1. ROLE OF MICRO GRID IN
POWER SECTOR
Sushil Aggarwal
Research Scholar
National Chiao Tung University
Hsinchu, Taiwan (R.O.C.)
2. Micro Grid ….?
Micro means small
Grid means integration of many generation
units and loads.
Hence micro grid means integration of many
small power generation units and loads at
small scale .
Each generation unit called distributed energy
resource (DER) or Distributed generator (DG).
In a single microgrid many DERs(distributed
energy resources) or DGs.
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Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
3. Distributed Energy resources might be solar energy,
wind energy, bio energy, tidal energy, battery storage
resources.
According to MNRE, A “Microgrid” is defined as
renewable energy based Electricity generation with the
capacity of below 10KW.
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Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
4. Why Microgrid ???
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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Non conventional energy resources like coal diesel,
gas etc. degrading day by day.
In last few years, we have invented various
Renewable energy like bio, wind, solar, tidal etc.
We need to take energy from all renewable sources
to overcome the energy demand and avoid energy
crisis.
These resources produces very small amount of
electrical energy that is not possible to take
individually
Hence to integrate all these energy resources
Microgrid invented.
5. Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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According to study by Stanford University top
leading countries that moves completely towards
renewable energy are
Iceland-100 % energy from renewable resources
Sweden- almost 100 % from renewable resources
Cost Rica- almost 100 % from renewable resources
Nicaragua- 90 % from renewable resources
UK, Germany, Uruguay, Denmark, China , Morocco,
USA and Kenya.
6. Components of a Microgrid
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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The microgrid system consists of:
Solar panels/ other RE source
Inverter and batteries
Low-voltage power distribution network
LED lamps, compact fluorescent lamps, fan etc.
for households
7. Some other related information
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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In 1882, Thomas Edison invented the first
Microgrid in The Manhattan, USA.
The aim of India Government is achieve the target
of 500 MW of total capacity over next five years
To set up 10000 units of microgrid by using solar,
wind, and biomass power.
8. Types of Microgrid
On the base of mode of
operation, Microgrid
classified as :-
1. Grid connected mode :-in
this type, microgrid is
connected with main
power grid and supply a
part of load demand.
2. Island mode :- In this type
main grid is not connected
with microgrid, only
microgrid supply all the
load demand.
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Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
9. Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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1.AC Microgrid :- The
working supply is AC
and if any Load and
generation unit working
with DC then the supply
Converted into AC by
using
FACTS devices.
On the basis of power supply,
Microgrid classified as :-
10. Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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2. DC Microgrid :-
The working
supply is DC . If
any Load and
generation is
based on AC then
it is converted into
DC by FACTS
devices.
11. Importance of Microgrid
It provides backup to the grid in case of
emergency.
To make energy independent to a community.
To reduce the cost of electrical energy.
Connect the grid to a very small local resources
that is not to be connected directly to the grid and
many more…..
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Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
13. Objectives of Microgrid control
Structure
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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Voltage and frequency regulation in Both the
modes (Grid connected and island mode)
Proper load sharing and DER coordination
Microgrid resynchronization with main grid
Power flow control between Microgrid and
Main grid
Optimizing the microgrid operating cost
15. Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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Primary Control
Voltage, frequency and circulating current
among DERs of the microgrid including in
primary control
Secondary control
voltage and frequency deviation due to primary
control in between microgrid is under this
control
Territory control
it handles power flow control between main
grid and microgrid, responsible for optimal
oeration
16. Control Techniques of
Microgrid
Centralized control
Decentralized control
Distributed control
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Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
17. 1.Centralized Control Technique
In this type, all the DERs connected by a
central server or controller (MGCC) that is
connected by a communication link like cable.
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Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
18. In this type the individual DER control itself by
Local Controller (LC) and not be connected by
central controller.
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Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
2. Decentralized Control Technique
19. 3. Distributed Control Technique
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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This is same like centralized control
Central controller are absent in this type
Each DERs connected by each other by
communication link
20. Primary Control of Microgrid
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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For primary control there is further two types:-
1. Centralized Control or Active Load Sharing
2. Decentralized Control or Droop based Control
21. Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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Centralized control having some limitations
like
1. Requirement of communication channels
hence cost increased
2. Communication link is not feasible for large
network.
3. Possibility of error if communication channels is
faulty.
Limitations of Centralized
Control
22. Droop based control
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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There are several method based on droop
based:-
1. Conventional Droop control method :-
Droop control module provide amplitude and
phase control signal to PWM and PWM
controller send the control signals to the
inverter .
There is no information sharing between the
DERs hence control s
23. Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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1. Advantages and disadvantages of the
a) Only one control variable hence not satisfy more
than one control variables.
b) Independent, wireless and autonomous control
type
c) Highly inductive effective impedance between VSC
and AC bus.
d) Not beneficial for nonlinear loads, cannot
differentiate harmonics from the current.
e) large droop coefficients tend to reduce stability of
microgrid while small droop coefficients result in
slow responding of inverter.
24. Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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1. Virtual impedance method
2. Adaptive voltage control method
3. Signal injection Method
4. Non Linear load sharing method
5. Adjustable load sharing method
6. Virtual frame transformation method
25. Current Trends
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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General Microgrid replaced by Prosumer
Microgrid
Prosumer mean Consumer cum Producer
By this Microgrid become more smart
Each consumer produce energy and give return
back to the Grid and earn money
A smart energy meter record all the incoming and
outgoing energy data.
In Switzerland, first power project of this kind is
running as pilot project.
In India, in Kerala state first Prosumer based
project.
26. Research Trendz
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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My aim is that each and every household of
our country should be independent in electrical
energy
Energy production should be a profession like
agriculture
Each household can produce energy
We all have to convinced them that energy
production be a good earning source
FREE ENERGY FOR
ALL………..!
27. Software Tool- PSIM
Sushil Aggarwal, Research Scholar, NCTU, Taiwan (R.O.C.)-
30013
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PSIM- Electronics ckt simulation software
Developed by Powersim
Easy to design and implementation
Much faster simulation speed
Automatic C code generation
All Power system circuit component library
Simple and easy than MATLAB
Fault identification is easy.