ELECTRICAL POWER QUALITY ENHANCEMENT OF GRID INTERFACED WITH WIND POWER SYSTEM USING STATCOM-CONTROL SCHEME

DEPARTMENT OF
ELECTRICAL ENGINEERING
Presentation on
Guide : Prof. Khan
Rahatullah
Presented By:
RATHOD MAMTA

 Introduction
 Aim and Objectives
 Power Quality Definition and standards
 Power Quality Issues and need for Power
Quality
 Power Quality Mitigation Techniques
 Literature Survey
 FACTS Device -STATCOM
 STATCOM With Battery Energy Storage
System
 Integration of wind turbine technology with
the grid

Proposed Topology for PQ Improvement
 Block Diagram of proposed system
 Control Scheme Parameter
 Proposed system Implementation on
MATLAB
 Outcomes
 Applications and Advantages
 Conclusion
 References

• Aim of electric power system: To generate electrical energy and to deliver
this energy to end-user equipment at an acceptable voltage
• Power quality is becoming important to electricity utilizing consumers at all
levels of usage
• In integration of power generation system with grid we will experience the
power quality problems
• The factors that are affecting power quality are voltage sag, voltage
variation, interruption, swells, brownout, distortions, Harmonic, noise,
voltage spikes, voltage flicker etc.
• The above problems may overcome by using compensation devices or
compensate load
• These devices include static compensator (STATCOM), Dynamic voltage
restorer (DVR), and unified power quality compensator (UPQC) to obtain
Better performance which is simulated by using MATLAB

• Our Aim is to study and implement the STATCOM-BESS
(Battery Energy Storage System) system and its impact on
the power quality in a system which consists of Wind Turbine
Generator (WTG), non-linear load, Bang-Bang controller for
monitoring the operation of STATCOM and grid connected
wind energy system
• The model is simulated in the MATLAB/Simulink
• This scheme mitigates the power quality issues, improves
voltage profile and also reduces Total Harmonic Distortions of
the waveforms

The PROPOSED SCHEME has the following objectives for
mitigation of Power Quality Issues:
• Reactive Power Compensation
• Implement Unity Power Factor at the PCC
• Make the source current sinusoidal
• Reduction of Total Harmonics Distortion
• Maintain Voltage Profile
• Implementation of Simple bang-bang controller for
STATCOM to achieve a fast and effective response

 Good power quality can be defined as a steady supply
voltage that stays within the prescribed range, steady AC
frequency close to the rated value, and smooth voltage
curve waveform
 The quality of electrical power may be described as a set of
values of parameters, such as:
 Continuity of service
 Variation in voltage magnitude
 Transient voltages and currents
 Harmonic content in the waveforms for AC power
 Power Quality = Voltage Quality, P = V I

 The International standards are developed by the working group of Technical
Committee-88 of the International Electro-technical Commission (IEC), IEC
Standard 61400-21 describes the procedure for determining the power quality
characteristics.
 Standards defining power quality are:
1. IEEE P1433: Power quality definitions
2. IEEE P1453: Voltage flicker
3. IEEE P1564: Voltage sag indices
4. IEEE 1159: Recommended practice for monitoring electric power quality
5. IEEE 519: Recommended practices and requirements for harmonic control in
electrical power system
6. IEC SC77A/WG9: Power quality measurement methods

 Reactive Power Demand
 Harmonic Distortion
 Voltage sags and swells
 Under voltages and over-voltages
 Voltage Unbalance
 Voltage Flicker
 Voltage Notching
 Voltage Interruption
 Transient Disturbances
 Frequency variations

Allows the equipment to run on optimal energy
consumption.
Saves your electricity bill
Reduces your overall energy consumption and therefore
your carbon footprint
Using optimized power reduces the risk of equipment
breakdown or overheating
Reduces the frequency at which maintenance work will be
required by minimizing the ‘wear and tear’ on machinery

A Flexible Alternating Current Transmission System (FACTS)
is used to enhance controllability and increase power transfer
capability of the network. In most of the applications the
controllability is used to avoid cost intensive.
TYPES OF FACTS DEVICES ARE
• SERIES DEVICES – SSSC, TCSC
• SHUNT DEVICES – STATCOM, SVC
• SERIES-SERIES DEVICES – IPFC, UPFC
• SERIES-SHUNT DEVICES – HVDC LINK

