• 전기학회논문지
• /
• 제66권11호
• /
• pp.1663-1668
• /
• 2017

A BLDC motor with higher number of phases has several advantages, compared to the conventional three-phase BLDC motors. It can reduce the commutation torque ripple and the iron loss without increasing the voltage per phase and increase the reliability and power density. Higher number of phases increase the torque-per-ampere ratio for the same machine volume and output power by widening the electrical conduction period. In this paper, the proposed seven-phase BLDC motor drive system is made into several functional modular blocks, so that it can be easily extended to other ac motor applications: back-EMF block, hysteresis current control block, pwm inverter block, phase current block, and speed/torque control block. Also in a system of BLDC motor drive, the PI controller has been widely used in the speed controller because of the simple implementation. To obtain a good speed response in a general drive system using the PI controller, the high bandwidth of a controller is established. therefore, in this paper, a Fuzzy controller is applied to the 7-phase BLDC motor drive system in order to improve the speed control performance. The Fuzzy controller is compared with a conventional PI controller through the experiment with respect to speed dynamic responses. These experimental results show that the Fuzzy controller of the 7-phase BLDC motor drive system is superior over the conventional PI controller. The algorithm using the Fuzzy controller can improve a comfortable ride in the field of high performance 7-phase BLDC motor drive applications.

• 전기전자학회논문지
• /
• 제24권1호
• /
• pp.170-177
• /
• 2020

본 논문은 HF/LF 변조 방법을 적용한 ANPC (active neutral point clamped) 인버터의 스위치 개방 고장에 대응하기 위한 허용 제어 방법을 제안한다. 기존 Si 기반 인버터에 비해 SiC MOSFET과 Si IGBT로 구성된 ANPC 인버터는 시스템의 효율이 높고 출력 품질이 우수하다. HF/LF 변조는 커뮤테이션 루프를 줄일 수 있어 MW 급 대용량 인버터를 위해 사용되는 변조 기법이다. MW 급 인버터의 스위치 개방 고장은 부하에 심각한 손상을 입히며, 인버터가 동작을 멈출 경우 막대한 경제적 손실을 야기한다. 제안하는 스위치 개방 고장의 허용 제어 기술은 ANPC 인버터의 지속적인 운전을 가능하게 하며 신뢰성을 향상 시킨다. 제안하는 기법의 성능은 시뮬레이션 결과를 통해 검증한다.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2018년도 추계학술대회
• /
• pp.434-436
• /
• 2018

유치원이나 어린이집 통학 차량의 탑승 사고는 여러 가지 정책적 조치에도 불구하고 꾸준히 발생하고 있다. 이를 최소화하기 위해서는 운전자가 간편하게 조작할 수 있는 차량 탑재형 안전 통학 관리 소프트웨어와 아동의 안전 통학 여부를 관리하고 부모에게 적시에 알려주는 모바일 앱의 병행 사용이 필요하다. 본 논문은 이 중 안전 통학 관리 모바일 앱의 설계와 구현에 대하여 설명한다. 이 안드로이드용 앱은 학부모 모드에서는 정류장마다 GPS를 이용한 버스의 현재 운행 상황 및 아동의 개인 탑승 여부를 알려주고 동승 교사는 RFID 미소지자나 미인가 동승자(부모, 조부모 등)의 처리 등 예외 상황 관리도 가능하다.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2005년도 전력전자학술대회 논문집
• /
• pp.774-777
• /
• 2005

In this paper, a constant frequency phase shifting PWM controlled voltage source full bridge-type series load resonant high-frequency inverter using the IGBT power modules is presented for innovative consumer electromagnetic induction heating applications such as a hot water producer, steamer and super heated steamer. The full bridge arm side link passive quasi-resonant capacitor snubbers in parallel with the each power semiconductor device and high frequency AC load side linked active edge inductive snubber-assisted series load resonant tank soft switching inverter with a constant frequency phase shifted PWM control scheme is discussed and evaluated on the basis of the simulation and experimental results. It is proved from a practical point of view that the series load resonant and edge resonant hybrid high-frequency soft switching PWM inverter topology, what is called class DE type. including the variable-power variable-frequency(VPVF) regulation function can expand zero voltage soft switching commutation range even under low output power setting ranges, which is more suitable and acceptable for induction heated dual packs fluid heater developed newly for consumer power utilizations. Furthermore, even in the lower output power regulation mode of this high-frequency load resonant tank high frequency inverter circuit it is verified that this inverter can achieve ZVS with the aid of the single auxiliary inductor snubber.

• Journal of Electrical Engineering and Technology
• /
• 제2권1호
• /
• pp.89-97
• /
• 2007

This paper presents a new circuit topology of active edge resonant snubbers assisted half-bridge soft switching PWM inverter type DC-DC high power converter for DC bus feeding power plants. The proposed DC-DC power converter is composed of a typical voltage source-fed half-bridge high frequency PWM inverter with a high frequency planar transformer link in addition to input DC busline side power semiconductor switching devices for PWM control scheme and parallel capacitive lossless snubbers. The operating principle of the new DC-DC converter treated here is described by using switching mode equivalent circuits, together with its unique features. All the active power switches in the half-bridge arms and input DC buslines can achieve ZCS turn-on and ZVS turn-off commutation transitions. The total turn-off switching losses of the power switches can be significantly reduced. As a result, a high switching frequency IGBTs can be actually selected in the frequency range of 60 kHz under the principle of soft switching. The performance evaluations of the experimental setup are illustrated practically. The effectiveness of this new converter topology is proved for such low voltage and large current DC-DC power supplies as DC bus feeding from a practical point of view.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2005년도 춘계종합학술대회
• /
• pp.959-962
• /
• 2005

