Control and Implementation of a Standalone DG-SPV-BES micro-grid System using DSTATCOM

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 11 | Nov -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 247
Control and Implementation of a Standalone DG-SPV-BES micro-grid
system Using DSTATCOM
M.SOMNATH REDDY1, M.RAVIKUMAR2, J.CHINNAVANNUR SWAMY3, P.A.PRABHAKARA4
1PG Scholor, Dept of EEE (PE), SSSISE, Andhrapradesh, India
2,3Assistant Professor, Dept of EEE, SSSISE, Andhrapradesh, India
4Head of the department, Dept of EEE, SSSISE, Andhrapradesh, India
---------------------------------------------------------------------***---------------------------------------------------------------------
Abstract:- This paper exhibits a control calculation for
isolated sun based photo voltaic (PV) diesel battery hybrid
system with incorporated D-STATCOM. The admittance based
control calculation is utilized for stack adjusting, music
disposal, and responsive power pay under three phase four
wire direct and nonlinear loads. The PV cluster is controlled
utilizing a most extreme power point following (MPPT)
calculation to get the greatest power under eccentric working
conditions. The battery vitality stockpiling system (BESS) is
incorporated with diesel motor generator set for the
organized load administration and power stream inside the
system. Further, the proposed system with the assistance of D
STATCOM enhances the power quality issues and abatements
the aggregate symphonious diversion. A four-leg voltage-
source converter with BESS likewise gives impartial current
pay. The execution of the proposed independent hybridsystem
with coordinated D-STATCOM is examined under various
stacking conditions created MATLAB/Simulation of the
system.
INTRODUCTION
A GLOBAL alteration to renewable energy resources is well
suitable to meet the requirement for powerinisolatedareas,
which lack grid and road infrastructure. The support for the
use of renewable energy resources is growing as global
warming is a main ecological worry, and it compromises an
alternative for future energy supply. Among the available
renewable energy resources, solar photovoltaic (PV) power
generation is purchase wide approval, and it is used for
numerous requests such as domestic appliances, isolated
missions,data communications,telecommunicationsystems,
hospitals, electric aircraft, and solar cars . The application of
the PV power generation is for the aims that it has many
advantages such as it gives clean power, is convenient in
nature, and can be engaged for numerous small-scale
applications. However, making an allowance for the large
variations in the output of PV power, it is imperative to
incorporate other powersourceslikea diesel generator(DG)
set, battery storage, fuel cells, etc. The performance analysis
of standalone systems with PV- and DG-based sources is
given in.
The design and operation of standalone DG-SPV-
battery energy storage (BES) using a peak recognitionbased
control method is shown in. A character triangle function
(CTF)-based control approach and its analysis for four-wire
standalone distribution system are verified.
An improved phase-locked loop (EPLL)-based
control method is shown in, wherein three EPLLs are used
for withdrawal of fundamental active and reactive power
components of load currents. However, the simulation
studies are presented in. A compound observer-based
control method for standalone PV-DG-based system is used
in.
However,theauthors haveprovidinginvestigational
results, but the control method in is complex and needs
modification of internal parameters. Unlike the control
method in, the proposed system uses a conductance-based
simple control method. Moreover, a comprehensive
investigational study is used to validate all the topographies
of the system. The proposed system contains of a diesel-
engine-driven permanent magnet synchronous generator
(PMSG), PV array, and BES. This micro grid is a
demonstrative of a typical rural hospital power supply
system which needs to ensure continuous and constant
power supply for 24 × 7 h.
Therefore, the PMSG driven by a diesel engine safe guards
controlled power supply. In order to preserve the efficiency
and to decrease the maintenance cost, the DG set is made to
function at 80–100% of its full capacity. This is because,
under light-load conditions, the efficiency decreases andthe
maintenance cost also increases as the DG set is exposed to
carbon build up. Typically, to avoid these difficulties, the DG
is operated by possession a least loading of80% bymeans of
battery charging or the DG is made to turn ON/OFF
dependent upon the loading. However, the turn ON/OFF of
the DG set is frequently not suggested.
1) The load might different currently. Therefore, the
frequent turn ON/OFF of DG intensifications the mechanical
maintenance.
2) The battery life decreases as the discharging current is
high for the duration of transient periods.
Besides, the PMSG driven by the diesel engine does not need
a separate excitation control. The machine is robust,
efficient, brushless construction, and with lessmaintenance.
A battery energy storage system (BESS) is combined to
deliver load smoothing in the case of dissimilarities in PV
array output power.
The BESS is deliberated as ideal energy storage for a
separate system as related to compressed air, super
capacitors, fly-wheels, pumped hydro, and superconducting

