18. Enable transfer of
power from power
surplus regions to
deficit regions.
Enable optimal
development and
utilisation of coal
and hydro
resources, in the
overall interest of
the nation.
Improve
economy,
reliability and
quality of power
supply.
ADVANTAGES
19. In case of any major
disturbance whole Grid
may get collapsed resulting
in total blackout in the
country.
Monitoring of
Grid discipline
will become
more complex.
DISADVANTA
GES
20. Present IR Capacity = 8,500 MW
By the year 2012 = 30,000 MW
500 MW
1200 MW
1000MW
2000MW
500 MW
500 MW
Inter Regional links
22. Introduction to IEGC
The Indian Electricity Grid Code (IEGC) lays
down
• Rules, guidelines and standards to be followed by the
various agencies and participants in the system to plan,
develop, maintain and operate the power system, in the
most efficient, reliable, economic and secure manner,
while facilitating healthy competition in the generation
and supply of electricity.
• Role of Statutory bodies- CEA, CTU, RPC, SLDC, RLDC
23. Evolution of IEGC
First draft prepared by
POWERGRID as CTU in
Mar-99
• Enforced w.e.f 01st
Feb 2000
Approved by CERC in Jan
2000 after public hearing
• Issued on 22nd
Feb 02, enforced w.e.f
01st
April 2002
First revision by IEGC
review panel
• Draft issued by CERC-June 2005,
enforced from 1st
April 2006
Second revision (Regulation
2006)
• June2006, September 2008, March
2009, March 2012
Amendments
• In force from 2nd
April,2012
Fourth revision (Regulation
2012)
24. Special Scheduling Provision for
Renewable Energy (IEGC 2010)
• For new wind energy plants, the new code stipulates that
all fluctuations within ± 30% of schedule will be borne by
interstate grid.
• The new grid code allows the new wind energy generators
to fine-tune their schedules (based on forecasting) to as
close as three hours before actual generation.
25. Role of Regulators (CERC /
SERCs)
Electricity Act 2003
• Section 79 subsection (1) clause (h)
• “The Central Commission shall discharge the following
functions…
• (a)…
• (h) To specify Grid Code having regard to Grid Standards…”
• Section 86 subsection (1) clause (h)
• “The State Commission shall discharge the following
• functions…
• (a)…
• (h) Specify State Grid Code consistent with the Grid Code
specified under clause (h) of subsection (1) of section 79”
26. Objective
Documentation of the principles and procedures
which define the relationship between the various
Users of the Inter-State Transmission System (ISTS),
as well as the Regional and State Load Despatch
Centres.
Facilitation of the operation, maintenance,
development and planning of economic and
reliable National / Regional Grid.
Facilitation for beneficial trading of electricity
by defining a common basis of operation of
the ISTS, applicable to all the Users of the
ISTS.
27. Scope
Applies to
• All parties that connect with and / or utilize the ISTS
DVC
• Treatment similar to SEB
BBMB / SSP
• Treated as intra-state generating stations
28. Structure of IEGC (1)
Role of various Organizations and their linkages
Planning Code for inter-state transmission
Connection conditions
• Procedure for connection to the ISTS
• Site responsibility schedule
Operating Code for Regional Grids
• Operating Policy
• System Security Aspects
• Demand Estimation for operational purposes
• Demand Management
• Periodic Report
• Recovery Procedures
• Event Information
29. Structure of IEGC (2)
Scheduling and Despatch Code
• Procedure for scheduling of ISGS
• Complementary Commercial Mechanisms
• Modality of flow of information between the ISGS and the
NLDC/RLDC/SLDCs and other Regional Entities
31. Operating Code (1)
System Security Aspects
• … no part of the grid shall be deliberately isolated …
• … tripping of any important element to be intimated to the RLDC …
• … generating units shall operate in Restricted Governors mode of
operation …
• … except under emergency … no constituent shall suddenly reduce his
generating output …
• … all generating units shall normally have their automatic voltage
regulators (AVRs) in operation …
• … protection and relay settings shall be coordinated …
• All Regional constituents shall make all possible measures to ensure that
the grid frequency always remains within the 49.5 – 50.2 Hz band …
32. Operating Code (2)
System Security Aspects (contd.)
