• 제목/요약/키워드: Output saturation

검색결과 202건 처리시간 0.022초

무추력 비행체를 대상으로 한 적응 통합 유도제어기 설계 (Integrated Guidance and Control Design Based on Adaptive Neural Network for Unpowered Air Vehicle)

  • 김부민;성덕용;성재민;김병수
    • 제어로봇시스템학회논문지
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    • 제15권1호
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    • pp.15-22
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    • 2009
  • The guidance controller of the conventional aircraft consists of inner-loop (autopilot) and outer-loop (guidance). If the guidance controller can be designed as an integrated guidance and control (IGC), the various advantages exist. The integrated guidance and control formulation can compensate for the effect of autopilot lag. An integrated approach also helps avoid the iterative procedure involved in tuning the guidance and autopilot subsystems, if designed separately. Integrated design is also less susceptible to saturation and stability problems. This paper presents an approach to IGC design for the unpowered air vehicle with the only flaperon using a combination of adaptive output feedback inversion and backstepping techniques. Adaptive neural networks are trained online with available measurements to compensate for unmodeled nonlinearities in the design process.

Estimation of Output Voltage and Magnetic Flux Density for a Wireless Charging System with Different Magnetic Core Properties

  • Park, Ji Hea;Kim, Sang Woo
    • Journal of Magnetics
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    • 제18권2호
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    • pp.105-110
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    • 2013
  • The design model and key parameters of the material design for the control of induced magnetic flux at the near-field and efficient power transfer in a modified wireless power transfer (WPT) system with a large air gap of wireless electric vehicles were investigated through analytical simulations for magnetic vector and time-domain transient analysis. Higher saturation magnetic core with low core loss induced a stronger vertical magnetic field by the W-type primary coil in the WPT system with a gap of 20 cm at 20 kHz, which is shown from the vector potentials of the magnetic induction. The transient analysis shows that the higher magnetic fluxes through the pick-up cores lead to a linear increment of the alternating voltage with a sinusoidal waveform in the non-contact energy transfer system.

Current Saturation Improvement of Poly-Si TFTs for Analog Circuit Integration

  • Nam, Woo-Jin;Han, Sang-Myeon;Lee, Hye-Jin;Han, Min-Koo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.289-292
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    • 2005
  • New poly-Si TFTs have been proposed and fabricated in order to increases the output channel resistance ($r_o$). The counter-doped($p^+$) source is tied to the $n^+$ source and is extended into the channel region so that it employs the reverse bias depletion in the channel. As $V_{DS}$ is increased, the depletion width is increased and the effective channel width is reduced. Therefore, the output current saturates well and the $r_o$ is increased successfully. The proposed CMOS devices may improve the amplifier gain of data driver in active-matrix displays

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단상 PV-배터리에너지저장시스템의 출력전류 오프셋 보상기법 (Offset Compensation Method of Output Current in Single Phase PV-Baterry Energy Storage System)

  • 주재연;서현욱;조영훈;최규하
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2013년도 전력전자학술대회 논문집
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    • pp.130-131
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    • 2013
  • In this paper, it suggests offset compensation method of output current in single phase PV-BES system which is connected with grid. The algorithm applied removes grid's frequency ingredient using a notch filter and it extracts only DC offset current. It can reduce problems as saturation of power transformer cause by DC current when it is indoctrinated to grid.

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고출력 응용을 위한 영구자석 매입형 동기 릴럭턴스 전동기의 특성해석 (Characteristic Analysis of Permanent Magnet Assisted Synchronous Reluctance Motorfor High Power Application)

  • 장영진;김상길;신흥교;박성준;이중호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 B
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    • pp.914-916
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    • 2004
  • In this paper, finite element analysis for a PMASynRM is presented and the characteristic analysis of inductance and torque is performed under the effect of saturation. The focus of this paper is characteristic analysis of d and q-axis inductances and torque according to magnetizing quantity of interior permanent magnet for PMASynRM. The d and q-axis current component ratios, load angles of a PMASynRM are investigated quantitatively on the basis of the proposed analysis method and the experimental test. Comparisons are given with output characteristic curves of normal SynRM and those according to the load in PMASynRM, respectively. And it is confirmed that the proposed model results in high output power performance.

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HLS 색상 공간에서 동영상의 안개제거 기법 (Video Haze Removal Method in HLS Color Space)

  • 안재원;고윤호
    • 한국멀티미디어학회논문지
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    • 제20권1호
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    • pp.32-42
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    • 2017
  • This paper proposes a new haze removal method for moving image sequence. Since the conventional dark channel prior haze removal method adjusts each color component separately in RGB color space, there can be severe color distortion in the haze removed output image. In order to resolve this problem, this paper proposes a new haze removal scheme that adjusts luminance and saturation components in HLS color space while retaining hue component. Also the conventional dark channel prior haze removal method is developed to obtain best haze removal performance for a single image. Therefore, if it is applied to a moving image sequence, the estimated parameter values change rapidly and the haze removed output image sequence shows unnatural glitter defects. To overcome this problem, a new parameter estimation method using Kalman filter is proposed for moving image sequence. Experimental results demonstrate that the haze removal performance of the proposed method is better than that of the conventional dark channel prior method.

