Yun-Ha Song

Ms. Yun-Ha Song

orcid

Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 October 2025 in Actuators
Verified
Journal Article
Open access
PDF file
YSYun-Ha Song
Yun-Ha Song
SSSi-Woo Song
Si-Woo Song
DCDo-Hyeon Choi
Do-Hyeon Choi
SJSu-Bin Jeon
Su-Bin Jeon
WKWon-Ho Kim
Won-Ho Kim
Interior Permanent Magnet Synchronous Motors (IPMSMs) are widely used in the electrification sector; however, reliance on rare-earth magnets imposes constraints stemming from supply instability and mining-related environmental impacts, raising sustainability concerns. To address these issues, this study investigates an IPMSM employing a consequent pole (CP) structure, in which one permanent magnet pole is replaced by iron. Because flux asymmetry in CP IPMSMs can cause torque ripple and associated vibration and noise, we propose an Intersect Consequent Pole (ICP) rotor geometry and evaluate it against a conventional IPMSM under identical stator conditions. The proposed ICP topology reduces permanent magnet usage and provides a rare-earth-reduced design alternative that addresses the vibration/noise trade-off, with a particular focus on electric power steering (EPS) applications. Electromagnetic characteristics and performance were analyzed using finite element analysis (FEA) and verified via FEA-based comparisons.

29 August 2025 in Actuators
Verified
Journal Article
Open access
PDF file
SJSu-Bin Jeon
Su-Bin Jeon
DCDo-Hyeon Choi
Do-Hyeon Choi
HHHyung Sub Han
Hyung Sub Han
YSYun-Ha Song
Yun-Ha Song
WKWon-Ho Kim
Won-Ho Kim
This study proposes a multi-via structure as a loss-reduction design technique to mitigate current crowding in a slotless axial flux permanent magnet motor (AFPM) equipped with printed circuit board (PCB) stators. The PCB stator enables high current density operation through parallel copper-foil stacking and supports an ultra-compact structural configuration. However, current concentration in the via regions can increase copper loss and phase resistance. In this work, the via position and diameter were defined as design variables to perform a sensitivity analysis of current distribution and phase resistance variation. The effects of current density dispersion and the potential for copper loss reduction were evaluated using three-dimensional finite-element analysis (FEA). The results confirm that adopting a multi-via structure improves current path uniformity and reduces electrical losses, thereby enhancing overall efficiency. Furthermore, the analysis shows that excessive via enlargement or overuse does not necessarily yield optimal results and, in certain cases, may lead to localized current peaks. These findings demonstrate that the multi-via structure is an effective and appropriate design strategy for PCB stators and highlight the importance of optimized via placement tailored to each stator configuration.