SR.NO NAME,
AUTHOR AND
YEAR
TITLE OF
PAPER
METHODOLOGY OUR REFERENCE
POINTS
1 Z. Yang, C. Shen, L.
Zhang, M. L. Crow,
and S. Atcitty, 2001
Integration of a
STATCOM and Battery
Energy Storage
This paper proposed control
strategies for voltage
control, dynamic stability, and
transmission capability
improvement, compared
simulation and
experimental results of an
integrated StatCom/BESS
system.
Enhancement of power
transmission system
operation by integrating a
Battery Energy Storage
System (BESS) into a
STATCOM
2 Tatsuto Kinjyo,
Tomonobu Senjyu,
Katsumi Uezato, Hideki
Fujita, and Toshihisa
Funabashi , 2004
Output Leveling of Wind
Energy Conversion
System by Current
Source ECS (Energy
Capacitor System)
This paper studied the power
storage system to promote
renewable energy and
proposed Current-Source ECS
(CS-ECS) to solve the issue of
conventional ECS to reduce
high internal-resistive loss of
EDLC cell
Compensate fluctuation of
the transmission power and
the WTG’s terminal bus
voltage respectively.
3 Kyungi Soo KOOK, Yilu
LIU, Stan ATCITTY ,
2006
Mitigation of the Wind
Generation Integration
Related Power Quality
Issues by Energy Storage
Illustrated the possible solution
to mitigate the integration
issues of the wind power by
application of the energy
storage to the wind farm in
power systems
Improving power system
stability is validated by
suppressing the power flow
fluctuation of the wind
farm

SR.NO NAME,
AUTHOR AND
YEAR
TITLE OF
PAPER
METHODOLOGY OUR REFERENCE
POINTS
4 J.J. Gutierrez, J. Ruiz,
L.A. Leturiondol, A.
Lazkanol, 2007
Flicker Measurement
System for Wind Turbine
Certification
This paper designed a flicker
measurement system that
meets the requirements
imposed by the standards
applicable to wind turbine
generator systems.
Assessment of power
quality in wind turbines in
accordance with the IEC
standard
5 Chong Han, Alex Q.
Huang, Mesut E. Baran,
Subhashish
Bhattacharya, Wayne
Litzenberger, Loren
Anderson, Anders L.
Johnson, and Abdel-
Aty Edris, 2008
STATCOM Impact Study
on the Integraion of a
Large Wind Farm into a
Weak Loop Power
System
The impact of Static
Synchronous Compensator
(STATCOM) to facilitate the
integration of a large Wind
Farm (WF) into a weak power
system was studied.
STATCOM control strategy
for voltage fluctuation
6 Sharad W. Mohod and
Mohan V. Aware, 2010
A STATCOM-Control
Scheme for Grid
Connected Wind Energy
System for Power
Quality Improvement”
In this proposed scheme STATic
COMpensator (STATCOM) is
connected at a point of
common coupling with a
battery energy storage system
(BESS) to mitigate the power
quality issues.
The STATCOM control
scheme for the grid
connected wind energy
generation system for
power quality
improvement.

• A Static Synchronous Compensator (STATCOM is a regulating
device used on alternating current electricity transmission
networks
• It is based on a power electronics voltage-source converter and
can act as either a source or sink of reactive AC power to an
electricity network
• It is inherently modular and electable
• STATCOM is installed to support electricity networks that have a
poor power factor and often poor voltage regulation

Fig.1- One-line diagram of
STATCOM
Fig. 2- STATCOM operation in power system

• The battery energy storage system (BESS) is used as an energy
storage element to support the wind farm during intermittencies
which also support grid during any disturbance and loss of
generation
• The BESS system is connected in parallel to the dc capacitor of
STATCOM
• The BESS will naturally maintain dc capacitor voltage constant
• It readily manages demand and supply of real power and also
injects or absorbed reactive power to stabilize the grid system

Load
kinetic
Energy
Mechanical
Energy
Electrical
Energy
Fig. 3- Wind Energy Generating System

• The STATCOM based current control voltage source inverter
injects the current into the grid in such a way that the source
current are harmonic free and their phase-angle with respect
to source voltage has a desired value.
• The injected current will cancel out the reactive part and
harmonic part of the load and induction generator current,
thus it improves the power factor and the power quality.

Fig. 4- Block diagram of proposed system

• STATCOM is interfaced with the BESS system.
• The STATCOM-BESS system is then connected to the PCC in the
grid where non-linear loads and induction generator based
wind turbine are also interfaced.
• Bang-Band current controller is adopted to control and
monitor the STATCOM –BESS system performance.
• This control strategy controls the output of STATCOM in such a
manner so as to achieve power quality and resolve other
power quality issues in the electrical grid.

 The control scheme approach is based on injecting
the currents into the grid using “bang-bang
controller.”
 The controller uses a hysteresis current controlled
technique.
 Using such technique, the controller keeps the
control system variable between boundaries of
hysteresis area and gives correct switching signals
for STATCOM.
 The control system scheme for generating the
switching signals to the STATCOM is shown in
Figure.

