Icare 2011

IEEE Student Conference on Cognizance of Applied Engineering and Research, ICAER‘11
Light Emitting Polymers
Swapandeep Kaur
ECE, 4th year
UIET, PU
Chandigarh, India
swapanuiet@gmail.com
Abstract— Organic light emitting diode (OLED) display technology
has been grabbing headlines in recent years. Now one form of OLED
displays, LIGHT EMITTING POLYMER (LEP) technology is
rapidly emerging as a serious candidate for next generation flat panel
displays. LEP technology promises thin, light weight emissive
displays with low drive voltage, low power consumption, high
contrast, wide viewing angle, and fast switching times.
One of the main attractions of this technology is the
compatibility of this technology with plastic-substrates and with a
number of printers based fabrication techniques, which offer the
possibility of roll-to-roll processing for cost-effective manufacturing.
LEPs are inexpensive and consume much less power than any
other flat panel display. Their thin form and flexibility allows
devices to be made in any shape. One interesting application of these
displays is electronic paper that can be rolled up like newspaper.
Cambridge Display Technology, the UK, is betting that its light
weight, ultra thin light emitting polymer displays have the right stuff
to finally replace the bulky, space consuming and power-hungry
cathode ray tubes (CRTs) used in television screens and computer
monitors and become the ubiquitous display medium of the 21st
century.
I. INTRODUCTION
Light emitting polymers or polymer light emitting diodes
discovered by Friend et al in 1990 has been found superior
than other displays like, liquid crystal displays (LCDs)
vacuum fluorescence displays and electro luminescence
displays. Though not commercialised yet, these based
have proved to be a mile stone in the field of flat panel
displays. Research in LEP is underway in Cambridge
Display Technology Ltd (CDT), the UK.
In the last decade, several other display
contenders such as plasma and field emission displays
were hailed as the solution to the pervasive display. Like
LCD they suited certain niche applications, but failed to
meet broad demands of the computer industry. Today
the trend is towards the non_crt flat panel displays. As
LEDs are inexpensive devices these can be extremely
handy in constructing flat panel displays. The idea was to
combine the characteristics of a CRT with the performance
of an LCD and added design benefits of formability and
low power. Cambridge Display Technology Ltd is
developing a display medium with exactly these
characteristics. The technology uses a light-emitting
polymer (LEP) that costs much less to manufacture and
run than CRTs because the active material used is plastic.
II. WHAT IS LEP?
LEP is a polymer that emits light when a voltage is
applied to it. The structure comprises a thin film semi
conducting polymer sandwiched between two electrodes
namely anode and cathode. When electrons and holes are
injected from the electrodes, the recombination of these
charge carriers takes place, which leads to emission of
light that escape through glass substrate.
The ban gap that is energy difference between
valence band and conduction band of the semi conducting
polymer determines the wave length that is colour of the
emitted light.
The first polymer LEPs used poly phinylene
vinylene (PPV) as the emitting layer. Since 1990, a
number of polymers have been shown to emit light under
the application of an electric field; the property is called
the electro luminescence (EL)
PPV and its derivatives, including poly
thiophenes, poly pyridines, poly phenylenes and
copolymers are still the most commonly used materials.
Efforts are on to improve stability, lifetime
and efficiency of polymer devices by modifying their
configuration.
III. CHEMISTRY BEHIND LEP
LEPs are constructed from a special class of polymers
called conjugated polymers. Plastic materials with
metallic and semiconductor characteristics are called
conjugated polymers. These polymers posses delocalised
pi electrons along the backbone, whose mobility shows
properties of semiconductors. Also this gives it the ability
to support positive and negative charge carriers with high
mobility along the polymer chain.
The charge transport mechanism in
conjugated polymers is different from traditional

inorganic semiconductors. The amorphous chain
morphology results in inhomogeneous broadening of the
energies of the chain segments and leads to hopping type
transport.
Conjugated polymers have already found
application as conductor in battery electrodes, transparent
conductive coatings, capacitor electrolytes and through
hole platting in PCB’s. There are fast displaying
traditional materials such as natural polymers etc owing to
better physical and mechanical properties and amenability
to various processes.
IV. BASIC STRUCTURE AND WORKING
An LEP display solely consists of the polymer material
manufactured on a substrate of glass or plastic and doesn’t
require additional elements like polarizers that are typical
of LCDs. LEP emits light as a function of its electrical
operation.
The basic LEP consists of a stack of thin
organic polymer layers sandwiched between a transport
anode and a metallic cathode. Figure shows the basic
structure. The indium-tin-oxide (ITO) coated glass is
coated with a polymer. On the top of it, there is a metal
electrode of Al, Li, Mg or Ag. When a bias voltage is
applied, holes and electrons move into the polymer.
These moving holes and electrons combine together to
form hole-electron pairs known as “excitons’. These
excitons are in excited state and go back to their initial
state by emitting energy.
When this energy drop occurs light comes out
from the device. This phenomenon is called
electroluminescence. It is shown in figure 2&3. The
greater the difference in energy between the hole and the
electron, the higher the frequency of the emitted light.
V. TYPES OF DISPLAYS
The LEP displays are two types, namely, passive matrix
and active matrix.
To drive a passive matrix display, the current
is passed through select pixels by applying a voltage to the
drivers attached to the corresponding rows and columns.
These schemes pattern the anode and cathode into
perpendicular rows and columns and apply a data signal to
the columns while addressing the sequentially. As the
number of rows in the display increases, each pixel must
be red brightness by a factor of the number or row times
the desired brightness, which can exceed 20000cd/m2.the
current required to achieve this brightness, levels limits
this architecture to relatively small screen sizes. Philips
Flat Display systems (Sunnyvale, CA) and DuPont
Displays have demonstrated full-colour passive matrix
displays.
In active matrix architecture, thin film
polysilicon transistors on the substrate address each pixel
individually. Active matrix displays are not limited by
current consideration. Seiko-Epson, Toshiba (Tokyo,
Japan), and Samsung (Seoul, Korea) have now
demonstrated full colour active matrix displays. One
exciting possibility is that polymer transistors, which can
be manufactured by techniques similar to those used for
LEP patterning, could be used to drive an LEP display.
Such an approach would potentially lend itself to roll-to-
roll processing on flexible substrates.
VI. MANUFACTURING
In order to manufacture the polymer two techniques are
used.
Spin coating process
This technique involves spinning a disk, that
is glass substrate at a fixed angular velocity and letting a
small amount of polymer solution to drop on the top of the
disk. It is shown in the figure. Spin coating machine used
has a few thousands rotations per minute.
The robot pours the plastic over the rotating
plate, which in turn, evenly spreads the polymer on the
plate. This results in an extremely fine layer of the
polymer having a thickness of 100 nanometres. Once the
polymer is evenly spread, it is abaked in an oven to
evaporate any remnant liquid.

