Fault-tolerant Variable Structure Control Of a Low Speed 6-Phase Induction Generator

In this paper, we will introduce the variable structure control (VSC) of a symmetrical six-phase induction generator. We will use this VSC in order to control the inner current loops of a squirrel cage six-phase induction generator (SC6PIG). Our control algorithm switches between positive and negative feedback according to the position of the operating point in the phase plane. This technique guarantees the robustness of the (SC6PIG) in case of loss of one to three stator phases or machine converter legs. The switching line slope and the initial operating point have been set so that the system starts with a negative feedback, then it continuously switches back and forth to positive feedback in order to maintain the desired trajectory of the system. The simulation and experimentation results will demonstrate the effectiveness and robustness of this technique for current control of (SC6PIG) in healthy or faulty modes with one phase loss.