• Journal of Magnetics
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• 제18권3호
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• pp.352-356
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• 2013

Recently, the stationary discontinuous armature, Permanent Magnet Linear Synchronous Motor (PM-LSM), was suggested as a driving source for long-distance transportation system. However, as these motors arrange armatures discontinuously, an edge occurs thereby leading to a cogging force. This works as a factor that hinders the acceleration and deceleration that takes place when movers enter into and eject from armatures. Therefore, in this study, the installation of auxiliary teeth on the edge of the armature of PM-LSM is suggested in order to reduce the cogging force caused by the edge when the armature is placed in a discontinuous arrangement. Auxiliary teeth are optimally designed by a 2-D numerical analysis using the finite element method was performed to generate the optimum design of the auxiliary teeth. The validity of the study was confirmed through the comparison of the cogging force induced at the edge in respect to the design parameter using the basic model.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.926-927
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• 2008

This paper presents the ZVZCS(Zero- Voltage and Zero-Current-Switching) Full-Bridge converter using the secondary coupled inductor and auxiliary capacitor. The converter with phase-shift control is proposed to reduce the circulating loss in primary and the voltage stress in secondary side. Using a coupled winding of the output inductor, two auxiliary capacitors are generated to reset the primary current at circulating interval.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 춘계학술대회 논문집 에너지변화시스템부문
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• pp.161-164
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• 2009

This paper presents the ZVZCS(Zero Voltage and Zero-Current-Switching) Three-Level converter using the secondary coupled inductor and auxiliary capacitor. The converter with phase-shift control is proposed to reduce the circulating loss in primary and the voltage stress in secondary side. Using a coupled winding of the output inductor, two auxiliary capacitors are generated to reset the primary current at circulating interval.

• 전력전자학회논문지
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• 제4권5호
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• pp.449-454
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• 1999

본 논문에서는 자동차 헤드라이트용 고압방전등 안정기의 새로운 전력변환 구조를 제안한다. 제안된 전력변환 구조는 기존의 안정기와 같이 고압방전등의 전력제어를 하는 고주파 DC-DC 컨버터와 저주파 DC-AC 인버터로 구성되어 있지만, 컨버터에 보조권선을 사용하여 고압방전등의 점등개시용 절연파괴전압을 얻기 위한 고압변압기의 1차측 전압을 DC-DC 컨버터의 직류단과 분리하여 공급하게 되어 있다. 따라서 기존의 시스템에 비해 작은 전압 정격을 가지는 소자를 사용할 수 있어 시스템의 효율 향상 및 가격 절감을 할 수 있다.

• 조명전기설비학회논문지
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• 제14권1호
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• pp.82-88
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• 2000

본 논문은 궤환 권션을 갖는 $S^4-PFC$ 컨버터에서 기존의 DC 버스 전압 제한 능력과 높은 효율을 유지하면서 입력 전류 파형을 개선시킬 수 있는 저비용의 보조회로펀 제안하였다. 제안한 컨버터를 검증하지 위하여 궤환 권선을 갖는 컨버터를 분석하였다. 제안한 컨버터의 성능응 입증하기 위해 상용 라인 입력 전압범위에서 5[V], 65[W] 출력과 스위칭 주파수 100[kHz]에서 동작하는 컨버터 설계하였다. 그리고 실험을 통하여 기존 컨버터에 비하여 라인 전류 파형의 첨두값이 50[%] 감소하고 라인 주기에서 전력이용률이 증가하였다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제50권5호
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• pp.238-245
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• 2001

During an AC motor's start-up accelerating period, a large amount of current is required to reach to the rating speed. This is called in-rush current. This peak in-rush current can be more than about several times the operating or steady-state current in the full load rating of the motor. In-rush current is present in both and electronic ballasts. The main area of concern is the tripping of circuit breaker and fuses which can affect electrical system components From this, we can see that the electrical power controllers will be rather concerned, since they have to supply the actual current necessary to start the motor. This paper presents a new method to reducing in-rush current and energy saving of the single-phase induction motor used in air-conditioner. It can be obtained that proposed system is low cost and small size as compared with other controller. Experiments are focused on a capacitor starting single-phase induction motor. The optimal power saving and in-rush current limiting by phase angle control are verified by experimental results. Also, auxiliary winding was controlled by electronic starting switch.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.224-227
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• 2003

