• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.50 no.9
• /
• pp.438-444
• /
• 2001

The simple motor construction and low cost, fault tolerant power electronic drive has made the switched reluctance drive a strong contender for many applications. But the switched reluctance drive does exhibit higher levels of vibration and acoustic noise than that of most competing drives. The main source of vibration in the switched reluctance drive is generated by rapid change of radial force when phase current is extinguished during commutation action. In this paper, a hybrid excitation method is proposed to reduce vibration and acoustic noise of the switched reluctance drive. The hybrid excitation has 2-phase excitation by long dwell angle as well as conventional 1-phase excitation. The vibration and acoustic noise are reduced because the scheme reduces abrupt change of excitation level by distributed and balanced excitation.

• Proceedings of the KIPE Conference
• /
• 2007.07a
• /
• pp.467-469
• /
• 2007

In this paper, design of PMA-RSM(permanent magnet assisted reluctance synchronous motor) for washing machine using FEM(finite element method) is presented and algorithms to maximize electromagnetic torque is introduced. FEM has been approached to show the effects of motor parameters on the developed average torque and maximum torque. The designed motor is a combination of salient poles, which is making reluctance torque, and permanent magnet which are located on the air-gap of rotor to get a enough torque during low speed resign. And to verify availability of the proposed PMA-RSM, various simulation are done as compared with bldc motor which is used for washing machine.

• Proceedings of the KIEE Conference
• /
• 2009.04b
• /
• pp.58-60
• /
• 2009

This paper deals with force characteristic analysis of linear switched reluctance motor using dynamic simulation. First, we calculated flux density of linear switched reluctance motor according to position. Second, analyzed normal force from flux density of linear switched reluctance motor according to position. Also, analysis result compares with data that is derived through a finite element analysis, and proved validity. However, linear switched reluctance motor has non linear characteristic, hence, analysis of propulsion force do not easy using analytical method. Therefore, we presented dynamic characteristic analysis model which is consisted at motor and sensor signal part, etc., and substitute circuit constant that get using magnetic equivalent circuit method, we confirmed propulsion force.

• Proceedings of the KIEE Conference
• /
• 2005.07b
• /
• pp.1291-1293
• /
• 2005

Switched reluctance motors have the advantage a high torque/weight ratio, as the large reluctance torque is made by salient poles of both stator and rotor, and a high reliability. On the other hand, the switched reluctance motors have the disadvantage of a large ripple torque which is made by salient poles. So the application for the industrial fields have been limited to special cases. This paper describes the design of a 12/8 switched reluctance motor using a enemy layer method of the asymmetry rotor. The design is focussed to reduce the torque ripple and radial force in the demanded value. The three dimension finite element analysis method(3D-FEM) was used for decides a enemy layer angle of the asymmetry rotor. This paper presents modifications of the rotor pole shape which reduces the torque ripple.

• Journal of Magnetics
• /
• v.18 no.1
• /
• pp.57-64
• /
• 2013

Flux linkage of phase windings is a key parameter in determining the behavior of a switched reluctance motor (SRM) [1-8]. Therefore, the accurate prediction of flux linkage at aligned and unaligned rotor positions makes a significant contribution to the design of an SRM and its analytical approach is not straightforward due to nonlinear saturation in flux. Although several different approaches using a finite element analysis (FEA) or a curve-fitting tool have been employed to compute phase flux linkage [2-5], they are not suitable for a simple design procedure because the FEA necessitates a large amount of time in both modeling and solving with complexity for every motor design, and the curve-fitting requires the data of flux linkage from either an experimental test or an FEA simulation. In this paper, phase flux linkage at aligned and unaligned rotor positions is estimated by means of a reluctance network, and the proposed approach is analytically verified in terms of accuracy compared to FEA.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.8 no.3
• /
• pp.211-220
• /
• 2003

This paper presents an implementation of direct torque control (DTC) of Reluctance Synchronous Motor (RSM) with an efficiency optimization. The equipment circuit in Reluctance Synchronous Motor which consider with iron losses is theoretically analyzed and the optimal current ration between torque current and exiting current analytically derived to drive RSM at maximum efficiency. For RSM, torque dynamics can be maintained even with controlling the flux level because a torque is directly proportional to the stator current unlike induction motor. The experimental results are presented to validate the applicability of the proposed method. The developed control system show high efficiency features with 1.0 Kw RSM having 2.57 ratio of d/q reluctance.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.54 no.11
• /
• pp.511-518
• /
• 2005

This paper presents the design and drive characteristics of a switched reluctance motor for an electric power pallet vehicle. The designed switched reluctance motor is redesigned by using the finite element analysis(FEA) as a variation of the pole-arc angle for the purpose of an electric power pallet vehicle performance. The output power and torque characteristics of a switched reluctance motor are variable by switching angles of the commutator. Therefor this paper is studied about relationship between the output power and torque characteristics of a switched reluctance motor according to switching angles. The output power of the characteristic point of an electric power pallet vehicle has been shown by experiment. The designed motor drive system operates with the low voltage and high current with using the battery. The core and frame temperatures were described. In this paper, the designed motor is shown better drive characteristics than the DC motor from the rated to maximum, which is verified by the finite element analysis and experimental results.

• Journal of Korean Academy of Nursing
• /
• v.32 no.5
• /
• pp.624-632
• /
• 2002

The number of residents in elderly institution has been increasing due to the change of the family support system. This study was focused on understanding the process of adjustment of the institutionalized elderly using the Grounded Theory approach. Method: There were seven participants, 4 men and 3 women living in 3 different elderly facilities. The data was collected through in-depth interviews and participant observation from June 20, 1999 to January 10, 2000 and analyzed by the Strauss and Corbin's analysis method. Result: 125 concepts were found and grouped into 30 sub-categories and then grouped into 13 categories. These categories are , , , , , , , , , , , and , which were synthesized into the process of adjustment. being the core category. The adjustment process of the facility elderly consisted of : 1. expressive phase of 'reluctance' 2. control phase of 'reluctance' 3. latent phase of 'reluctance' Conclusion: This study offers better understandings on the adjustment process of the institutionalized elderly and provides more appropriate nursing care to the New Comers of these facilities.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.54 no.10
• /
• pp.455-460
• /
• 2005

A simple construction and low cost, fault tolerant power electronic drive has made the switched reluctance drive a strong contender for many applications. But, switched reluctance drive does exhibit higher levels of vibration and acoustic noise than that of most competing drives. The main source of vibration in the switched reluctance drive is generated by rapid change of radial magnetic force when phase current is extinguished during commutation action. In this paper,2 excitation method is proposed and compared to reduce vibration and acoustic noise of the switched reluctance drive. The excitation strategies considered this research are 1-phase, 2-phase and hybrid excitation method. 1-phase method is a conventional and 2-phase method is excited 2 phases simultaneously. The hybrid excitation has 2-phase excitation by long dwell angle as well as conventional 1-phase excitation. The vibration and acoustic noise are compared and tested. Suggested 2-phase and hybrid strategies reduce acoustic noise because the scheme reduces abrupt change of excitation level by distributed and balanced excitation.

• Proceedings of the KIEE Conference
• /
• 1997.07f
• /
• pp.1951-1953
• /
• 1997

A switched reluctance motor (SRM) has very simple structure and robustness. Generally, for driving SRM, several (6-8) switching devices are required. This is weakpoint for reducing the cost of SRM drive. In This paper, we simulate the single phase and three phase SRM, and we compare the performance or single phase SRM with that of three phase SRM through experiment. Finally we suggest the appropriate application of single phase SRM.