Printer based technique
LEPs can be patterned using a wide variety of printing
techniques. The most advanced is ink-jet printing (figure).
Resolution as high as 360 dpi have been demonstrated, and the
approach are scalable to large-screen displays. Printing
promises much lower manufacturing cost.
Printer based technique
VII. TYPES OF LEPS
1)Flexible organic LEPs
They are built on flexible substrates instead of
glass substrates. These materials provide the ability to
conform, bend or roll a display into any shape. So these
find application on helmet face shields, military uniforms,
shirtsleeves and automotive windshields.
2)Stacked organic LEPs
They use pixel architecture and offers high-
definition display resolution and true-colour quality for
the next generations display applications. With this type,
each pixel emits the desired colour and thus is perceived
correctly, no matter what size it is and from where it is
viewed.
Figure SOLEP
3)Transparent organic LEPs
The employ an innovative transparent contact
to achieve an enhanced display. They can be top, bottom
or both top and bottom emitting (transparent). Bi-
directional LEPs will provide two independent displays
emitting from opposite faces of the display. With portable
products shrinking and desired information content
expanding, transparent LEPs are a great way to double the
display area for the same display size.
TOLED STRUCTURE
VIII. ADVANTAGES
Require only 3.3 volts and have lifetime of more
than 30,000 hours
Greater power efficiency than all other flat panel
displays
No directional or blurring effects

Can be viewed at any angle
Glare free view up to 160 degree
Cost much less to manufacture and run than CRTs,
because the active material used is plastic
Can scale from tiny devices millimeters in
dimension t high definition device up to 5.1 meters
in diameter.
Fast switching speed, that is 1000 times faster than
LCDs.
Higher luminescence efficiency. Due to high
refractive index of the polymer, only a small
fraction of the light generated in the polymer layer
escapes the film.
They don’t additional elements like the backlights,
filters and polarizers that are typical of LCDs.
Heads-up instrumentation for cars
Lightweight wrist watches
High definition televisions.
Roll-up daily refreshable electronic newspapers
Automobile light systems without bulbs
Windows/wall/partitions that double as computer screens
Military uniforms
Aircraft cockpit instrumentation panel a lot of others
Manufactures like DuPont Displays, OSRAM, Philips, Seiko-
Epson, Ritek and many others have already started producing
LEP displays and will be soon available in the market.
1. Aging of LEP
IX. LIMITATIONS
XI. FUTURE DEVELOPMENTS
High efficiency displays running on low power and
economical to manufacture will find many uses in the
consumer electronics field. Bright, clear screens filled with
One of the major barriers to the commercial
development of LEP is its useful lifetime. Even under
ideal conditions, the light intensity gradually decreases
and some discrete regions become totally dark. This
phenomenon is the ‘aging of LEP’.
One method to reduce or stop aging is that the
final soldering of the displays is to be done in an airtight
environment because as soon as the LEP molecules come
in contact with oxygen, these would disintegrate. The
solution was to do the final soldering in glass jar filled
nitrogen. The enclosure protects the device from
impurities and provides a higher degree of efficiency by
giving the screen an estimated life span of 30,000 working
hours.
2. Space charge effect
The effect of space charge on the voltage-
current characteristics and current-voltage characteristics
becomes more pronounced when the difference in the
electron hole nobilities is increased. Consequences of
space charge include lowering of the electric fields near
the contacts and therefore suppression of the injected
tunnel currents and strongly asymmetric recombination
profiles for unequal mobility thereby decreasing the
luminescence and hence decreases the efficiency.
Research is underway to overcome this barrier
Even though these limitations are there LEPs
found to be superior to other flat panel displays like LCD,
FED (field emission display) and etc.
information and entertainment data of all sorts may make our
lives easier, happier and safer.
Demands for information on the move could drive the
development of 'wearable' displays, with interactive features.
Eye catching packaging with changing information content at
point of sale would give many brand owners competitive edge.
XII. CONCLUSION
LEPs are promising, low cost solutions for today’s flat panel
displays. Although not commercialised yet, these replace
bulky and heavy CRT displays in the near future. However
research is underway to improve the efficiency and lifetime of
the polymer displays.
A panel of industry leaders predicted that LEP technology
would storm the market in the near few years and we will find
LEP in every sphere of life.
LEP technology is now set to change the products we
use to view the world.
REFERENCES
[1] Electronics for you April 2002(pgs,90-93)
[2] Electronics for you June 2003 (99-102)
[3] IEEE spectrum June 2003 (26-29)
[4] Hindu(newspaper) July 31 2003 (16)
[5] www.iec.org
[6] www.cdtltd.co.uk
[7] www.cknow/ckinfo/aco-I/lep-Istm
[8] www.research.philips.com
[9] www.covion.com

MAC filtering in wireless G Router
Er.Atinderpal singh1
,Er.Kawalpreet Singh2
, Er.Manjot Singh 3
1
M.Tech student, Department of Electronics Technology GNDU Amritsar,
2
Assistant proff. NWIET Moga, 3
M.Tech student, SBSCET, ferozepur,
atinder_mehal@yahoo.com1
, kawal.engg@gmail.com2
, manjot85@gmail.com3
Abstract
Wireless 802.11g Router lets you share files and a
broadband Internet connection among your computers,
without cables. In this paper we have studied the wireless
G router. We have also studied the MAC filtering in G
Routers. The MAC Address Filtering in G Router and
MAC spoofing has been also studied.
Introduction
A wireless router is a network device that enables
you connect several computers to the Internet
without using cables, rather by using wireless
access points, or WLAN. Some of the reason we go
wireless networking include freedom and
affordability. The IEEE 802.11 standard permits
devices to establish either peer-to-peer (P2P)
networks or networks based on fixed wireless
routers with which mobile nodes can communicate.
Hence, the standard defines two basic network
topologies: the infrastructure network and the ad
hoc network [1]. A wireless router allows the
broadcasting, forwarding, coordination,
synchronisation, and bridging of packets. The area
covered by a wireless router is technically referred
to as a Basic Service Set (BSS). A Service Set
Identifier (SSID) identifies every BSS, and is
ultimately the identification given to devices within
a specific cell to enable wireless communication.
Wireless 802.11g Router lets you share files and a
broadband Internet connection among your
computers, without cables. It makes it easier than
ever to access networked peripherals, such as hard
drives, printers, CD-ROMs, and DVDs. Featuring
Wi-Fi Certified 802.11g technology, Router speeds
data among your computers faster at up to 54Mbps.
The Wireless 802.11g Router uses the 802.11g
2.4GHz wireless standard to offer you a wider
wireless range over the 802.11b Wi-Fi standard.
802.11g technology is not only
backwardcompatible with 802.11b, it works in
mixed networking environments so you can
implement faster wirelesstechnologies in
combination with existing 802.11b equipment. An
integrated, 4-port 10/100Base-T Ethernet switch
lets you connect wired computers on your network
as well. Now you can securely transfer fi les around
the home or office—enjoying freedom from cables
along with all the advantages of a wired network.
Wireless Standards for routers are IEEE 802.11g,
IEEE 802.11b, IEEE 802.3u 100Base-Tx, IEEE
802.3 10Base-Tx. For Security Practically we can
use WPA, 64-bit WEP, 128-bit encryption etc. The
system requirements are broadband Internet
connection such as a DSL or cable modem with
RJ45 (Ethernet) connection, At least one computer
with an installed network interface adapter, TCP/IP
networking protocol installed on each computer,
RJ45 Ethernet networking cable, Internet browser.
The 802.11b standard was approved in July 1999,
roughly two years after the introduction of the
initial 802.11 standard. Like its predecessor 802.11,
802.11b also operates in 2.4 GHz ISM band, which
provides relatively good range and wall penetration
capabilities in indoor environments. The 802.11g
standard was approved in June 2003. Just like
802.11b it also operates in the ISM band, utilizes
the same OFDM modulation used in the 802.11a
standard, and provides a maximum data rate of 54
Mbps
Wireless Technologies / Standards
The IEEE 802.11 standards specify two operating
modes: infrastructure mode and ad hoc mode.
Infrastructure mode is used to connect computers
with wireless network adapters to an existing wired
network with the help from wireless router or
access point, while Ad hoc mode is used to connect
wireless clients directly together, without the need
for a wireless router or access point. IEEE 802.11g
provides good throughput as well as avoids
collision as compared to IEEE 802.11b. The 802.11
standard establishes and defines the mode of
channelling the unlicensed radio frequency bands
in WLANs.
802.11a
The IEEE 802.11a adopted the OFDM modulation
technique and uses the 5 GHz band. The 802.11a
devices operating in the 5 GHz band are less likely
to experience interference than devices that operate
in the 2.4 GHz band because there are fewer
consumer devices that use the 5 GHz band. Also,
higher frequencies allow for the use of smaller
antennas. The advantages are i.e, speed uses up to
up to 54 Mbps, has the fastest transmission speed,
allows for more simultaneous users, uses the 5 GHz
frequency, which limits interference from other