서보 모터는 컴퓨터와 센서로부터 오는 지령에 대해 높은 위치 정밀도와 정확한 속도제어가 가능해 자동화 시스템에서 중요한 부분으로 사용된다. 본 논문에서는 선형추진 BLDC모터로부터 얻어지는 파라메터를 추정하여 정현여자에 의해 구동되는 방식을 제안했다. 파라미터 추정은 제어기의 게인 튜닝과 외란 관측기를 통해 이루어졌다. 이러한 것을 가능하게 하기 위해 DSP(TMS320F240)를 사용하여 시스템을 구성 하였으며 FOC(Field Oriented Control)방식을 적용하였다. 본 시스템에 사용 된 TMS320F240은 A/D Converter와 PWM 발생부, 다수의 IO Port를 내장하고 있어 서보모터 제어에 유용하게 사용될 수 있는 프로세서이다.

• Journal of Power Electronics
• /
• 제4권4호
• /
• pp.237-245
• /
• 2004

In this paper, a two-switch high frequency flyback transformer linked zero voltage soft switching PWM DC-DC power converter implemented for distributed DC- feeding power conditioning supplies is proposed and discussed. This switch mode power converter circuit is mainly based on two main active power semiconductor switches and a main flyback high frequency transformer linked DC-DC converter in which, two passive lossless quasi-resonant snubbers with pulse current regeneration loops for energy recovery to the DC supply voltages composed of a three winding auxiliary high frequency pulse transformer, auxiliary capacitors and auxiliary diodes for inductive energy recovery discharge blocking due to snubber capacitors are introduced to achieve zero voltage soft switching from light to full load conditions. It is clarified that the passive resonant snubber-assisted soft switching PWM DC-DC power converter has some advantages such as simple circuit configuration, low cost, simple control scheme, high efficiency and lowered noises due to the soft switching commutation. Its operating principle is also described using each mode equivalent circuit. To determine the optimum resonant snubber circuit parameters, some practical design considerations are discussed and evaluated in this paper. Moreover, through experimentation the practical effectiveness of the proposed soft switching PWM DC-DC power converter using IGBTs is evaluated and compared with a hard switching PWM DC-DC power converter.

• Journal of Power Electronics
• /
• 제7권3호
• /
• pp.181-190
• /
• 2007

This paper presents a novel circuit topology of a DC bus line series switch and parallel snubbing capacitor-assisted soft-switching PWM full-bridge inverter type DC-DC power converter with a high frequency planar transformer link, which is newly developed for high performance arc welding machines in industry. The proposed DC-DC power converter circuit is based upon a voltage source-fed H type full-bridge soft-switching PWM inverter with a high frequency transformer. This DC-DC power converter has a single power semiconductor switching device in series with an input DC low side rail and loss less snubbing capacitor in parallel with the inverter bridge legs. All the active power switches in the full-bridge arms and DC bus line can achieve ZCS turn-on and ZVS turn-off transition commutation. Consequently, the total switching power losses occurred at turn-off switching transition of these power semiconductor devices; IGBTs can be reduced even in higher switching frequency bands ranging from 20 kHz to 100 kHz. The switching frequency of this DC-DC power converter using IGBT power modules can be realized at 60 kHz. It is proved experimentally by power loss analysis that the more the switching frequency increases, the more the proposed DC-DC power converter can achieve a higher control response performance and size miniaturization. The practical and inherent effectiveness of the new DC-DC converter topology proposed here is actually confirmed for low voltage and large current DC-DC power supplies (32V, 300A) for TIG arc welding applications in industry.

• 조명전기설비학회논문지
• /
• 제16권3호
• /
• pp.74-83
• /
• 2002

본 논문은 전력설비에 조기적용이 예상되는 초전도한류기의 파라메타를 정의하고 앞으로 개발방향을 제시하기 위하여 한류기의 동작원리, 특성 및 계통조기적용가능성들을 근거로 파라메타의 특성을 비교 ·평가하였다. 또한 한류기의 계통적용효과를 분석하기 위하여 SFCL이 기간 특고압 모델계통에 도입한 경우를 상정하여 3선지락 고장에서 저항형과 유도형 SFCL의 도입 효과에 대하여 RTDS (Real Time Digital Simulation)/EMTDC(Electromagnetic Transient DC)로 시뮬레이션하였다. 특히 저항형과 유도형의 한류효과의 비교 평가, 모선전압의 저하 억제 및 계통과 한류기의 파라메타와의 관련성에 대하여 검토하였다.

• 한국조명전기설비학회:학술대회논문집
• /
• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
• /
• pp.399-402
• /
• 2006

This paper presents a new circuit topology of dc bus line switch-assisted half-bridge soft switching PWM inverter type dc-dc converter for arc welder. The proposed power converter is composed of typical voltage source half-bridge high frequency PWM inverter with a high frequency transformer link in addition to dc bus line side power semiconductor switching devices fer PWM control scheme and capacitive lossless snubbers. All the active power switches in the half-bridge arm and dc bus lines can achieve ZCS turn-on and ZVS turn-off commutation operation and consequently the total turn-off switching losses can be significantly reduced. As a result, a high switching frequency of using IGBTs can be actually selected more than about 20 kHz. The effectiveness of this new converter topology is proved for low voltage and large current dc-dc power supplies such as arc welder from a practical point of view.