• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.443-443
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• 2009

Cogging Torque is induced by the magnetic attraction between the rotor mounted permanent magnet(PM) and the stator teeth. This torque is an unwanted effect causing shaft vibration, noises, metal fatigues and increased stator length. A variety of techniques exist to reduce the cogging torque of PM generator. Even though the cogging torque can be vanished by skewing the stator slots by one slot pitch or rotor magnets, manufacturing cost becomes high due to the complicated structure and increased material costs. This paper introduces a new cogging torque reduction technique for PM generators that adjusts the azimuthal positions of the magnets along the circumference. A 900 kW class PMSG model is simulated using a three dimensional finite element method and the resulting cogging torques is analyzed using the Maxwell tensor stress tensor. Using the 3D simulation, the end contribution of the cogging torque is accurately calculated.

• Journal of Electrical Engineering and Technology
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• v.7 no.5
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• pp.745-752
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• 2012

Transverse flux machine (TFM) has been proved to be very suitable for high-torque, low-speed, and direct-drive situation in industry. But the complex structures and costly permanent magnets (PMs) are two key limitations of its wide range of applications. This paper proposes a new claw pole TFM (ACPTFM) which features an assembled claw pole stator and using the lamination steels material to overcome the complex structures. By combining response surface methodology (RSM) with design of experiment, an optimum design method is put forward to improve the PM's contribution to the torque in order to save the PM's amount. The optimum design results demonstrate the validity of the proposed optimum design method and the optimized model. Eventually, the finite-element analysis (FEA) calculation method, which is used in the optimization process, is verified by the experiments in a prototype.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.12
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• pp.718-724
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• 2004

This study investigates the design factors of Interior Permanent Magnet Synchronous Motor(IPMSM) which is applied to Hybrid electric vehicle as a driving power. Recently, there are many studies of IPMSM for application to Hybrid Electric Vehicle, because IPMSM has characteristics of high torque, high power density and high efficiency which come from reluctance torque due to difference of inductance as well as magnet torque. This study analyzes the inductance and design characteristics of IPMSM by using finite element method and focuses on design and analysis of IPMSM which can operates with high efficiency at low speed range. For this embodiment, magnet shape is changed from conventional block type to arc type without any change of outline dimension of motor and this change of magnet shape makes it possible to increase back EMF and sinusoidal waveform. Analysis results are verified by test of improved and embodied motor. As a test result , increased back EMF and sharply decrease of harmonics are secured and through this contribution of reduced fuel consumption of Hybrid electric vehicle is expected.

• Proceedings of the KIEE Conference
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• 2001.10a
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• pp.104-106
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• 2001

In this paper, it is object of design of high efficiency slotless BLDC motor using film coil. Slotless BLDC motor is able to have high efficiency property and low cogging torque, due to magnetization of stator core have constant contribution by slotless core. But it is difficult to make coil winding of slotless BLDC motor. So we make amateur of slotless BLDC motor using film coil. Film coil is fabricated by drilling, electro-plating and etching of copper/insulator/copper plate. In this paper, after design of slotless BLDC motor for moving axial blower, it is fabricated by NdFeB permanent magnet type rotor and film coil.