Now a days we are facing so many problems with power quality issues. So in order to mitigate these problems and to improve the power quality we are using new STATCOM control scheme in wind farm.

1. BY
Y. SANNUTHI
New STATCOM control scheme
for Power Quality improvement
in wind farm

2. ABSTRACT
 The influence of the wind turbine in the grid system concerning the power
quality measurements are-the active power, reactive power, variation of
voltage, flicker, harmonics, and electrical behavior of switching operation
and these are measured according to national/international guidelines.
 This project demonstrates new control scheme for STATIC
COMPENSATOR(STATCOM) which is connected at a point of common
coupling with a battery energy storage system (BESS) to mitigate the power
quality issues.

3. INTRODUCTION
 Renewable energy resources are receiving considerable attention in the
continued growth and development of electric power systems, being the
wind power production the fastest growing type of renewable energy.
 During the normal operation, wind turbine produces a continuous variable
output power.
 These power variations are mainly caused by the effect of turbulence, wind
shear, and tower-shadow and of control system in the power system.Thus,
the network needs to manage for such fluctuations.
 The STATCOM is shunt connected at the bus where the wind turbine is
connected to the power network to provide voltage regulation and improve
the short-term transient voltage stability. The STATCOM control schemes
are suitably designed and coordinated.

4.  WIND ENERGY GENERATING SYSTEM
 FACTS
• STATCOM
 BESS
COMPONENTS

5. WIND ENERGY GENERATING SYSTEM
Non linear
loads
kinetic
Energy
Mechanical
Energy
Electrical
Energy
wind Wind turbine Induction
generator
Grid Non- linear
load

6. POWER QUALITY
 Power quality mainly deals with,
• Continuity of power supply.
•“Quality” of the voltage.
“POWER QUALITY” maintenance is an important aspect in the
economic operation of a system.
Various “POWER QUALITY ”problems may leads to another
undesirable problems.

7. POWER QUALITY ISSUES
 Wind Turbine Location In Power System
 Voltage variations
 Harmonics
 Flickers

8.  FACTS – Flexible AC Transmission system.
 Used to enhance controllability and increase power transfer
capability."
FACTS

9.  It is a regulating device
used on AC transmission
networks.
 It acts in either capacitive or
inductive mode.
 It is based on a voltage-
source converter.
STATCOM

10.  Voltage-Source Converter converts voltage and currents from
DC to AC while the exchange of power can be in both
direction.
 From AC to DC (rectifier mode).
 From DC to AC (inverter mode).
 Mainly 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.

11.  It is used for the purpose of voltage regulation.
 It can be used to level the power fluctuation by charging and
discharging operation.
 It rapidly injects or absorbed reactive power to stabilize the grid
system.
BATTERY ENERGY STORAGE
SYSTEM(BESS)

12. CONTROL SCHEME
It is based on injecting the currents into the grid using
“Bang-Bang controller.”
 It gives correct switching signals for STATCOM
operation.

13. BLOCK DIAGRAM

14. POWER NETWORK MODEL OF GRID CONNECTED
SYSTEM

15. 3PH SOURCE
V I
RL BRANCH
STATCOM BREAKER
LOADV I
WIND TURBINE
ASYN-GEN
PF CORRECTION
FILTER CONTROLLER
GAIN
UNIT VECTOR
RELAY
NOT
SIMULATION DIAGRAM

16. SIMULATION RESULTS
Source voltage wave form
Simulation diagram of Source voltage

17. Source current waveform
 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.
Simulation diagram of source current

18. Simulation diagram of STATCOM injecting current
 The compensated current for the Non-Linear load and demanded Reactive
Power is provided by the Inverter.
 The Real Power Transfer from the Batteries is also supported by the
Controller of this Inverter.
STATCOM injecting current wave form

19. Simulation diagram of load current
load current waveform
WITHOUT STATCOM WITH STATCOM

20. Supply Voltage and Current at PCC.
 The source current with and without STATCOM operation is shown in Fig.
 The Unity Power factor is maintained for the source Power when the STATCOM
is in operation.
Simulation diagram of Supply Voltage and Current at PCC
WITHOUT STATCOM WITH STATCOM

21. THD% at PCC with STATCOM

22.  The Power Quality issues and its consequences are presented.
 STATCOM has a capability to cancel out the Harmonic parts of
the Load Current.
 STATCOM maintains the Source Voltage and Current in-Phase
and support the Reactive Power demand for the Wind Generator
and load at PCC.
CONCLUSION