ISSN(Online): 2319-8753
ISSN (Print): 2347-6710
International Journal of Innovative Research in Science,
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Vol. 7, Issue 5, May 2018
SVC and STATCOM for Reactive Power
Compensation in Transmission Line
Priyanka G Patel1, Gaurang Patel2, Dr. Ami T. Patel3
P.G. Student, Department of Electrical Engineering, MGITER Engineering College, Navsari, Gujarat, India1
Assistant Professor, Department of Electrical Engineering, MGITER Engineering College, Navsari, Gujarat, India2
Assistant Professor, Department of Electrical Engineering, Government Engineering College, Bharuch, Gujarat, India3
ABSTRACT: This research study focus on the comparative analysis of reactive power compensation technologies.
Static VAR Compensator (SVC) is one of the shunt connected FACTS device which is to be utilized here for the
purpose of reactive power compensation. A Static Synchronous Compensator (STATCOM) is used to improve the
voltage profile of the load bus.
KEYWORDS: facts devices, reactive power compansation, svc, statcom.
I. INTRODUCTION
Reactive power compensation is a means for realizing the goal of a qualitative and reliable electrical power system.
Reactive power compensation is a technique for the compensation of the unwanted effects of reactive loads which
makes the power factor less than unity. With the reactive power compensation techniques, reactive power is controlled
in such a way that the performance of electric power system such as improvement of transmission efficiency, harmonic
loss reduction and power quality improvement gets improved.
There are two viewpoints to the issue of reactive power remuneration: load remuneration and voltage support. Load
remuneration comprises of change in force component, adjusting of genuine force taken from the supply, good voltage
regulation, and so on of extensive changing burdens. Voltage bolster comprises of decrease of voltage change in a
transmission line. These types compensation can be realized in two ways: series and shunt compensation. These adjust
the parameters of the framework to give improved VAR compensation. Shunt compensation is one where capacitors
are employed in parallel with the transmission line and act like a synchronous condenser and absorb or supply reactive
power. A series is one where inductor or capacitors are employed in series to supply required power. Mostly shunt
compensation are employed nowadays in FACT devices.
II. RELATED WORK
Synchronous Phase Modifier
This is an ideal source having the capacity either to absorb or inject reactive power. However, it has got number of
limitations as pointed out in section 1.5 (performance requirement). There are proven alternative methods of
compensation available which are practically equivalent to SPM at low cost, more reliable, fast in response and giving
trouble free service.
Shunt Capacitors
The use of shunt capacitors in conventional way through mechanical switches has the following:
Overall cost is very low.
The installation is simple requiring no strong foundations.
Incur negligible losses
Less maintenance problems
More reliable in service with long life. However, notable short coming are:
Copyright to IJIRSET DOI:10.15680/IJIRSET.2018.0705067 4880
ISSN(Online): 2319-8753
ISSN (Print): 2347-6710
International Journal of Innovative Research in Science,
Engineering and Technology
(A High Impact Factor, Monthly, Peer Reviewed Journal)
Visit: www.ijirset.com
Vol. 7, Issue 5, May 2018
Not possible to vary reactive power matching with load demand continuously (only step variation).
There exist a possibility for harmonics, if present, to get amplified.
There also exists a scope for series / parallel resonance phenomenon to occur, which requires to be
investigated prior hand. Hence the choice of a suitable compensator scheme calls for detailed study and careful
design before implementation.
Series Capacitors
it poses serious problems during faults, prone for resonance phenomenon, complexity in control and likely to give rise
to sub-synchronous oscillations. Hence the series capacitors can be installed after careful study only. They are
employed widely in HV lines and somewhat uneconomical for distribution networks, as the requirements in both cases
differ widely.
III. FACTS DEVICES
Flexible AC Transmission (FACT) devices are static equipments which helps in not only for compensating reactive power but also
control one or more AC transmission parameters. Flexible AC Transmission Devices includes Static synchronous compensator,
Thyristor switched reactor, Static synchronous series compensator, Thyristor switched capacitor, Thyristor switched series reactor.
Depending on the power electronic devices used in power system, the FACTS controllers can be classified as
Variable impedance type.
Voltage Source Converter (VSC).
