• Journal of Electrical Engineering and Technology
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• 제13권3호
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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.

• 전기학회논문지
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• 제65권11호
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• pp.1907-1912
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• 2016

In fact, in order to obtain good performances and low torque ripple, a high-resolution sensor is needed, which is costly and usually needs a special construction for the machine. So researchers are becoming aware of their cost and are exploring the possibility of cost reduction. Information of rotor position is necessary to drive Linear Switched Reluctance Motor(LSRM). Therefore, linear optical encoder is used to detect a mover position. Normally, since the price of encoder, which is used for linear motor is relatively higher than the one used for rotory motor and the cost of additional equipment increases with the length of motor. This is not always appropriate, considering economical efficiency in case of using the linear optical encoder. As a results, LSRM has a great part for the total cost. Therefore, in this paper, we propose LSRM position detecting modeling with reflective type photo-sensor. Additionally, we have investigated the possibility of the reduced position sensor for LSRM drives with advanced control technique. To certify the overall characteristics of the proposed method, a simulation using PSIM software has been carried out and the informative results are displayed.

• Journal of Advanced Marine Engineering and Technology
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• 제39권1호
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• pp.68-74
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• 2015

본 논문은 정격속도 이상의 고속 영역에서 운전되는 스위치드 릴럭턴스 발전기의 효율 개선에 대하여 기술한다. 전류 형상은 발전기 손실에 큰 영향을 미치기 때문에 전류 모양을 조정함으로서 시스템 효율이 개선될 수 있다. 풍력 또는 소수력 발전과 같이 속도 범위가 넓은 경우 정격속도 이상에서도 최적의 전류 형상을 얻을 수 있도록 스위칭각 조정 방법이 제시된다. 제시된 방법을 검증하기 위해 실험장치가 구성되고, 이론의 가능성이 시뮬레이션과 실험결과에 의해 검증된다.

• Journal of Power Electronics
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• 제14권5호
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• pp.866-873
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• 2014

In this paper, a novel 12/8 segmental rotor type switched reluctance motor (SRM) is proposed for cooling fan applications. Unlike conventional structures, the rotor of the proposed structure is constructed from a series of discrete segments, and the stator is constructed from two types of stator poles: exciting and auxiliary poles. Moreover, in this structure, short flux paths are taken and no flux reversion exists in the stator. While the auxiliary poles are not wound by the windings, which only provide the flux return path. When compared with the conventional SRM, the proposed structure increases the electrical utilization of the machine and decreases the core losses, which may lead to a higher efficiency. To verify the proposed structure, the finite element method (FEM) and Matlab-Simulink are employed to get the static and dynamic characteristics of the proposed SRM. Finally, a prototype of the proposed motor was tested for characteristic comparisons.

• Journal of Power Electronics
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• 제15권2호
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• pp.469-478
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• 2015

In order to promote the application of switched reluctance machines (SRM) in electric vehicles (EVs), the braking torque closed-loop control of a SRM is proposed. A hysteresis current regulator with the soft chopping mode is employed to reduce the switching frequency and switching loss. A torque estimator is designed to estimate the braking torque online and to achieve braking torque feedback. A feed-forward plus saturation compensation torque regulator is designed to decrease the dynamic response time and to improve the steady-state accuracy of the braking torque. The turn-on and turn-off angles are optimized by a genetic algorithm (GA) to reduce the braking torque ripple and to improve the braking energy feedback efficiency. Finally, a simulation model and an experimental platform are built. The simulation and experimental results demonstrate the correctness of the proposed control strategy.

• 전기학회논문지
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• 제66권2호
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• pp.315-322
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• 2017

This study presents a novel two­phase eight stator poles and six rotor poles (8/6) switched reluctance machine (SRM) that can compensate for the vibration and noise problems of two­phase 6/3 SRM and compare the characteristics of two SRMs. In the case of two­phase 6/3 SRM, the short flux path and the flux direction inside the stator are not reversed, so they have high efficiency characteristics. However, the use of three rotor poles causes problems of vibration and noise because the radial force applied to the rotor poles is not balance. The proposed two­phase 8/6 SRM has advantages of 6/3 SRM such as the flux­reversal­free stator and it can improve vibration and noise by using six rotor poles due to balanced radial force acting on the rotor poles. In order to make a reasonable comparison between two SRMs, the electromagnetic field structure of 8/6 SRM is designed to have equivalent torque characteristic to 6/3 SRM and then the copper loss and core loss are compared and analyzed. Finally, we compare the effieicney of two SRMs using finite element analysis and compare the distribution of radial force acting on the rotor poles based on Maxwell's stress method.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권7호
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• pp.317-322
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• 2005

Advantages of switched reluctance motor(SRM) include a simple structure, the ability of operation in hash environments and under partial hardware failures, and a wide speed range. However design of SRM for industrial applications is very difficult because motor's inherent none-linearity and sensitivity of design parameter. In this paper, an optimal method for determining design parameters of a switched reluctance motor is researched. The dominant design parameters are stator and rotor pole arc and switching on and off angle. The parameters affecting performance are examined and selected using evolutionary computations and commercial CAD Program. The proposed design process is very fast. reliable and easy to access. The simulated design method proposed is compared with conventional procedure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.80-82
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• 2004

This paper deals with design of linear switched reluctance motors(LSRM) which drive a testing machine of eddy current magnetic repulsion system using Halbach array and conducting plate. The design method employing finite element method and parameter estimation method and a characteristic of LSRM according to variation of parameter is introduced.

• Journal of Electrical Engineering and Technology
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• 제3권1호
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• pp.68-78
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• 2008

This paper introduces a complete package for SRM drive on Power System Computer-Aided Design/Electromagnetic Transients (PSCAD/EMTDC). A three-phase SRM drive is modeled and simulated on PSCAD. The motor is modeled using an accurate nonlinear analytical model that takes into consideration the machine nonlinearities. A current control algorithm is applied for torque ripple minimization to achieve a smooth output torque which is necessary for high performance applications. The motor drive is tested for four-quadrant operations. The modeled SRM is capable of operating as a motor or generator during clockwise and counterclockwise motions. The proposed package helps in understanding the operational principles of switched reluctance motors, investigating the dynamic characteristics of SRM drives, and achieving a high performance dynamic control task.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.877-879
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• 2001

The switched reluctance motor (SRM) has a simple motor construction with no rotor windings. It also has simple concentrated windings on the stator windings. Thus it is expected to be a lower cost machine to manufacture than other motors. This paper has computed an optimal parameters asking for SRM drives using by PC-SRD that was programmed by T. J. E. Miller/M. Mcgilp. According to advanced angle and dwell angle, the output, efficiency, currents and torque were computed. The experiments with 8/6 SRM have tested.