devices. The few disadvantages of using the 5 GHz
band are (a) Higher frequency radio waves are
more easily absorbed by obstacles such as walls,
making 802.11a susceptible to poor performance
due to obstructions, (b) Higher frequency band has
slightly poorer range than either 802.11b or g.
Also, some countries, including Russia, do not
permit the use of the 5 GHz band, which may
continue to curtail its deployment, (3) It is not
compatible with 802.11b network adapters, routers,
and access points
802.11b
This was the first and, until recently, the most
common wireless variant used. With transmission
speeds of just 11Mbits/sec it is also the slowest. It
also used the 40bit Wireless Equivalency Privacy
(WEP) security protocol, which was found to have
a number of deficiencies. A newer version of this,
802.11b+ maintains speeds to 22Mbits/sec. The
advantages are its speed 11megabits per seconds,
costs less, has the best signal range. The
disadvantages are the transmission speed is slow,
uses the 2.4 gigahertz (GHz) of frequency the same
as some house hold items like cordless, micro
waves ovens etc, and it provides access to few
users simultaneously.
802.11g
This is the most recent and popular in use now,
offering more respectable data transfer speeds of up
to 54Mbits/sec, but its speed are much lower. It
also uses an upgraded form of Wi-Fi Protected
Access (WPA) security protocol. The advantages
are its speed uses Up to 54 Mbps, has a
transmission speed comparable to 802.11a under
optimal conditions i.e, (a) Allows for more
simultaneous users (b) Has the best signal range
and is not easily obstructed, (c) it is compatible
with 802.11b network adapters, routers, and access
points. The disadvantages are it uses the 2.4 GHz
frequency so it has the same interference problems
as 802.11b and it costs more than 802.11b.
802.11n
The 802.11n draft standard is intended to improve
wireless data rates and range without requiring
additional power or radio frequency band
allocation. The 802.11n uses multiple radios and
antennae at endpoints, each broadcasting on the
same frequency to establish multiple streams. The
multiple input/multiple output technology splits a
high data-rate stream into multiple lower rate
streams and broadcasts them at the same time over
the available radios and antennae. This allows for a
speculative maximum data rate of 248 Mb/s using
two streams.
The infrastructure mode bridges a WLAN with a
wired Ethernet LAN, in which all wireless devices
communicate with a central base station (a wireless
router). A wireless router allows the broadcasting,
forwarding, coordination, synchronisation, and
bridging of packets. The area covered by a wireless
router is technically referred to as a Basic Service
Set (BSS). A Service Set Identifier (SSID)
identifies every BSS, and is ultimately the
identification given to devices within a specific cell
to enable wireless communication. Many wireless
routers support multiple SSIDs. Most researches
with regard to wireless routers have been focused
on the areas of bandwidth, performance, and
security. From the bandwidth point of view, several
techniques have been introduced in order to
maximize it, which includes the modification of
protocols [2], effective channel allocations [3], load
balancing , and maximizing parameters between
physical layer and IEEE 802.11 [4]. From the
performance point of view, there were several
attempts, such as scheduling the resources of
wireless router by monitoring delay and packet loss
[5], developing multi-layered IPsec based on
utilization of IPsec [6], reducing loss ratio and
transportation time by arranging the buffer size [7],
and introducing middleware for performance
improvement [8]. Finally from the security point of
view, there is an algorithm which isolates the
problem nodes by new network layer mechanism
[9], or finds the weakness of the wireless networks
based on VPN and solutions [10].
Wireless G router
The Wireless-G Broadband Router has been
specifically designed for use with both your
802.11b and 802.11g products. Now, products
using these standards can communicate with each
other. The Wireless-G Broadband Router is
compatible with all 802.11b and 802.11g adapters,
such as the notebook adapters for your laptop
computers, PCI adapters for your desktop PCs, and
USB adapters when you want to enjoy USB
connectivity. The Router will also communicate
with the Wireless-G PrintServer, as well as 802.11b
and 802.11g wireless Ethernet bridges. When you
wish to connect your wireless network with your
wired network, you can use the Wireless-G
Broadband Router’s four Ethernet ports. Once your
computers are connected to the Router and the
Internet, they can communicate with each other
too, sharing a printer, digital music, picture and
document files, and multiplayer or on-line games.
To protect your data and privacy, the Wireless-G
Broadband Router can encode all wireless
transmissions with WEP or high security WPA
Personal encryption. The Router can serve as a
DHCP Server, has a powerful SPI firewall to

protect your PCs against intruders and most known
Internet attacks, and supports VPN pass-through.
MAC FILTERING
Most Wi-Fi access points and routers ship with a
feature called hardware or MAC address filtering.
This feature is normally turned "off" by the
manufacturer, because it requires a bit of effort to
set up properly. However, to improve the security
of your Wi-Fi LAN (WLAN), strongly consider
enabling and using MAC address filtering. With
MAC filtering you can specify precisely which
computers can connect to your wireless network
and which cannot. This way even if someone
knows your hidden SSID and security key they will
not be able to connect to your wireless network if
you don't want them to. This is a great form of
additional security.
Media Access Control (MAC) filtering is a
technique used to control access to network
resources. It describes filtering down at the Data
Link Layer (OSI layer 2). With Ethernet, a filtering
policy on network equipment can permit or deny
access to the network based on the theoretically
unique Ethernet 48bit address. MAC address
filtering is not a foolproof way to secure your
wireless network and should not be considered a
substitute for wireless encryption. It's an additional
layer of security for your wireless network and
added peace of mind for you and your family.
Without MAC address filtering, any wireless client
can join (authenticate with) a Wi-Fi network if they
know the network name (also called the SSID) and
perhaps a few other security parameters like
encryption keys. When MAC address filtering is
enabled, however, the access point or router
performs an additional check on a different
parameter. Obviously the more checks that are
made, the greater the likelihood of preventing
network break-ins.
A MAC address is a unique hexadecimal number
which has been burned into a networking devices
circuit board by the manufacturer. In most cases of
network devices, MAC is invisible without the use
of a command called "ipconfig". By going to your
command prompt and typing in "ipconfig /all"
(Without the quotes) you'll find your computers
"physical address". The physical address is your
MAC address and usually looks something like
this: 00-0F-1F-D5-6A-37. Theoretically no two
Mac addresses in the world are alike. For added
security, you can set up a list of MAC addresses
(unique client identifiers) that are allowed access to
your network. Every computer has its own MAC
address. Simply enter these MAC addresses into a
list using the Web-Based Advanced User Interface
and you can control access toyour network.
Now we will discuss about the mechanism of MAC
filtering. We can limit access to your home/office
network to increase the security of the information
stored on it. MAC address filtering allows you to
specify the computers that can access the network.
Each computer is assigned a MAC address. We can
use this MAC address to specify the only
computers allowed to connect to our wireless
network. The client with approved MAC address
from the access point will only be allowed to
access your network and other clients will be
denied. Following is the step by step procedure of
MAC Address Filtering in G Router (LINKSYS
WAP54G) also shown in figure 1 and 2.
1. In the LINKSYS G Router go to the Setup
-> Basic Setup Option. Give some name to
the Access Point as shown or do not
change the default name.
2. In the Advanced Option the default
settings of MAC Address Filtering is
Disabled .
3. To Enable MAC Filtering select the
Enable option from the box.
4. After Enabling MAC Filtering, a WLAN
administrator can either prevent or permit
the list of PC’s to access the wireless
network.
5. A Wlan administrator should enter the
MAC address of the clients in the given
columns.
6. Enter the MAC address in the format as
shown below and select the option
whether to permit or prevent the listed
PC’s from accessing the wireless network.
7. Save the changes and only those
computers will be allowed to access the
network which are included in the list.
Figure 1. MAC Address Filtering in G Router (LINKSYS
WAP54G)

