The document summarizes key discussions from a workshop on congestion management. It defines congestion and discusses approaches to managing it in different time horizons from long-term planning to real-time operations. It also covers regulatory initiatives in India related to congestion charges and modifying grid codes. Specifically, it provides examples of how contingency arrangements and market-based approaches like congestion charges have helped alleviate congestion on the Indian transmission system.
Congestion management using facts devices in deregulated power systemeSAT Journals
Abstract The deregulated power system offers more benefits to the customers so that it is quite popular in now days. The Increased power demand has forced the power system to operate very closer to its stability limits. This paper presents a new method to mitigate congestion in a deregulated Power system. The Increased power demand has forced the power system to operate very closer to its stability limits. So Transmission congestion, Voltage instability and power loss problems are arise in the power system. These are very serious problems which cause damage to the power system Congestion is a tough task in Deregulated power system. This paper deals with the best location for TCSC using priority list to have minimum total congestion rent and minimum total generation cost .The Simulation results were successfully tested on modified IEEE 9 bus system using Power world simulator 11.0. Keywords— Deregulated power system, Congestion, Thyristor Controlled Series Capacitor (TCSC), Reactive power loss, Power Transfer capability,
Congestion management using facts devices in deregulated power systemeSAT Journals
Abstract The deregulated power system offers more benefits to the customers so that it is quite popular in now days. The Increased power demand has forced the power system to operate very closer to its stability limits. This paper presents a new method to mitigate congestion in a deregulated Power system. The Increased power demand has forced the power system to operate very closer to its stability limits. So Transmission congestion, Voltage instability and power loss problems are arise in the power system. These are very serious problems which cause damage to the power system Congestion is a tough task in Deregulated power system. This paper deals with the best location for TCSC using priority list to have minimum total congestion rent and minimum total generation cost .The Simulation results were successfully tested on modified IEEE 9 bus system using Power world simulator 11.0. Keywords— Deregulated power system, Congestion, Thyristor Controlled Series Capacitor (TCSC), Reactive power loss, Power Transfer capability,
The amount of electric power that can be moved or transferred reliably from one area to another area of the interconnected transmission systems by way of all transmission lines (or paths) between those areas under specified system conditions……….16-Mar-2007(FERC)
As per 1995 document of NERC, following conditions need to be satisfied:
all facility loadings in pre-contingency are within normal ratings and all voltages are within normal limits
systems stable and capable of absorbing the dynamic power swings
before any post-contingency operator-initiated system adjustments are implemented, all transmission facility loadings are within emergency ratings and all voltages are within emergency limits”
The significance of power factor correction (PFC) has long been visualized as a technology requirement for improving the efficiency of a power system network by compensating for the fundamental reactive power generated or consumed by simple inductive or capacitive loads. With the Information Age in full swing, the growth of high reliability, low cost electronic products have led utilities to escalate their power quality concerns created by the increase of such “switching loads.” These products include: entertainment devices such as Digital TVs, DVDs, and audio equipment; information technology devices such as PCs, printers, and fax-machines; variable speed motor drives for HVAC and white goods appliances; food preparation and cooking products such as microwaves and cook tops; and lighting products, which include electronic ballasts, LED and fluorescent lamps, and other power conversion devices that operate a variety of lamps. The drivers that have resulted in this proliferation are a direct result of the availability of low-cost switch-mode devices and control circuitry in all major end-use segments: residential, commercial, and industrial.
A New approach for controlling the power flow in a transmission system using ...IJMER
Electrical power systems is a large interconnected network that requires a careful design to maintain the system with continuous power flow operation without any limitation. Flexible Alternating Current Transmission System (FACTS) is an application of a power electronics device to control the power flow and to improve the system stability of a power system. Unified Power Flow Controller (UPFC) is a new concept for the compensation and effective power flow control in a transmission system.Through common DC link, any inverters within the UPFC is able to transfer real power to any other and there by facilitate real power transfer among the line. In this paper a test system is simulated in MATLAB/SIMULINK and the results of the network with and without UPFC are compared and when the voltage sag is compensated, reactive power is controlled and transmission line efficiency is improved.