magnetic storage. The employment of a separate system
devised of PV array, DG set, and BESS intends to fulfill the
following necessities.
1) To control the point of common coupling (PCC) voltage
dependent upon the solar irradiance variations, and load
variations and unbalances.
2) There is no obligation for the measurement of load for
turn ON/OFF of DG.
3) The power quality of the system is enhanced by dipping
the total harmonic distortion (THD) of PCC voltages and DG
set currents under standard.
4) To effectively controlled power flow between source and
load.
5) The voltage-source converter (VSC) of BESS offers
reactive power compensation and maintains the balanced
DG currents. This reduces the vibration of shaft and over-
heating of machines.
6) It allows neutral current recompense using four leg VSC.
Nowadays, the fast increase in the use of nonlinear loads
such as computers, electronics appliances, medical
equipment, refrigerators, etc., has highlighted the concern
for power quality in the electrical distributionsystem.These
loads insert harmonics and distort the current and voltage
waveforms instigating poor power quality problems. The
imaginable provision for the mitigation of the power quality
difficulties is with presence of custom power devices while
meeting the standard. Three-phase four-wire loads are also
known to agonize from the problemofneutral currentdueto
nonlinearity and unbalance contemporary in the system.
This may harvest huge quantity of neutral current which
contains of triplen harmonics.
The neutral current may affect overloading of the
distribution system and causes extra heat losses, whichmay
be dangerous and poses a serious danger to the associated
equipment. A four-leg VSC is used for neutral current
compensation in addition to mitigate the current harmonics
with other described advantages.
Moreover, the flexible operation of the system becontingent
upon employment of the various control strategies. Some of
the control algorithms that have been pragmatic for
controlling are multi loop strategy, sliding-mode control, P-
controller-based technique, FLC-based control method, and
enhanced phase locked technique. The authors are un
successful to discuss the power quality and reactive power
compensation. The response of these controllers to the
unbalance and dynamic conditions is slow.
In this paper, an admittance-based control algorithm is
applied for the estimation of reference power component of
source currents in the PV-DG hybrid system.Theadmittance
of the load is projected using the active and reactive powers
of the load. The conductance (GL) and susceptance (BL) are
extracted from the predictable active power and reactive
power of the three-phase four-wire loads, respectively.
Nowadays, the rapid increase in the use of nonlinear loads
such as computers, electronics appliances, medical
equipment, refrigerators, etc., has emphasized the concern
for power quality in the electrical distributionsystem.These
loads inject harmonics and distort the current and voltage
waveforms causing poor power quality problems. The
possible provision for the mitigation of the power quality
problems is with inclusion of custom power devices [18]
while meeting the IEEE-519 standard. Three-phase four-
wire loads are also known to suffer from the problem of
neutral current due to nonlinearity andunbalancepresent in
the system. This may produce large amount of neutral
current which consists of triplen harmonics. The neutral
current may cause overloading of the distribution system
and causes additional heat losses, which may be dangerous
and poses a serious threat to the connected equipment. A
four-leg VSC is used for neutral current compensation in
addition to mitigate the current harmonics with other
reported advantages [19].
Additionally, the flexible operation of the system depends
upon implementation of the variouscontrol strategies.Some
of the control algorithms that have been applied for
controlling are multiloopstrategy[20],sliding-modecontrol
[21], P controller-based technique [22], FLC-based control
method [23], and enhancedphaselockedtechnique[24].The
authors have failed to discuss the power qualityandreactive
power compensation. The response of these controllers to
the unbalance and dynamic conditions is slow.
In this paper, an admittance-based control algorithm [25] is
applied for the evaluation of reference power component of
source currents in the PV-DG hybrid system.Theadmittance
of the load is estimated using the active and reactive powers
of the load. The conductance (GL ) and susceptance (BL ) are
extracted from the estimated active power and reactive
power of the three-phase four-wire loads,respectively.Itisa
simple mathematical formulation based on sinusoidal Fryze
current control. This control strategy is based on the
Lagrange’s multiplier method andthefundamental principle
of the PQ theory where thecomputationthroughtheClarke’s
transformation is eliminated. Therefore, it provides an
improvement in the math-ematical calculations. Here, the
inputs are the load currents (iL a , iL b , iL c ) and load
voltages (va , vb , vc ), which are further used for the
estimation of the active (p) and reactive (q) power
components using the formula mentioned in this paper. The
oscillating component of power is eliminated as it is passed
through the low-pass filter (LPF) to obtain Pd c and Qdc .
These are used for the estimation of the reference
conductance and susceptance, thus giving the value for the
reference active and reactive power components. This
method facilitates the extraction of the fundamental
components and compensates independently for the active
and reactive powers even when the system comprises of
harmonics and unbalances at the PCC. The compensation
allows balanced source currents to be drawn from the
network. The controller responds faster under the steady-
state and dynamic conditions. Thecontrol implementationis
realized using a four-leg VSC with admittance control