Single phase induction motor(SPIM) is one of the most widely used type of low power AC motors in the world, especially for domestic or commercial applications where a three phase power supply is not available. Fractional horse power of the SPIM have no starting torque their own. So there are several ways of starting SPIMS. The most common type is the starting capacitor installed in series with the auxiliary winding to increase the starting torque. Also, the auxiliary winding is disconnected once the speed of the motor reaches 70 to 80 [%] of the rated speed. In the conventional systems, this function is conducted by a centrifugal switch. But the mechanical centrifugal switch has many problems such as switch malfunction. This paper presents the starter design of SPIM capacitor starting switch using microcontroller.

• 전력전자학회논문지
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• 제21권1호
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• pp.1-9
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• 2016

In this study, two types of switched reluctance motors (SRMs) with segmental rotors are presented in detail. The first is a 6/5 segmental rotor type, whereas the second is a 12/8 segmental rotor type. Both motor types have the same stator, rotor, and winding configurations. The stator is constructed with special stator poles, namely, exclusively designed exciting and auxiliary poles. The rotor is constructed from a series of discrete segments, each of which is embedded into the nonmagnetic isolator. The windings are only wound on the exciting poles, and no winding is wound on the auxiliary poles. Given these configurations, short flux paths and high flux-linkage utilization rate are achieved in the proposed motors, which may reduce the magnetomotive force requirement and increase the electrical utilization of a machine. To verify the effectiveness of the proposed motors, their characteristics, such as magnetic flux distribution, flux-linkage, torque, radial force, and efficiency, are analyzed and compared with those of a conventional 12/8 SRM. Meanwhile, two prototypes, one for each proposed segmental rotor type, are also designed and manufactured. Finally, the validity of the proposed motors is further verified by test results.

• 한국전자통신학회논문지
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• 제7권5호
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• pp.1067-1072
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• 2012

현재 선형 전동기는 많은 연구가 진행되어 그 응용분야가 산업전반에 확대되고 있다. 이중 반송장치 분야에서 영구자석 선형 동기 전동기(Permanent Magnet Linear Synchronous Motor:이하 PMLSM)가 각광을 받고 있다. 영구자석 선형 동기 전동기는 구조적으로 간단하며 고속화 고추력화 등의 장점을 가지고 있지만 전기자를 반송경로 전장에 배치하는 지상 1차측 시스템을 장거리 반송장치에 적용하면 재료비용의 증가 및 제작시간 증가 등의 문제점이 발생한다. 따라서 전기자를 분산(불연속) 배치하는 방식이 제안되고 있다. 하지만 이러한 전기자 분산배치 방식은 구조적으로 단부가 존재하고 이러한 단부에 의해 코깅력이 발생한다. 이는 추력 맥동의 원인이 되며, 소음과 진동을 발생시킨다. 따라서, 본 연구에서는 전기자를 분산배치 할 경우 필연적으로 생기는 단부에 의한 코깅력을 저감하기 위해 Bifurcating을 적용한 집중권 PMLSM에 보조극 설치법을 제안한다. 또한 그에 따른 단부 코깅력 특성을 2차원 유한요소법(FEA)을 이용하여 분석하였다.

• 전기학회논문지P
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• 제60권4호
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• pp.220-226
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• 2011

This paper proposes a straightforward method of analyzing the operation characteristics for the capacitor run single-phase induction motor from the traditional equivalent circuit based on the revolving field theory. The proposed method consists of five procedures as follows: mechanical loss segregation, iron loss segregation and calculation of the equivalent circuit parameters, recalculation of parameters of the main winding side, calculation of the auxiliary winding magnetizing reactance and effective turn ratio, and analyzing the operation characteristics for this motor. When the characteristics are analyzed, the segregated mechanical and iron losses are considered as a loss resistance across input terminals of the equivalent circuit for the analysis. The validity of the proposed method is verified from the comparison between the computed results and the experimental ones for the operation characteristics.