Power Grid Operation and its components

1. POWER GRID
OPERATION
IN INDIA
PREPARED BY:-
MAHIM SRIVASTAVA
EN-3RD YEAR

2. WHAT IS A “GRID” ?
An Interconnected power system covering a major portion of a country’s territory
(or state) is called a Grid. The different state grids may be a interconnected through
transmission lines to form a Grid.
WHAT IS AN “INTER-CONNECTION” ?
Two or more generating stations are interconnected by tie lines. Interconnection
provides the best use of power resources and ensures greater security of supply.
WHY DO WE NEED THIS INTER-CONNECTION ?
1)Reliability
2)Economy
3)Proper Load Sharing

3. ALL POWER-GRID EQUIPMENTS USED
Lightning Arrestor Power Transformer
Current Transformer/Potential Transformer

4. Circuit Breakers Insulators Isolators
Wave Trap

5. LAYOUT DESIGNING – BUS BAR SCHEMES
Single Bus Bar Scheme Main & Auxiliary
Bus Bar Scheme

6. LAYOUT DESIGNING – BUS BAR SCHEMES
Double Bus Bar Scheme Double main &
Aux Bus Bar Scheme

7. THE ELECTRICITY ACT (OVERVIEW)
•The electricity Act, 2003 provides for open access.
•This would create demand from third party for wheeling of
Power.
•No additional wheeling charges unless any new system is
added
•The Electricity (Supply) Act, 1948 was amended in
1991 to provide for creation of private generating
companies for setting up power generating facilities
and selling the power in bulk to the grid or other
persons.

8. CENTRALAUTHORITY SYSTEM
COORDINATE WITH
OTHER
SYSNCHRONOUS GRIDS
(EX NR, ER,NER)
REGIONAL (SYNCHRONOUS GRID)
LOAD DESPATCH CENTRE
STATE LOAD
DESPATCH
CENTRES
CENTRALLY
OWNED LINES
CENTRALLY
OWNED PLANTS
INTER-STATE TIE
LINES
STATE OWNED
HVDC LINES
DISTRIBUTION
SUBSTATION
POWERPLANT
OPERATORS

9. Central Authority System (contd.)
•The Central Electricity Authority of India (CEA) is a statutory
organisation constituted under section 3(1) of Electricity Supply Act 1948
•To develop a sound adequate and uniform national power policy,
formulate short-term and perspective plans for power development
and co-ordinate the activities of planning agencies in relation to the
control and utilisation of national power resources.
•To collect and record the data concerning generation, distribution
and utilisation of power and carry out studies relating to cost,
efficiency, losses, benefits and such like matters.

10. WHAT IS A NATIONAL LOAD DESPATCH CENTRE ?
The main functions assigned to NLDC are:
 Supervision Over the Regional Load Despatch Centres.
 Scheduling and dispatch of electricity over the inter-regional
links in accordance with grid standards specified by the
authority and grid code specified by Central Commission in
coordination with Regional Load Despatch Centres.
 Coordination with Regional Load Despatch Centres for
achieving maximum economy and efficiency in the operation
of National Grid.
 Monitoring of operations and grid security of the National
Grid.
 Coordination for restoration of synchronous operation of
national grid with Regional Load Despatch Centres.

11. SHARING OF TRANSMISSION CHARGES
•Charges for inter-regional lines may be shared by two
contiguous regions on 50 : 50 basis.
•Charges for the regional assets may be shared by the
regional beneficiaries
•If an inter regional asset is used for wheeling by a third
party the balance transmission charges may be shared by
the beneficiaries of the contiguous region on 50 : 50 basis.
WHEELING CHARGES:
•Wheeling is the transportation of electric power (megawatts
or megavolt-amperes) over transmission lines.
•An entity that generates power does not have to own
power transmission lines
•The entity then pays the owner of the transmission
line based on how much power is being moved and
how congested the line is.

12. OWNERSHIP AND COORDINATION
• Inter-State and other transmission links may be owned by
other independent entity (Ex: PGCIL).
• State Electricity Boards can Import or Export a pre decided
amount of power from neighboring states or generators
owned by other entities like National Thermal Power
Corporation.
• State Electricity Boards are divided into
1) Generation companies (GENCOs)
2) Distribution Companies (DISCOs)
3) Transmission Companies(TRANSCOs)
• Overall coordination is done by a Load Dispatch Centre.

13. GENCOS:
The companies which are responsible for power generation are
called as Generation Companies(GENCOs) ex: NTPC
TRANSCOS:
The companies which are responsible for transmission of large
amounts of power are called as Transmission
companies(TRANSCOs) Ex: PowerGrid
DISCOS:
The companies which are responsible for Distribution of the
large amounts of power to the general public are called as
Distribution Companies(DISCOs) Ex: UP-RVVNL

14. NEW DELHI POWER DISTRIBUTION SYSTEM
All three companies mentioned are Distribution Companies

15. DIFFERENT GRIDS OF INDIA

16. SOME LANDMARK EVENTS OF POWERGRID
• 1948 - Growth of supply systems
• 1962- First 220KV Voltage level
• 1967- Interconnection Of state Grids to form
Regional Grids
• 1975- First 400Kv Voltage level
• 1989- HVDC Back to Back
• 1998- Installation of 765 Kv line(Charged at 400Kv)
• 2006- Synchronisation of NR with ER-NER-WR
• 2007- Transmission at 765 Kv
• 2010/11- Installation of 800Kv HVDC Bi-pole Line

18. ANY QUESTIONS ???
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