IRJET- Review: Active Power Filtering Techniques for Power System

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 06 Issue: 03 | Mar 2019 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 2492
REVIEW: ACTIVE POWER FILTERING TECHNIQUES FOR POWER SYSTEM
Harshita Ambatkar1, Nilima B. Dhande2
1PG Scholar, Shri Sai College of Engineering and Technology, Bhadravati
2Assistant Professor, Shri Sai College of Engineering and Technology, Bhadravati
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Abstract - The term active filter is a generic one and is
applied to a group of power-electronic circuits incorporating
power switching devices and passive energy-storage-circuit
elements, such as inductors and capacitors. The functions of
these circuits vary depending on the applications. They are
generally used for controlling current harmonics in supply
networks at the low- to medium-voltage distribution level or
for reactive power and/or voltage control at high-voltage-
distribution level. In recent years there has been considerable
interest in the development and applications of active filters
because of the increasing concern over power quality, at both
distribution and consumer levels, and the need to control
reactive power and voltagestabilityattransmissionlevels. The
existing approaches are classified and assessed to provide a
framework of references for both researchers in this field and
for generators, suppliers and consumers of electrical power
who are, or may be, concerned about the problems associated
with power quality and are considering installingactive filters
for their particular sets of problems.
Key Words: Active power filter (APF), Power quality
1. INTRODUCTION
Centralized power generation systems face the dual
constraints of shortage of fuel and want to scale back the
emissions. Long distance transmission linessquaremeasure
one amongst the most causes for electric power losses. So,
stress has augmented on distributed generation (DG)
networks with integration of renewable energysystemsinto
the national grid that result in potency and reduction in
emissions. With the increase of the renewable energy
penetration into the grid, power quality of low voltage
power transmission is changing into a serious space of
interest. Most of obtainable integration of renewable energy
systems to the grid takes place with the help of power
physics converters. The first use of the ability electronic
converters is to integrate the metric weight unit to the grid
in compliance with power quality standards. But, high
frequency switch of inverters will inject a lotofharmonicsto
the systems, making major PQ issues if it's not enforced
properly.
Filtering strategies like Hybrid Filtering (Combination
of series passive and shunt Active Power Filter) &
Inductively Active Filtering square measure the most recent
development of interfacing devices between distribution
offer (grid) and client appliances to beat voltage/current
disturbances and improve the ability quality by
compensatingthereactiveandharmonicpowergeneratedor
absorbed by the load.
Solar is that the one amongst most promising metric weight
unit sources and their penetration level to the grid is on the
increase. Though the advantage of Distributed generation
includes voltage support, decrease in transmission &
distribution losses and improved response. PQ issues are of
growing concern. This paper deals with a groundwork and
development of PQ issues associatedwithsolarintegrated to
the grid and also the impact of poor power quality. The
affiliation topologies of filtering into the system to beat the
PQ issues are mentioned.
2. Active Power Filter
2.1. Shunt active power filter
Depending on the actual application or electrical drawback
to be resolved, active power filters will be enforced as shunt
type, series type, or a combination of shunt and series active
filters (shunt-series type). These filters may also be
combined with passive filters to make hybrid power filters.
The shunt-connected active power filter as shown in Fig.1,
with a self-controlled dc bus, includes a topology kind oflike
that of a static compensator (STATCOM) used for reactive
power compensation in power transmission systems. Shunt
active power filters compensate load current harmonics by
injecting equal-but opposite harmonic compensating
current. During this case the shunt active power filter
operates as a currentsupplyinjectingtheharmonicelements
generated by the load however phase-shifted by 180°.
Fig-1: Series active power filter

2.2. Series active power filter
Series active power filters as showninFig.2wereintroduced
by the tip of the 1980’s and operates in the main as a
transformer and as a harmonic isolator between the
nonlinear load and also the utility system. The series-
connected filter protects the buyer from associate
inadequate offer voltage quality. this kind of approach is
particularly suggested for compensation of voltage
unbalances associated voltage sags from the ac offer and for
low-power applications and represents an economically
enticing various to UPS, since no energy storage (battery) is
critical and also the overall rating of the parts is smaller.
The series active filter injects a voltage partnonparallel with
the provision voltage and so may be considered a controlled
voltage supply, compensating voltage sags and swellsonthe
load aspect. In several cases, series active filters work as
hybrid topologies with passive LC filters. If passive LC filters
area unit connected in parallel to the load, the Voltage
stabilizer mistreatment seriesactivepowerfilteroperates as
a harmonic isolator, forcing the load current harmonics to
flow into in the main through the passive filter insteadofthe
ability distribution system.
