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2026-05-04 Latest Published

A Deadbeat Fault-Tolerant Control Strategy for PMSM Demagnetization Faults Based on an Improved Flux Linkage Observer
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By Yang Zhang Wancheng Xie Yang Gao Jiahao Zhang Moutao Li

Progress In Electromagnetics Research C, Vol. 170, 15-27, 2026

doi:10.2528/PIERC26030706 | Google Scholar

Abstract

To address issues such as reduced motor output performance and diminished load capacity caused by permanent magnet demagnetization in Permanent Magnet Synchronous Motor (PMSM), a super-twisting algorithm-based fault-tolerant predictive control strategy for demagnetization faults in PMSM is proposed. First, the improved super-twisting non-singular fast terminal sliding mode observer (IST-NFTSMO) is constructed to accurately observe the flux linkage and predict the current at the next moment. Based on the observed values, a deadbeat fault-tolerant predictive control (DFTPC) algorithm is built to compensate for the torque loss due to permanent magnet demagnetization, thereby achieving fault-tolerant control of the system. Second, a sliding mode controller based on a novel reaching law is designed, thereby overcoming the shortcomings of traditional control strategies in PMSM vector control systems, such as poor anti-interference capability and slow response speed. Finally, experimental results demonstrate that after a demagnetization fault occurs in the PMSM, the proposed method effectively improves the fault tolerance capability of the PMSM system while ensuring the dynamic response speed of the control system, thereby endowing the system with enhanced stability and robustness.

2026-05-04

PIER C

Vol. 170, 15-27, 2026

doi:10.2528/PIERC26030706

download: 1

A Deadbeat Fault-Tolerant Control Strategy for PMSM Demagnetization Faults Based on an Improved Flux Linkage Observer

Yang Zhang, Wancheng Xie, Yang Gao, Jiahao Zhang and Moutao Li

2026-05-03

PIER C

Vol. 170, 1-14, 2026

doi:10.2528/PIERC25120601

download: 36

Design Optimization of a Permanent Magnet Biased Fault Current Limiter via Pattern Search for High Efficiency and Reduced Material Use

Tirtha Sankar Daphadar, Tapan Santra and Amalendu Bikash Choudhury

This paper presents a useful design optimization methodology for a permanent-magnet-biased fault current limiter (PMFCL), aiming to achieve good fault current limiting performance with small magnetic materials and their losses. A physics-based magnetic circuit modelling approach is developed to update the nonlinear core saturation and permanent magnet biasing, enabling fast and reliable analysis of candidate designs. Additionally, a weighted multi-objective formulation is adopted to balance fault current mitigation, material volume, and loss minimization. The resulting optimization problem is solved by means of a deterministic pattern search approach, which enables efficient design space exploration without access to gradient information. The optimized configurations are validated using the finite-element simulations, and the robustness of the configurations under practical operating conditions is analyzed. The obtained results show a significant reduction of the magnetic material volume with the optimized PMFCL without compromising and, in certain cases, with an improvement of the function of fault current limiting against a baseline design. The research identifies technical configurations of design that are practical for real-world deployment. The combination of reduced material usage, passive operation, and better energy efficiency means the proposed PMFCL represents a reliable and sustainable solution for better protection of modern power systems, especially in areas where power systems are cost-sensitive and infrastructure-limited.