• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2019년도 전력전자학술대회
• /
• pp.139-141
• /
• 2019

Capacitive power transfer has an advantage in the simplicity of the energy link structure. So, the conventional phase -shift full bridge sometime is not always the best choice because of its complexity and high cost. On the other hand, the link capacitance is usually very low and requires high-frequency operation, but, the series resonant converter loses zero-voltage switching feature in the light load condition, which makes the switching loss high especially in CPT system. The paper proposes a new low-cost topology based on asymmetric half-bridge to achieve simplicity as well as wide zero voltage switching range. The design procedure is presented, and circuit operations are analyzed and verified by simulation.

• 한국전기전자재료학회논문지
• /
• 제37권2호
• /
• pp.133-140
• /
• 2024

This study offers a comprehensive evaluation of the role and impact of advanced power semiconductors in solar module systems. Focusing on silicon carbide (SiC) and gallium nitride (GaN) materials, it highlights their superiority over traditional silicon in enhancing system efficiency and reliability. The research underscores the growing industry demand for high-performance semiconductors, driven by global sustainable energy goals. This shift is crucial for overcoming the limitations of conventional solar technology, paving the way for more efficient, economically viable, and environmentally sustainable solar energy solutions. The findings suggest significant potential for these advanced materials in shaping the future of solar power technology.

• Journal of information and communication convergence engineering
• /
• 제22권2호
• /
• pp.159-164
• /
• 2024

This study aimed to develop an advanced anomaly-detection system tailored for solar power distribution panels using thermal imaging cameras to ensure operational stability. It addresses the imperative shift toward digitalized safety management in electrical facilities, transcending the limitations of conventional empirical methodologies. Our proposed system leverages a faster R-CNN-based artificial intelligence model optimized through meticulous hyperparameter tuning to efficiently detect anomalies in distribution panels. Through comprehensive experimentation, we validated the efficacy of the system in accurately identifying anomalies, thereby propelling safety protocols forward during the fourth industrial revolution. This study signifies a significant stride toward fortifying the integrity and resilience of solar power distribution systems, which is pivotal for adapting to emerging technological paradigms and evolving safety standards in the energy sector. These findings offer valuable insights for enhancing the reliability and efficiency of safety management practices and fostering a safer and more sustainable energy landscape.

• 지구물리와물리탐사
• /
• 제19권1호
• /
• pp.11-19
• /
• 2016

나머지 정적보정 기법중에서 가장 많이 쓰이는 주행시간 분해기법과 겹쌓기제곱 최대화기법의 적용성을 육상 탄성파자료에서 비교 검토하였다. 모든 발파점과 수신점에 대한 임의의 나머지 정적보정값(시간차이)과 무작위 잡음이 포함된 모델자료에서 겹쌓기제곱 최대화기법은 주행시간 분해기법에 비해 흐트러진 반사 이벤트를 정확히 정렬시키고 보정과정에서 출력된 발파점과 수신점의 정적보정 그래프가 입력된 값과 거의 같은 진폭으로 역전된다는 점에서 신호대잡음이 작은 자료의 반사면 향상에 보다 효과적이었다. 나머지 정적보정에 적합한 입력인자(최대허용 시간차이, 상관창, 반복횟수)들은 공통중간점 자료외에 공통발파점 겹쌓기자료와 공통수신점 겹쌓기자료에 대한 연속 테스트를 거쳐 효과적으로 진단할 수 있었다. 나머지 정적보정에 앞서 송수신점의 높이보정 및 풍화대 깊이보정을 실시하여 장파장 시간차이를 제거하고 진동수-파수 필터링, 예측곱풀기, 시간변화 빛띠흰색화로 잡음을 줄여 교차상관의 오차를 최소화시킨다. 또한 나머지 정적보정후 수직시간차 역보정을 거쳐 속도를 재분석하여 겹쌓기한 결과 저류층을 포함한 반사면들의 향상된 연속성 및 분해능을 확인할 수 있었다.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(1)
• /
• pp.231-234
• /
• 2003