Variable impedance controllers include:
• Static Var Compensator (SVC), (shunt connected)
• Thyrister Controlled Series Capacitor or compensator (TCSC), (series connected)
• Thyristor Controlled Phase Shifting Transformer (TCPST)
• PST (combined shunt and series)
The VSC based FACTS controllers are:
• Static synchronous Compensator (STATCOM) (shunt connected)
• Static Synchronous Series Compensator (SSSC) (series connected)
• Interline Power Flow Controller (IPFC) (combined series-series)
• Unified Power Flow Controller (UPFC) (combined shunt-series)
IV. SVC CONTROLLER
The two main popular configuratin of this type of shunt controller are the fixed capacitor (FC) with a thyristor controlled reactor
(TCR) and the thyristor switched capacitor (TSC). In its simplest form, the SVC consists of a TCR in parallel with a bank of
capacitors. From an operational kind, the SVC behaves like a shunt-connected variable reactance, which can generates or absorbs
reactive power in order to regulate the voltage magnitude at the point of connection to the AC network.
Fig 1:Statcom controller
Copyright to IJIRSET DOI:10.15680/IJIRSET.2018.0705067 4881
ISSN(Online): 2319-8753
ISSN (Print): 2347-6710
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Vol. 7, Issue 5, May 2018
A static synchronous compensator (STATCOM), also known as a "static synchronous condenser" ("STATCON"), is
regulating mechanism used on alternating current electricity transmission networks. It is based on the power electronics
voltage-source converter and can act as either a source or sink of reactive AC power to an electricity network. If it is
connected to a source of power it can also provide active AC power. That is a member of the FACTS family of devices.
fig 2: statcom controller
V. V-I CHARACTERISTIC OF SVC AND STATCOM
The operating Principle of both the FACT Devices are different, both of the devices are used for the improvement of
power system stability. Fig shows the operating characteristics of both the FACT Devices the STATCOM has the
capability to maintain the full capacitive current even at low system voltage while the SVC has the absent of same
characteristics. This ability make the STATCOM more effective than the SVC in the improvement of power system
stability.
Fig 3: vi characteristic of svc and statcom
VI. MATHEMATICAL FORMULATION
Static Synchronous Compensator is one of the static component device and comes under the family of FACTS devices.
It can absorb or supply reactive power in the single or three phase AC systems. A transmission network reactive power
can be compensated using Static Synchronous Compensator. It also helps in preventing fluctuations in the transmission
system like sudden voltage increase (voltage sag), sudden voltage decrease (voltage sag), transients etc.
A STATCOM comprises of a three phase inverter utilizing SCRs, MOSFETs or IGBTs, a DC capacitor (which when
charging will absorb reactive power and while discharging will supply reactive power), a connection reactor whose
purpose is to link the inverter output to the AC supply side, channel parts to channel out the high recurrence segments
Copyright to IJIRSET DOI:10.15680/IJIRSET.2018.0705067 4882
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Vol. 7, Issue 5, May 2018
because of the PWM inverter. From the DC side capacitor, a three stage voltage is produced by the inverter. This is
synchronized with the AC supply. The connection inductor interfaces this voltage to the AC supply side. This is the
essential standard of operation of STATCOM.
Where: P= Instantaneous Power
Vmax=Maximum Voltage
Imax=Maximum Current
W=Angular Frequency
T=Time period
Ө=Angle between Voltage and Current
VII. RESULT & DISSCUSSION
A static var compensator (SVC) is used to regulate voltage on a sytem .When system voltage is low the SVC generates
reactive power (SVC capacitive). When system voltage is high it absorbs reactive power (SVC inductive). km
transmission line is used.
A positive value of SVC susceptance indicates that the SVC is capacitive and a negative value indicates inductive
operation.
Fig 4 :simulation with svc
The SVC is rated +100 Mvar capacitive and 50 Mvar inductive. The two500 kV Three-Phase Programmable Voltage
Source is used to vary the system voltage to observe the SVC performance. The SVC is set in voltage regulation mode
Copyright to IJIRSET DOI:10.15680/IJIRSET.2018.0705067 4883
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ISSN (Print): 2347-6710
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Vol. 7, Issue 5, May 2018
with a reference voltage Vref=1.0 pu. The voltage droop is 0.03 pu/100MVA, so that the voltage varies from 0.97 pu to
1.015pu when the SVC current goes from fully capacitive to fully inductive.
fig 5: simulation model for statcom
VIII. SIMULATION RESULT WITH SVC & STATCOM
Reactive Power Comparisons at B1
-20
With SVC
-40 With STATCOM
-60
ReactivePower
-80
-100
-120
-140
-160
-180
0 0.2 0.4 0.6 0.8 1
Time, Sec
fig 6: reactive power waveform at b1
Initially the source is generating nominal voltage. Then, voltage is successively decreased (0.97 pu),increased (1.018pu)
and finally returned to nominal voltage (1 pu). A positive of Q(pu)value in dicates inductive operation and a negative
value of Q(pu) value indicates capacitive operation.
