Robust coordinated fault-tolerant control for aerospace multi-motor synchronous drive systems against inverter fault

Synchronous motion is an essential function for multi-motor drive systems, which have been applied in high-precision space collaborative manipulators, satellite systems, and other aerospace industrial fields. To maintain the desired high precision of synchronization in the case of motor inverter fault, a coordinated fault-tolerant control (FTC) scheme is proposed in this paper for the drive system consisting of multiple brushless direct current motors with an adjacent cross-coupling structure. Firstly, the proposed scheme develops a robust coordinated FTC control law based on synergetic control theory, in which the expected manifold of the fault-tolerant synergetic controller is devised to guarantee the synchronization preferentially in the fault case. To enhance system robustness, the control framework incorporates a disturbance observer and an adaptive technique to effectively mitigate the impact of load disturbances. Secondly, the asymptotic stability of the FTC system is proven via Lyapunov theory. Finally, simulation and test experiments on the speed synchronous control of a triple-motor system verified the effectiveness of the developed FTC strategy.