• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.857-860
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• 2006

It is important to diminish noise source of an electric motor used in appliances. We studied on the noise reduction of BLDC motor to drive a fan. Especially, this study was focused on detent torque caused by interaction between a permanent magnet of rotor and groove in stator. This source and rotating system brought about a resonance. This paper showed that the higher harmonic component of this torque had a main factor to lessen noise. So, we had designed new magnets with shape like a peanut and pseudo-sinusoidal flux density for low-noise BLDC motor in refrigerator.

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.171-173
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• 1997

This paper presents analysis of the radial force density in brushless DC motor of which distribution is not uniform in the axial direction. The analysis considering 3D shape of teeth and overhang is not only important but essential to calculate the radial force density that acts on the teeth of stator, because it is frequent source of vibration and changes at the end of teeth. For the analysis, a new 3D equivalent magnetic circuit network method taking into account movement of the rotor without remesh is proposed. The radial force density is calculated by Maxwell stress tensor and analyzed by discrete Fourier transform.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2001.04a
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• pp.59-62
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• 2001

An axial-type turbine design technology is developed. In order to design one-stage turbine, preliminary design method is applied, and then design parameters are chosen after analyzing the gas properties within the turbine passage using the streamline curvature method. Stator blade is designed using C4 Profile, and rotor blade is designed using shape parameters. The output power is measured with various RPM and input power. The experimental result shows that the output power is proportionally decreased with the negative incidence angle.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.8
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• pp.27-31
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• 2010

Torque ripple of the motor used in EPS raises vibration problem on steering system. To solve this problem, this paper proposes a optimum design for torque ripple reduction of Surface-mounted Permanent Magnet Synchronous Motor(SPMSM) in EPS. Through analyis back-EMF using Finite element method as changing the shape of permanent magnet and stator shoe, we presented the method of torque ripple redution.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.118-120
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• 1999

This paper describes a new procedure to develop a systems model of a universal motor based on finite element analysis. The purpose of this paper optimized fabrication of Universal Motor for improving its efficiency and performance and driving range. To do this, various design parameters are set such as a number of teeth and stator shape, etc. As results, the optimized model has made good improvement compared with those of the initial.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.247-249
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• 1998

This paper has proposed an optimized universal motor for improving its performance and cost using FEM program. To do this, various design parameters are set such as air gap length, shape of stator and pole shoe, rotor slot, rotor shaft diameter, etc. As results, the optimized model has made good improvement compared with those of the initial.

• Journal of Magnetics
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• v.16 no.3
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• pp.288-293
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• 2011

Generally, the discontinuous armature permanent magnet linear synchronous motor (PM-LSM) is composed by the stator block (accelerator, re-accelerator, and decelerator) and the free running section. However, the stationary discontinuous armature design involves the velocity variation of the mover during drive when the armature's non-installation part changes over to installation part as a result of the outlet edge of the armature. Therefore, we considered deforming the shape of the outlet edge at the armature and apply skew on the permanent magnet by displacing the two magnet segments of each pole. This paper presents the results of a three-dimensional (3-D) numerical analysis with a finite element method (FEM) of the force exerted by the outlet edge.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.491-498
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• 2004

Lift Fan Engines of JAXA's conceptual Jet VTOL aircraft have a very small bellmouse shape air intake, which make some differences in aerodynamic design of the blades. To obtain a better rotor or stator blade design, this paper performs a numerical analysis of the throughflow on a lift fan as a two-dimensional axisymmetrical flow. Based on the last report focusing on the air intake's influence on the throughflow, a more realistic bellmouse air intake case is treated to reconsider the influence on the throughflow by the small bellmouse air intake. Three work input patterns are tested to reduce some problematic influences on the throughflow or blade designs. The obtained result shows one of acceptable blade designs for the lift fan engine.

• Proceedings of the KIEE Conference
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• summer
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• pp.1052-1054
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• 2004

This paper deals with a Double type Transverse Flux Linear Motor(TFLM) which can be applied to high power system. This type can reduce overall system volume because of the configuration which has double flux path of prototype per phase, and less number of phase and turns. This TFLM is based on permanent magnet excitation, and the pole shape is designed to reduce attraction force between stator and mover poles. In the paper, the basic configuration of double type and the principle of movement are introduced. After performing the characteristic analysis by 3-dimensional equivalent magnetic circuit network, the results are discussed.

• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1544-1550
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• 2014

In this paper, an adaptive optimization strategy utilizing Kriging model and genetic algorithm is proposed for the optimal design of electromagnetic devices. The ordinary Kriging assisted by the spherical covariance model is used to construct surrogate models. In order to improve the computational efficiency, the adaptive uniform sampling strategy is applied to generate sampling points in design space. Through several iterations and gradual refinement process, the global optimal point can be found by genetic algorithm. The proposed algorithm is validated by application to the optimal design of a switched reluctance motor, where the stator pole face and shape of pole shoe attached to the lateral face of the rotor pole are optimized to reduce the torque ripple.