algorithm. The performance is verified experimental study
using digital signal processor (DSP-dSPACE) under both
linear and nonlinear loads.
It is a simple mathematical formulation created on
sinusoidal Fryze current control. This control approach is
based on the Lagrange’s multiplier method and the
fundamental principle of the PQ theory where the
computation through the Clarke’s conversion is removed.
Therefore, it delivers an enhancement in the mathematical
calculations. Here, the inputs are the load currents (iLa,
iLb,iLc )and load voltages (va , vb,vc), which arefurtherused
for the approximation of the active (p) and reactive (q)
power components using the formula stated in this paper.
The oscillating component of power is eliminated as it is
passed through the low-pass filter (LPF) to obtain (Pdc) and
(Qdc).These are used for the approximation of the reference
conductance and susceptance, thus giving the value for the
reference active and reactive power components.
This method enables the abstraction of the fundamental
components and compensates independently for the active
and reactive powers even when the system includes of
harmonics and unbalances at the PCC. The compensation
permits balanced source currents to be drawn from the
network. A D-STATCOM is added to the existing system to
reduce the harmonic further. The controller responds faster
beneath the steady-state and dynamic conditions. The
control employment is realized using a four-leg VSC with
admittance control algorithm.
LITERATURE SURVEY
Z. Jiang has acquainted on Global progress with sustainable
power source resources is appropriate to address the issue
for control in remote territories, which need grid and street
system. The help for the utilization of sustainable power
source resources is expanding as an unnatural weather
change is a noteworthy ecological concern, and it offers an
option for future vitality supply. Among the accessible
sustainable power source resources, sun basedphotovoltaic
(PV) control age is increasing wide acknowledgment, and it
is utilized for different applications, for example, family
machines, remotemissions,informationinterchanges,media
transmission systems, doctor's facilities, electric airplane,
and sun oriented autos.
A. Naik, R. Y. Udaykumar, and V. Kole, [2] The usageofthe PV
control age is for the reason that it has many favorable
circumstances, for example, it gives clean power, is compact
in nature, and can be utilized for different smallscale
Applications.
J. Philip et al., [3]. In any case, considering the substantial
changes in the yield of PV control, it is basic to incorporate
other power sources like a diesel generator (DG)set,battery
stockpiling, energy units, and so on. The execution
examination of independent systems with PV-and DG-based
sources.
J. Philip, B. Singh, and S. Mishra [4] the plan and operation of
independent DG-SPV-battery vitality stockpiling (BES)
utilizing a pinnacle identification based control approach.
J. Philip, B. Singh, and S. Mishra,[5] A charactertrianglework
(CTF)- based control approach and its examination for four-
wire independent dispersion system are illustrated.
J. Philip, B. Singh, and S. Mishra [6] An upgraded phase-
bolted circle (EPLL)- based control approach, whereinthree
EPLLs are utilized for extraction of major dynamic and
receptive power parts of load streams. In any case, just
recreation ponders are exhibited.
J. Philip, K. Kant, C. Jain, B. Singh, and S. Mishra, [7] A
composite onlooker basedcontrol approachforindependent
PV-DG-based system is utilized. Be that as it may, the
creators have given test comes about, however the control
approach is unpredictable and requires tuning of interior
parameters. Not at all like the control approach, the
proposed system utilizes a conductance-based basic control
approach. In addition, an itemized trial contemplate is
utilized to exhibit every one of the highlights of the system.
The proposed system comprises of a diesel-motor driven
lasting magnet synchronous generator (PMSG), PV exhibit,
and BES.
PROPOSED SYSYTEM
Fig. 1. Schematic diagram of the proposed system.
In this paper, an admittance-based control algorithm [25] is
applied for the evaluation of reference power component of
source currents in the PV-DG hybrid system. The induction
of the heap is assessed utilizing the dynamic and receptive
forces of the heap. The conductance (GL ) and susceptance
(BL) are removed from the evaluated dynamic power and
responsive energy of the three-phase four-wire loads,
separately. It is a basic numerical plan in view of sinusoidal
Fryze current control. This control system depends on the
Lagrange's multiplier strategy and the major standardofthe
PQ hypothesis Fig. 1. Schematic graph of the proposed
system. where the calculation through the Clarke's changeis
disposed of. In this manner, it gives a change in the
numerical computations. Here, the information sources are