Transmission Congestion Management by Using Series Facts Devices and Changing...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
The amount of electric power that can be moved or transferred reliably from one area to another area of the interconnected transmission systems by way of all transmission lines (or paths) between those areas under specified system conditions……….16-Mar-2007(FERC)
As per 1995 document of NERC, following conditions need to be satisfied:
all facility loadings in pre-contingency are within normal ratings and all voltages are within normal limits
systems stable and capable of absorbing the dynamic power swings
before any post-contingency operator-initiated system adjustments are implemented, all transmission facility loadings are within emergency ratings and all voltages are within emergency limits”
The significance of power factor correction (PFC) has long been visualized as a technology requirement for improving the efficiency of a power system network by compensating for the fundamental reactive power generated or consumed by simple inductive or capacitive loads. With the Information Age in full swing, the growth of high reliability, low cost electronic products have led utilities to escalate their power quality concerns created by the increase of such “switching loads.” These products include: entertainment devices such as Digital TVs, DVDs, and audio equipment; information technology devices such as PCs, printers, and fax-machines; variable speed motor drives for HVAC and white goods appliances; food preparation and cooking products such as microwaves and cook tops; and lighting products, which include electronic ballasts, LED and fluorescent lamps, and other power conversion devices that operate a variety of lamps. The drivers that have resulted in this proliferation are a direct result of the availability of low-cost switch-mode devices and control circuitry in all major end-use segments: residential, commercial, and industrial.
A New approach for controlling the power flow in a transmission system using ...IJMER
Electrical power systems is a large interconnected network that requires a careful design to maintain the system with continuous power flow operation without any limitation. Flexible Alternating Current Transmission System (FACTS) is an application of a power electronics device to control the power flow and to improve the system stability of a power system. Unified Power Flow Controller (UPFC) is a new concept for the compensation and effective power flow control in a transmission system.Through common DC link, any inverters within the UPFC is able to transfer real power to any other and there by facilitate real power transfer among the line. In this paper a test system is simulated in MATLAB/SIMULINK and the results of the network with and without UPFC are compared and when the voltage sag is compensated, reactive power is controlled and transmission line efficiency is improved.
Transmission Congestion Management by Using Series Facts Devices and Changing...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
Authors: (i) Prashanth Lakshmi Narasimhan,
(ii) Mukesh Ravichandran
Industry: Automobile -Auto Ancillary Equipment ( Turbocharger)
This was presented after the completion of our 2 months internship at Turbo Energy Limited during our 3rd Year Summer holidays (2013)
Enhanced frequency response is the primary revenue
stream currently available to (battery) energy storage.
• Capacity market does not limit duration of supply
provision.
• Constraint payment spending has and is expected to
continue to increase. How to unlock these costs for
energy storage.
ESKOM will show you how to:
Understanding what risks Eskom face when it comes to grid connection so you know if your project’s timings are structured appropriately
Discussing whether developers can absorb any of the risk to benefit both themselves and Eskom in creating a quicker and less risky connection
Hearing lessons learnt from REIPPP programme so far with reference to grid integration from Eskom and understand how you can aid a smooth connection
Overview of the FlexPlan project. Focus on EU regulatory analysis and TSO-DSO...Leonardo ENERGY
Webinar recording at https://youtu.be/4s2GGlu-ylc
The FlexPlan project (https://flexplan-project.eu/) aims at establishing a new grid planning methodology making use of storage and flexible loads as an alternative to the build-up of new grid elements. After introducing the project, the webinar will focus on pan-European grid planning regulation and present practices of TSOs and DSOs.
Intervención de David Trebolle, Unión FENOSA, en el marco de la jornada técnica Smartgrids - The making of en colaboración con IMDEA.
3 de noviembre de 2010
Show and Tell - Flexibility & Hydrogen Integration.pdfSIFOfgem
This is the last in a series of 'Show and Tell' webinars from the Ofgem Strategic Innovation Fund Discovery phase, covering projects focused on increasing flexibility sources in the energy system and hydrogen deployment and integrations.
The energy system is made up of a complex range of activity across networks, markets, supply, and demand. A range of organisations play crucial roles in managing various parts of this system. Working across traditional boundaries can create opportunities for better integration of services to consumers, who typically experience the system as a whole. Innovative whole system solutions are required to optimise the system, reducing costs whilst enhancing the experience of consumers.
