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Transcript
DESIGN AND DEVELOPMENT OF THREE SINGLE PHASE PASSIVE
FILTER (FOR CFL LAMP LOAD) AND STUDY OF SIMULATION
RESULTS OF ACTIVE AND PASSIVE FILTER
Snehal Gadekar, Namrata Kulkarni, Prof.H.H.Kulkarni, Miss.Sheetal Mhetre
P.E.S.’s Modern College Of Engineering, Pune
[email protected], [email protected]
Abstract- Now a days use of nonlinear devices
has been increased to a large extend. In the
power system reforms some of the power
supplying companies takes into consideration the
presence of harmonics as one of the parameter in
the tariff. Therefore as we control the p.f. within
the limit using APFC panel, it is today’s need to
use appropriate filter to control the harmonics.
This paper presents the study of harmonics
present in an educational Institute and hardware
design of passive filter. Readings are taken with
and without filter to validate the developed
hardware. The simulation work is also carried
out in MATLAB to compare the results of Active
and passive filter.
Index Terms- Harmonics, Non-linear load, Passive
Filter, Active filter.
I.INTRODUCTION:
The presence of harmonics in a power
system can give rise to a variety of problems
including equipment overheating, reduced power
factors, deteriorating performance of electrical
equipment, the incorrect operation of protective
relays, interference with communication devices,
and in some cases, circuit resonance to cause
electric apparatus dielectric failure and other types
of severe damage.[2] Even worse, harmonic
currents generated in one area can penetrate into the
power grid and propagate into other areas, resulting
in voltage and current distortions for the entire
system. This phenomenon has become a major
concern for power quality due to the ever-increasing
usage of electronic devices and equipment in power
systems.
The harmonic is defined in many literatures as “a
component of a periodic wave having a frequency
that is an integral multiple of the fundamental
power line frequency” [1].
The meaning of the harmonic can be easily
explained using the following example. Let ‘f’
represents a fundamental frequency, the second
harmonic has frequency 2f Hz, third harmonic has
frequency 3fHz ,and so on. The 2nd ,4th,6th,etc.,are
called even harmonics while the 3rd,5th,7th,etc.,are
called odd harmonics.[1]There are two types of
harmonics Voltage Harmonics and Current
Harmonics
The harmonic distortion occurs when nonlinear loads, such as rectifier, inverter, adapters,
etc., are fed from power systems and changes
sinusoidal wave at a fundamental frequency to
different non-sinusoidal waves [3] as shown in
Fig.1
[Type here]

Fig.1 Effect of Non-linear load on electrical power
system
II. HARMONICS AND ITS EFFECTS:
Table I. Harmonics and its effects:
Sr.
No
1.
General
2.
Motors
3.
Generators
4.
Transforme Increases
audible
noise,
-rs
Increases losses like Cu
losses, stray flux losses, Iron
losses, causes losses
Power
Voltage stress and corona
cables
Electronic
Malfunctioning
Equipment
Metering
Erroneous operation
Switchgear Increases heating and losses,
And
slower operation ,changes in
Relaying
operating characteristics
5.
6.
7.
8.
Effects of Harmonics
Heating, Thermal or voltage
stress, aging of electrical
insulations
Flux distribution in air gap,
cogging or crawling
High stressed mechanical
forces , temperature rise
Non-linear loads:
The effects discussed above are because of the nonlinear load. These are the loads in which the current
wave form does not resemble the applied voltage
waveform due to a number of reasons, for e.g. the
use of electronic switches that conduct load current
only during a fraction of power frequency period.
Therefore, it can conceive non-linear loads as those
which Ohm’s law cannot describe the relation
between V and I.
Those loads are listed below:
1. Power Electronics:
 Variable frequency drives
 Power converters
 Cycloconverters
 Cranes
 Elevators
 UPS
 Battery Chargers
 Inverters
2. ARC Devices:
 Fluorescent Lighting
 Arc furnaces
 Welding machines
III.MITIGATION TECHNIQUES:
1. Passive Filters:
Passive filters are very much helpful for
mitigation of harmonic component & used
traditionally. Continuous development has been
reported in this technique for betterment of
filter. It helps to achieve the optimum utilization
with reduced rating & cost. The use of passive
filter in the mitigation of harmonic in 3 phase
system uses the utilizing reactor & capacitor [5].