Figure 2. MAC Address Filtering in G Router (LINKSYS
WAP54G)
The advantages of MAC Filtering are (a) MAC
filtering has one advantage over all other security
methods. As it does not involve any data
encryption, MAC filtering has no packet overhead
and thus does not have any performance impact on
network traffic or bandwidth. The average transfer
rate of a file with MAC filtering is more than with
64-bit WEP encryption due to no packet overhead
involved in it. Of course, 128-bit WEP encryption
will show even lower transfer rates than 64-bit
WEP, due to the larger packet overhead. So, MAC
filtering is definitely good for people who are
interested in maximizing network throughput. (b)
In MAC filtering there is no attachment cost to
devices that connect to the network. The policy is
set on a router or switch, and the equipment
attached either is permitted or it is not. The person
attaching the equipment has nothing to do. The
disadvantages (a) MAC filtering is that it is easy to
spoof. Because of the broadcast nature of Ethernet,
and particularly wireless Ethernet, an advisory can
sit on the wire and just listen to traffic to and from
permitted MAC addresses. Then, the advisory can
change his MAC address to a permitted one and in
most cases obtain access to the network, (b) The
need to discover the MAC address of every client’s
adapter and enter it into the AP’s settings fields. As
a one-off task, it might take you half an hour from
start to finish for say, half a dozen client machines.
However, if a PC Card gets lost, you buy new ones,
or you add or upgrade an AP, it can make for a lot
of extra tedious typing.
MAC Spoofing
MAC Spoofing is a technique by which a hacker
assumes your role as a legitimate user over a
wireless network. It actually doesn't require any
hacking skills. Anyone can do it with tools that can
alter the MAC address on your wireless adaptor. A
MAC-spoofing attacker attempts to break into a
LAN by assuming the MAC identity of an
authorized computer station on the LAN. MAC
address spoofing in this context relates to an
attacker altering the manufacturer-assigned MAC
address to a value that facilitates invading a
LAN[12]. Discussing about MAC Spoofing Tools,
free software that can intercept MAC addresses and
spoof them, like Nets tumbler, are readily available.
Libnet, a high-level API (toolkit), designed and
maintained primarily by Mike D. Schiffman.
―Libnet is a reasonably small programming library,
written mainly in C, providing a high-level,
standard portable interface to low-level network
packet shaping, handling and injection primitives ‖.
It works by providing spoofing directly on the LAN
by construction and packaging of network packets
with the spoofed MAC address. Cain, an all around
intrusion device, is also used as a MAC spoofing
tool. Its default MAC spoof address is simply
00:11:22:33:44:55, mostly because this address is
not supposed to exist in a network. Therefore, using
MAC filtering on its own can be a security risk.
The methods to prevent MAC spoofing are (1) To
prevent MAC address spoofing or computer
identity theft, one needs knowledge of the two
schemes involved in preventing MAC spoofing
attacks[13]. One scheme is to detect MAC
spoofing, the other is to harden the system, access
points, or individual machines. A quick way to
detect if a suspected MAC address is being
compromised is to run RARP (Reverse Address
Resolution Protocol) against it. RARP maps a
MAC address to an IP Address.
As one MAC address should map to a single IP
Address, Reverse ARP should return one IP
address for one network device, so if multiple IP
addresses return, one has evidence to pursue further
investigation, (2) Whenever ARP packets arrive it
should not check the MAC Address for the OS, its
should retrieve it directly from LAN card or when
ever ARP packets arrive it should compare the
MAC Address from OS to NIC and if it doesn’t
match it should delete the entry from OS or from
registry, (3) MAC Address is stored in OS
whenever MAC Address is required it is retrieve
from Operating System if we want to prevent MAC
Address to be spoofed then whenever we require
MAC Address we must retrieve it directly from
NIC, (4) There are softwares that can prevent MAC
spoofing. One of them is Sygate Firewall, which
has an ―Anti-MAC Spoofing” feature. All you need
to do was to activate the feature and you are
protected against MAC spoofing.
CONCLUSION
Wireless 802.11g Router plays important role in
share files and a broadband Internet connection
among your computers, with wireless connection. It
makes it easier than ever to access networked
peripherals, such as hard drives, printers, CD-
ROMs, and DVDs. We have discussed about

wirless routers and standards. In this paper we have
studied G Router with MAC filtering. We have also
studied MAC spoofing. The use of MAC filtering
with G Router has one advantage over all other
security methods. As it does not involve any data
encryption, MAC filtering has no packet overhead
and thus does not have any performance impact on
network traffic or bandwidth. MAC address
filtering is a very simple yet effective way to secure
your wireless network.
References
[1] Tan, T.K. Bing, Benny. World Wide Wi-Fi.
Technological Trends and Business Strategies John
Wiley & Sons, 2003, ch. 1, pp 20-15.
[2] K. Ghaboosi and B. Khalaj, "A novel transport
agent for wireless routers to improve TCP and UDP
performance over wireless links", IEEE 16th
International Symposium on Personal, Indoor and
Mobile Radio Communications, pp. 2201-2205,
Sept. 2005.
[3] M. Alicherry, R. Bhatia, and L. Li, "Joint
Channel Assignment and Routing for Throughput
Optimization in Multiradio Wireless Mesh
Networks", IEEE Journal on Selected Areas in
Communications, Vol. 24, No. 11, pp. 1960-1971,
Nov. 2006.
[4] W. Hneiti and N. Ajlouni, "Performance
Enhancement of Wireless Local Area Networks",
2nd Information and Communication
Technologies, pp. 2400-2404, April 2006.
[5] C. Oottamakorn and D. Bushmitch, "Resource
management and scheduling for the QoS-capable
home network wireless access point", 1st IEEE
Consumer Communications and Networking
Conference, pp. 7-12, Jan. 2004.
[6] Yongguang Zhang, "A multilayer IP security
protocol for TCP performance enhancement in
wireless networks", IEEE Journal on Selected
Areas in Communications, Vol. 22, No. 4, pp. 767-
776, May. 2004.
[7] N. Gulpinar, P. Harrison, B. Rustem, and L.
Pau, "Performance Optimzation of Mean Response
time in a Tandem Router Network with Batch
Arrivals", 10th IEEE/IFIP Network Operation and
Management Symposium, pp. 1-4, 2006.
[8] E. Wong, A. Chan, and H. Leong, "Xstream: a
middleware for streaming XML contents over
wireless environments", IEEE Transactions on
Software Engineering, Vol. 30, No. 12, pp. 918-
935, Dec. 2004.
[9] R. Ramanujan, S. Kudige, and T. Nguyen,
"Techniques for intrusion resistant ad hoc routing
algorithm (TIARA)", Proceedings DARPA
Information Survivability Conference and
Exposition, pp. 90-100, April 2003.
[10] L. Fazal, S. Ganu, M. Kappes, A.
Krishnakumar, and P. Krishnan, "Tackling security
vulnerabilities in VPN-based wireless
deployments", IEEE International Conference on
Communications, pp. 100-104, June 2004.
[12] MAC Spoofing – An Introduction by Edgar
D Cardenas (23 August 2003 )
[13] International Journal of Recent Trends in
Engineering Vol 2 ; MAC Spoofing and its
Counter- Measures (November 2009)