Copyright to IJIRSET DOI:10.15680/IJIRSET.2018.0705067 4884
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ISSN (Print): 2347-6710
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Vol. 7, Issue 5, May 2018
At B1
Reactive Power Comparisons at B2
0
-50 With SVC
With STATCOM
Reactive Power
-100
-150
-200
-250
0 0.2 0.4 0.6 0.8 1
Time, Sec
Fig 7: reactive power waveform at b2
During the 10-cycle fault, a key difference between the SVC and the STATCOM may be observed. The reactive power
is generated by the SVC is -0.48 pu and the reactive power generated by the STATCOM is -0.71 pu.
Reactive Power Comparisions at B3
0
-50
Reactive Power
With SVC
-100 With STATCOM
-150
-200
0 0.2 0.4 0.6 0.8 1
Time, Sec
Fig 8: reactive power at b3
IX. CONCLUSION
Run the simulation and look at results. Result displays the measured reactive power Qm generated by the SVC
(magenta trace) and the STATCOM. During the 10-cycle fault, a key difference between the SVC and the STATCOM
may be observed. The reactive power is generated by the SVC is -0.48 pu and the reactive power generated by the
STATCOM is -0.71 pu.
Copyright to IJIRSET DOI:10.15680/IJIRSET.2018.0705067 4885
ISSN(Online): 2319-8753
ISSN (Print): 2347-6710
International Journal of Innovative Research in Science,
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Vol. 7, Issue 5, May 2018
We can then see that the maximum capacitive power generated by a SVC is proportional to the square of the system
voltage while the maximum capacitive power generated by a STATCOM decreases linearly with voltage decrease
(constant current). This ability is to provide more capacitive power during a fault is one important advantage of the
STATCOM over the SVC. Moreover, the STATCOM will normally exhibit a faster response than the SVC because of
the presence of Voltage Source Convertor.
APPENDIX
SVC DATA:
Converter rating : 100 MVA
System nominal voltage: 500 KV
Reactive power limits: Qc(var>0)= 100 Mvar
Reactive power limits: Ql(var<0)= -100 Mvar
Average time delay due to thyristor valves firing Td : 4 ms
STATCOM :
Converter rating : 100 MVA
System nominal voltage: 500 KV
Converter impedance: R= 0.0073 pu L= 0.22 pu
Converter initial current: Magnitude=0 pu Phase angle =0 deg
DC link nominal voltage : 40 KV
DC link equivalent capacitance : 375 Uf
REFERENCES
[1] M.Gerald Geafori Titus, “Reactive Power Compensation using STATCOM for single phase distribution system “, 2015 International Conference
on on Circuit, Power and Computing Technologies, ICCPCT-2015
[2] Mohammed Benidris, Samer Sulaeman, “Reactive Power Compensation for Reliability Improvement of Power Systems”, IEEE Transactions,
2016
[3] Famous. O. Igbinovia, Ghaeth Fandi, Jan Švec, Zdenek Müller, Josef Tlusty, “Comparative Review of Reactive Power Compensation
Technologies”, IEEE Transactions, 2015
[4] Piyushkumar M. Saradva, Mahesh H. Pandya, “Reactive and Real Power Compensation in Distribution Line using D-STATCOM with Energy
Storage”, 2016 International Conference on Computation of Power, Energy Information and Communication (ICCPEIC), IEEE
[5] Brij Sunder Joshi, Om Prakash Mahela, Sheesh Ram Ola, “Reactive Power Flow Control Using Static VAR Compensator to Improve Voltage
Stability in Transmission System “, IEEE International Conference on Recent Advances and Innovations in Engineering (TCRAIE-2016), December
23-25, 2016, Jaipur, India
[6] Ahmed H. Al-Mubarak; Muhammad Haris Khan, Moayed Z. Al-Kadhem, “Dynamic Reactive Power Compensation For Voltage Support Using
Static Var Compensator (SVC) In Saudi”, IEEE Transactions, 2015
[7] S.K.Das and J.K.Moharana, “Design, Analysis and Simulation of Small Signal Control Strategy of a STATCOM for Reactive Power
Compensation on Variation of DC link Voltage”, 2013 International Conference on Power, Energy and Control (ICPEC)
[8] Hui Li, Shucai Li, Hao Zhang, “Study of STATCOM on Reactive Power Compensation Strategy of Wind Farm”, 2013 International Conference
on Computer Sciences and Applications
[9] Tang Aihong, Guo Fang, Liu Furong, Chen Yuepeng, “Mathmatical model of STATCOM based on switched System”, IEEE Transactions, 2011
[10] A. K. Pathak, Dr. M. P. Sharma, Dr. Manoj Gupta, “Modeling and Simulation of SVC for Reactive Power Control in High Penetration Wind
Power system”, IEEE INDICON 2015
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