• 제목/요약/키워드: pulse type excitation

검색결과 23건 처리시간 0.033초

Rocking response of self-centring wall with viscous dampers under pulse-type excitations

  • Zhang, Lingxin;Huang, Xiaogang;Zhou, Zhen
    • Earthquakes and Structures
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    • 제19권3호
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    • pp.215-226
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    • 2020
  • A self-centering wall (SCW) is a lateral resistant rocking system that incorporates posttensioned (PT) tendons to provide a self-centering capacity along with dampers to dissipate energy. This paper investigates the rocking responses of a SCW with base viscous dampers under a sinusoidal-type pulse considering yielding and fracture behaviour of the PT tendon. The differences in the overturning acceleration caused by different initial forces in the PT tendon are computed by the theoretical method. The exact analytical solution to the linear approximate equation of motion is also provided for slender SCWs. Finally, the effects of the ductile behaviour of PT tendons on the rocking response of a SCW are analysed. The results demonstrate that SCWs exhibit two overturning modes under pulse excitation. The overturning region with Mode 1 in the PT force cases separates the safe region of the wall into two parts: region S1 with an elastic tendon and region S2 with a fractured tendon. The minimum overturning acceleration of a SCW with an elastic-brittle tendon becomes insensitive to excitation frequency as the PT force increases. After the plastic behaviour of the PT tendon is considered, the minimum overturning acceleration of a SCW is increased significantly in the whole range of the studied wg/p.

리니어 펄스 모터에서 치 형상과 기자력 불평형이 정추력 특성에 미치는 영향 (Effect of Tooth Shape and Unbalanced M.M.F on Static Thrust Force Characteristics of Linear Pulse Motor)

  • 이동주;이은웅;김성헌;김성종
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제49권3호
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    • pp.131-137
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    • 2000
  • 2 phase 8 pole HB-type(flat-type) Linear Pulse Motor can be used as the high precision position actuator because of its many advantages (simple control circuit, high stiffness characteristics, etc). Also, using the microstep drive, its noise and vibration can be reduced considerably and positional resolution may be increased further. But, $20^{\circ}$tapered tooth shape to reduce the normal force have an much effect on the static thrust force characteristics. And, because of hybrid-type LPM, interaction between the permanent magnet and the excitation current have an effect on the various characteristics of LPM. Hence, in this paper, the effect of tooth shape on static thrust force characteristics was analyzed using the air gap permeance by finite element method. For analyzing the effect of unbalance between the m.m.f of permanent magnet and the m.m.f of excitation current, unbalanced m.m.f coefficient $\sigma$ were introduced with the permenace matrix and switching matrix.

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SMR구동을 위한 적정여자전압 고정스위칭각 제어방식 (Proper excitation voltage and fixed switching angle control scheme for SRM drive)

  • 안영주;안진우;조철제;황영문
    • 대한전기학회논문지
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    • 제45권1호
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    • pp.54-59
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    • 1996
  • As the current shape of SRM is of pulse type and changed by the motor parameters and drive conditions, the influences on the drive efficiency by control method are more than other types of motors. In this paper, a proper excitation condition to drive a SRM with high efficiency is proposed and tested. It is derived from the conditions that the phase current of a SRM is to be flat-topped at various drive. The saturation effect of magnetic circuit is accounted for more accurate analysis. Experimental tests are executed to verify the proposed excitation method. This drive system is easy to commutate and also advantageous in reducing torque ripple. (author). 6 refs., 10 figs., 1 tab.

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Dynamic response of post-tensioned rocking wall-moment frames under near-fault ground excitation

  • Feng, Ruoyu;Chen, Ying;Cui, Guozhi
    • Earthquakes and Structures
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    • 제15권3호
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    • pp.243-251
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    • 2018
  • The dynamic responses of a rocking wall-moment frame (RWMF) with a post-tensioned cable are investigated. The nonlinear equations of motions are developed, which can be categorized as a single-degree-of-freedom (SDOF) model. The model is validated through comparison of the rocking response of the rigid rocking wall (RRW) and displacement of the moment frame (MF) against that obtained from Finite Element analysis when subjected ground motion excitation. A comprehensive parametric analysis is carried out to determine the seismic performance factors of the RWMF systems under near-fault trigonometric pulse excitation. The horizontal displacement of the RWMF system is compared with that of MF structures without RRW, revealing the damping effect of the RRW. Frame displacement spectra excited by trigonometric pulses and recorded earthquake ground motions are constructed. The effects of pulse type, mass ratio, frame stiffness, and wall slenderness variations on the displacement spectra are presented. The paper shows that the coupling with a RRW has mixed results on suppressing the maximum displacement response of the frame.