Magnetorheological Fluids and its
Applications
Vikas Kumar
University Institute of Engineering and Technology, Panjab University
Chandigarh (UT), INDIA vikas.kumar007r@gmail.com
Abstract- This paper is about a magnetorhelogical fluid
(MR fluid) which is a type of smart fluid in a carrier
fluid, usually a type of oil. MR fluids are suspensions of
solid in liquid whose properties change drastically when
exposed to magnetic field. The term
“magnetorhelogical” comes from this effect.
Rheology is a branch of mechanics that focuses on the
relationship between force and the way a material
change shape. When MR fluid subjected to a magnetic
field, the fluid greatly increases its apparent viscosity, to
a point of becoming a viscoelastic solid.
When exposed to a magnetic field, the particles in
magnetorheological fluid align along field lines.
I. INTRODUCTION
Functional fluids change their rheological
characteristics when an external field like an electric
or magnetic field is applied to them. Examples of
functional fluids are electrorheological (ER) fluids
magnetic fluids and magnetorheological (MR) fluids.
ER fluids use an electric field, while magnetic and
MR fluids use a magnetic field.
An MR fluid is a non-colloidal solution containing
polar particles that are several micrometers in
diameter. Basically suspension or non colloidal
solution is those heterogeneous fluids containing
solid particles that are sufficiently large for
sedimentation settle down if left undisturbed. MR
fluid is different than the Ferro fluid which has
smaller particles. MR fluids are too dense for
Brownian moment (it is a random drifting of a
particles suspended in a liquid) to keep them suspend.
Ferro fluid particles are of nanoparticles that are
suspended by a Brownian motion and will not settle
under normal condition. As a result both have
different application.
The essential characteristic of these fluids is their
ability to reversibly change from a free flowing fluid
to a quasi solid having proper yield strength when
exposed to magnetic field.
A. Chemical Composition
A typical MR fluid consists of 20% to 40% by
volume of relatively pure, soft iron particles,
typically 3 to 5 microns suspended in a carrier liquid
such as mineral oil, synthetic oil, water or glycol. A
variety of additive also added to discourage or
neglecting gravitational settings and promote particle
suspension, enhance lubricity, modify viscosity, and
inhibit wear.
B. Physical Properties
MR fluids are made from iron particles exhibit
maximum yield strengths of 30 to 90 kPa for applied
magnetic fields of 150 to 250 kA/m. MR fluids are
not highly sensitive to moisture and contaminants or
foreign particles during manufacturing and use
further because the magnetic polarization mechanism
is not affected by the surface chemistry of surfactants
and additives. The ultimate strength of the MR fluid
depends on the square of the saturation magnetization
of the suspended particles. Due to it the MR fluids
posses anisotropic properties.
C. Material Behavior
MR fluids are the smart fluids as that posse’s low
viscosity in the absence of a magnetic field and act as
a quasi-solid in the presence of magnetic field. MR
fluids posse’s properties of a solid material in ON
state or activated state and have a yield point above
which shearing occurs. Yield stress is directly
dependent on the magnetic field applied to fluid. As
the fluid reaches its maximum yield point then after it
the magnetic field has no effect on the fluid as fluid
reaches magnetic saturation.
MR fluids behavior is similar to the behavior of
Bingham plastic. Bingham plastic is a pseudo plastic
act as a solid up to a certain yield stress or a threshold
value of a yield stress, after which it flow as a fluid
e.g. honey, toothpaste, blood etc.

However, a MR fluid does not act as a Bingham
plastic i.e. characteristics of both are not similar.
Below a yield stress the fluid behaves as a
viscoelastic material, dependent on the magnetic field
intensity. These fluids are also subjected to shear
thinning, where viscosity above yield decreases with
increase in shear rate. Further in OFF state these
fluids act as a non-Newtonian and temperature
dependent.
So our MR fluid behavior becomes:
Where τ = shear stress; τy = yield stress; H =
Magnetic field intensity η = Newtonian viscosity;
is the velocity gradient in the z-direction.
D. Characteristics Of Good MR Fluid
It is a basic question which arises that what makes a
good MR fluid. Basically a fluid that have:
a. High yield strength
b. Slow settling capacity
Yield strength of the MR fluid can be increased by
compressing in direction of magnetic field.
Similarly, settling capacity can be slowed by adding
some surfactants in the MR fluids. Surfactants such
as oleic acid, tetramethylammonium hydroxid, citric
acid etc
II. WORKING
MR fluid is consisting of iron particles which are
randomly distributed in a fluid. As shown in figure
below:
When a magnetic field is applied to this fluid the
particles are no more in a randomized manner they
align themselves in a direction of magnetic field. Due
to this alignment of particles a chains of particles is
formed which restrict the fluid to flow. This effect
last so long till the magnetic field is in ON state. As
shown below in figure below:
These chains restrict the fluid flows and posses a
property of quasi-solid having some yield strength. In
designing this type of fluid it is important to ensure
that the lines of flux are perpendicular to the direction
of motion to be restricted.
III. LIMITATIONS
MR fluids have many applications although they
have certain limitations:
a. High density: The iron particles are present
in the MR fluids due to which they are
heavy.
b. High quality fluids are expensive.
c. Settling of Ferro particles.
d. Installation is costly.
IV. MODES OF OPERATIONS
There are basically 3 modes on which the
applications of MR fluids based upon these are:
A. Flow Mode
This mode is the mode when flow of liquid is
happening between the plates due to pressure
gradient in stationary plates.

This mode is used in dampers and shock absorbers by
controlling the movement of fluid flow through the
plates by varying magnetic intensity.
B. Shear Mode
This mode is the mode takes place when fluid
between plates moves relative to one other. Shear
mode is used in clutches and break in places where
rotational motion must be controlled.
C. Squeeze-Flow Mode
This mode is the mode takes place when the fluid
between plates moving in the direction perpendicular
to their planes. This mode is suitable for applications
controlling small, millimeter–order displacement but
involving large forces.
V. APPLICATIONS
Due to the miracle behavior of MR fluid it has wide
application in many fields. MR fluids property of
acting like quasi-solid make them very useful in
today’s world.
A. Magnetorheological Dampers
The MR fluid in flow mode is used in
magnetorheological dampers. As motion control
systems become more refined, vibration
characteristics become more to a system as overall
design and functionality. MR fluids find a variety of
application in all the vibration control systems. There
are different field in which these MR fluid dampers
are used:
a. Automobile Suspensions
It is widely used in automobile suspensions. Shock
absorbers of vehicle’s suspension are filled with MR
fluids instead of plain oil and whole arrangement
surrounded by with an electromagnet. Due to use of
this we can varies the viscosity of fluid and damping
provided by the shock absorber. For e.g. General
Motors has developed this technology for automotive
applications. This improves ride and handling. These
dampers are under development for use in military
and commercial helicopter cockpit seats, as safety
devices in the event of crash.
b. Human Prosthesis
MR fluids are used in semi-active human prosthetic
legs. These provide dampers in the prosthetic legs
decrease the shock delivered to the patients leg when
jumping, result in increased mobility and agility for
the patient.
c. Washing Machine
In washing machine there is unwanted vibratory
motion in its spin cycle. MR damping can correct this
problem of vibrations and noise.
d. Seismic Dampers
MR fluids are used in the construction industry into
the structural engineering of buildings and bridges.
System is relatively inexpensive, needs little
maintenance and requires very low power to operate.
A damping system utilizes MR fluid dampers work
similarly to an automotive shock absorber, protecting
structure from earthquake and windstorms. These are
also helpful in protecting a building or bridge during
a severe earthquake. MR dampers are currently being
used on the Dongting Bridge in China below.

