A SVPWM-based fault-tolerance control method for three-level inverter under different working conditions

Aiming at the open-circuit fault of three-level NPC inverter used in traction system, the difference of current path at inverter legs before and after the fault is analyzed, and the change of space voltage vectors distribution is discussed. Then, based on the principle of Space Vector Pulse Width Modulation(SVPWM) and through the reconstruction of the basic voltage vectors, two fault-tolerant methods for different operating conditions of the train are proposed, and the idea of weak magnetism is innovatively proposed to realize fault-tolerant control at the condition on high speed. Simulation results show the effectiveness of the proposed methods.