• 제목/요약/키워드: In-Rush Current

검색결과 32건 처리시간 0.025초

SSPA용 전원공급기의 돌입전류 보호회로 분석 및 설계 (Analysis and Design of the In-Rush Current Protection Circuit for SSPA Power Supply)

  • 박상현;박동철;김대관
    • 한국군사과학기술학회지
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    • 제11권5호
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    • pp.5-11
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    • 2008
  • Recently developed radars use the solid-state power amplifier to amplify the RF signal. The stability of RF signal directly depends on that of the electric power. So the stable and reliable electric power should be needed. When the electric power switch is tuned on for the first time in order to operate the radar system, the in-rush current is generated because of the capacitive characteristic. The excess in-rush current breaks the element. Therefore, the analysis about the in-rush current to design the electric power system is necessary. In this paper, modeling and simulation on the whole power system is carried out and the necessity of limiting the in-rush current is verified. After the analysis, the circuit to limit the in-rush current is designed and examined to verify the analysis. The circuit is good enough to limit the in-rush current.

단상유도전동기의 돌입전류저감을 위한 제어기 설계 (Design of Controller for Reducing In-Rush Current of Single-Phase Induction Motor)

  • 박수강;백형래;이상일
    • 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.

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PC 파워 서플라이용 비대칭 하프브리지 DC/DC 컨버터의 초기 구동시 돌입전류 제거 기법 (Start-up In-rush Current Reduction Technique of Asymmetrical Half-Bridge DC/DC Converter for PC Power Supply)

  • 김재국;이성세;오원식;김정은;문건우;길창현;조자룡
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2006년도 전력전자학술대회 논문집
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    • pp.251-253
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    • 2006
  • This paper presents a start-up in-rush current reduction technique of asymmetry half-bridge DC/DC converter for PC power supply. The proposed converter is composed center-tapped half-bridge converter with blocking capacitor. The proposed converter can reduce the severe in-rush current when the proposed converter is power up. The validity of this study is confirmed from the experimental results.

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DC/DC 스위칭 컨버터 특성 (DC/DC Switching Converter Characteristics)

  • 최영진;김상준;김태경
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.743-746
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    • 1999
  • In this paper, Flyback type DC/DC Switching Converter was designed, analyzed and fabricated. Worst Case Analysis(WCA) was peformed with Mathcad program and presents circuit simulation results for the in-rush current limit circuit. The value of the maximum OFF voltage stress is 131.84V, it is less than device specification(200V). The switching frequency(nominal case) and duty cycle at the wont case analysis are 75KHz and 34.62%, respectively. The maximum in-rush current presents 0.5A Those results show a possibility for use in space

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배전계통에서 발생하는 돌입전류와 고장전류의 특성 비교연구 (The Study of characteristic comparison with inrush and fault current occurred in distribution system)

  • 오용택;김진성
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2001년도 학술대회논문집
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    • pp.51-58
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    • 2001
  • This paper gives a type and high-frequency waves analysis of in-rush current cab be flowed into distribution automatic machine to be installed in distribution line in order to use minimizing operation error of failure indicator to have been issue recent with obtaining high-frequency component that can be different from current. The in-rush and fault current data studied in this paper is to be surveyed actually in USA distribution system substation line of Bryan Power Company near Texas A. M University, to be occurred high impedance fault.

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유도성 부하의 돌입전류저감을 위한 제어기에 관한 연구 (A Study on the Controller for Reducing of In-Rush Current of Inductive Load)

  • 박수강;조금배;백형래;임양수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 B
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    • pp.1345-1347
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    • 2000
  • This paper presents a new method to reducing inrush current and energy saving of capacitor starting 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.

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YouTube videos provide low-quality educational content about rotator cuff disease

  • Kunze, Kyle N.;Alter, Kevin H.;Cohn, Matthew R.;Vadhera, Amar S.;Verma, Nikhil N.;Yanke, Adam B.;Chahla, Jorge
    • Clinics in Shoulder and Elbow
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    • 제25권3호
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    • pp.217-223
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    • 2022
  • Background: YouTube has become a popular source of healthcare information in orthopedic surgery. Although quality-based studies of YouTube content have been performed for information concerning many orthopedic pathologies, the quality and accuracy of information on the rotator cuff have yet to be evaluated. The purpose of the current study was to evaluate the reliability and educational content of YouTube videos concerning the rotator cuff. Methods: YouTube was queried for the term "rotator cuff." The first 50 videos from this search were evaluated. Video reliability was assessed using the Journal of the American Medical Association (JAMA) benchmark criteria (range, 0-5). Educational content was assessed using the global quality score (GQS; range, 0-4) and the rotator cuff-specific score (RCSS; range, 0-22). Results: The mean number of views was 317,500.7±538,585.3. The mean JAMA, GQS, and RCSS scores were 2.7±2.0, 3.7±1.0, and 5.6±3.6, respectively. Non-surgical intervention content was independently associated with a lower GQS (β=-2.19, p=0.019). Disease-specific video content (β=4.01, p=0.045) was the only independent predictor of RCSS. Conclusions: The overall quality and educational content of YouTube videos concerned with the rotator cuff were low. Physicians should caution patients in using such videos as resources for decision-making and should counsel them appropriately.

PCRAM Flip-Flop Circuits with Sequential Sleep-in Control Scheme and Selective Write Latch

  • Choi, Jun-Myung;Jung, Chul-Moon;Min, Kyeong-Sik
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제13권1호
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    • pp.58-64
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    • 2013
  • In this paper, two new flip-flop circuits with PCRAM latches that are FF-1 and FF-2, respectively, are proposed not to waste leakage during sleep time. Unlike the FF-1 circuit that has a normal PCRAM latch, the FF-2 circuit has a selective write latch that can reduce the switching activity in writing operation to save switching power at sleep-in moment. Moreover, a sequential sleep-in control is proposed to reduce the rush current peak that is observed at the sleep-in moment. From the simulation of storing '000000' to the PCRAM latch, we could verify that the proposed FF-1 and FF-2 consume smaller power than the conventional 45-nm FF if the sleep time is longer than $465{\mu}s$ and $95{\mu}s$, respectively, at $125^{\circ}C$. For the rush current peak, the sequential sleep-in control could reduce the current peak as much as 77%.

암치료용 레이저 시스템 개발 (The development of laser system for cancer)

  • 이동진;김주명;김선학;임현수
    • 한국광학회:학술대회논문집
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    • 한국광학회 2001년도 하계학술발표회
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    • pp.154-155
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    • 2001
  • A laser system for therapy of cancer is proposed in this paper. In order to accuracy and statistical output control we used the constant current control method and designed the power source to protect the resonator from the over -current, rush-current and electrical fault. The most important things are the radiation type for cancer therapy in laser system, we developed the radiation type of cw, pulse, and burst pulse. The experimental result show that laser beam power increase linearly from 100mW to 300mW for input current increasing and the exposure time.

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권철심형 원형단면 코어의 비교 분석 (Comparison and Analysis of round shape core of transformer)

  • 심민석;공정식;김철호;오철수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 B
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    • pp.1024-1026
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    • 2003
  • This paper deals with the characteristic analysis of round shape core of transformer compared with conventional EI core transformer. The round shape has specific configuration to reduce leakage magnetic flux. Characteristics such as B-H characteristic curve and in-rush current, etc. are compared.

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