Estimation of Magnetization Distribution in Permanent Magnet of Brushless DC Motor

Abstract:

This paper proposes a method to estimate the magnetization distribution in permanent magnet of a Brushless DC motor when the excitation voltage of a magnetizer is changed. First, we show from the experimental results that there is an optimal excitation voltage to reduce the cogging torque of the motor. Next, we show that it is possible to estimate the magnetization distribution in the permanent magnet by using the measured flux density distribution and cogging torque.

• Periodical: Materials Science Forum (Volume 670)
• Pages: 360-368
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.670.360
• Online since: December 2010
• Authors: Takeo Ishikawa, Kouki Yonetake, Nobuyuki Kurita, Masahisa Tsuchiya
• Keywords: Blushless DC Motor, Magnetization State, Permanent Magnet

References

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