Fig-2: Series active power filter
2.3. Unified power quality conditioner
The series-shunt active filter could be a combination of the
series active filter and therefore the shunt active filter. The
shunt active filter is found at the load aspect and might be
accustomed atone for the load harmonics. On the opposite
hand, the series portion is at the supply aspect and might act
as a harmonic interference filter. This topology has been
referred to as the Unified Power Quality conditioner.
3. DIFFERENT TECHNIQUES FOR ACTIVE POWER
FILTERING
In one in all the strategy [1] group action an energeticpower
filter with a solar photovoltaic (PV) generation supply, that
use constant electrical converter for connecting to the
network. Through this integration a double aim is fulfilled:
on the one hand the power quality is improved through the
compensation capability of active power filters, and on the
opposite an additional contribution of active power is
equipped by PV system. The facility system operation is
analyzed through the instant power theory and simulated
victimization MATLAB Simulink atmosphere. This can be a
possible answer for the expansion designing of isolated
systems, whereas the operation and maintenance prices
additionally as energy losses may be reduced.
A method for dominant a vigorous power filtervictimization
neural networks is conferred [2]. Currently, there's a rise of
voltage and current harmonics in power systems, caused by
nonlinear loads. The active power filters (APFs) square
measure wont to compensate the generated harmonics and
to correct the load power issue. The planned management
style may be a pulse dimension modulation management
(PWM) with 2 blocks that embody neural networks. Neural
networks estimate the reference compensationcurrents. On
the opposite hand, a multilayer perceptron feed-forward
network (trained by a backpropagation algorithm) that
works as a hysteresis phenomenon band comparator is
employed.
Fig-3: Basic combined scheme of an active power filter
and a PV system
New management algorithmicprogramfora vigorouspower
filter (APF) to compensate harmonic and reactivepowerofa
3-phase thyristor bridge rectifier underneath non-ideal
mains voltage eventualities was conferred [3]. Sensing load
current, dc bus voltage and supply voltagesreasonreference
currents of the APF. APF driving signals are created with
these signals via a physical phenomenon band current
controller. Matlab/simulink facility tool case is employed to
simulate the projected system. The projected method’s
performance is compared with typical instant power (p–q)
theory. The simulation results are conferred and mentioned
showing the effectiveness of the management algorithmic
program. The projected algorithmic program is found quite
satisfactory to compensate the reactive power and
harmonics underneath non-ideal mains voltage conditions.
A single-phase two-wire electrical converter system for
photovoltaic (PV) power injection and active powerfiltering

(APF) with nonlinear inductance thought was projected [4].
The projected system will totally or partly perform APF,
method PV power, eliminate harmonic currents, improve
power issue, and take into consideration the nonlinear
impact of its output filter inductance. Within the system,
albeit solely the utility current is detected, each APF and
most electric receptacle trailing options may be still
achieved, reducing the quantity of current sensors andprice
considerably. To forestall outputcurrentfromextraordinary
switch ratings, electrical converter current is correctly
controlled through a current controller andanoutlinedlimit
circle. A self-learning algorithmic rule is additionally
projected to see nonlinear inductance, which mightincrease
the accuracy of the calculable current.
Fig-4: Schematic block diagram of three-phase shunt APF
system [3]
The system will trot out PV power, compensate current
harmonics, and improve power issue at the same time.
Although solely a current detector is placed at the utility
aspect, the required options will be still achieved. Withinthe
style, the utility current commands area unit derived to
effectively utilize the electrical converter system. A current
expert is employed to guage electrical converter current to
stop output power from extraordinary the switch current
ratings. Additionally, a self-learning rule is additionally
projected and distribution is applied to spot the nonlinear
impact of the filter electrical device. A DSP chip
(TMS320F240) is adopted to see the utility current-
command, notice the present expert, and come through an
MPPT feature in order that the management circuits of the
PV electrical converter system area unit compact and
programmable.
The simulation and experimental study of proportional
integrator (PI) controlled DC bus voltage of 3 part shunt
active power filter (APF) to enhance power quality by
compensating harmonics and reactive power needed by
nonlinear load is projected [5]. The compensation method
relies on sensing mains currents solely, AN approach totally
different from standard ways, that sometimes need
harmonics or reactive var values of the load. The non-
sinusoidal mains voltage downside is resolved by
victimization partboltedloop(PLL)system.Pulsedimension
modulation (PWM) signal generation relies on physical
phenomenon management comparators to get the change
signals.