• … shall provide automatic under frequency and df/dt load shedding…
• … shall also facilitate identification, installation and commissioning of SPS …
• Procedures shall be developed to recover from partial/total collapse …
• … regional constituent shall provide adequate and reliable communication facility
…
• … regional constituent shall send information / data including disturbance
recorder/sequential event recorder output, etc. to RLDC …
• Voltage range (kV rms)
• Nominal-765 / Max-800 / Min-728
• Nominal-400 / Max-420 / Min-360
• Nominal-220 / Max-245 / Min-198
• Nominal-132 / Max-145 / Min-122
• Nominal-110 / Max-121 / Min-99
33. Fault Clearance time & Voltage
limits as per CERC
Nominal System
Voltage ( kV)
Fault Clearing
Time
(milli-second)
Vpf
(kV)
Vf
(kV)
400 100 360.00 60.0
220 160 200.00 33.0
132 160 120.00 19.8
110 160 96.25 16.5
66 300 60.00 9.9
Here Vf= 15% of nominal voltage,
Vpf= 80% of nominal voltage
Source: CERC INDIA
35. Management of Indian
Electricity Grid Code
• IEGC Review panel
• Director (Operation), PGCIL as its
Chairman & convenor
Earlier
• Review Panel disbanded
• Responsibility now vests with CERC
• Review request application to CERC
• CERC can change on its own also
Present
36. Few examples of grid
indiscipline
Non-compliance of RLDC instructions
Switching of ISTS elements without RLDC permission (except under emergency)
Manning of control centers by inadequately qualified & untrained trained personnel
Deliberately isolating part of the grid from the rest of the regional grid
suddenly reducing generating unit output by more than one hundred (100) MW (20 MW
in case of North-Eastern region)
Sudden increase in its load by more than one hundred (100 MW) (20 MW in case of
North-Eastern region)
37. Few examples of grid indiscipline
Not ensuring providing of RTU and other
communication equipment for sending real-time data
to SLDC/RLDC at least before date of commercial
operation of the generating stations or
sub-station/line being connected to ISTS
Protection systems unable to isolate the faulty
equipments within the specified fault clearance time
with reliability, selectivity and sensitivity
Not sending information/data including disturbance
recorder/sequential event recorder output etc., to
RLDC for purpose of analysis of any grid
disturbance/event.
38. How is IEGC enforced?
Non-compliance by RPC/RLDC
• Matter to be reported to CERC by any agency through petitions
Non-compliance by constituents other than RLDC/RPC
• RLDCs to report the matter to CERC
• MS may also report to CERC if the matter can not be solved at RPC forum.
CERC may take appropriate action based on
reports/petitions
CERC may initiate sou-motu actions also.
41. ROLE OF VARIOUS ORGANIZATIONS
AND THEIR LINKAGES
In the light of the Electricity Act, 2003, it has become necessary
to redefine the role of
National Load Despatch Centers (NLDCs),
Regional Load Despatch Centers (RLDCs),
State Load Despatch Centers (SLDC)/Regional Electricity Boards
(REBs),
the Central Transmission Utility (CTU) etc.
and their organizational linkage so as to facilitate development
and smooth operation of Regional Grids and National Grid at
large.
42. National Load Despatch Center
In accordance with section 26 of Electricity
Act, 2003 the National Load Despatch Centre
was established by the Central Government at
the national level:
• For optimum scheduling and despatch of
electricity among the Regional load despatch
centers.
• As an Apex Body to ensure integrated
operation of the National Power System and
discharge its functions.
43. Functions of NLDC
Supervision over the RLDCs.
