Analysis of aviation fault-tolerant generation system with flux weakening control

The paper presents an aviation fault-tolerant generation system which is based on the Fault-tolerant Permanent Magnet Motor. Constant power output, wide range of speed, high power density and high reliability are required in this system. A new method for flux weakening control is proposed, which is used to elaborate analytical expressions for the demagnetizing current in d-axis of the permanent magnet. The three-phase four-leg topology is utilized to restructure the circuit by replacing the faulty phase with the fourth leg when a fault occurs. The fault diagnostic strategy can be achieved by combining the characteristics of the fault tolerant Permanent Magnet Motor (magnetic isolation and large inductance) and the space-voltage pulse width modulation (SVPWM) control. Simulations and experiments over the system prove that the proposed method for flux weakening control leads to the easier access to the d-axis current, and the proposed fault tolerant control strategy is proved to be effective.