B. Military and Defence
US Army Research Office is currently funding
research into using MR fluid to enhance body armor.
In addition they use MR technology in vehicles
dynamic MR shock absorbers and dampers.
Since magnets are large enough to affect entire suit
would be heavy and impractical to carry around,
researchers propose creating tiny circuits running
throughout the armor.
Without current flowing through the wires, the armor
would remains soft and flexible. But at the flip of
switch current flowing and creating a magnetic field
in the process. The field cause the armor stiffens and
harden instantly. Switching off would stop the
current flowing and armor would become flexible
again.
C. Optics
MR fluid based optical polishing method has proven
to be highly precise. It was used in the construction
of Hubble Space Telescope’s corrective lens.
D. Robo Blood
Astronauts onboard the International Space Station
are studying strange fluids that might one day flow in
the veins of robots. MR fluids are liquids that harden
or change shape when they feel a magnetic field.
The nervous system of robots further uses MR fluids
to move joints and limbs.
VI. ADVANCEMENTS IN MR FLUID
TECHNOLOGY
Recent researches on MR fluid have made
advancements in this technology. In addition to cost
sensitive applications such as washing machines, MR
fluid dampers are used in rotary brakes for exercise
equipments and pneumatic systems. They are also
used in heavy duty truck suspensions, in adjustable
linear shock absorbers for racing cars. MR fluid
durability and life have been found to be more
significant barriers to commercial success than yield
strength and stability. Challenges for future MR fluid
development are fluids that operate in the high shear
regime, thus MR fluids are considered as a better way
of controlling vibrations.
VII. ACKNOWLEDGEMENT
I heartily thanks to my friends who motivate me and
help me in this review paper, due to which my paper
has completed. I give special thanks to my roommate
Amit Dixit for his help.
VIII. REFERENCES
[1] http://en.wikipedia.org/wiki/Viscosity
[2] http://www.sensorsmag.com/sensors/electric-
magnetic/controlling-vibration-with-
magnetorheological-fluid-damping-999
[3]http://en.wikipedia.org/wiki/Suspension_(che
mitry)
[4] http://en.wikipedia.org/wiki/Sedimentation
[5] http://en.wikipedia.org/wiki/Bingham_plastic
[6]http://sstl.cee.illinois.edu/papers/MRD-
SMS.pdf
[7] http://science.nasa.gov/science-news/science-
at-nasa/2003/02apr_robotblood/
[8]http://www.intechopen.com/source/pdfs/8911
/InTech-
Impact_of_nanowires_on_the_properties_of_ma
gnetorheological_fluids_and_elastomer_composi
tes.pdf
[9]http://www.lord.com/products-and-
solutions/magneto-rheological-(mr).xml
[10]http://en.wikipedia.org/wiki/Brownian_Moti
on#Gravitational_motion

An IEEE Student Branch, UIET, Panjab University, Chandigarh initiative
IEEE Student Conference on Cognizance of
Applied Engineering and Research,
ICAER
IEEE Student Branch of University Institute of Engineering & Technology (UIET), Panjab
University, Chandigarh organized a Student Conference titled 'IEEE Student Conference on
Cognizance of Applied Engineering & Research,
of this conference, IEEE UIET succeeded in creating awareness among the students and
encourages them to participate in research activities of their field of interest.
However, apart from the students of UIET, this conference also catered to many departments
of Panjab University, colleges in and around Chandigarh, like PEC University of Technology,
CCET, PTU colleges, etc. However colleges apart from Chandigarh, like Delhi, Haryana can also
participate. The theme of this conference involves topics from every background in
Engineering. Topics were chosen from prescribed domain of Engineering, which are flexible
allowing students to manuscript for topics they wish for.
Key Features
1. Proper Peer Review Process from esteemed faculty was provided.
2. Selected papers were published in conference proceedings.
3. Best papers awarded after conference.
4. Presentation Session was held for presenting best of selected papers.
5. IEEE certified certificates to authors of selected papers were provided.

An IEEE Student Branch, UIET, Panjab University, Chandigarh initiative
IEEE Student Conference on Cognizance of
Applied Engineering and Research,
IEEE Student Branch UIET, Panjab University, Chandigarh
The initiative of this conference has been taken by the IEEE student branch, UIET. This student
branch is a part of region R-10 SAC of IEEE society. This student branch is responsible for
organizing events, creative awareness about IEEE society. The executive committee of this
section is responsible for representing this student section in various annual general meetings
in various sections.
UIET is proud to share that our Director, Professor Renu Vig, is the Sub Regional Head of IEEE.
She is a guiding factor for all of us. This student branch is headed by our branch counselor who
gives us encouragement for such activities. The following students of IEEE SB represent the
executive committee.
Branch Counselor
IEEE Student Branch
Asst Professor Y.P.Verma
Electrical and Electronics Department
UIET, Panjab University.

.
MODELING OF STATCOM AND UPFC FOR POWER
SYSTEM STEADY STATE OPERATION AND CONTROL
Vaibhav Dahiya
Author Registration No: UE111041
*
Department of EEE, UIET, PANJAB UNIVERSITY, CHD , INDIA ,
vaibhavdahiya89@gmail.com
Keywords: Power flow, Newton Raphson, FACTS
controller, STATCOM, UPFC
Abstract
In recent years, energy, environment, deregulation of power
utilities have delayed the construction of both generation
facilities and new transmission lines. These problems have
necessitated a change in traditional concepts and practices of
power systems. There are emerging technologies available,
which can help electric companies to deal with above
problems. One of such technologies is Flexible AC
Transmission Systems (FACTS). Among the converter based
FACTS devices Static Synchronous Compensator
(STATCOM) and Unified Power Flow Controller (UPFC) are
the popular FACTS devices. Considering the practical
application of the STATCOM and UPFC in power systems, it
is of importance and interest to investigate the benefits as
well as model these devices for power system steady state
operation. We have performed the power flow study of a five
bus study system without any FACTS devices and further
analyzed it with the converter based FACTS controllers.
Programming of the power flow studies stated above is
implemented with MATLAB.
1 Introduction
The electricity supply industry is undergoing a profound
transformation worldwide. Market forces, scarcer natural
resources, and an ever-increasing demand for electricity are
some of the drivers responsible for such an unprecedented
change. Against this background of rapid evolution, the
expansion programmes of many utilities are being thwarted
by a variety of well-founded, environmental, land use, and
regulatory pressures that prevent the licensing and building of
new transmission lines and electricity generating units. An in-
depth analysis of the options available for maximizing
existing transmission assets, with high levels of reliability and
stability, has pointed in the direction of power electronics.
There is general agreement that novel power electronics
equipment and techniques are potential substitutes for
conventional solutions, which are normally based on
electromechanical technologies that have slow response times
and high maintenance costs. [1] –[3].
Until recently, active and reactive power control in AC
transmission networks was exercised by carefully adjusting
transmission line impedances, as well as regulating terminal
voltages by generator excitation control and by transformer
tap changes. At times, series and shunt impedances were
employed to effectively change line impedances. FACTS
technology is most interesting for transmission planners
because it opens up new opportunities for controlling power
and enhancing the usable capacity of present, as well as new
and upgraded, lines. The possibility that current through a line
can be controlled at a reasonable cost enables a large potential
of increasing the capacity of existing lines with large
conductors, and use of one of the FACTS controllers to
enable corresponding power to flow through such lines under
normal and contingency conditions.
The importance of power flow analysis and the methods
implied are explained along with the basic formulation of
Newton Raphson power flow method in section II. In section
III modeling of the various FACTS devices are discussed in
detail along with the modeling equations. Power flow analysis
of the study system with various FACTS devices are dealt in
section IV. Section V gives the comparison of the results of
the various systems and conclusion.
2 Power Flow Analysis
Planning the operation of power systems under existing
conditions, its improvement and also its future expansion
require the load flow studies, short circuit studies and stability
studies.
Through the load flow studies we can obtain the voltage
magnitudes and angles at each bus in the steady state. This is
rather important, as the magnitudes of the bus voltages are
1

