Abstract
This research proposes a robust optimal design methodology to reduce the cogging torque of a hard disk drive (HDD) spindle motor due to the coil-positioning error of the magnetizer. The design optimization problem of the magnetizer is formulated with an objective function of the cogging torque and the constraints of the torque constant. The coil-positioning errors measured by computerized tomography are considered as the random variables of the robust optimal design problem. Additional design variables of the magnetizer are chosen in the optimization problem, such as back-yoke thickness, notch depth, etc. Magnetic finite element analysis of the HDD spindle motor is also performed to calculate the cogging torque and torque constant. The cogging torque and torque constant of the optimal design are compared with those of the conventional design, demonstrating that the proposed method effectively reduces the cogging toque of the HDD spindle motor.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Akihiro D, Shinichi Y (1992) Cogging torque investigation of PM motors resulting from asymmetry property of magnetic poles: influence of performance variation between permanent magnets. Electr Eng Jpn 163:95–102
Hong KJ, Choi DH, Kim MS (2000) Progressive quadratic approximation method for effective constructing the second-order response surface models in the large scaled system design. Trans Korean Soc Mech Eng A 24:3040–3052
Jewell GW, Howe D (1992) Computer-aided design of magnetizing fixtures for the post-assembly magnetization of rare-earth permanent magnet brushless DC motors. IEEE Trans Magn 28:3036–3038
Koh CS (2003) New cogging-torque reduction method for brushless permanent-magnet motors. IEEE Trans Magn 39:3503–3506
Lee CJ, Jang GH (2011) Development of a new magnetizing fixture for the permanent magnet brushless DC motors to reduce the cogging torque. IEEE Trans Magn 47:2410–2413
Lee CJ, Lee CI, Jang GH (2011) Source and reduction of uneven magnetization of the permanent magnet of a HDD spindle motor. IEEE Trans Magn 47:1929–1932
Lin YK, Hu YN, Lin TK, Lin HN, Chang YH, Chen CY, Wang SJ, Ying TF (2000) A method to reduce the cogging torque of spindle motors. J Magn Magn Mater 209:180–182
Nakata T, Takahashi N (1986) Numerical analysis of transient magnetic field in a capacitor-discharge impulse magnetizer. IEEE Trans Magn MAG-22: 526–528
PIDOTECH Inc. PIAnO user’s manual version 3.3
Wang GG, Shan S (2007) Review of metamodeling techniques in support of engineering design optimization. ASME J Mech Des 129:370–380
Acknowledgments
This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MEST) (No. 2012R1A2A1A01).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Lee, C., Jang, G. Robust optimal design of a magnetizer to reduce the harmonic components of cogging torque in a HDD spindle motor. Microsyst Technol 20, 1497–1504 (2014). https://doi.org/10.1007/s00542-014-2153-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00542-014-2153-4