회생형 이중화 PWM 방식의 디지털 여자시스템에 관한 연구 (A Study on the Dual PWM Digital Excitation System of Regeneration Type)

  • 류호선;이주현;임익헌
    • 조명전기설비학회논문지
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    • 제24권9호
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    • pp.79-84
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    • 2010
  • This paper discusses the control of generator field using dual IGBT PWM regeneration method to target brushless synchronous generator. If one of PWM bridges happens to fault, it transfers automatically and can be in charge of full load. Also it has an advantage of the operation which UPS connected in parallel with PWM bridge can supply power to excitation system in condition of main power loss. This PWM system supplies field current to generator in one quadrature operation, regenerates field coil energy to main power supplier in four quadrature operation. We designed, manufactured and applied the first trial product at J-power plant.

Optimum parameters and performance of tuned mass damper-inerter for base-isolated structures

  • Jangid, Radhey Shyam
    • Smart Structures and Systems
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    • 제29권4호
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    • pp.549-560
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    • 2022
  • The optimum damping and tuning frequency ratio of the tuned mass damper-inerter (TMDI) for the base-isolated structure is obtained using the numerical searching technique under stationary white-noise and filtered white-noise earthquake excitation. The minimization of the isolated structure's mean-square relative displacement and absolute acceleration, as well as the maximization of the energy dissipation index, were chosen as the criteria for optimality. Using a curve-fitting technique, explicit formulae for TMDI damping and tuning frequency for white-noise excitation are then derived. The proposed empirical expressions for TMDI parameters are found to have a negligible error, making them useful for the effective design of base-isolated structures. The effectiveness of TMDI and its optimum parameters are influenced by the soil condition and isolation frequency, according to the comparison made of the optimized parameters and response with different soil profiles. The effectiveness of an optimally designed TMDI in controlling the displacement and acceleration response of the flexible isolated structure under real and pulse-type earthquakes is also observed and found to be increased as the inertance mass ratio increases.

2상 8극 HB형 리니어펄스모터의 제어회로구성을 위한 기초연구 (A Basic Study for the Control Circuit of 2-phase 8-pole HB type Linear Pulse Motor)

  • 김성헌;김일중;이은웅
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 A
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    • pp.135-137
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    • 1994
  • In this paper, step response, speed, maximum frequency characteristics of 2-phase, 8-pole, HB type, prototype linear pulse motor(LPM) were investigated with the open loop control system(OLCS) being attached to the LPH. In this experiment, both 1-phase and 1-2 phase excitation types were adopted and microcomputer was used in deal with the data. The results point to some directions for the improvement of the open loop control system.

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RPE 검색을 이용한 CELP 보코더의 불규칙 코드북 검색 (On a Reduction of Codebook Searching Time by using RPE Searching Tchnique in the CELP Vocoder)

  • 김대식
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 1995년도 제12회 음성통신 및 신호처리 워크샵 논문집 (SCAS 12권 1호)
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    • pp.141-145
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    • 1995
  • Code excited linear prediction speech coders exhibit good performance at data rates as low as 4800 bps. The major drawback to CELP type coders is their large computational requirements. In this paper, we propose a new codebook search method that preserves the quality of the CELP vocoder with reduced complexity. The basic idea is to restrict the searching range of the random codebook by using a searching technique of the regular pulse excitation. Applying the proposed method to the CELP vocoder, we can get approximately 48% complexity reduction in the codebook search.

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과도현상 해석을 위한 시간 영역에서의 등가축약법 :프로니 해석기법을 이용한 등가 구동점 임피던스 모델의 구성 (Time domain Reduction Method for Electromagnetic Transients Study: Equivalent Driving-Point Impedance Model using Prony Analysis)

  • 홍준희;박종근
    • 대한전기학회논문지
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    • 제43권4호
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    • pp.687-690
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    • 1994
  • This paper presents a method of obtaining transmission network equivalents from the network's response to the pulse excitation signal. Proposed method is base on Prony signal analysis and jtransfer function identification technique. As a result Thevenin-type of discrete-time filter model can be generated. It can reproduce the driving point impedance characteristic of the network.

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레이저 발진용 세논기체 섬광관의 방전계통해석 (Analysis of Xenon Flash Lamp Discharge System for Laser Excitation)

  • 김영권;이문기
    • 대한전자공학회논문지
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    • 제5권3호
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    • pp.25-30
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    • 1968
  • 세논 섬광관의 방전회로에 관한 특성을 상세히 논했다. 섬광관은 전류에 비전형적이므로 방전회로에 관한 의 비선형 미분방정식을 유도하여 해를 상이형전자 계산기로 구했다. 또한 더욱이 임의의 섬광관에 대한 입력에너지 펄스지속시간 및 모양, 인덕턴스, 콘덴서 그리고 동작전압에 대해 완전히 고찰했다. 아울러 본 해석결과를 이용하면 성광관 방전계통회로를 정확히 설계할 수 있음을 제시했다.

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