DC Link Capacitor Voltage Stabilization of DFIG under various Fault Conditions
Keywords:wind energy conversion system (WECS), DFIG, PI controller, dc-link voltage, unsymmetrical fault, RSC, GSC
- Variable-speed Doubly Fed Induction Generator(DFIG) wind energy system is one of the main WECS
configurations in today’s wind power industry. The variable-speed operation is possible due to the power electronic
converters interface, allowing a full (or partial) decoupling from the grid. For a DFIG based wind energy system, the
rotor-side converter (RSC) controls the torque and active/ reactive power of the generator while the grid-side converter
(GSC) controls the DC-link voltage and its AC-side reactive power. The stability of DC link capacitor voltage is very
important in ensuring that a nearly sinusoidal voltage is delivered by the grid side converter which is used as inverter.
The fluctuations in the DC -link voltage cut down the lifetime and reliability of capacitors in voltage source
converters.The paper Deals with DC Link capacitor voltage stabilization under various types of faulty and load
conditions. In this Paper Variable Voltage source has been taken which represents a Fault that occurs in source wide
system. Due to this the Variable voltage source has been decreased to 0.5 Pu. So, Behaviour of DFIG system is studied in
this paper. The analysis is performed for normal, unsymmetrical fault and load conditions on DFIG integrated with grid
under MATLAB/ SIMULINK.