You will hear from SIF projects looking to increase sources of energy system flexibility and integrate hydrogen effectively into the system.
The Strategic Innovation Fund (SIF) is an Ofgem programme managed in partnership with Innovate UK, part of UKRI. The SIF aims to fund network innovation that will contribute to achieving Net Zero rapidly and at lowest cost to consumers, and help transform the UK into the ‘Silicon Valley’ of energy, making it the best place for high-potential businesses to grow and scale in the energy market.
For more information on the SIF visit: www.ofgem.gov.uk/sif
Or sign-up for our newsletter here: https://ukri.innovateuk.org/ofgem-sif-subscription-sign-up
Introduction
Data aquisition
Generation & demand
RES potential
Transmission network
Corridor selection
Costs assumption
Methodology and modeling
Results of the simulation
Conclusions and recommendations
The merits of integrating renewables with smarter grid carimetRick Case, PMP, P.E.
A critical look at the response a grid will need with increasing penetration levels of Variable Renewable Resouces (VRRs) on a grid and the SMART solutions required to maintain grid stability.
NPTI 15th batch Indian electricity grid code (IEGC)Ravi Pohani
from state to regional to national grid and now towards area grid again for better controllability of power flow.
it encompasses operation code, metering code, dispatch code, etc.
Similar to Srldc 28 May2013_congestionEnergy & Power Meet (20)
Hydro is the most well-established form of renewable electricity production.
Hydro comprised about 80% of all of the renewable electricity capacity in the world, and accounted for about 20% of global electricity production capacity.
Hydropower is also the most efficient means we know of to convert energy into electricity.
Typically 85%-95% of the energy in water is converted to electricity, compared to 15%-20% for PV solar, 35%-45% for wind, and 30%-45% for coal.
Assumptions: Strategy already defined Strategy not subject to sudden chang...PRIYANK JAIN
Assumptions:
Strategy already defined
Strategy not subject to sudden change
Strategy Development separate from Implementation
Framework for Strategy Implementation
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
2. Outline
• Congestion definitions
• Congestion Management in different time horizons
– Long term
– Medium term
– Operational Planning
– Real time
• CERC procedure on congestion charges in real time
3. Pillars of Market Design
Sally Hunt – ‘ Making Competition Work in Electricity’
4. Congestion in Power System
“Congestion is a situation where the demand
for transmission capacity exceeds the
transmission network capabilities, which
might lead to violation of network security
limits, being thermal, voltage stability limits or
a (N-1) contingency condition.”
CIGRE_WG_C5.04_TB_301
4
5. Indian Electricity Grid Code 2010
• ‘Congestion’ means a situation where the
demand for transmission capacity exceeds the
Available Transfer Capability;
First formal definition of congestion in power
system in our statute wef 3rd May 2010!!!
7. Visibility of congestion
• Visible to the market players
– “If for a given interconnection, there is more demand for
cross border capacity than commercially available, the
interconnection is also treated as congested, meaning no
additional power can be transferred. This congestion is
visible for market players as a limit on their cross-border
transactions.”- CIGRE_WG_C5.04_TB_301
• Invisible to the market players
– “It is possible that even though the available commercial
interconnection capacity is not fully allocated to market
players, some lines, being internal or cross-border, become
overloaded. This physical congestion is a problem of the
System Operator and has to be dealt with by this entity.”
CIGRE_WG_C5.04_TB_301
7
To be handled before-the fact
To be handled in real-time
8. Congestion visible to the market
• “The more transactions and the more meshed
the network, the higher the chance for
mismatch between commercial exchange and
physical flows.” CIGRE_WG_C5.04_TB_301
Congestion
Sign of growth and vibrant market
Natural corollary to Open Access
Existing transmission system was not planned with
short-term open access in mind
Security margins have been squeezed
‘Pseudo congestion’ needs to be checked
8
9. Real-time Congestion types
• Internal congestion (Intra-zonal)
– Within a single System Operator’s control area
• Cross-border (Inter zonal)
– Also called seams issue
– Several System Operators involved
Was not experienced
-Regional grids were small
-Trades were limited
9
Experienced occasionally under
- Grid Contingencies
- Skewed conditions in grid
Aggressive Open Access trades
10. Open Access Theory & Practice
Forum of Regulators report, Nov-08
“For successful implementation of OA,
the assessment of available transfer
capability (ATC) is very important. A
pessimistic approach in assessing the
ATC will lead to under utilisation of the
transmission system. Similarly, over
assessment of ATC will place the grid
security in danger.”