Fig-5: APF system configuration and currents waveforms
[5]
The performance of the PI controller has been studied on
simulation has been developed in real time method with an
xPC Target system and with success tested within the
laboratory to verify the simulation results. It’s clear from
simulation and experimental results that the compensation
method is straightforward, and relies on sensing one supply
voltage, electrical compensation voltage and 3 line currents
solely. In spite of high frequency voltage supply wave
because of this, the obtained current is synchronic with the
voltage, that annihilates reactive power and harmonics area
unit rejected. The total harmonics distortion (THD) of the
supply current once compensation is well below five-hitter,
the harmonics limit obligatory by the IEEE-519
commonplace.
One of the tactic, [6] describes adjective methodology for
compensating the reactive power with a vigorous power
filter (APF), that is ab initio rated for mitigation of solely the
harmonic currents given by a nonlinear industrial load. It’s
established that, if the harmonic currents don't load theAPF
at the rated power, the offered power is wont to offer a
neighborhood of the specified reactive power. Totally
different indicators for coming upwithsuchapplicationarea
unit given, and it's established that the planned adjustive
algorithmic program represents another price to the APF.
The algorithmic program is much validona laboratorysetup
with a 7-kVA APF.
The planned algorithmic program compensates the reactive
power if the APF electrical converter current limit isn't
reached. The principle is predicated on calculation of fast d-
and q-axes currents to work out by completely different
suggests that the common price of reactive current (i.e., q-
axis) obligatory as reference.
Active power filters (APFs) are wont to compensate
harmonics, reactive current and negative sequence first
harmonic current of load current drawn by nonlinear

masses. The pliability of selective compensation, if provided
within the management theme, makes APF versatile device
for compensation of reactive power, harmonic currents and
unbalance in supply currents andtheircombos,relyingupon
the restricted rating of the voltage-source electrical
converter utilized as an APF. The planned theme [7]
decomposes the load current into positive and negative
sequence first harmonic active parts, reactive element and
harmonic parts in synchronous reference frames. The
management theme performs with priority-based theme,
that respects the restricted rating of the APF. The simulated
ends up in MATLAB surroundings and experimental results
of the developed paradigm of APF are conferred to validate
the effectiveness of the planned management theme. Digital
signal processor based mostly implementation of
management theme is additionally elaborated for selective
compensation of power-quality issues with details of
developed paradigm.
Fig-6: General diagram of the laboratory setup. The APF
compensate the harmonics and the reactive power from
the ASD and the RL load.
A new current decomposition technique supported SRF
theory with indirect current management for prioritized
selective compensation of power-quality parts has been
investigated for APF. The determined performance of the
active filter has incontestable the power of the planned
management technique to by selection compensate the
present harmonics, unbalanced loading and reactive power,
supported priority to respect therestrictedpowercapability
of the VSI. Associate experimental study hasbeenconducted
and has valid the effectiveness of the planned theme. it's
additionally been determined that the planned theme
includes a quick response and is in a position to keep up
close to curved supply current for harmonic compensation
conformist to IEEE-519 commonplace and is in a position to
self support the dc bus. The theme has the advantage of
flexibility of choice of the power-quality indices that
references could also be computed. The theme alongside
indirect current management has offered automatic
compensation of part lag, which might have otherwise
occurred thanks to passive ripple filters etc. The theme
generally could also beapplicabletoalternativetopologiesof
active and hybrid power filters/conditioners. In a very shell
it's suggested that below restricted power capability of the
VSI of APF active power conditioner with indirect current
management with prioritizedthemecompensationprovided
by the planned theme offers appropriate answer to
uncertainties in grid thanks to current quality issues.
One of the techniques gift an immediate current-space-
vector management [8] of a lively power filter (APF)
supported a three-level neutral-point-clamped (NPC)
voltage-source electrical converter. The projected
methodology indirectly generates thecompensationcurrent
reference by victimization a similar electrical phenomenon
of the basic part victimization APF’s dc-link voltage
management. The projected management will by selection
opt for harmonic current parts by real time quick Fourier
rework to get the compensation current.
The compensation current is delineating during a rotating
system with chosen shift states from a shift table enforced
during a field-programmable gate array. Additionally, a 3
part four-wire APF supported a three-level neutral-point-
clamped electrical converter is additionally conferred. The
projected APF eliminates harmonics altogether 3 phases
similarly because the neutral current. A three-phase three-
wire NonproliferationCenterelectrical convertersystem will
be used as a three-phase four wire system since the split dc
capacitors offer a neutral affiliation. to control and balance
the split dc-capacitor voltages, a brand new management
methodology employing a sign cubiform physical
phenomenon controller is projected. The characteristics of
the APF system with associate degree LCL-ripple filter area
unit investigated and compared with ancient current
management methods to judge the inherent blessings.
