This document outlines a presentation on microgrids. It begins with an introduction that defines a microgrid as a small-scale power supply network designed to provide power for a small community using local power generation. It then covers microgrid operating modes when connected or disconnected from the main grid, the need for microgrids, advantages like efficiency and reliability, challenges around protection and interconnection, and future research directions like control methods under various operating modes. In total, the presentation contains 22 slides covering these topics on microgrids.

1. Shahab Ahmad Khan
Reshadat Ali
Sharib Hussain
06 EEB 127
06 EEB 158
06 EEB 168
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2. Outline
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⚫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 Directionson Microgrid Research.
⚫References.

3. Introduction To Microgrid
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⚫What is Microgrid?
⚫It isa small-scale powersupply network that is designed
to provide power fora small community
.
⚫Itenables local powergeneration for local loads.
⚫Itcomprises of various small powergenerating sources
that makes it highly flexibleand efficient.

4. Introduction To Microgrid
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⚫What is Microgrid?
⚫It isconnected to both the local generating unitsand the
utilitygrid thus preventing poweroutages.
⚫Excess powercan be sold to the utilitygrid.
⚫Sizeof the Microgrid may range from housing estate to
municipal regions.

5. Introduction To Microgrid
⚫Microgrid Components
⚫Distributed Generation
⚫Loads
⚫Immediatestorage
⚫Controller
⚫Point of Common Coupling
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6. 8/25/2009
Typical Microgrid is shown below:
6

7. 8/25/2009
Pomelo, Indonesia - Village microgrid
7

8. Microgrid Operating Modes
⚫Grid Connected Mode:
⚫ Utilitygrid is active.
⚫ Staticswitch is closed
⚫ All the feedersare being
supplied byutilitygrid.
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9. Microgrid Operating Modes
⚫Island Mode:
⚫ Utilitygrid is not supplying power
⚫ Staticswitch is open.
⚫ FeederA, B, C are being supplied
by Microsources.
⚫ Feeder D (not sensitive )
isdead.
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10. The Need Of Microgrid
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⚫Microgrid could be theanswer toourenergycrisis.
⚫Transmission losses gets highly reduced.
⚫Microgrid results in substantial savings and cuts
emissionswithout majorchanges to lifestyles.
⚫Provide high qualityand reliableenergy supply to
critical loads

11. Interconnected Microgrids
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Interconnected Microgrids – Power Parks
⚫Practical sizeof Microgrids is limited toa few MVA.
⚫For larger loads, it is desirable to interconnect many
Microgrids to form a larger Microgrid network called
PowerParks.
⚫The advantages of this Microgrid structure insures
greaterstabilityand controllability for the Power Parks.

12. Environmental Aspects
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⚫Microgrid encourages the useof the renewable energy
sources.
⚫Large land use impactsareavoided.
⚫CO2 Emissions are reduced.

13. Conventional Grid vs. Microgrid
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⚫Efficiencyof conventional grid isvery low as compared
to Microgrid.
⚫Large amountof energy in the formof heat is wasted in
conventional grid.
⚫Power sources in case of Microgrid (often referred toas
Microsources) are small and are located in close
proximityto load.

14. Advantages & Disadvantages
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⚫ Microgrid Advantages
⚫ A majoradvantageof a Microgrid, is itsability, 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 utilitygrid failure by
reducing the load on thegrid.
⚫ Significantenvironmental benefits made possible by the use
of low orzeroemission generators.

15. Advantages & Disadvantages
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⚫Microgrid Advantages
⚫The useof both electricityand heat permitted by the
close proximityof thegenerator to the user, thereby
increasing theoverall energy efficiency.
⚫Microgrid can act to mitigate theelectricitycosts to its
users bygenerating someorall of itselectricity needs.

16. Advantages & Disadvantages
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⚫Microgrid Disadvantages
⚫ Voltage, frequency and power quality are three main
parameters that must be considered and controlled to
acceptablestandardswhilst the powerand energy balance is
maintained.
⚫ Electrical energy needs to be stored in battery banks thus
requiring morespaceand maintenance.
⚫ Resynchronization with the utilitygrid is difficult.

17. Advantages & Disadvantages
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⚫Microgrid Disadvantages
⚫ Microgrid protection is oneof the most importantchallenges
facing the implementationof Microgrids.
⚫ Issues such as standbychargesand 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
thevoid.

18. Future Directions on Microgrid
Research
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⚫ Toinvestigate full-scale development, field demonstration,
experimental performanceevaluationof frequencyand voltagecontrol
methodsundervariousoperation modes.
⚫ Transition between grid connected and islanded modeson interaction
phenomena between distribution generation and high penetration of
distributed generation.
⚫ Transformationof Microgrid system today into the intelligent,
robust energy delivery system in the future by providing
significantreliability and security benefits.

19. References
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⚫ 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

20. References
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⚫ "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 Answerto Our Energy Crisis"
http://www.fastcompany.com/magazine/137/beyond-the-grid.html
⚫ "Howa Microgrid Works"
http://science.howstuffworks.com/microgrid.htm
⚫ “The Riseof MicroGrid Power Networks"
http://www.sustainablefacility.com/Articles/Feature_Article/58905d08bd629010VgnVC
M100000f932a8c0

21. Thank You
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22. Queries?
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