the heap streams (iLa, iLb, iLc) and load voltages(va,vb,vc),
which are additionally utilized for the estimation of the
dynamic (p) and responsive (q) control parts utilizing the
recipe specified in this paper. The swaying part of energy is
dispensed with as it is gone through the low-pass channel
(LPF) to get Pdc and Qdc. These are utilized for the
estimation of the reference conductance and susceptance,
along these lines giving the incentive for the reference
dynamic and responsive power segments. This technique
encourages the extraction of the principal parts and repays
autonomously for the dynamic and receptive powers
notwithstanding when the system contains music and
unbalances at the PCC. The pay permits adjusted source
streams to be drawn from the system. The controller reacts
speedier under the enduring state and dynamic conditions.
The control execution is acknowledged utilizing a four-leg
VSC with induction control calculation. The execution is
confirmed exploratory investigation utilizing computerized
flag processor (DSP-dSPACE) under both straight and
nonlinear loads.
Solar PV Array
The PV exhibit is basically demonstrated with the
arrangement and parallel modules where insolation and
encompassing temperature goes about as info [26]. The
light-produced current of the PV cluster depends directlyon
the sunlight based illumination and is additionally impacted
by the temperature as appeared in Fig. 2. There are ten
modules in arrangement bringing about 205 V under open-
circuit condition and 100 modules are associated in parallel
for 30-A short out current in the PV cluster. The PV exhibit
has been furnished with a MPPT controller to work at the
most extreme power point (MPP) at any given temperature
and insulation level. The incremental conductance (IC)
calculation tracks the voltage and current at the most
extreme energy of the sunlight based [27].
SIMULATION RESULTS
The response of a standalone system is analyzed under
nonlinear load using sim power systemtoolboxinMATLAB/
SIMULINK. The performance of the system is observed
during line outage in one of the three phases at time t = 1.5 s
to 1.56 s, as shown in Fig7.4 (a)
.
Fig 2.MATLAB/SIMULINK Model for the proposed System
without DSATCOM
Fig 3.MATLAB/SIMULINK Model for the proposed System
with DSTATCOM
Fig.4 Wave forms of the Voltage & Current of the PMSG
Source
(a)

