• Journal of Electrical Engineering and Technology
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• v.13 no.3
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• pp.1138-1146
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• 2018

Performance comparisons of switched reluctance motor for cooling fan application are dealt in this paper. Conventional and novel segmental type motors with the same dimension are compared. The conventional 12/8 type is very popular and used widely. The structure of segmental rotor type motor is constructed from a series of discrete segments, and the stator is constructed from two types of stator poles: exciting and auxiliary poles. This type of motor has short flux path and no flux reversal in the stator. The auxiliary poles are not wound by the windings and only provide the flux return path. Compared with conventional SRM, the segmental structure increases electrical utilization of the machine and decreases core losses, which leads to higher efficiency. To verify the segmental structure, finite element method (FEM) is employed to get static and dynamic characteristics of both SRMs. Finally, the prototypes of conventional and segmental SRMs are tested for characteristics comparisons.

• Journal of Electrical Engineering and Technology
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• v.4 no.2
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• pp.255-265
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• 2009

This paper presents the acoustic noise and mechanical vibration reduction of a coreless brushless DC motor with an air dynamic bearing used in a digital lightening processor. The coreless brushless DC motor does not have a stator yoke or stator slot to remove the unbalanced force caused by the interaction between the stator yoke and the rotor magnet. An unbalanced force makes slotless brushless DC motors vibrate and mechanically noisy, and the attractive force between the magnet and the stator yoke increases power consumption. Also, when a coreless brushless DC motor is driven by a $120^{\circ}$ conduction type inverter, high frequency acoustic noise occurs because of the peak components of the phase currents caused by small phase inductance and large phase resistance. In this paper, a core-less brushless DC motor with an air dynamic bearing to remove mechanical vibration and to reduce power consumption is applied to a digital lightening processor. A $180^{\circ}$ conduction type inverter drives it to reduce high frequency acoustic noise. The applied methods are simulated and tested using a manufactured prototype motor with an air dynamic bearing. The experimental results show that a coreless brushless DC motor has characteristics of low power consumption, low mechanical vibration, and low high frequency acoustic noise.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.753-755
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• 2002

This paper presents the characteristic analysis by changing the shape and position of auxiliary pole core for Automotive stater motor. The brush contact resistance and mechanical loss calculated from the experimental data are used in characteristic analysis. The Finite Element Analysis Method(FEM) and 3D Equivalent Magnet Circuit Network(EMCN) are used for analysis. The validity of the proposed methods are verified by comparison of analysis results and experimental ones.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.583-585
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• 2001

This paper deals with a simulation and a position control for linear synchronous motor with Halbach array (HA) permanent magnet mover. The results of control simulation for HA-PMLSM having air-core primary are calculated using Matlab Simulink. The prototype of HA-PMLSM is tested DSP (TMS320F240 EVM).

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.70-72
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• 1993

In this paper, we propose the One-Ampere Conductor Method which is able to calculate the flux distribution conventionally and easily, and the improved winding method which suppress space harmonics of magnetomotive force and enhance the utilization of primary iron core in tubular linear induction motor. We examine no-load test to verify propriety of proposed method and analyze characteristics by finite element method. As a result, performances are improved and propriety of primary iron core is enhanced comparing with conventional model.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.138-140
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• 2002

This paper deals with an automatic design procedure for the minimization of iron core loss in a synchronous reluctance motor (SynRM). The focus of this paper is the design relative to hysteresis loss on the basis of rotor shape of a SynRM in the same torque density. The coupled Finite Elements Analysis (FEA) & Preisach model have been used to evaluate the iron core loss with the rotor shape. The proposed procedure allows to define the rotor geometric dimensions starting from an existing motor or a preliminary design. The iron loss has been reduced with a rotor design variation.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.614-616
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• 2000

A ferrite bonded magnet type brushless DC (BLDC) motor which do not have rotor core is analyzed by using finite element method (FEM). The magnetization distribution of the magnet does not have only parallel or radial direction. So, the direction and intensity are taken into account by the analysis of the magnetization procedure. The validity of the analysis method is verified by comparing the analyzed results with measured ones.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.209-213
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• 1998

In the paper, we present the design procedure and analysis the fundamental characteristics for Linear DC Motor(LDM) using permeance method and finite element method (FEM). Designed LDM is made of two permanent magnets, three iron core and armature windings. For the design of the LDM, first of all it is necessary to calculate the air gap flux density and thrust force, after that to determine core size, the numbers of winding turns, winding width, etc. To demonstrate the method of caculation yields the right results, we used Maxwell program package for computing magnetic fields. Finally we find that the proposed design procedure in this paper is effective to design of LDM.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.81-82
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• 2012

A novel kind of switched reluctance motor (SRM) with short flux path is proposed in this paper. Phase excitation in the SRM gives short flux paths, hence reducing the magnetomotive force required to drive the machine, resulting in significant reduction of copper wire and core losses compared to the typical SRM with diametric circulation of magnetic flux. To verify the performance, the characteristics analysis of a double stator SRM, a 6/5 SRM with C-core structure and a 4/5 two-phase SRM which all composed of short flux path and a comparison with conventional SR motors are executed.

• Proceedings of the KIEE Conference
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• 2001.10a
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• pp.78-80
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• 2001

This paper deals with a comparison between the secondary Halbach array and conventional array of permanent magnets(PMs) in air-core type linear synchronous motor(LSM). Two types of PMLSM are analyzed and compared, with reference to the following parameters as variables: magnetic field, thrust and back emf.