Open-Circuit Fault-Tolerant Control for APMSM Based on Coil-Sequential Activation Strategy

In the annular permanent magnet synchronous motor (APMSM) control system, the coil sequential activation strategy enables a single stator to drive multiple movers simultaneously. However, it also increases the risk of open-circuit faults. This article proposes a fault-tolerant control (FTC) algorithm that addresses one coil open-circuit fault and two coil open-circuit faults within this driving strategy. The algorithm ensures that the system maintains constant electromagnetic thrust even in the presence of coil faults. To assess its effectiveness, both theoretical analysis and experimental validation are conducted. The results demonstrate that the proposed FTC algorithm successfully reconfigures the currents in healthy coils during an open-circuit fault, thereby preserving system stability and performance. This is verified through current closed-loop tests, as well as under no-load and load conditions, where the system exhibits performance nearly identical to normal operation despite coil faults.