Modeling of STATCOM and UPFC for Power System Steady State Operation and Control
P
k V G

k k kk
V
k m km k m km k m
k m km k m km k m
 
 
required to be held within a specified limit. Once the bus Qk ,l k ,l
voltage magnitudes and their angles are computed using the
 = 
V V
load flow, the real and reactive power flow through each line
can be computed. Also based on the difference between
power flow in the sending and receiving ends, the losses in a
particular line can also be computed. One of the main
strengths of the Newton Raphson method is its reliability
towards convergence. Contrary to non Newton Raphson
solutions, convergence is independent of the size of the
network being solved and the number and kinds of control
m,l
Qk ,l
Vm ,l Vm,l
For k = m
Pk ,l
m ,l m,l
P
= k ,l
m,l
cal 2
equipment present in the system. So, this is the most favored
power flow method. k,l
= Qk
Vk
B kk
2.1 The Newton Raphson algorithm Pk ,l
 P
cal 2
k kk
In large-scale power flow studies, the Newton Raphson has
proved most successful owing to its strong convergence
Vk ,l
Vk ,l
characteristics.[6]. The power flow Newton Raphson Qk ,l
 P cal
V 2
G
algorithm is expressed by the following relationship 
k ,l
k k kk
P 


P / 

P /(v / v)    Q

Q
 =-  
Q / 

Q /(v / v)
 
(v / v)
 k ,l
 Qcal
V 2
B     
k ,l Vk ,l
It may be pointed out that the correction terms ∆Vm are
divided by Vm to compensate for the fact that jacobian terms
(∂Pm/∂Vm)Vm and (∂Qm/∂Vm)Vm are multiplied by Vm. It
is shown in the directive terms that this artifice yields
useful simplifying calculations
Consider the l
st
element connected between buses k and m in
Fig 2.1, for which self and mutual Jacobian terms are given
below
Figure 2.1: Equivalent Impedance
For k ≠ m
The mutual elements remain the same whether we have one
transmission line or n transmission lines terminating at the
bus k.
2.2 The sample 5 bus system
Pk ,l
m,l
=V V [G sin(  )  B cos(  )]
Pk ,l
Vm,l Vm ,l
=V V [G cos(  )  B sin(  )] Figure 2.2: The five-bus network
2

Bus no.
Bus code
(k-m)
Impedance
(R+jX)
Line charging
admittance
1 1-2 0.02+j0.06 0+j0.06
2 1-3 0.08+j0.24 0+j0.05
3 2-3 0.06+j0.18 0+j0.04
4 2-4 0.06+j0.18 0+j0.04
5 2-5 0.04+j0.12 0+j0.03
6 3-4 0.01+j0.03 0+j0.02
7 4-5 0.08+j0.24 0+j0.05
S  V I  V Y (V V )
k k vR k vR vR k vR vR k vR
vR vR vR vR k vR vR k vR vR k
k k vR k vR vR k vR vR k vR
In case study we have considered the five bus system as
shown in Fig.2.2[4-5]. The input data for the considered
system are given in table 2.1 for the bus and table 2.2 for
transmission line.
Table 2.1: Input Bus data for the study
Bus
no. Type
Generation Load Voltage
P Q P Q |v| Ø
1 slack 0 0 - - 1.06 0
2 P-V 0.4 0 0.2 0.1 1 0
3 P-Q - - 0.45 0.15 1 0
4 P-Q - - 0.4 0.05 1 0
5 P-Q - - 0.6 0.1 1 0
Assuming base quantities of 100 MVA and 100 KV
Table 2.2: Input Transmission line data for the study
system(p.u)
may change to a PQ bus in the events of limits being violated.
In such case, the generated or absorbed reactive power would
correspond to the violated limit. The power flow equations
for the STATCOM are derived below from the first principles
and assuming the following voltage source representation
Figure 3.1: STATCOM- equivalent circuits
Based on the shunt connection shown in Fig. 3.1, the
following may be written
EvR
 VvR
(cos vR
 j sin vR
)
* * * *
vR vR vR vR vR vR k
The following are the active and reactive power equations for
the converter at bus k,
P  V 2
G V V [G cos(  )  B sin(  )]
Q  V 2
B V V [G sin(  )  B cos(  )]
P  V 2
G V V [G cos(  )  B sin(   )]
The load flow result for the 5-bus system is shown in table Q  V 2
B V V [G sin(  )  B cos(  )]
2.3. All the nodal voltages are achieved to be within
acceptable voltage magnitude limits.
Table 2.3: Power flow result of study system without any
FACTS devices
Parameter BUS 1 BUS 2 BUS 3 BUS 4 BUS 5
VM(p.u) 1.06 1 0.987 0.984 0.972
VA(deg) 0 -2.06 -4.64 -4.96 -5.77
3 Power Flow Model of FACTS Devices
3.1 Power Flow model of STATCOM
The Static synchronous compensator (STATCOM) is
represented by a synchronous voltage source with minimum
and maximum voltage magnitude limits. The bus at which
STATCOM is connected is represented as a PV bus, which
3.2 Power Flow model of UPFC
The equivalent circuit consists of two coordinated
synchronous voltage sources should represent the UPFC
adequately for the purpose of fundamental frequency steady
state analysis. Such an equivalent circuit is shown in Fig. 3.2.
The UPFC voltage sources are
EvR
 VvR
(cosvR
 jsinvR
)
EcR
 VcR
(coscR
 jsin cR
)
where VvR and δvR are the controllable magnitude (VvRmin
≤ VvR ≤ VvRmax) and phase angle (0 ≤ δvR ≤2п) of the
voltage source representing the shunt converter. The
magnitude VcR and phase angle δcR of the voltage source
representing the series converter are controlled between
limits (VcRmin ≤ VcR ≤
3

Modeling of STATCOM and UPFC for Power System Steady State Operation and Control
k k kk k m km k m km k m
k k kk k m km k m km k m
m m mm m k mk m k mk m k
m m mm m k mk m k mk m k
VcRmax) and (0 ≤ δcR ≤2п), respectively. The phase angle of P  V 2
G V V [G cos(  )  B sin(  )]
the series injected voltage determines the mode of power flow
control [2], [3]. If δcR is in phase with the nodal voltage angle
cR cR mm cR k km cR k km cR k
VcR
Vm
[Gmm
cos(cR
m
)  Bmm
sin(cR
m
)]
Qk, the UPFC regulates the terminal voltage. If δcR is in Q  V 2
V V [G sin(  )  B cos(  )]
BcR cR mm cR k km cR k km cR k
quadrature with Qk, it controls active power flow, acting as a V V [G sin(  )  B cos(  )]
phase shifter. If δcR is in quadrature with line current angle
then it controls active power flow, acting as a variable series
compensator. At any other value of δcR, the UPFC operates as
a combination of voltage regulator, variable series
cR m mm cR m mm cR m
Shunt converter:
 