10
11. Declaration of Security Limits
• “In order to prevent the violation of security
limits, System Operator SO must define the
limits on commercially available transfer
capacity between zones.” CIGRE_WG_C5.04_TB_301
• “System Operators try to avoid such
unforeseen congestion by carefully assessing
the commercially available capacities and
reliability margins.” CIGRE_WG_C5.04_TB_301
11
12. Cross border capacity available for trade
• “Physical capacity connecting zones A and B is
sum of 1-3 and 2-3 physical line capacities.
However, the cross border capacity available
for commercial trade would be less or at most
equal to the sum of capacities of cross border
lines individually.” CIGRE_WG_5.04_TB_301
1
2
3
A B
12
13. 13
Intra-day STOA
Day-ahead STOA
Collective (PX) STOA
First Come First Served STOA
Advance Short Term Open Access (STOA)
Medium Term Open Access (MTOA)
Long Term Open Access (LTOA)
Reliability Margin (RM)
Available Transfer Capability is
Total Transfer Capability less Reliability Margin
TTC ATC
RM
15. Gross Transmission Capacity (GTC) vis a vis
Net Transmission Capacity (NTC) in Europe
Corridor GTC NTC Difference NTC/GTC (%)
France to United Kingdom 2000 2000 0 100%
United Kingdom to France 2000 0 2000 0%
Denmark (East) to Sweden 2010 1700 310 85%
Sweden to Denmark (East) 2010 1300 710 65%
Italy to Slovenia 2017 480 1537 24%
Slovenia to Italy 2017 380 1637 19%
Austria to Hungary 2124 500 1624 24%
Hungary to Austria 2124 200 1924 9%
Sweden to Finland 2230 1800 430 81%
Finland to Sweden 2230 1600 630 72%
Czech Republic to Austria 2249 600 1649 27%
Austria to Czech Republic 2249 0 2249 0%
Italy to Austria + Slovenia 2274 0 2274 0%
Lituania to Kaliningrad 2287 700 1587 31%
Slovakia to Hungary 2492 1100 1392 44%
Hungary to Slovakia 2492 200 2292 8%
Poland to Slovakia 2504 750 1754 30%
Slovakia to Poland 2504 750 1754 30%
Courtesy:
ENTSOE 15
16. NTC Vs GTC Among EU Countries
For Corridors Up to 1000 MW
17. NTC Vs GTC Among EU Countries
For Corridors Up to 5000 MW
18. NTC Vs GTC Among EU Countries
For Corridors Up to 16000 MW
Gross Total Capacity & Net Transfer Capability Among EU Countries
y= 0.21x
0
2000
4000
6000
8000
10000
12000
14000
16000
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000 13000 14000 15000 16000
Gross Total Capacity(MW)
NetTransferCapability(MW)
~ 21%
20. Transmission Capacity ( TC ) vis-à-vis
Available Transfer Capability ( ATC ) in Brazil
TRUNK
TC
( MW )
ATC
( MW )
ATC/TC
(%)
North - Southeast/Midwest
Interconnection
( from North to Southeast)
4200
n-1 3400 81
n-2 1700 40
WITH SPS 4100 98
North - Southeast/Midwest
Interconnection
( from Southeast to North )
n-1 3000 71
Foz do Iguaçu – Ivaiporã
765 kV trunk
6450
n-2 3600 56
WITH SPS 5300 82
Southeast/Midwest - South
Interconnection
17180 n-2 9500 55
440 kV trunk
feeding São Paulo
14500
n-2 9600 66
WITH SPS 10200 70
20Courtesy: ONS Brazil
21. Handling congestion in different time horizons
• Long term planning……….3-5 years time frame
– Several scenarios and uncertainties to be factored
– Probabilistic vs deterministic
– High Impact Low probability events
– Operational feedback by NLDC/RLDCs as per
section 4j of NLDC Rules 2005.
