This document describes an isolated wind-hydro hybrid power generation system using cage induction generators and battery storage. The system employs one squirrel cage induction generator driven by a variable speed wind turbine and another driven by a constant power hydro turbine. Both generators feed three-phase four-wire local loads. The system aims to improve power quality and efficiency for isolated locations with both wind and hydro potential. It demonstrates satisfactory performance under different electrical and mechanical dynamic conditions while maintaining constant voltage and frequency for the loads.

1. Isolated Wind–Hydro Hybrid
System Using Cage
Generators and Battery
Storage
GUIDE SUBMITTED BY
Dr.B.VENUGOPAL REDDY T.SINDHUJA(06641A0243)
M.DEEPIKA(09641A0241)
G.SUDHA(09641A0231)
N.KISHORE(09641A0253)

2. ABSTRACT
Isolated Wind–Hydro Hybrid System Using
Cage Generators and Battery Storage deals
with a new isolated wind–hydro hybrid
generation system employing one squirrel-cage
induction generator (SCIG) driven by a
variable-speed wind turbine and another SCIG
driven by a constant-power hydro turbine
feeding three-phase four-wire local loads.

3. EXISITNG SYSTEM LIMITS
• Renewable energy sources (solar) are the
natural energy resources that are inexhaustible.
• But there are many isolated locations which
cannot be connected to the grid and where the
wind potential and hydro potential exist
simultaneously.

4. WIND-HYDRO HYBRID SYSTEM MERITS
Among the renewable energy sources, small
hydro and wind energy have the ability to
complement each other.
Control algorithm for the VSCs are to achieve
maximum power tracking (MPT) through rotor
speed control of a wind-turbine-driven SCIG
under varying wind speeds and control of the
magnitude and the frequency of the load voltage.
Improve the power quality.
System efficiency increases.

5. HYDRO POWER

6. WIND POWER

7. CIRCUIT DIAGRAM

8. OPERATION
• Hydroelectric plants convert the kinetic energy of a
waterfall into electric energy. The power available in
a flow of water depends on the vertical distance the
water falls (i.e., head) and the volume of flow of
water in unit time (i.e., discharge).
• The water powers a turbine, and its rotational
movement is transferred through a shaft to an electric
generator. When SCIG is used for small or micro
hydro applications, its reactive power requirement is
met by a capacitor bank at its stator terminals.

9. Squirrel cage induction
generator
• In Conventional, directly grid coupled squirrel
cage induction generator, the slip varies and
hence the rotor speed of a squirrel cage
induction generator varies with the amount of
power generated.
• These rotor speed variations are, however, very
small, approximately 1 to 2 per cent.
• Therefore ,this wind turbine type is normally
referred to as a constant speed or fixed speed
turbine.

11. Pulse-width modulation
 pulse-width modulation (PWM), is a commonly
used technique for controlling power to inertial
electrical devices, made practical by modern
electronic power switches.
 The simplest way to generate a PWM signal is the
intersective method, which requires only a saw
tooth or a triangle waveform (easily generated
using a simple oscillator) and a comparator. When
the value of the reference signal is more than the
modulation waveform ,the PWM signal (magenta)
is in the high state, otherwise it is in the low state.

13. Battery energy storage system (BESS).
The advantage of using BESS on the dc bus of the
PWM converters is that no additional converter is
required for transfer of power to or from the battery.
 Further, the battery keeps the dc-bus voltage constant
during load disturbances or load fluctuations.

14. ZIGZAG TRANSFORMER
• A zigzag transformer is connected in parallel to the
load for filtering zero-sequence components of the
load currents. Further, the zigzag windings trap triple
n harmonic (third, ninth, fifteenth, etc.) currents.
• The zigzag transformer is to be located as near to the
load as possible. The neutral terminal of the consumer
loads is connected to the neutral terminal of the
zigzag transformer.

15. Control scheme of machine-side converter

16. Control scheme of load-side converter

17. Performance of hybrid system with balanced
linear load at wind speed of 11 m/s.

18. 3 phase load voltage and load current

19. CONCLUSION
 Among the renewable energy sources, small hydro and wind
energy have the ability to complement each other. Further,
there are many isolated locations which cannot be connected to
the grid and where the wind potential and hydro potential exist
simultaneously.
 The performance of the this hybrid system has been
demonstrated under different electrical (consumer load
variation) and mechanical (with wind-speed variation)
dynamic conditions. It has been demonstrated that the hybrid
system performs satisfactorily under different dynamic
conditions while maintaining constant voltage and frequency.

20. THANK U

21. • With some other types of semiconductor
device such as the insulated-gate bipolar
transistor (IGBT), both turn-on and turn-off
of thyristor can be controlled .
• As a result, IGBTs can be used to make self-
commutated converters. In such converters,
the polarity of DC voltage is usually fixed
and the DC voltage, being smoothed by a
large capacitance, can be considered
constant.