Fig.2 Effect of Harmonics
[Type here]
2. Active Filter:
To reduce the harmonics conventionally
passive L–C filters were used and also
capacitors were employed to improve the
power factor of the ac loads. But the
passive filters have several drawbacks like
fixed compensation, large size and
resonance problem.[4] To mitigate the
harmonics problem APF is the better
solution but it involves high cost. In this
filter equal and opposite component is
developed to mitigate the harmonics.
IV.CASE STUDY:

Set up :
An experimental set up has been developed
in the laboratory to study the presence of
harmonics and its mitigation using passive
filter. The load considered is the series
combination of Resistive and Inductive
Bank. Instead of using normal bulb,
purposely CFL lamps are used which are
prone to create the harmonics. With the help
of Harmonic power analyzer harmonic
distortions has been recorded. With these
observations a passive filter has been
designed and developed. It is connected in
the B phase. Readings are taken with and
without filter.
Fig.3 Experimental set up
Table II: Observed power
filter
Load Phase V
I
(Volt) (Amp)
1.RL R
241
1.89
Y
254
2.23
B
218
1.82
2.RL R
223
3.49
Y
263
3.36
B
222
3.63
3.RL R
231
4.43
Y
266
4.70
B
211
4.50
factor without
kW
PF
0.1
0.22
0.28
0.28
0.36
0.42
0.32
0.62
0.56
0.512
0.37
0.317
The THD values observed for above loading
conditions are as follows
Table III: observed ITHD without filter
Load Phase
VTHD
ITHD
1.RL R
14.58
10.836
Y
14.36
8.725
B
16.67
7.9
2.RL R
14.28
6.4
Y
12.39
9.17
B
14.48
5.77
3.RL R
12.20
6.21
Y
11.16
7.28
B
14.39
6.147
Table II and III shows the readings without
filter.Reading are taken at the same loading
conditions with use of passive filter. The
results are shown below in table IV.It is
observed that
current
totalharmonic
distortion has been reduced after connecting
filter .
Table IV: observed ITHD with filter
Load
Phase
ITHD
1.RL
R
7.20
Y
10.4
B
6.80
2.RL
R
6.80
Y
8.10
B
6.90
[Type here]
3.RL
R
Y
B
6.00
7.00
5.40
From the above results the average power factor is
considered as 0.5
V. HARDWARE AND SOFTWARE WORK
PERFORMED
0.55
0.60
0.65
0.768
0.583
0.419
0.899
0.714
0.549
1.034 1.190 1.518
0.849 1.005 1.333
0.658 0.840 1.169
From this information, now we can calculate the
capacitor size for power factor correction. The
formula to calculate the required kVAR is:
Factor from Table 1 below x kW = kVAR of
capacitors required.
1. Design of passive filter for component selection:
kW= VI cosØ/100
Capacitor sizing for power factor correction:
=230*5*0.5/1000
Commonly used method for power factor correction
using the capacitor to generate reactive power
(kVAR) to reduce apparent power (kVA) form
inductive load. This time we want share a simple
method to sizing our capacitor to improve power
factor for induction motor and utility electricity.
This method also can use for capacitor bank sizing.
Power factor correction is the one of famous topic
for all electrical people at around the world. Many
discussion and debate about how to sizing the
capacitor for power factor correction.

How to sizing capacitor for power factor
correction?
