Contents
How does Dfig control reactive power?
The instantaneous active and reactive power (Ps, Qs) of the DFIG stator can be controlled independently by the RSC as shown in Fig. 2(a). Regulating the DFIG terminal voltage can be achieved by using the stator side reactive power. Both converters can be modelled as current controlled voltage source converters.
What is DFIG system?
The doubly-fed induction generator (DFIG) system is a popular system in which the power electronic interface controls the rotor currents to achieve the variable speed necessary for maximum energy capture in variable winds.
What is the function of rotor side converter of a Dfig?
The back-to-back converter is connected to the rotor of the DFIG, and its purpose is to feed the rotor with currents of varying frequency, in order to reach the desired rotor speeds.
Why do we use Dfig?
DFIG wind turbine also improves system efficiency with its optimal rotational speed, reduces noise and mechanical stresses, improves power quality, and compensates for torque and power pulsations [1].
What are the application of Dfig?
Double-fed induction generator (DFIG), a generating principle widely used in wind turbines. It is based on an induction generator with a multiphase wound rotor and a multiphase slip ring assembly with brushes for access to the rotor windings.
What is the function of Gridside converter?
The grid-side converter is used to adjust the voltage of the capacitor and the d-axis and q-axis currents. The control structure of the grid-side converter shown in Fig. 9.60 includes an outer loop to adjust the DC-link voltage.
What is the function of rotor side converter?
Explanation: The function of rotor side converter is to control the generator. It controls the generator in terms of active and reactive power by ensuring minimum power loss during power conversion.
How is the dynamic model of DFIG controlled?
The dynamic model of DFIG depends upon the non-linear parameters such as electromagnetic torque, stator current; rotor current and stator flux are controlled with state feedback linearization techniques to get the better results as compared to the exit method ( Baroudi et al., 2007, Hu et al., 2010 ).
How is power control used in DFIG wind turbines?
The control approach is estimated through the simulation result of the feedback controller assembled with DFIG wind turbines. It is applied by the feedback control based techniques in order to control the power flowing of DFIG and the power grid.
Why do we need active and reactive power control?
Implementation of DFIG is increasing for many reasons, such as reducing the mechanical stress, to mitigate the noise, and flexible control of the active and reactive power on the basis of back to back converter between the induction machine and the power grid ( Mishra et al., 2009, Rahimi, 2016 ).
What is the theoretical limit for power coefficient?
Power coefficient is a function of wind turbine speed. is 0.59 the theoretical limit, but practical range is 0.2–0.4 ( Patel, 2005 ).