. Planning 33/11kV Sub-Station. A- Decision of location a-The location should be best suited at the load centre of the 11kV net-work b-Load density and voltage-regulation.
(v) There should have adequate land keeping in view the requirements for installation of required equipments-
Land for 2x3MVA is approx 50x40metres
For staff quarters Approx 3 acres
(vi) Land should be in level and should not have any nallah or road crossing on it.
(vii) The site should be selected so as to accommodate the length of 11kv outgoing feeder to connect the existing net work. It should be possible to be taken out 4-5 numbers of 11kV feeders.
(i) Protection System
(ii) Fire-fighting equipment
(iii) Staff quarters
(i) 630kVA 33/11 step-down (Delta/Dy11)
Most of the Transformers are provided with off-circuit tap Changers.However On Load Tap Changers are being provided in the Power Transformers with capacity of more than 5MVA
A Circuit Breakers
-Switches are Used to isolate equipment for maintenance purposes
Two types of bus bars - Rigid and Strain type
Adequate insulation is required for reliability of supply, safety of personnel and equipment etc.
Current Tranformers are required for protection & metering system
C&R Panels normally consist of
kW-km limit for Rabbit, weasel & squirrel conductors
0.8 P.F. 0.7 P.F.
WHILE DESIGINING THE 33/11 KV SUBSTATIONS, THE DESIGNOR HAS TO KEEP IN MIND THE NEEDS FOR STANDARDISATION.
AVOIDING REPETATION OF DESIGN
REDUCTION IN DRAWING APPROVAL TIME
UNIFORMITY IN THE PRODUCTS
REDUCTION IN PROJECT IMPLEMENTATIONTIME
MINIMUM DOWN TIME