الفهرس 
Fixed-speed wind turbine generatorsOnly 14 pages are availabe for public view
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Abstract
6.1 An effective technique using SFCL for improving the FRT capability of the DFIG-based wind turbines was proposed. SFCL provides zero impedance during normal operation and exhibits increased impedance under fault conditions. So, SFCL was integrated with the DFIG-based wind turbines to enhance its performance during grid faults. The considered type of SFCL was resistive type due to its simplicity and compact size. Modeling of both the SFCL and the DFIG-based wind turbine was implemented using PSCAD/EMTDC software. It was concluded that: SFCL is able to limit the stator short circuit current during a three phase fault at the grid side to about 50% of its value without SFCL. This limitation is reflected also to the rotor currents as a result of the magnetic coupling. Though, protection of the converter is achieved using the proposed technique without any additional protection devices in the rotor circuit. A great enhancement of the voltage profile of the machine was achieved during the three phase fault. The voltage dip is decreased to levels which comply with most grid codes. The dynamic performance of the generator, which is reflected on the active and reactive power, showed a significant improvement. Connecting the SFCL keeps the delivery of active power to the grid instead of zero delivered power without connecting the SFCL. The amount of the reactive power absorbed from the grid to recover from the fault is decreased significantly by using the SFCL, which improves the overall stability of the system.