궤도민감도 분석에 기반하여 복입력 전력시스템 안정화 장치(Dual-Input PSS)의 비선형 파라미터 최적화 기법 (Optimal Tuning of Nonlinear Parameters of a Dual-Input Power System Stabilizer Based on Analysis of Trajectory Sensitivities)

  • 백승묵;박정욱
    • 전기학회논문지
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    • 제57권6호
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    • pp.915-923
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    • 2008
  • This paper focuses on optimal tuning of nonlinear parameters of a dual-input power system stabilizer(dual-input PSS), which can improve the system damping performance immediately following a large disturbance. Until recently, various PSS models have developed to bring stability and reliability to power systems, and some of these models are used in industry applications. However, due to non-smooth nonlinearities from the interaction between linear parameters(gains and time constants of linear controllers) and nonlinear parameters(saturation output limits), the output limit parameters cannot be determined by the conventional tuning methods based on linear analysis. Only ad hoc tuning procedures('trial and error' approach) have been used. Therefore, the steepest descent method is applied to implement the optimal tuning of the nonlinear parameters of the dual-input PSS. The gradient required in this optimization technique can be computed from trajectory sensitivities in hybrid system modeling with the differential-algebraic-impulsive-switched(DAIS) structure. The optimal output limits of the dual-input PSS are evaluated by time-domain simulation in both a single machine infinite bus(SMIB) system and a multi-machine power system in comparison with those of a single-input PSS.

A Multi-Stage CMOS Charge Pump for Low-Voltage Memories

  • Kim, Young-Hee;Lim, Gyu-Ho;Yoo, Sung-Han;Park, Mu-Hun;Ko, Bong-Jin;Cho, Seong-Ik;Min, Kyeong-Sik;Ahn, Jin-Hong;Chung, Jin-Yong
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -1
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    • pp.369-372
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    • 2002
  • To remedy both the degradation and saturation of the output voltages in the modified Dickson pump, a new multistage charge pump circuit is presented in this paper. Here using PMOS charge-transfer switches instead of NMOS ones eliminates the necessity of diode-configured output stage in the modified-Dickson pump, achieving the improved voltage pumping gain and its output voltages proportional to the stage numbers. Measurement indicates that VOUT/3VDD of this new pump circuit with two stages reaches to a value as high as 0.94V even with low VDD=1.0 V, strongly addressing that this scheme is very favorable at low-voltage memory applications.

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근감각-색·음 변환을 위한 ARM 기반 임베디드시스템의 구현 (Implementation of ARM based Embedded System for Muscular Sense into both Color and Sound Conversion)

  • 김성일
    • 한국콘텐츠학회논문지
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    • 제16권8호
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    • pp.427-434
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    • 2016
  • 본 논문은 인간이 인지할 수 있는 감각들 중 인체의 회전, 방향 변화 및 움직임의 정도를 알 수 있는 근감각에서 시각 및 청각 요소로의 변환 알고리즘을 이용하여 ARM Cortex-M4에 기반한 실시간 임베디드시스템으로 구현한 방법에 초점을 맞추었다. 근감각의 입력 방식으로는 자세측정장치(AHRS : Attitude Heading Reference System)를 이용해 롤(Roll), 피치(Pitch) 및 요(Yaw) 값을 실시간 획득하고, 이들 각각의 색을 표현하는 HSI 컬러 모델의 명도(Intensity), 색상(Hue) 및 채도(Saturation)에 대응하여 변환하였다. 최종 컬러신호는 HSI 에서 RGB 컬러모델로 변환하여 획득하였다. 또한, 근감각의 세 가지 입력 값들을 음을 표현하는 요소인 옥타브(Octave), 음계(Scale) 및 음의 세기(Velocity)에 대응하여 변환한 값을 MIDI(Musical Instrument Digital Interface)를 이용해 사운드를 합성하여 출력하였다. 출력 컬러신호 및 사운드를 분석한 결과, 근감각 입력 신호가 제안한 변환 방식에 따라 실시간으로 정확하게 색과 음으로 변환, 출력됨을 확인하였다.

중급 규모 가스화 복합발전 플랜트의 $NO_x$ 저감 방식이 성능 및 환경특성에 미치는 영향에 관한 평가 연구 (Evaluation Study on the Effects of $NO_x$ Reduction Techniques on the Performance and the Emission Characteristics of Medium Size Gasification Combined Cycle Plant)

  • 이찬;서제영
    • 에너지공학
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    • 제10권4호
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    • pp.363-369
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    • 2001
  • 중급규모의 가스화 복합/열병합 플랜트의 공정설계와 성능평가를 수행하였다. 설계된 플랜트 공정을 바탕으로 가스터빈 연소기에 비포화 또는 포화된 질소를 분사시키거나 가스연료를 포화시키는 여러 가지 $NO_x$ 저감 기술들을 시도하여, $NO_x$ 저감 기법이 $NO_x$ 배출량에 미치는 영향과 플랜트의 출력, 효율 및 안정성에 미치는 영향을 동시에 검토하였다. 가스 연료의 포화보다는 질소의 분사를 통한 $NO_x$ 저감효과가 더욱 현저하며, 질소분산 시 포화된 질소를 사용하는 경우 $NO_x$ 저감 효과는 더욱 향상되었다. 또한 $NO_x$ 저감 기법의 적용은 $NO_x$ 배출량의 감소와 더불어 플랜트의 출력 및 효율 향상도 수반하나, 가스터빈의 불안정한 운전을 초래할 수도 있었다.

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