A nonlinear control method for three-phase three-level NPC rectifier

A nonlinear control strategy is proposed for the three-phase three-level NPC rectifier based on the feedback linearization theory. The proposed strategy can realize the decoupled control of active and reactive current of the VSR in the d-q frame. A strategy of changing the voltage adjusting coefficient to adjust the dwelling time of the positive and the negative small vectors to control the neutral point potential balance is proposed based on the simplified SVM. The control strategy is simulated and simulation results prove the validity of the proposed modeling and control strategy.