(b)
Fig.5 Performance of the proposed system under
unbalance nonlinear load, (a) Load Currents (Ila,Ilb,Ilc) (b)
Leakage currents (Icn,Isn,Iln)
The performance of the system is observed during line
outage in one of the three phases at time t= 1.5 s to 1.56 s, as
shown in Fig. It is observed that for a subjected load
unbalance in the system, the four-leg VSC has the capability
of harmonics elimination as the source currents and the
source voltages are maintained constantandneutral current
compensation is provided while maintaining a zero source
neutral current. The neutral currentcompensationprovided
by the four-leg VSC is clearly illustrated with the variations
in the load neutral current and VSC neutral current
waveforms.
Fig 6 THD values of Source Current
It is observed that for a subjected load unbalance in the
system, the four-leg VSC has the capability of harmonics
elimination as the source currents and the source voltages
are maintained constant and neutral current compensation
is provided while maintaining a zero source neutral current.
The neutral current compensation provided by the four-leg
VSC is clearly illustrated with the variations in the load
neutral current and VSC neutral current waveforms. The
system maintains its PCC voltage at the desired level.
Moreover, it should be noted that even during unbalanced
loading, the supply currents are balanced and sinusoidal
there by leading to balanced loadingontheDG,whichinturn
results in reduced maintenance and improved efficiency of
DG.
CONCLUSION
The induction based control method has been utilized for a
PV-diesel-battery hybrid system with a DSTATCOM for a
continuous power supply (UPS) and power quality change.
The incremental-based MPPTcalculationhasconveyed most
extreme sun oriented cluster control underunusual states of
temperature and insolation radiation. The technique has
been shown to dispose of sounds, stack adjusting,andtogive
nonpartisan current pay by joining four-leg VSC in the
system. The PCC voltage and recurrence have been looked
after steady. Attractive execution of the system has been
seen throughMATLAB/Simulationcomesaboutprocured for
unfaltering state and dynamic conditions under both
direct/nonlinear loads.
FUTURE SCOPE
This paper can be stretched out with Adaptive Neuro Fuzzy
Interface Systems (ANFIS) rather than PI Controller so that,
It can be decrease the Current THD Values, Improves the
Power Quality of the Proposed Systems.
REFERENCES
[1] F. Valenciaga and P. F. Puleston, “Supervisor controlfora
stand-alonehybrid generation system using wind and
photovoltaic energy,” IEEETrans. Energy Convers., vol. 20,
no. 2, pp. 398–405, Jun. 2005.
[2] C. Liu, K. T. Chau, and X. Zhang, “An efficient wind–
photovoltaichybrid generation system using doubly excited
permanent-magnet brushlessmachine,” IEEE Trans. Ind.
Electron., vol. 57, no. 3, pp. 831–839,Mar. 2010.
[3] W. Qi, J. Liu, X. Chen, and P. D. Christofides, “Supervisory
predictivecontrol of standalone wind/solar energy
generation systems,” IEEETrans. Control Syst. Technol., vol.
19, no. 1, pp. 199–207, Jan. 2011.
[4] F. Giraud and Z. M.Salameh,“Steady-stateperformanceof
a gridconnectedrooftop hybrid wind-photovoltaic power
system with batterystorage,” IEEE Trans. Energy Convers.,
vol. 16, no. 1, pp. 1–7,Mar. 2001.
[5] S.-K. Kim, J.-H.Jeon, C.-H.Cho, J.-B.Ahn, and S.-H. Kwon,
“Dynamicmodeling and control of a grid-connected hybrid
generation system withversatile power transfer,” IEEE
Trans. Ind. Electron., vol. 55, no. 4,pp.1677–1688,Apr.2008.
[6] M. Dali, J. Belhadj, and X. Roboam, “Hybrid solar–wind
systemwith battery storage operating in grid-connected and
standalone mode:Control and energy management—
Experimental investigation,” Energy,vol. 35, no. 6,pp.2587–
2595, Jun. 2010.