Scheduling and despatch of electricity over inter-regional links in accordance with Grid standards specified
by the Authority and Grid Code specified by the Central Commission in coordination with RLDCs.
Coordination with RLDCs for achieving maximum economy and efficiency in operation .
Monitoring of operations and grid security of the National Grid.
Supervision and control over inter regional links as may be required for ensuring stability of the power
system under its control.
Co-ordination with Regional Power Committees for regional outage schedule in the national perspective to ensure
optimum utilization of power resources.
44. Coordination with RLDCs for the energy accounting of inter-regional exchange of power.
Coordination for restoration of synchronous operation of National Grid with RLDCs.
Co-ordination for trans-national exchange of Powers.
Providing operational feed-back for National Grid planning to the Authority and the
Central Transmission Utility.
Levy and collection of such fee and charges from the Generating Companies or the licensees
involved in the power system as may be specified by the Central Commission.
45. Role of RLDCs
According to sections 28 and 29 of Electricity Act, 2003, the
functions of RLDCs are as follows:
• The Regional Load Despatch Centre shall be
the apex body to ensure integrated operation
of the power system in the concerned region.
• The Regional Load Despatch Centre shall
comply with such principles, guidelines and
methodologies in respect of wheeling and
optimum scheduling and despatch of
electricity as may be specified in the Grid
Code.
46. The Regional Load Despatch Centre shall-
Be responsible for optimum scheduling and despatch of electricity within the
region, in accordance with the contracts entered into with the licensees or the
generating companies operating in the region
Monitor grid operations & keep accounts of quantity of electricity
transmitted through the regional grid
Exercise supervision and control over the Inter-State transmission system
Be responsible for carrying out real time operations for grid control and despatch of
electricity within the region through secure and economic operation of the regional
grid in accordance with the Grid Standards and the Grid Code.
47. Few Exclusive Functions Of RLDC
System operation and control including inter-state /
interregional transfer of power, covering contingency analysis
and operational planning on real time basis;
Scheduling / re-scheduling of generation;
System restoration following grid disturbances;
Meter data processing;
Compiling and furnishing data pertaining to system
operation;
Operation of regional UI pool account and regional reactive
energy account.
49. State Load Despatch Center (SLDC)
The State Load Despatch Centre shall be the apex body to ensure
integrated operation of the power system in a State.
Be responsible for optimum scheduling and despatch of electricity
within a State, in accordance with the contracts entered into with
the licensees or the generating companies operating in that State.
Monitor grid operations
Keep accounts of the quantity of electricity transmitted through
the State grid.
50. Exercise supervision and control over the intra-
state transmission system
Be responsible for carrying out real time operations
for grid control and despatch of electricity within
the State through secure and economic operation
of the State grid in accordance with the Grid
Standards and the State Grid Code.
51. Under Section 33 of E-Act 2003
The State Load Despatch Centre in a State may give such
directions and exercise such supervision and control as may
be required for ensuring the integrated grid operations
Every licensee, generating company, generating station,
substation and any other person connected with the
operation of the power system shall Comply with the
direction issued by the SLDC
SLDC shall comply with the directions of the RLDC.
52. Day-ahead resource scheduling process
Availability
Declaration
S
L
D
C
Requisition &
Bilateral Agreements
Injection Schedule Drawal Schedule
Revision if any Revision in Requisition
Final
Injection Schedule
Final
Drawal Schedule
09:00
10:00
15:00
18:00
20:00
22:00
R
L
D
C
I
S
G
S
Time
Revisions during
Current day
Revisions during
Current day
0 to 24
hours
Entitlements
54. Control Room of Load Despatch
Centre
In the control room Two experienced Assistant Executive
Engineers, 1 or 2 FAX operators are working round the clock
in 3 shifts.
The two shift in charge Engineers continuously monitor the
system depending upon the online data and take the necessary
action to maintain the system safe and secure.
One Executive Engineer in charge of Grid operation is also
supervising the activities taking place in the control room for
smooth running.
