IET Electric Power Applications

Rahmani‐Fard, Javad; Mohammed, Mohammed Jamal

2025 IET Electric Power Applications

doi: 10.1049/elp2.12537

This paper proposes a multi‐level optimisation design strategy aimed at enhancing the fault‐tolerant capability of a Yoke‐less Axial‐Field Flux‐Switching Permanent Magnet (YASA‐AFFSPM) motor. The research addresses the crucial requirement for robustness and reliability in electric motor systems utilised in safety‐critical applications. By employing a comprehensive multi‐objective optimisation approach, the motor's design is refined at three levels based on the main effect stratification of design variables for the YASA‐AFFSPM motor. The design variables are divided into three levels and optimised, resulting in the attainment of a comprehensive optimal solution that considers multiple design goals, including average torque, cogging torque, and fault‐tolerant capability. The optimal design places a primary emphasis on attaining a substantial level of fault tolerance for both open‐ and short‐circuit faults. This is accomplished by reducing the ratio of mutual‐inductance to self‐inductance. To streamline optimisation, the Kriging model approximates finite element analysis at each level. Furthermore, the effectiveness of the design is showcased through the utilisation of a dual‐channel winding configuration. A prototype is constructed, and experimental validation demonstrates a significant improvement in fault‐tolerance performance, with results indicating enhancements of 14% in average torque and 41% in cogging torque.

Zhu, Haotian; Zhang, Li; Peng, Zhongfei; Tan, Feixue; Xu, Lei

2025 IET Electric Power Applications

doi: 10.1049/elp2.12538

This paper proposes a new low‐noise sensorless control strategy for the permanent magnet synchronous motor (PMSM) drives to tackle audible noise caused by high‐frequency injection method. The traditional noise reduction methods face limitation in improving estimated accuracy of rotor position due to the signal delay with fixed frequency signal. To overcome this issue, a low‐noise sensorless control strategy is developed, which consists of two parts. First, with the injection of the proposed variable‐frequency voltage signal, significant noise reduction can be achieved due to its characteristics of multi‐frequency switching and multi‐modal amplitude tuning. Secondly, a delayed effects‐aware demodulated signal is designed to reduce the impact of system delay, which can further improve the estimation accuracy of rotor position. As a result, the proposed low‐noise sensorless control scheme can suppress audible noise and further improve position estimation accuracy. Also, the steady‐state and dynamic performances of the motor drive system can be enhanced. Finally, comparative experiments under steady‐state and dynamic conditions demonstrate the superiority of the proposed method in PMSM.