[7] W. D. Kellogg, M. H. Nehrir, G. Venkataramanan, and V.
Gerez, “Generationunit sizing and cost analysis for stand-
alone wind, photovoltaic,and hybrid wind/PVsystems,”IEEE
Trans. Energy Convers., vol. 13,no. 1, pp. 70–75, Mar. 1998.
[8] L. Xu, X. Ruan, C. Mao, B. Zhang, and Y. Luo, “An improved
optimalsizing method for wind-solar-battery hybrid power
system,” IEEE Trans.Sustain. Energy, vol. 4, no. 3, pp. 774–
785, Jul. 2013.
[9] B. S. Borowy and Z. M. Salameh, “Dynamic response of a
standalonewind energy conversion system with battery
energy storage toa wind gust,” IEEE Trans. Energy Convers.,
vol. 12, no. 1, pp. 73–78,Mar. 1997.
[10] S. Bae and A. Kwasinski, “Dynamic modeling and
operation strategy fora microgrid with wind and
photovoltaic resources,” IEEE Trans. SmartGrid, vol. 3, no.4,
pp. 1867–1876, Dec. 2012.
[11] C. W. Chen, C. Y. Liao, K. H. Chen, and Y. M. Chen,
“Modeling andcontroller design of a semiisolatedmultiinput
converter for a hybridPV/windpowerchargersystem,”IEEE
Trans. Power Electron., vol. 30,no. 9, pp. 4843–4853, Sep.
2015.
[12] M. H. Nehrir, B. J. LaMeres, G. Venkataramanan,V.Gerez,
andL. A. Alvarado, “An approach to evaluate the general
performance ofstand-alone wind/photovoltaic generating
systems,” IEEE Trans. EnergyConvers.,vol.15,no.4,pp.433–
439, Dec. 2000.
[13] W. M. Lin, C. M. Hong, and C. H. Chen, “Neural-network-
based MPPTcontrol of a stand-alone hybrid power
generation system,” IEEE Trans.Power Electron., vol. 26, no.
12, pp. 3571–3581, Dec. 2011.
[14] F. Valenciaga, P. F. Puleston, and P. E. Battaiotto,“Power
control ofa solar/wind generation system without wind
measurement: A passivity/sliding mode approach,” IEEE
Trans. Energy Convers., vol.18,no.4,pp.501–507,Dec.2003.
AUTHORS:
M.SOMNATH REDDY was pursuing
M.Tech from Shri Shirdi Sai Institute of
Science & Engineering, Anantapur, AP,
India.He is interested in Power
Electronics
M.RAVIKUMAR has 3 years experience
in teaching in post graduate level andhe
presently working as Assistant
professor in department of EEE, Shri
Shirdi Sai Institute of Science &
Engineering, Anantapur, AP, India.
J.CHINNAVANNUR SWAMY has 5 years’
experience in teaching in post graduate
level and he presently working as
Assistant professor in department of
EEE, Shri Shirdi Sai Institute of Science &
Engineering, Anantapur, AP, India.
P. A. PRABHAKARA. At present working
as an Assistant Professor and Headofthe
EEE Department in Shri Shirdi Sai
Institute of Science & Engineering,
Anantapur, AP, India.

Control and Implementation of a Standalone DG-SPV-BES micro-grid System using DSTATCOM

More Related Content

What's hot (18)

Similar to Control and Implementation of a Standalone DG-SPV-BES micro-grid System using DSTATCOM (20)

More from IRJET Journal (20)

Recently uploaded (20)

Control and Implementation of a Standalone DG-SPV-BES micro-grid System using DSTATCOM