One of the methodology presents an on the direct current-
space-vector management of a full of life power filter (APF)
supported a three-level neutral-point-clamped (NPC)
voltage-source electrical converter. The planned technique
indirectly generates the compensation current reference by
exploitation identical electrical phenomenon of the
elemental part exploitation APF’s dc-link voltage
management. The planned management will by selection
select harmonic current elements by real time quick Fourier
rework to get the compensation current.
The compensation current is painted in a very rotating
reference system with chosen shift states from a shift table
enforced in a very field-programmable gate array.
Additionally, a three phase four-wireAPFsupporteda three-
level neutral-point-clamped electrical converter is
additionally given. The planned APF eliminates harmonics

altogether three phases further because the neutral current.
A three-phase three-wire authority electrical converter
system will be used as a three-phase four wire system since
the split dc capacitors give a neutral association.
To regulate and balance the split dc-capacitor voltages, a
brand new management techniqueemployinga signcuboids
physical phenomenon controller is planned. The
characteristics of the APF system with AN LCL-ripple filter
area unit investigated and compared with ancient current
management ways to judge the inherent blessings.
An industrial controller, specifically designed for two- and
three-level converters, was tailored to figure on an
asymmetrical nine-level active power filter (APF) [9]. The
controller is currently ready to build all needed tasks for the
proper operation of the APF, like current-harmonic
elimination and removal of high-frequency noise. The low
switching-frequency operationofthenine-level devicewasa
very important advantage within the application of the
commercial controller. Additionally, with the nine-level
filter, change losses were considerably reduced. The filter
was designed to figure as voltage supply and operates as
harmonic isolator, up the filtering characteristics of the
passive filter. The management strategy for sleuthing
current harmonics relies on the “p−q theory” and also the
phase-tracking system in an exceedingly synchronous
organization phase-locked loop. The dc-link voltage
management is analyzed along with the impact of controller
gain and delay time withinthesystem’sstability.Simulations
for this application area unit displayed and experiments in
an exceedingly 1-kVA model, victimization the same
industrial controller, weretested,collateral theeffectiveness
of this new application.
A control algorithmic program for a three-phase hybrid
power filter is planned [10]. It’s grooved by a series active
filter and a passive filter connected in parallel with the load.
The management strategy is predicated on the vectorial
theory twin formulation of instant reactive power, in order
that the voltage wave shape injected by the active filter is
ready to compensate the reactive power and therefore the
load current harmonicsandtobalanceasymmetrical masses.
The planned algorithmic program conjointly improves the
behavior of the passive filter. Simulations are administrated
on the MATLAB-Simulink platform with totally different
masses and with variation within the supply electrical
resistance.
A new current controller theme for selective harmonic
compensation is planned for shunt active power filters [11].
The strategy employs associate degree array of resonant
current controllers, one for the elemental, and one for every
harmonic, enforced in basic arrangement so as to cut back
the machine effort. The planned controller style
methodology is predicated on the pole-zero cancellation
technique, taking under consideration the load transfer
operates at every harmonic frequency. Two style ways are
provided, that provide controller transfer functions with
superior frequency response.Theentirecurrentcontrolleris
realized because thesuperpositionofall individual harmonic
controllers. The frequency response of the complete control
system management is perfect with reference to filtering
objectives, i.e. the system provides sensible overall stability
and wonderful property for attention-grabbing harmonics.
This conclusion is supported by experimental results on a
seven. 6 kVA laboratory filter, indicating a discount in
current doctorate issue from thirty four you must 2
Chronicles, whereas the best harmonic paid is thatthethirty
seventh harmonic current.
Modern technique proposes the effective utilization of
unified power quality conditioner (UPQC) for
interconnecting the PV modules to the grid exploitation
power angle controller (PAC) methodology [12]. A shunt
active power filter (APF) is employed to evacuate the ability
from the electrical phenomenon module additionally to
compensating this harmonics, load unbalance and reactive
power. To accomplish this the series APF within the UPQC is
employed for provision an area or whole reactive power
needed by the load additionally to compensating the sag,
swell, provide voltage unbalance and distortions. This is
often created doable by dominant the point in time and
magnitude of series injected voltage known as power angle
management methodology. The reactive power and voltage
compensation technique introduces a part shiftbetweenthe
load terminal voltage and supply voltage. The transient
thanks to sudden part shift is reduced exploitation step by
step introduction of series compensation voltage. The
projected methodology effectivelyutilizestheshuntAPFand
series APF within the UPQC for interconnecting the PV
module to the grid.
