2. Outline
Introduction to Microgrid.
Microgrid Operating Modes.
The Need of Microgrid.
Interconnected Microgrids – Power Parks.
Environmental Aspects.
Conventional Grid versus Microgrid.
Advantages & Disadvantages of Microgrid.
Future Directions on Microgrid Research.
References.
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3. Introduction To Microgrid
What is Microgrid?
It is a small-scale power supply network that is designed
to provide power for a small community.
It enables local power generation for local loads.
It comprises of various small power generating sources
that makes it highly flexible and efficient.
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4. Introduction To Microgrid
What is Microgrid?
It is connected to both the local generating units and the
utility grid thus preventing power outages.
Excess power can be sold to the utility grid.
Size of the Microgrid may range from housing estate to
municipal regions.
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5. Introduction To Microgrid
Microgrid Components
Distributed Generation
Loads
Immediate storage
Controller
Point of Common Coupling
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8. Microgrid Operating Modes
Grid Connected Mode:
Utility grid is active.
Static switch is closed
All the feeders are being
supplied by utility grid.
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9. Microgrid Operating Modes
Island Mode:
Utility grid is not supplying power
Static switch is open.
Feeder A, B, C are being supplied
by Microsources.
Feeder D (not sensitive )
is dead.
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10. The Need Of Microgrid
Microgrid could be the answer to our energy crisis.
Transmission losses gets highly reduced.
Microgrid results in substantial savings and cuts
emissions without major changes to lifestyles.
Provide high quality and reliable energy supply to
critical loads
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11. Interconnected Microgrids
Interconnected Microgrids – Power Parks
Practical size of Microgrids is limited to a few MVA.
For larger loads, it is desirable to interconnect many
Microgrids to form a larger Microgrid network called
Power Parks.
The advantages of this Microgrid structure insures
greater stability and controllability for the Power Parks.
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12. Environmental Aspects
Microgrid encourages the use of the renewable energy
sources.
Large land use impacts are avoided.
CO2 Emissions are reduced.
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13. Conventional Grid vs. Microgrid
Efficiency of conventional grid is very low as compared
to Microgrid.
Large amount of energy in the form of heat is wasted in
conventional grid.
Power sources in case of Microgrid (often referred to as
Microsources) are small and are located in close
proximity to load.
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14. Advantages & Disadvantages
Microgrid Advantages
A major advantage of a Microgrid, is its ability, during a utility
grid disturbance, to separate and isolate itself from the utility
seamlessly with little or no disruption to the loads within the
Microgrid.
In peak load periods it prevents utility grid failure by
reducing the load on the grid.
Significant environmental benefits made possible by the use
of low or zero emission generators.
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15. Advantages & Disadvantages
Microgrid Advantages
The use of both electricity and heat permitted by the
close proximity of the generator to the user, thereby
increasing the overall energy efficiency.
Microgrid can act to mitigate the electricity costs to its
users by generating some or all of its electricity needs.
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16. Advantages & Disadvantages
Microgrid Disadvantages
Voltage, frequency and power quality are three main
parameters that must be considered and controlled to
acceptable standards whilst the power and energy balance is
maintained.
Electrical energy needs to be stored in battery banks thus
requiring more space and maintenance.
Resynchronization with the utility grid is difficult.
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17. Advantages & Disadvantages
Microgrid Disadvantages
Microgrid protection is one of the most important challenges
facing the implementation of Microgrids.
Issues such as standby charges and net metering may pose
obstacles for Microgrid.
Interconnection standards needs to be developed to ensure
consistency. IEEE P1547, a standard proposed by Institute
of Electrical and Electronics Engineers may end up filling
the void.
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18. Future Directions on Microgrid
Research
To investigate full-scale development, field demonstration,
experimental performance evaluation of frequency and voltage control
methods under various operation modes.
Transition between grid connected and islanded modes on interaction
phenomena between distribution generation and high penetration of
distributed generation.
Transformation of Microgrid system today into the intelligent,
robust energy delivery system in the future by providing
significant reliability and security benefits.
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19. References
A. A. Salam, A. Mohamed and M. A. Hannan. "TECHNICAL CHALLENGES
ON MICROGRIDS" (DECEMBER 2008)
http://www.arpnjournals.com/jeas/research_papers/rp_2008/jeas_1208_146.pdf
S. Abu-Sharkha, R.J. Arnolde, J. Kohlerd, R. Lia, T. Markvarta, J.N. Rossb, K.
Steemersc, P. Wilsonb, R. Yaoc. "Can microgrids make a major contribution to
UK energy supply?" (September 2004)
http://eprints.ecs.soton.ac.uk/11276/1/Microgrids.pdf
John Stevens. "Characterization of Microgrids in the United States", Sandia
National Laboratories (January 2005)
http://www.electricdistribution.ctc.com/pdfs/RDC_Microgrid_Whitepaper_1-7-05.pdf
Robert H. Lasseter, Paolo Piagi. "Microgrid: A Conceptual Solution", University
of Wisconsin-Madison (June 2004)
http://www.pserc.wisc.edu/ecow/get/publicatio/2004public/lasseterpesc04us.pdf
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20. References
"Integration of Distributed Energy Resources - The CERTS MicroGrid
Concept", Consultant Report (October 2003)
http://www.pserc.org/cgi-
pserc/getbig/researchdo/certsdocum0/certspubli/certsmicrogridwhitepaper.pdf
"Why the Microgrid Could Be the Answer to Our Energy Crisis"
http://www.fastcompany.com/magazine/137/beyond-the-grid.html
"How a Microgrid Works"
http://science.howstuffworks.com/microgrid.htm
“The Rise of MicroGrid Power Networks"
http://www.sustainablefacility.com/Articles/Feature_Article/58905d08bd629010VgnVC
M100000f932a8c0____
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