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Monday, November 21, 2011

Transmission & Distribution

In India,power plants typically produce 50 cycle/second (Hertz) alternative current (AC) with voltage between 11 KV & 33 KV. electricity is brought from the power plant to consumer though extensive transmission & distribution (T&D) system  comprising distribution network,stage grid & regional grid.

The various stage of the process are given below:-

  • At the power plant site , the 3-phase voltage is generated and stepped up to higher voltage to transmission on cable strung cross over country tower. 
  • High voltage (HV) and Extra high voltage (EHV) is the next stage to transport AC current from the power plant at over long distance like 220 KV,400 KV & 760 KV.for longer distance and higher powers,high voltage are economical.in special case (HVDC) Highh voltage direct current is preferred
  • Sub-transmission network at 132 KV,110 KV,66 KV,33KV constitutes the next link toward to end-users.
  • Distribution network at 11 KV/6.6 KV/3.3 KV constitutes the last link toward to consumers,who is directly connected or though step-down transformer.these transformer bring the voltage to level down to 400V,3-phase 4 wire secondary distribution.The single phase  residential lighting load is connected between any phase and neutral (230V) ,3-phase load is connected across 3 phase line directly.             

The transmission and distribution network include sub-station,line and distribution transformer,containing step-down transformer,reduce the voltage for distribution to industrial, commercial and residential costumers.these substation and distribution line are referred to as the distribution system.


 

Sunday, November 20, 2011

Future Direction in Power Sector

Future Direction;-

The Government of India has envisaged installed capacity of 2,21,000 MV by the year 2012 to meet its mission power to all.the large coal reserves in country provided ready and economical resource and ensure energy security as of now.Hence coal has been identify as the mainstay fuel for the power generation till 2012.the government has also committed to generate  10% of its power from the renewable sources by the year 2012.The overall potential for renewable energy is around 1,72,000 MV.Of this less then 7000 MV has been realized so far.
The entry of renewable energy can help us in meeting present peaking power & general shortage.

Anther step in the direction,is the scheme of allowing Captive Power Generation,which refer to setup by an individual,co-operative society or industries for their own consumption.Industries in the manufacturing sector e.g.cement, aluminum, fertilizer,sugar,paper,steel etc.have their own captive  power plant to supplement the electricity purchased from utilities or producing energy.

         

Power Sector In India

The Electricity in India(Overview):-

An electricity supply system has mainly three component.

  • Power generating units
  • Transmission lines
  • Distribution Sector    
 its Comprise
  • Generating unit that produce electricity;
  • High voltage transmission line that supply electricity over long distance;
  • Low voltage distribution line that transfer electricity to consumers;
  • Substation;which are the part of Electricity transmission & distribution system.where the voltage are transfer to lower level for distributing power to end-users;
  • Energy control center to coordinate the operation of components.