The deals with indirect current controlled shunt active
power filter (APF) for up power quality by reactive power
compensation and harmonic filtering [13]. The projected
APF relies on a voltage supply electrical converter(VSI).The
VSI is controlled by 2 loops, the voltage management loop
and also the current management loop. The voltage
management loop regulates the DC link electrical condenser
voltage and also the current management loop usesphysical
phenomenon band management to form the supply current
specified it's in-phase with and of identical form becausethe
input voltage. The main advantage of the projected APF is
that the reference current for power quality improvementis
generated from the DC link electrical condenser voltage.
Repetitive controller (RC), which may come through zero
steady-state error trailing of any amounted signal with
renowned number period, offers active power filters (APFs)
a promising correct current management theme to
compensate the harmonic distortion caused by nonlinear
hundreds. However, classical RC cannot specifically
compensate periodic signals of variable frequency and
would cause vital performance degradation of APFs. In one
amongst the methodology, a fractional- order RC (FORC)

strategy at a set rate is projected to subsume any periodic
signal of variable frequency, wherever a Lagrange-
interpolation-based third delay (FD) filter is employed to
approximate the factional delay things. The synthesis and
analysis of FORC systems are given. The projected FORC
offers quick on-line calibration of the FD and also the quick
update of the coefficients, so provides APFs with a
straightforward however terribly correct real time
frequency-adaptive management answer to the elimination
of harmonic distortions underneath grid frequency
variations. A case study on a single-phase shunt APF is
conducted.
4. CONCLUSIONS
In this paper, the different methodology and techniques was
presented for utilization of active power filter for
improvement of power quality of power system, transient
improvement of power system, and minimizationofaffectof
solar and wind integrated power system.
These paper very much useful for clear the idea about active
power filter and itsimplementationusingsoftwareapproach
or in simulation software. That very much helpful for
students and researcher which working in field of active
power filter designing.
REFERENCES
[1] Pontoriero, Doming H., and Pedro E. Mercado."Network
compensation with active power filters integratedto PV
generation." Power Tech Proceedings, 2001 IEEEPorto.
Vol. 2. IEEE, 2001.
[2] Vazquez, J. R., and P. Salmeron. "Active power filter
control using neural network technologies." IEE
Proceedings-Electric Power Applications 150.2 (2003):
139-145.
[3] Kale, Murat, and Engin Özdemir."Harmonic andreactive
power compensation with shunt active power filter
under non-ideal mains voltage." Electric PowerSystems
Research 74.3 (2005): 363-370.
[4] Wu, Tsai-Fu, et al. "A single-phaseinvertersystemforPV
power injection and active power filtering with
nonlinearinductorconsideration." IEEETransactionson
Industry Applications 41.4 (2005): 1075-1083.
[5] Chaoui, Abdelmadjid, et al. "PI controlled three-phase
shunt active power filter for power quality
improvement." Electric Power Components and
Systems 35.12 (2007): 1331-1344.
[6] Asiminoaei, Lucian, et al. "Adaptive compensation of
reactive power with shunt active power filters." IEEE
TransactionsonIndustryApplications 44.3(2008):867-
877.
[7] Singh, Bhim, and Vishal Verma. "Selectivecompensation
of power-quality problems through active power filter
by current decomposition." IEEETransactionsonPower
Delivery 23.2 (2008): 792-799.
[8] Vodyakho, Oleg, and Chris C. Mi. "Three-level inverter-
based shunt active power filter in three-phase three-
wire and four-wire systems." IEEE transactions on
power electronics 24.5 (2009): 1350-1363.
[9] Varschavsky, Alexander, et al. "Cascaded nine-level
inverter for hybrid-series active power filter, using
industrial controller." IEEE Transactions on Industrial
Electronics 57.8 (2010): 2761-2767.
[10] Salmeron, Patricio, and Salvador P. Litran.
"Improvement of the electric power quality using series
active and shunt passive filters." IEEE transactions on
power delivery 25.2 (2010): 1058-1067.
[11] Lascu, Cristian, et al. "High performance current
controller for selectiveharmoniccompensationinactive
power filters." IEEE TRANSACTIONS ON POWER
ELECTRONICS PE 22.5 (2007): 1826.
[12] Palanisamy, K., et al. "Effective utilization of unified
power quality conditioner for interconnecting PV
modules with grid using power angle control
method." International Journal of Electrical Power &
Energy Systems 48 (2013): 131-138.
[13] Mahanty, R. "Indirect current controlled shunt active
power filter for power quality
improvement." International Journal ofElectrical Power
& Energy Systems 62 (2014): 441-449.

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