http://www.posoco.in/documents/operational-
feedback
22. Handling congestion in different time horizons
• Medium term planning……….0-3 years time
frame
– Network augmentation difficult
– Temporary re-configuration of network possible
– Pro-rata still the main method in Medium Term
Open Access (MTOA)
• Auctions another possibility
23. Lanco Amarkantak (2 x 300 MW)
400 kV Lanco to Sipat section used to constraint West to East TTC
24. Lanco Amarkantak (2 x 300 MW)
Contingency
Arrangement
Implemented
in May 2010
25. Contingency arrangement at CGPL Mundra in 2011
Single line sketch showing proposed bunching arrangement for Bhachau to Vadavi & Chorania D/C TL
D/C
CGPL
Mundra
400 kV
Bhachau S/S
PGCIL
S/C S/C
400 kV 25 km 400 kV
Chorania S/S D/C Bunching point D/C Vadavi S/S
GETCO 192 kms 257 kms GETCO
26. 400 kV Maithon-Koderma arrangement
• Final arrangement
– 400 kV Maithon- Gaya D/C (Quad)
– 400 kV Koderma-Gaya D/C (Quad)
– Forest clearance and ROW problem near Gaya
• Interim arrangement
– 400 kV Maithon-Koderma D/C
27.
28. Benefit
• Reduction in flow of 400 kV Kahalgaon-
Biharsariff D/C and Kahalgaon–Banka-
Biharshariff D/C, which is a constraint for ER-
NR TTC
• Enhancement of ER-NR TTC.
29. Congestion in Operational Planning horizon
• Priority based rules
• Pro-rata rationing
• Auctioning
– Explicit Auction…………e-bidding under STOA
– Implicit Auction…………Power Exchange Day Ahead
– Hybrid
• Market splitting
• Market coupling
29
30. Congestion Management
Lessons learnt in Indian context
• Firmness in STOA schedules
– “Use it or Lose it”
• Valuing transmission instead of pro rata
• Market splitting
30
31. Congestion Management in real time
– Classical
– Compliance to Standards and Grid Code
– Topology change
– Re-dispatch
– Curtailment
– Market based
– Commercial signals (Congestion Charge)
– Ancillary Market
• Out of merit generation scheduled to pool
• Reactive power charge- synchronous condenser operation
31
32. Congestion Management in real time
• Counter trading
• Re-dispatching (Out of merit generation)
• Locational Marginal Pricing (LMP)
λnode = λ deviation price + λcongestion charge + λlosses
• Transmission Loading Relief (TLR)
All these methods would result in significant rise in
total cost.
“Price for system security”
32
33. Regulatory initiatives
• Modifications in Grid Code & other regulations
– Frequency band tightening
– Cap on UI volume, Additional UI charge
– Inclusion of new definitions (TTC, ATC, Congestion)
• Congestion Charge Regulation
– Congestion Charge Value, Geographical
discrimination
– Procedure for Assessment of Transfer Capability
– Procedure for Implementation of Congestion Charge
33
34. Congestion charges in real time……..CERC orders
• Order dated 7th Nov 2007 in petition no 116/2007
– Congestion charges @300 paise/kWh for Northern region
– Flexibility given to NRLDC
– Irrespective of frequency
– Applied on two occasions in NR.
• Regulations dated 22nd Dec 2009 on congestion charges
in real time
– Procedure approved by CERC vide order dated 11th June 2010
– Modified procedure ordered on 22nd April 2013
36. Antecedent condition
31st Jan-08
Morning hours
Congestion Charge
1400 hrs0945 hrs 2000 hrs
Improvement in voltage profile
subsequent to imposition of
congestion charge
31st Jan-08, 1400 hrs- 1830 hrs
37. Imposition of Congestion charge in NR
15th September 2008, 0300 hrs to 0800 hrs
Exactly a week later, NTPC Dadri complex plus HVDC Rihand Dadri bipole tripped
During night hours. Low load conditions in NR averted a major blackout.