To properly sizing the amount of capacitor
(kVAR) required to correct the lagging
power factor, we must have three (3)
important of information below:
1. kW (kilowatts)
2. Existing Power Factor (%)
3. Desired Power Factor (%)
The values of the factor to be multiply are
selected from the following table:
Table No.V
Actual
Desired PF
PF
0.8000 0.850 0.900 0.950 1.000
0.5
0.982 1.112 1.248 1.403 1.732
=0.575 kW
Now, observed power factor is 0.5 and to calculate
kVAR the desired is to be selected from the Table
No.5
Multiplying Factor= 1.732
kVAR= kW* multiplying factor of PF
=0.575*1.732
=0.9959 kVAR
For calculation of Capcitor the considered standard
is 1 kVAR is corresponding to 8µF
Now, for 0.9959*8= 7.967µF
Fc= 189 Hz
2. Selection of reactor:
Reactor to be used is selected on the basis of the
order of the harmonic to be reduced. In our case we
have selected 5% reactor.
L=5 mH
[Type here]
Fc= 1/2∏√(LC)
Therefore
C= 0.1419µF
3. MATLAB Simulation of Passive filter:
Fig.4 Input, Output and THD content of Passive
filter model
4. MATLAB Simulation of Active filter:
Fig.1 MATLAB simulation model without passive
filter
Fig.5 MATLAB simulation model without active
filter
Fig.2 Results without passive filter
Fig.6 Results without active filter
Fig.3 MATLAB Simulation model with passive
filter
[Type here]
VIII. REFERENCES:
[1] IEEE Std 519-1992, ‘IEEE Recommended
Practices and Requirements for Harmonic Control
in Electrical Power Systems’, New York, NY:
IEEE.
[2] ‘Harmonics & Power system’ by Francisco. C.
De. La Rosa, Distribution Control system, Inc.
Hazelwood, Missouri, U. S.A.
Fig.7 Simulation Model for Active Filter
[3] Joseph, S. and J.R. Subjak, 1990. ‘Harmonics
Causes, Effects, Measurements and Analysis: An
Update’ IEEE Transaction on Industry Application,
Vol. 26. No 6.
[4] M.H. J. Bollen, “Understanding Power Quality
Problems”, IEEE Press, Piscataway
,(2000).
[5] Barbow,Hayes & Horowitz, Rizzoni,’Passive
Filter’ECE60L Lecture Notes, Spring 2004,
Fig.8 Input, output and THD content of Simulation
model of active filter.
VI. CONCLUSION:
The Active power filter gives better results as
compared to passive filter and this is observed with
the help of waveforms obtained from MATLAB
simulation models.
[6] Kuldeep Kumar Srivastava, Saquib Shakil,
Anand Vardhan Pandey, ‘Harmonics & its
mitigation
technique
by
passive
shunt
filter’,International Journal of Soft Computing and
Engineering (IJSCE) ISSN: 2231-2307, Volume-3,
Issue-2, May 2013
[7] Francisco c. De La rosa , ‘HARMONICS AND
POWER SYSTEMS’, Distribution Control Systems,
Inc. Hazelwood, Missouri, U.S.A.
[8] ABB ‘Technical Guide Number 6 to Harmonics
with AC drives’
VII. ACKNOWLEDGEMENT:
Authors wish to thank the authorities of Progressive
Education Society’s Modern College of Engineering,
Pune, Maharashtra, India for their necessary help.
[9]Dugan, E.C., McGranagham, M.F., Santoso, S.,
Beaty, H.W.,’Electricalpower systems quality.
McGraw-Hill, 2002’
[10]Gonzalo Sandoval & John Houdek, ‘A Review
of Harmonic Mitigation Techniques’ © 2005
[Type here]
[11] ] S.Islam, “Characteristic and Noncharacteristic Harmonics, Harmonic Cancellations
and Relevant In- ternational Standard in Variable
Speed Drives,” Science and Technology, 2002
[12] Zubair Ahmed Memon, Muhammad Aslam
Uquaili, And Mansoor Ahmed Soomro,
‘Experimental Analysis of Harmonic Mitigation
Effects on Three Phase Six Pulse Converter by
Using Shunt Passive Filter ’
[13]Hammond power solutions inc. ‘Harmonic
Mitigation, Power Factor Correction & Energy
Saving with Proper Transformer & Phase Shifting
Techniques ‘
[14] Starline ‘Neutral Ratings For Power
Distribution Systems in the Data Center’
[15] ABB technical application papers ‘Power
factor correction and harmonic filtering in
electrical plants’