The Modified Sliding Mode Control of a Doubly Fed Induction Generator for Wind Energy Conversion During a Voltage Dip

In this paper we present nonlinear control of the DFIG used in a wind energy conversion system (WECS). The DFIG is directly connected to the grid, moreover the the rotor is connected to the back-to-back converters. the DFIG's active and reactive powers are regulated by controlling the converters. In this work we used 2 methods based on sliding mode to control the rotor side converter. The first one is a normal sliding mode control using with reliable grid, the second one is a modified sliding mode used during the voltage dip. The machine is tested in association with a wind turbine. Simulations results are presented and discussed for the whole system.