39. Congestion alleviation
Gen: G2
Load: P2
Gen: G1
Load: P1
Downstream system
Upstream system
Line flow = (G1 – P1) OR (P2 – G2)
For congestion alleviation
viz. reducing flow
on the lines connecting the two systems
both upstream and downstream actions
are required for maximum benefit
considering the
frequency dependence on load
40. Congestion alleviation –only upstream actions
Gen: G2
Load: P2
Gen: G1
Load: P1
Downstream system
Upstream system
Line flow = (G1 – P1) OR (P2 – G2)
For a reduction of generation ∆ P
in upstream system,
the line flow would reduce by
∆ P ( P2 )
(P1 + P2)
41. Congestion alleviation – only downstream
actions
Gen: G2
Load: P2
Gen: G1
Load: P1
Downstream system
Upstream system
Line flow = (G1 – P1) OR (P2 – G2)
For a reduction of load ∆ P
in downstream system,
the line flow would reduce by
∆ P ( P1 )
(P1 + P2)
42. Congestion alleviation – both upstream and
downstream actions
Gen: G2
Load: P2
Gen: G1
Load: P1
Downstream system
Upstream system
Line flow = (G1 – P1) OR (P2 – G2)
For a reduction of generation and load ∆ P
each in upstream and downstream system,
the line flow would reduce by
∆ P
43. Relative size of systems
Downstream system
Upstream system
If upstream system is very small
compared to the downstream system
maximum benefit accrues from
generation reduction upstream
viz. actions in the smaller sub-system
44. Relative size of systems
Downstream system
Upstream system
If downstream system is very small
compared to the upstream system
maximum benefit accrues from
load reduction downstream
viz. actions in the smaller sub-system
46. Areas under which modifications have been carried out
• Methodology for assessment of TTC/TRM/ATC
• Declaration of congestion in real time
• Applicability of congestion charge
47. Declaration of Congestion in real time-Procedures
• 5.1. SLDCs/ RLDCs/ NLDC shall have a display available in their web-sites
showing TTC, TRM, ATC declared in advance. Real time power flow in the
corridor for which TTC has been declared shall be displayed alongside for
comparison. The voltage of the important nodes in the grid
downstream/ upstream of the corridor shall also be displayed(Format II)
• 5.2. A corridor shall be considered congested under the following
circumstances:
• 5.2.1. Grid voltage in the important nodes downstream/ upstream of the
corridor is beyond the operating range specified in the IEGC and/or
• 5.2.2. The real time power flow along a corridor is such that n-1 criteria
may not be satisfied.
• 5.2.3. One or more transmission lines in the corridor are loaded beyond
the normal limit specified in CEA Manual on Transmission Planning
Criteria.
48. Declaration of Congestion in real time-Procedures
• 5.3. Whenever actual flow on inter/ intra regional link/ corridor exceeds ATC and
security criteria as mentioned in clause 5.2 above are violated RLDC, NLDC may
issue a warning notice. In case SLDC observes congestion within the intra State
grid it shall inform the respective RLDC which in turn shall inform the NLDC. The
notice for congestion shall be communicated to all the Regional entities
telephonically or through fax/ voice message/ e-mail and through postings on
website and making the same available on the common screen at NLDC/ RLDCs/
SLDCs. The format of the notice is enclosed as Format III.
• 5.4 If the power flow on the corridor is as per the schedule, but the congestion
has been caused by forced outages of a transmission line in the corridor, which
occurs after the drawal schedule has been fixed, then open access transactions
shall be curtailed in the priority given in the Central Electricity Regulatory
Commission (Grant of Connectivity, Long-term Access and Medium-term Open
Access in inter-State Transmission and related matters) Regulations, 2009
followed by revision of TTC, TRM and ATC.
49. Declaration of Congestion in real time-Procedures
• 5.5 If the power flow on the corridor is as per the schedule and the
corridor is congested due to either of the circumstances mentioned in
clauses 5.2.1 and 5.2.3 of this procedure then TTC, TRM and ATC shall be
revised accordingly.