compensator, and phase shifter. The magnitude of the series P  V
2
G V V [G cos(  )  B sin(  )]
injected voltage determines the amount of power flow to be
controlled. Based on the equivalent circuit shown in Fig. 3.2 Q  V 2
B V V [G sin(  )  B cos(  )]
the active and reactive power equations are,
Assuming lossless converter values, the active power
supplied to the shunt converter, PvR, equals the active power
demanded by the series converter, PcR; i.e. PvR  PcR  0 .
Further more, if the coupling transformers are assumed to
contain no resistance then the active power at bus k matches
the active power at bus m. Accordingly,
PvR  PcR  Pk  Pm  0 . The UPFC power equations are
combined with those of the AC network.
4 Case Study with FACTS Controller
At bus k:
Figure 3.2: UPFC equivalent circuit
4.1 Power Flow Study with STATCOM
The STATCOM is included in the bus 3 (Fig.4.1) of the
sample system to maintain the nodal voltage at 1 p.u.
STATCOM data
The initial source voltage magnitude:1 p.u.
P  V 2
G V V [G cos(  )  B sin(  )]
Vk VcR [Gkm cos(k cR )  Bkm sin(k cR )]
Vk VvR [GvR cos(k vR )  BvR sin(k vR )]
Q  V 2
B V V [G sin(  )  B cos(  )]
Vk VcR [Gkm sin(k cR )  Bkm cos(k cR )]
Vk VvR [GvR sin(k vR )  BvR cos(k vR )]
At bus m:
P  V 2
G V V [G cos(  )  B sin(  )]
Vm
VcR
[Gmm
cos(m
cR
)  Bmm
sin(m
cR
)]
Q  V 2
B V V [G sin(  )  B cos(  )]
Phase angle: 0 degrees.
The converter reactance: 10 p.u.
V V [G sin(  )  B cos(  )]m cR mm m cR mm m cR
Series converter:
Figure 4.1: Study system with STATCOM included
4

The power flow result indicates that the STATCOM
generates 20.5 MVar in order to keep the voltage magnitude
at 1 p.u. at bus3. Use of STATCOM results in an improved
network voltage profile as shown in table 4.1.
Table 4.1: Result with STATCOM included in Bus3
VM(p.u) 1.06 1 1 0.9944 0.9752
VA(deg) 0 -2.04 -4.7526 -4.821 -5.8259
4.2 Power Flow Study with UPFC
The original five-bus network is modified to include one
UPFC to compensate the transmission line linking bus 3 and
bus 4 (Fig.4.2). UPFC should maintain real and reactive
power flowing towards bus 4 at 40 MW and 2 MVar,
respectively. The UPFC shunt converter is set to regulate the
nodal voltage magnitude at bus 3 at 1 p.u.
UPFC data
The starting values of the UPFC shunt converter are
Voltage magnitude: 1 p.u
Phase angle: 0 degrees
For series converter:
Voltage magnitude: 0.04 p.u.
Phase angle: 87.13 degrees
Reactance for both the converters: 0.1 p.u.
Figure 4.2: Study system with UPFC included
Table 4.2 shows the result of the voltage magnitude and the
phase angle with UPFC included in the system
Table 4.2: Result with UPFC included in line 6
VM(p.u) 1.06 1 1 0.9917 0.9745
VA(deg) 0 -1.7691 -6.061 -3.1905 -4.9737
5 Conclusion
The power flow for the five bus system was analyzed without
and with FACTS devices performing the Newton-Raphson
Method. The largest power flow takes place in the
transmission line connecting the two generator buses: 89.3
MW and 74.02 MVar leave bus1and 86.8 MW and 72.9
MVar arrive at bus2. The operating conditions demand a
large amount of reactive power generation by the generator
connected at bus1 (i.e. 90.82 MVar). This amount includes
the net reactive power produced by several transmission lines,
which is addressed by different FACTS devices.
The power flow result indicates that the STATCOM
generates 20.5 MVar in order to keep the voltage magnitude
at 1 p.u at bus3. Use of STATCOM results in an improved
network voltage profile, except at bus 5, which is too far
away from bus 3 to benefit from the influence of
STATCOM.
The original five-bus network is modified to include one
UPFC to compensate the transmission line linking bus 3 and
bus 4 The UPFC is used to maintain active and reactive
powers leaving UPFC, towards bus 4, at 40 MW and 2 MVar,
respectively Thus from the above analysis we find that
within the framework of traditional power transmission
concepts, the UPFC is able to control, simultaneously or
selectively, all the parameters affecting power flow in the
transmission line ( voltage, impedance, and phase angle), and
this unique capability is signified by the adjective „unified‟ in
its name.
References
[1] A.Edris, C.D. Schauder, D.R. Torgerson, L.Gyugyi,
S.L.Williams and T.R. Rietman, Oct. 1995, “The Unified
Power Flow Controller: A New Approach to Power
Transmission Control”, IEEE Trans. Power Del., Vol.10, no.
2, pp. 1085-1097.
[2] E.V Larsen, J. Urbanek, K. Clark, and S.A. Miske Jr.,
April 1994, “Characteristics and Rating Considerations of
Thyristor-Controller Series Compensation” IEEE
Transactions on Power Delivery, Vol. 9, No. 2.
[3] L.Gyugyi, and N.G. Hingorani 2000, “Understanding
FACTS:Concept and Technology of FlexibleAC Transmission
System,” Piscataway, NJ: IEEE Press
[4] R. M. Mathur, Ed., 1984, “Static Compensators for
Reactive Power Control”, Canadian Electrical Association,
Cantext Publications, Winnipeg, Manitoba
5

FAULT V0 V1 V2
Undervoltage LOW
VALUE
DECREAS
E
LOW
VALUE
Voltage
unbalance
LOW
VALUE
NO
CHANGE
INCREAS
E
Single phasing LOW
VALUE
NO
CHANGE
LARGE
INCREASE
Ground fault LARGE
INCREASE
LOW
VALUE
LOW
VALUE
L-L fault LOW
VALUE
INCREASE INCREAS
E
Inter-turn S.C LOW
VALUE
INCREASE SLIGHT
INCREASE
Overload LOW
VALUE
INCREAS
E
LOW
VALUE
MODIFIED PROTECTION SYSTEM FOR
AGRICULTUREBASED 3-PHASEINDUCTION
MOTOR
GUR GAURAV SINGH KAPIL SINGH
EEE 3RD
YEAR EEE 3RD
YEAR
UIET,PU UIET,PU
ABSTRACT:
The proposed system protects the IM from
various faults .Here the system is
designed keeping in view the requirements
of local farming sector providing cost effect
-tive device to those available in market .
INRODUCTION
This system is designed considering the problems
related to farming .In a country like INDIA where
our 56% population is related to agricultural for
feeding our 1.2 billion population. This system
can be used for cost effective protection of
3-phase IM normally used with submersible
pumps.
The various faults a 3-phase IM is prone to are-
1-Undervoltage.
2-Voltage unbalancing.
3-Single phasing.
4-Ground fault.
5-L-L short circuit.
6-Inter-turn short circuit.
7-overload.
EXPECTEDVALUETURNOUT
The various faults like undervoltage,voltage
unbalancing,overload et cetera, cause the current
value to increase and causes overheating to
motor,which further damages the insulation
system.We know the 30-40 % IM failure is due to
insulation failure.Thus protection against these
faults and thus overheating is of marked
importance.The other serious faults like short
circuit and line faults cause irrepairable damage
to winding,thus a system is required that has a
quick protective response to these.
At present the switchgear mostly being used in
agriculture sector provides only
undervoltageprotection,that too of low drop out
value,and is mechanical based.For fuses, kit kat
are beingused,which provide limited protection
and are unreliable.
WORKING-
The system uses the concept of seprating
symmetrical sequential voltage components.
V0 1 1 1
V1 = 1/3 1 a a2
V2 1 a2
a
V0=zero sequence voltage component.

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