CONGESTION ISSUES AND
Pradeep kumar bhambhoo (ELE/44/13)
National Institute of Technology,Srinagar(J&K)
• NETWORK CONGESTION
• OBJECTIVE OF CONGESTION MANAGEMENT
• ISSUES WITH CONGESTION ANS IT’S EFFECT
• FEATURES OF CONGESTION MANAGEMENT
• Conversion of Vertically integrated utilities to Open Access
market system [ May 2003,Indian Electricity Act]
• Because of Open Access, Congestion is prime problem for
• Congestion is the overloading in transmission lines. It could
be caused by
o unexpected outages of generation
o sudden increase of load
o tripping of transmission lines
o failure of other equipment
• Transmission congestion can cause additional outages,
increase the electricity prices in some regions and can
threaten system security and reliability.
• When the producers and consumers of the electric
energy desire to produce and consume in total that would
cause the transmission system to operate at or beyond
one or more transfer limit, the system is said to be
• Congestion is a consequence of network constraints
characterizing a finite network capacity that prevent the
simultaneous delivery of power from an associated set of
Graph Showing Congestion:
Objective of Congestion
• Minimized interference of the transmission network in the
market for electric energy
• Secure operation of the power system
• Improvement of market efficiency
• Manage power flow with existing Transmission line
Congestion Management by FACTS
•Congestion can be managed by Facts devices.
•For efficient utilization of the existing network with
penetration of additional power, FACTS devices are used.
•Effective FACTS based power flow control can be applied to
relieve transmission congestion & Improve the transfer
capability of the network with high penetration of power.
While voltage security & voltage stability constraint are
satisfied & transmission net work can be effectively utilized.
Principle of Control
• FACTS is power Electronics based system that provide
dynamic control of the power transfer parameters
transmission voltage, line impedance & phase angle, active
and reactive power when storage becomes viable storage then
they can supply & absorbed active power as well
• Consider unity power factor load, real power transferred is
• Similarly Reactive power transferred is given by:
Issues With Congestion:
• Thermal limit :- The maximum amount of electrical energy
that transmit on transmission line without overheating.
• Voltage limit :- System voltage and change in voltage must
be maintained with the range of acceptable deviation.
• Stability limit :- Transmission system capable of surviving
disturbances through the transient and dynamic period .
Features of Congestion Management
• Economic efficiency
• Minimum intervention
• Non discriminative
• In the end by the help of following methods which can be
followed so that congestion problem can be managed:
• Focus on quantifying the economic risk
• Designing different dispatch and curtailment strategies
o Proper modelling of FACT device
o Optimal placement of FACT device
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Distribution, Vol. 143, pp 313-320, July 1996.
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capability Calculations” PE-321-PWRS-0-10-97, IEEE transaction on power
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Proceedings of 32nd Hawali International Conference on system Sciences-1999
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deregulated environment” Proceeding of IEEE, 88, No.2 , pp 449-451, Feb 2000