Worldwide wind turbines have steadily increased. They are very different in nature from conventional
generators.
Induction generators in large scale are used in wind turbines for their simple construction and reliable
operation.
With the increase
in penetration of wind turbines, the power system dominated by synchronous
machines will experience a change in dynamics and operational parameters.
This paper aims to analyze the impact of induction generators on transient and small signal stability of
power systems by gradually increasing the rate of power generated by wind turbines and changing the
location of these turbines in the power system.
The turbine control purpose is to achieve the maximum limit of wind power,
associated with reducing the mechanical loads. The current control techniques do not take
into consideration the dynamical side of wind and turbine, which leads to power los
s. To
improve the effectiveness of the
nonlinear controllers, we can derive the nonlinear feedback controllers for static and
dynamic conditions in order to reach the wind speed estimator. Then we can test the
controllers by a mathematical model applied on the wind turbine simulator, with
disturbances and noise. The results have shown important improvements in comparison
with the current used controllers.
This study treat the effect of the Suction method as a way of the
boundary layer controlling in order to avoid or at least delay the
boundary layer separation and to explain the effectiveness of this
method in improving the aerodynamic performance
of the
Airfoils of the studied wind turbine blade and thus the possibility
of obtaining better electrical output of the wind turbine, that is
performance improving of wind turbines and obtains a better
design.
This paper presents a new contribution the domain of sensorless speed control of
doubly-fed induction generator in wind turbine applications. Where the speed and the
dynamic torque are estimated and used to feedback the control loops. The proposed
sensorless algorithm is robust to variations of the values of machine parameters where the
estimated speed is independent of them. The algorithm avoids using differentiation which
significantly improves its immunity to noise. The field oriented vector control theory is
used to control the speed of the doubly fed induction machine. The used controllers in
closed loops are classical proportional integral (PI). The modeling is based on the Park
equations of the induction machine and on a simple model of the three phase inverter. The
results of simulink on MATLAB provide good performance of the sensorless speed
control.
reliance on new and renewable sources of energy has grown in order to obtain
electric power without the use of traditional fossil fuel sources. And thus solve
the problems of the global energy crisis and also maintain a clean environment,
through
the fight against the dangers of global warming and its negative results
Wind power is considered as one of the most important of these alternative
energies.
We will work in this research in order to be able to control wind turbine with
variable speed through pitch angle control in order to organize power and
control the rotational speed in order to make the power ideal.
Where we will be using a fuzzy controller to control pitch angle instead of the
traditional controllers, which is expected to improve system response and
provide ease in the application and modification and reduction in the cost.
By reference study we came to the result showing that most previous studies in
advanced wind energy systems have addressed to control wind turbine using
conventional controllers from PI or PID type. Show we have the problem of the
need to know the exact mathematical model of the system. Where traditional
controllers of wind turbines that operate at variable speed are based on
mathematical models which may be complex and non-linear and neglect often
physical phenomena, for example, magnetic saturation which leads to
complexity in the calculation and unexpected performance of the driven system.
The proposed research aims to provide a complete study through modeling and
simulation using the Matlab about the use of fuzzy controller to control the
wind turbine where traditional controllers of type PI will be designed to control
the pitch angle and to control the rotational speed and fuzzy PI controllers to
control the pitch angle. Results will be get and discussed and conclusion will be
extracted from them.
Research Results showed that the fuzzy control improves transient state
behavior, but the steady-state behavior is better controlled when we use PI
controller. So and based on the result we got, the PI controller can't be replaced
actually with the fuzzy controller.