Hari Prasetijo, Moh. Khairudin, Ketut Wirtayasa, Muhammad Syaiful Aliim, Widhiatmoko Herry Purnomo
Cogging torque remains a critical barrier to achieving torque smoothness, energy efficiency, and structural reliability in radial-flux permanent magnet synchronous machines (RF-PMSMs), particularly in low-speed and variable-speed renewable energy systems. This study presents a systematic literature review (SLR) of 64 peer-reviewed journal articles, categorizing cogging torque mitigation strategies into five key domains: stator geometry, rotor geometry, magnet geometry, winding layout, and non-geometric techniques. To complement the synthesis, bibliometric mapping was performed using VOSviewer, and a Thematic Map was generated via Biblioshiny (Bibliometrix R) from article metadata. This integrated approach not only identifies widely adopted techniques but also uncovers underexplored yet high-potential research fronts. In particular, niche and emerging themes are highlighted as promising directions for innovation. The review also underscores the importance of multi-objective design optimization, advanced material strategies, and real-world validation under manufacturing and operational constraints. Overall, the study provides a structured and forward-looking contribution to advancing RF-PMSM design, with specific novelty in cogging torque reduction for high-performance and sustainable energy applications. © 2018-2026, Rangsit University.
Department of Electrical Engineering, Universitas Jenderal Soedirman, Purwokerto, 53112, Indonesia; Doctoral Program in Ilmu Teknik, Universitas Negeri Yogyakarta, Yogyakarta, 55218, Indonesia; Department of Electrical Engineering, Universitas Negeri Yogyakarta, Yogyakarta, 55218, Indonesia; Research Center for Energy Conversion and Conservation, National Research and Innovation Agency, Bandung, 10340, Indonesia
