FCS-MPC-Based Fault-Tolerant Control of Five-Phase IPMSM for MTPA Operation

This article proposes a new fault-tolerant control strategy based on finite-control-set model predictive control (FCS-MPC) for interior permanent-magnet synchronous motor (IPMSM) drives under open-circuit faults, including single-phase and double-phase faults. In particular, the double-phase fault will cause a big disturbance to the performance of the motor, but there is no research focused on it with FCS-MPC. The key of this method is that a z subspace orthogonal to the fundamental space is proposed to reduce the total current harmonic distortions under the single-phase fault. And the distributions of space voltage vectors under a double-phase fault are established to realize the fault-tolerant operation. On the other hand, most of the research is focused on the fault-tolerant control of id= 0, which is not suitable for the IPMSM, due to the ignorance of the reluctance torque. Hence, the proposed strategy is extended into the maximum torque per ampere operation by virtual signal injection, then the amplitudes of phase currents can be reduced and the efficiency of the system can be improved under fault conditions. Compared with the existing fault-tolerant control schemes, the proposed strategy can realize the fault-tolerant operation under open-circuit faults with faster control response and higher operation efficiency, which has been validated by experimental results.