This paper presents a novel high frequency transformer linked full-bridge type soft-switching phase-shift PWM control scheme DC-DC power converter, which can be used as power conditioner fur small-scale fuel cell power generation system. Using full-bridge soft-switching DC-DC converter topology makes possible to use low voltage high performance MOSFETs to achieve high efficiency of the power conditioner. A tapped inductor filter is implemented in the proposed soft-switching converter topology to achieve soft-switching PWM constant high frequency operation for a wide load variation range. to minimize circulating and idling currents without using additional resonant circuit and auxiliary power switching devices. The practical effectiveness of the proposed soft-switching DC-DC converter is verified in laboratory level experiment with 1 kW 100kHz breadboard setup using power MOSFETs. Actual efficiency of 94-96$\%$ is obtained for the wide load range

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2013년도 추계학술대회 논문집
• /
• pp.151-152
• /
• 2013

본 논문에서는 DAB(Dual Active Bridge)로 구성된 양방향 절연형 DC-DC 컨버터의 제어 기법인 SPS(Single Phase Shift)와 DPS(Dual Phase Shift)를 양방향 OBC(On-Board Charger)의 충전 및 방전모드에 적용한다. 그리고 각 모드의 입출력 조건에 따라 전력 반도체 소자에서 발생되는 손실을 PSIM 시뮬레이션과 수학적 분석을 통해 예측하고, 이를 비교 분석한다.

• 천문학회지
• /
• 제37권5호
• /
• pp.471-476
• /
• 2004

We propose an analytical model to estimate the influence of a merger on the thermal SZ effect. Following observations we distinguish between subsonic and transonic mergers. Using analytical velocity fields and the Bernoulli equation we calculate the excess pressure around a moving subcluster for an incompressible subsonic gas. Positive excess around the stagnation point and negative excess on the side of the subcluster lead to characteristic signatures in the SZ map, of the order of $10\%$ compared to the unperturbed signal. For a transonic merger we calculate the change in the thermal spectral SZ function, resulting from bow shock accelerated electrons. The merger shock compression factor determines the power law tail of the new non-thermal electron population and is directly related to a shift in the crossover frequency. This shift is typically a few percent towards higher frequencies.

• 전자공학회논문지B
• /
• 제33B권4호
• /
• pp.217-225
• /
• 1996

This paper describes a high power resonant inverter for diagnostic X-ray generators using zero-voltage soft-switching technology. The system consists of a step-down chopper, a resonant phase-shift PWM inverter, a hihg-voltage diode, and high voltage cables a smoothing DC capacitor. The inverter makes use the leakage inductance of the hihg-voltage transformer and external capacitor as resonant components. The rectified input voltage is controlled by a step-down chopper with input voltage compensator. The output regualtion is obtained by a resonant phase-shift PWM inverter with the digital feedback controller using DSP (digital signal processor), resulting in fast rising time and wide output voltage variation. The theoretical results are correlated with results from an experimental prototype of a 7-kVp, 300mA (21kW).

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
• /
• pp.157-162
• /
• 2003

This paper presents the loss analysis of Phase-Shift Full-Bridge Converter. Full-Bridge DC/DC Converter presented in this paper used a phase shift control in the primary side to achieve ZVS (Zero-Voltage-Switching) for main switch. Phase-Shaft Full-Bridge converter have an effect on the high power system. This paper analyses the loss of each component and the various losses in the circuit assessed. The result of the analysis are verified using 2.5kW, 50kHz prototype.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2017년도 추계학술대회
• /
• pp.13-14
• /
• 2017

1차와 2차측의 위상 변조를 이용하는 Dual Active Bridge (DAB) 형태의 직렬 공진형 양방향 컨버터는 이미 구현되었다. 하지만 이는 좁은 영전압 스위칭 범위를 가지고 경부하시 전력변환 효율을 떨어뜨린다. 본 논문은 Sinple Phase Shift (SPS)와 Extended Phase Shift (EPS)를 사용하는 양방향 직렬 공진형 컨버터를 제안하고 이를 이용하여 전부하 구간동안 소프트 스위칭을 얻고자 한다. 정방향 및 역방향 전력 변환에 따른 영전압 스위칭의 조건을 분석하고 공진 탱크와 제어 자유도를 조절 방법에 대해 분석하고자 한다. 제안하는 분석 및 디자인 방법은 500 W 직렬 공진형 컨버터를 통해 검증하였다.