This article proposes a modified flux observer for sensorless direct torque control (DTC) of the dual three-phase permanent-magnet synchronous motor. The proposed method can improve torque performance without a position sensor. The flux observer is proposed to obtain the stator fluxes and rotor fluxes. The stator fluxes can be utilized to calculate the amplitude of torque and flux for DTC system. Meanwhile, the position information can be detected from the rotor fluxes by using a normalized phase-locked loop. This new flux observer can overcome the disadvantages due to the dc bias, initial value, and harmonic components. The stability of the proposed observer is also analyzed in this article. In addition, a fault-tolerant DTC scheme for open-circuit fault is introduced. The performances of torque control and position estimation are evaluated under healthy, open-circuit fault, and fault-tolerant conditions. Simulation and experimental evaluation are carried out to confirm the effectiveness of the proposed sensorless DTC scheme.

中文翻译：

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考虑开路故障的双三相永磁同步电机无传感器直接转矩控制的改进磁通观测器

本文提出了一种改进的磁通观测器，用于双三相永磁同步电机的无传感器直接转矩控制 (DTC)。所提出的方法可以在没有位置传感器的情况下提高扭矩性能。建议使用磁通观测器来获得定子磁通和转子磁通。定子磁通可用于计算 DTC 系统的转矩和磁通幅值。同时，可以通过使用归一化锁相环从转子磁通中检测位置信息。这种新的磁通观测器可以克服由于直流偏置、初始值和谐波分量造成的缺点。本文还分析了所提出的观测器的稳定性。此外，还介绍了一种针对开路故障的容错DTC方案。在健康、开路故障和容错条件下评估转矩控制和位置估计的性能。进行了仿真和实验评估，以确认所提出的无传感器 DTC 方案的有效性。