• M.SHIRISHA

In the wind generation system, the variable-speed generation system is more attractive than the fixed-speed system because of the improvement in wind energy production and the reduction of the flicker problem by the variable-speed generation. The proposed method can not only detect the fault condition but also identify the location of the faulty switch. In the proposed method, this is designed by incorporating a simple switching control in the conventional method. By using the closed-loop control systems, an analysis of the system discloses that it is possible for signal energy to traverse different paths and to be modified in a different manner in these various paths without using additional sensors or performing complex calculations. The reasons for using multiple-loop systems are many that is Improved linearization, noise reduction, and change in impedance level can be achieved by using auxiliary loops. It is also possible to synthesize certain transfer functions by using additional feed-back paths. For the fault detection of the NPC-type rectifier, the fault detection method which uses a dc-link voltage with a grid angle is proposed. The proposed tolerant Control maintains normal operation with sinusoidal currents under the open-circuit fault of outer switches by adding a compensation value to the reference voltages. Three-level topologies are widely used in back-to-back converters of wind turbine generation systems. Simulations and experiments are carried out to confirm the reliability of the proposed fault-detection method.

Neutral-point-clamped rectifier, open-circuit fault, open-switch fault, reliability, three-level topology, tolerant control, T-type rectifier.

"ENHANCEMENT OF OPEN CIRCUIT FAULT IN OUTER SWITCHES OF THREE LEVEL RECTIFIERS IN WIND TURBINE SYSTEMS USING FAULT TOLERANT CONTROL METHOD", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.4, Issue 11, page no.96-104, November-2017, Available :http://www.jetir.org/papers/JETIR1711017.pdf

"ENHANCEMENT OF OPEN CIRCUIT FAULT IN OUTER SWITCHES OF THREE LEVEL RECTIFIERS IN WIND TURBINE SYSTEMS USING FAULT TOLERANT CONTROL METHOD", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.4, Issue 11, page no. pp96-104, November-2017, Available at : http://www.jetir.org/papers/JETIR1711017.pdf