Wind energy conversion system control robustness based on current analysis of IGBT open-circuit fault

摘要

This paper deals with the study of the performance of a wind energy conversion system (WECS) based on a doubly fed induction generator (DFIG) under the IGBT open-circuit fault of the rotor side converter (RSC) during the application of robust control techniques, such as backstepping control (BSC) and sliding mode control (SMC). The presence of IGBT open-circuit faults in DFIG-WECS can disrupt service continuity resulting in financial loss. To overcome such a problem, robust control techniques are usually used as a solution. These control techniques are well known for their ability to treat non-linear structures as power electronics converters and to maintain the performance and stability of the DFIG-WECS connected to the network by the back-to-back converter in healthy and faulty operations. The aim of using robust non-linear control techniques is to obtain better performance and to extend the DFIG-WECS functionality in degraded mode in the event of a failure, and consequently to increase its reliability, unlike the proportional integral (PI) controller which shows less robustness when DFIG non-linearities are considered. The results obtained from these control techniques illustrate well the merits and the effectiveness of each of them in the case of healthy and faulty operations, in particular for the BSC technique, which shows a better performance compared to the SMC technique, which faces the main problem associated with discontinuous control.