57. Duties and Responsibilities of a Load
despatch manager in SLDCs and RLDCs
Monitoring of system parameters and security
To ensure the integrated operation of the power system
grid in the region
System studies planning and contingency analysis
Analysis of tripping / disturbances and facilitating immediate
remedial measures
58. CONTINUED………
Daily scheduling and operational planning
Facilitating bilateral and inter regional exchanges
Computation of energy dispatch and drawl values using
SEMs
Augmentation of telemetry , communication and
computational facilities
59. POWERGRID is Responsible for Grid
Management / System Operation of the five
Regional Load Despatch Centers with load
despatch manager (RLDCs) .
RLDCs manager - Responsibilities
• Apex Body for Integrated Grid Operation of the Region
• Scheduling and Despatch of Electricity on real time basis
• Energy Accounting
• Supervision and Control of Inter – State Transmission System
• Ensure Grid Security and adherence to Indian Electricity Grid
Code (IEGC)
63. What is Smart Grid?
A smart grid puts information and communication technology into electricity
generation, delivery, and consumption, making systems cleaner, safer and more reliable
and efficient.
Modernization of the electricity delivery system so that it monitors, protects and
automatically optimizes the operation of its interconnected elements – from the central
and distributed generator through the high-voltage network and distribution system, to
industrial users and building automation systems, to energy storage installations and to
end-use consumers and their thermostats, electric vehicles, appliances and other
household devices.
The Smart Grid in large, sits at the intersection of Energy, IT and Telecommunication
Technologies.
64. The Smart Grid is a combination of hardware, management
and reporting software, built atop an intelligent
communications infrastructure.
In the world of the Smart Grid, consumers and utility
companies alike have tools to manage, monitor and respond
to energy issues.
The flow of electricity from utility to consumer becomes a
two-way conversation, saving consumers money, energy,
delivering more transparency in terms of end-user use, and
reducing carbon emissions.
65. Need of Smart Grid
Increasing demand:
High Aggregate Technical & Non Technical, Losses:18%-62%
Ageing assets…transformers, feeders etc.,
Grid to carry more power: Need for, Reliability and greater Security
Billing and collections: Profitability of distribution companies
Energy mix: Need for Renewable to reduce carbon footprint
66. Integrate isolated technologies : Smart Grid enables better energy
management.
Proactive management of electrical network during emergency
situations.
Better demand supply / demand response management.
Better power quality
Reduce carbon emissions.
Increasing demand for energy : requires more complex and critical solution
with better energy management
67. Smart Grid Applications
67
Distributed Generation and Alternate Energy Sources
Self-Healing Wide-Area Protection and Islanding
Asset Management and On-Line Equipment Monitoring
Demand Response and Dynamic Pricing
Participation in Energy Markets
Shared Information – Continuously Optimizing – Intelligent
Responses!
Real-time Simulation and Contingency Analysis
69. Smart Grid Benefits
Economic Development
• New Jobs: The manufacture, installation, operation and
maintenance of the smart grid and its components will
create new jobs within the state.
• Innovation: Smart grid innovation will enable the growth of
business while rewarding customers with valuable new
products.
• Lower Costs: Costs rise over time and energy is no
exception, but the smart grid should provide less costly
energy than otherwise would be possible. As such, it will
save customers money which can be invested or consumed
as they choose.
70. Customer Satisfaction
• Higher Customer Satisfaction: The combination of lower
costs, improved reliability and better customer control will raise
satisfaction among all types of customers (residential,
commercial, industrial, institutional).
• Improved Reliability: Smart grid will reduce and shorten
outages and improve the quality of power.
• Customer Energy/Cost Savings: As pricing becomes more
transparent and is aligned with the underlying economics of
generation and distribution, customers’ decisions to save money
will benefit society as well
• Highest Security: Security will be incorporated into the design of the
smart grid and will require the implementation of practices and procedures
by individual stakeholders. In this way, the physical and cyber security risks
can be managed to the highest standards possible.