Fig.5- Control Scheme for System

 Hysteresis (Bang-Bang/On-OFF Controller) is a feedback
controller that switches abruptly between two states.
 These controller may be realized in terms of any element that
provides hysteresis.
Fig.6- of Bang-Bang Controller

• The proposed STATCOM with BESS is modeled and the transient performance
is studied by simulating in Simulink.
• The Simulink model consists of Wind energy system, Source, and Critical
load which is Asynchronous Generator.
• MATLAB parameters of following blocks are mentioned:
Sr. No Parameters Rating
1 Grid Voltage 3-Phase, 415V, 50hz
2 Asynchronous Induction
Generator
480V, 275KVA, 1800rpm
3 Line series Inductance 0.05e-3
4 Load Parameters 25KW
5 Inverter Parameters DC link Voltage = 800V DC link
Capacitance = 100µF Switching
frequency = 2kHz

Fig.7- Simulation Model without STATCOM

• A nonlinear load consisting of diode bridge is used for simulating the
system.
• The operation of the system without Controller and STATCOM is
carried out.
• The inverter is Switched ON at 0.1 s.
• The source current wave form is non-sinusoidal without
controller.
• THD analysis of source current without controller is practiced.
• The simulation of proposed system is carried out using Simulink and
the THD is found to be 24.62 % without STATCOM-Bang-Bang
controlled technique.

Fig. 8- THD Analysis without STATCOM

Fig. 9- Non-Sinusoidal Current Signal W/O STATCOM

• The simulation of proposed methodology has been carried out
using Simulink and the THD is found to be 24.62 % without the
Bang-Bang controlled technique.
• Non linear load distorts the grid current waveform and also
increase the harmonic component.
• Due to this, grid current is not in phase with the grid voltage
and its wave shape is also different from sine wave.
• Hence the power factor is not unity.
• Hence Power Quality is Disturbed.

Fig. 10- Simulation Model of Proposed System

Fig. 11- Simulation Model of Control System

 When STATCOM controller is made ON at t=0.5s, without change
in any other load condition parameters, it starts to mitigate the
reactive demand as well as harmonic current.
 The results of source current, load current and injected current
from STATCOM are in fig. 12(a), 12(b) and 12(c) respectively.
While Grid voltages and currents for Power Factor Improvement
and Reactive power Compensation are depicted in fig.(13)
 The DC link voltage regulates the supply current within the grid
connected wind energy generating system, that is the reason DC
link voltage is maintained constant across the capacitor as shown
in Fig. (14).

Fig .12- Source current, Load current and Injected current
(a)
(b)
(c)

ELECTRICAL POWER QUALITY ENHANCEMENT OF GRID INTERFACED WITH WIND POWER SYSTEM USING STATCOM-CONTROL SCHEME

It is observed that the source current on the grid is affected
due to the effects of non-linear load and wind generator, thus
purity of waveform may be lost on both sides in the system.
The source current without STATCOM operation is shown in
Fig (9).
Fig. 13- Power Factor Improvement and Reactive power Compensation

Fig.15- THD analysis without STATCOM

Fig. 16- THD Analysis With STATCOM Control Scheme

 Power system voltage control application
 Large electric arc furnace installation
 Reactive power compensation application
 Railway or underground system with huge load variation

The wind is free and with modern technology it can be
captured efficiently.
Uninterrupted power supply.
Wind power can go anywhere.
Wind power is cost effective

 To eliminate the harmonic content of the load current
the STATCOM-BESS control system is used
 Power quality is maintained at the point of common
Coupling
 Hysteresis current control scheme in the STATCOM is
used for the fast dynamic response
 It also maintains voltage and current in phase. That
means unity power factor is maintained at the source
end.

[1]Sharad W. Mohod and Mohan V. Aware, “A STATCOM-Control Scheme for Grid
Connected Wind Energy System for Power Quality Improvement” -IEEE
SYSTEMS JOURNAL, VOL. 4, NO. 3, SEPTEMBER 2010
[2]Mr.Ramesh Daravath and E.Deepika, “Power Quality Improvement In Grid
Connected Wind Energy System”- International Journal of Electronic and
Electrical Engineering. ISSN 0974-2174 Volume 8, Number 1 (2015), pp. 47-55,
International Research Publication House
[3]D. Srinivas , M. Rama Sekhara Reddy,” Power Quality Improvement in Grid
Connected Wind Energy System Using Facts Device and PID Controller”- IOSR
Journal of Engineering (IOSRJEN, Volume 2, Issue 11 (November 2012)
[4]G.Srinivas, 2T. Santosh Chaitanya,” POWER QUALITY IMPROVEMENT USING
FACTS DEVICE (STATCOM)” VOLUME-2, ISSUE-5, 2015
[5] Quoc-Nam Trinh and Hong-Hee Lee, “An Enhanced Grid Current
Compensator for Grid-Connected Distributed Generation Under Nonlinear
Loads and Grid Voltage Distortions”, IEEE TRANSACTIONS ON INDUSTRIAL
ELECTRONICS, 2013

ELECTRICAL POWER QUALITY ENHANCEMENT OF GRID INTERFACED WITH WIND POWER SYSTEM USING STATCOM-CONTROL SCHEME

More Related Content

What's hot (20)

Similar to ELECTRICAL POWER QUALITY ENHANCEMENT OF GRID INTERFACED WITH WIND POWER SYSTEM USING STATCOM-CONTROL SCHEME (20)

Recently uploaded (20)

ELECTRICAL POWER QUALITY ENHANCEMENT OF GRID INTERFACED WITH WIND POWER SYSTEM USING STATCOM-CONTROL SCHEME