• 5.6 If violation of TTC limits persists for 2 time-blocks not counting the
time-block in which warning notice was issued by RLDC and no
affirmative action is taken by the defaulting agency, NLDC/ RLDC(s) shall
issue a notice for application of congestion charge. This notice shall be
communicated to all the concerned Regional entities telephonically or
through fax message and through postings on website and the same
shall also be made available at the common screen at NLDC/ RLDCs/
SLDCs. The format is enclosed as Format-IV.
50. Declaration of Congestion in real time-Relevant Modifications
• 5.2.2:The real-time power flow along a corridor exceeds the ATC for that
corridor for continuously one time block of 15-minute
-deleted under points for consideration of corrridor congestion
• The real time power flow along a corridor is such that n-1 criteria may not be
satisfied.
-modified clause
• 5.6:If congestion persists for 2 time-blocks not counting the time-block in
which warning notice was issued by RLDC and no affirmative action by the
defaulting agency is taken, NLDC/ RLDC(s) shall issue a notice for application
of congestion charge. This notice shall be communicated to all the
concerned
-deleted under applicability of congestion where ATC was meant
• If violation of TTC limits persists for 2 time-blocks not counting the time-
block in which warning notice was issued by RLDC and no affirmative action
is taken by the defaulting agency, NLDC/ RLDC(s) shall issue a notice for
application of congestion charge.
-inserted clause
51. Applicability of Congestion Charge-Summary
• 6.1. Congestion Charge –Rs.5.45/- per unit(not defined in the procedures)
• 6.2. Congestion charge would be levied for
• a) over drawal or under-injection in the importing control area and
• b) under drawal or over-injection in the exporting control area.
• 6.3. Congestion charges may also become applicable for an intra-regional corridor
of one region, if the congestion is attributable to other regional entities of other
region.
• 6.4. Congestion charge shall be applicable only after two time blocks from the
time of issuing the notice, not counting the time block in which notice is issued.
• 6.5. Congestion charge shall be withdrawn after the power flow on the affected
transmission link/ corridor has come down to the ATC and remains at this level
for one time block. NLDC/ RLDC shall communicate to all concerned Regional
entities telephonically or through fax message/ e-mail and through postings on
website and making available the same on the common screen available at
NLDC/ RLDCs/ SLDCs for lifting of congestion charge. The format of the notice is
enclosed as Format-V.
52. Applicability of Congestion Charge-Relevant Modifications
• 6.2:At frequency below 50 Hz, congestion charge would be levied for
over drawal or under-injection in the importing control area and at
frequencies above 50 Hz, congestion charge would be levied for under
drawal or over-injection in the exporting control area
-deleted under applicability of congestion charge
• 6.2:Congestion charge would be levied for
a) over drawal or under-injection in the importing control area and
b) under drawal or over-injection in the exporting control area.
-inserted
• Minor changes in format-I
53. Methodology for TTC/RM/ATC computation-Relevant Modifications
• 3.6.9:Normal operating limit for an Inter connecting transformer shall be 90 % of its
Maximum Continuous Rating (MCR)
-deleted
• 3.6.9Permissible Normal and emergency limits for transmission elements shall be
as defined in the (CEA Manual on Transmission Planning Criteria).
-final clause
• 3.9During assessment of Total Transfer Capability it shall be ensured that:
• 3.9.1. All transmission element loadings in the base case are within normal
operating limits and the voltages remain within operating range defined in the
IEGC.
• 3.9.2. All transmission element loadings after a credible contingency are within
emergency ratings and grid voltage is within the operating range as defined in the
IEGC.
-deleted
• 3.9:During assessment of Total Transfer Capability it shall be ensured that the
conditions specified in CEA Manual on Transmission Planning Criteria are met after
credible n-1 and n-1-1 contingencies.
-final clause
54. Methodology for TTC/RM/ATC computation-Relevant Modifications
• 3.10.4: Stability under n-1-1 contingency of a temporary single phase to
ground fault on a 765 kV line close to the bus or a permanent single
phase to ground fault on a 400 kV line close to the bus
• 3.10.5:Angular difference of 30 degrees between adjacent buses under
n-1 contingency
-additional insertion
• 3.11.2: Single largest anticipated in feed into the control area/ group of
control area (which could be a combination of States for the purpose of
Power Exchange and for others)/ region.
-deleted under basis of TRM computation