• 제어로봇시스템학회논문지
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• 제11권10호
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• pp.870-879
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• 2005

This paper presents that a transient response can be characterized by certain parameters which are correlated to characteristic polynomial coefficients. These are characteristic ratios and characteristic pulsatances by P. Naslin [4]. We have developed an approach to control directly the transient response. Firstly, speed of the response can be controlled by reconstruction form via multipliable characteristic pulsatances. Secondly, overshoot is controlled by reconstruction form via multipliable characteristic ratios. These formulas can be independently characterized by the system overshoot and the response time to a step input.

• Tribology and Lubricants
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• 제28권6호
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• pp.265-271
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• 2012

In the preceding Part I study, for improving the unbalance response vibration of a large PRT motor-generator rotor fundamentally by design, a series of design analyses were carried out for bearing improvement by retrofitting from original plain partial journal bearings, applied for operation at a rated speed of 1,800 rpm, to final tilting pad journal bearings. To satisfy evenly key basic lubrication performances such as the minimum lift-off speed and maximum oil-film temperature, a design solution of 5-pad tilting pad journal bearings and maximizing the direct stiffness by about two times has been achieved. In this Part II study, a detailed rotordynamic analysis of the large PRT motor-generator rotor-bearing system will be performed, applying both the original plain partial journal bearings and the retrofitted tilting pad journal bearings, to confirm the effect of rotordynamic vibration improvement after retrofitting. The results show that the rotor unbalance response vibrations with the tilting pad journal bearings are greatly reduced by as much as about one ninth of those with the plain partial journal bearings. In addition, for the tilting pad journal bearings there exist no critical speed up to the rated speed and just one instance of a concerned critical speed around the rated speed, whereas for the plain partial journal bearings there exist one instance of a critical speed up to the rated speed and two instances of concerned critical speeds around the rated speed.

• 한국강구조학회 논문집
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• 제18권6호
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• pp.769-782
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• 2006

상시 운행 열차는 운행 속도 대역폭이 한정되어 있기 때문에 속도에 따른 교량의 동적응답 특성 파악에는 한계가 있다. 따라서 본 연구에서는 교량상을 통과하는 열차 속도와 교량의 동적응답의 상관관계를 파악하기 위하여 실운행 디젤 기관차 1량에 의한 증속실험을 실시하였다. 가속도 응답특성 분석을 위하여 지점부를 제외한 전구간에 걸쳐 등간격으로 7개의 수직가속도와 중앙부에 1개의 수평가속도계를 부착하였다. 교량의 중앙부에는 연직방향과 횡방향 거동특성 파악을 위하여 수직 변위계, 수평 변위계, 휨변형률계를 각각 1개씩 설치하였다. 실험 차량을 대상 교량의 중앙부와 지점부에 정적재하 후 5km/h부터 90km/h까지 10km/h씩 증속하였고, 각 속도 대역별로 2회씩 반복하여 실험을 실시하였다. 실측 데이터의 필터링 방법에 따른 진동 평가 방법의 적절성을 검토하였고, 연직방향 진동가속도 대비 횡방향 진동수준을 평가하였으며, 속도에 따른 처짐, 변형률 및 윤중변동 특성을 검토하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1979년도 하계 전자.전기연합학술발표회논문집
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• pp.166-167
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• 1979

Performances of three computational algorithms for one-dimensional frequency filtering are compared and tradeoffs are studied. If the size of the filter impulse response is small, it is well-known that the conventional convolution is superior than the FFT convolution. If the size of the impulse response is large, it was suggested that the recursive filter might be competitive in terms of speed to the FFT convolution. We, therefore, have developed an computational, algorithm for the recursive filter to compare the speed advantages over the FFT convolution and the results are presented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.176-178
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• 2006

This paper is intended to research the speed response of switched reluctance motor (SRM) using sliding mode control method when load is changing. The simulation compare only control by PI controller with control by PI controller and sliding mode controller. It compare with speed response using MATLAB/SIMULINK.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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• pp.371-374
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• 1990

This paper presents the speed control of dc motor based on deadbeat response. The deadbeat response is that the output reaches the final value in the minimum possible settling time and stays there. This results demonstrate that the output reaches final value in one sampling time for the unsaturated region, and in one sampling time after getting free from the saturation state for the saturated region.

• ETRI Journal
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• 제6권2호
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• pp.3-9
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• 1984

This paper proposes an optimal control scheme for shaft position control using microcomputer-based state-variable feedback. In this scheme a performance index was set up in order to ruduce the overshoot and improve the steady- state response speed, and the time-variant system parameters were identified in real time for optimal control. As a result of experiment, the over-shoot was not occured and the response speed was improved 2. 9 times about proportional control. This scheme improves the performance against the variation of load and sampling time, and adding the integral control in this scheme can reduce the steady-state error without any change in response time.

• 소음진동
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• 제3권1호
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• pp.57-63
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• 1993

The dynamic response of stiffened rectangular plate subjected to a concentrated force or mass moving at constant speed is analyzed by using finite- element method. Stiffened plates are modelled as an assembly of isotropic thin plate elements and equivalent Euler beam ones, in which the beam elements represent the stiffener effects concentrated at the attached lines of stiffeners to the plates. The Newmark's time integration method is used to obtain the dynamic response of stiffened plates. Numerical examples are given to verify the validity of the presented method and also to investigate the effects of speed and moving mass on the dynamic characteristics of stiffened plates.

• Journal of Power Electronics
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• 제16권3호
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• pp.1076-1086
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• 2016

PI controllers are one of the most widely used controllers in industrial control systems due to their simple algorithms and stability. The parameters K_p and K_i determine the performance of the system response. The response is expected to improve by increasing the gain of the PI controller. However, too large a gain will accelerate the speed response and cause vibrations, which is not what is expected. This paper proposes a way to suppress vibrations by detecting the vibration frequency and extracting the vibration signal as a compensation to the speed feedback. Additionally, in order to improve its disturbance rejection ability, a low-order disturbance observer is proposed. This paper also explains the operation principle of the proposed method by analyzing the transfer function and it describes the design of the controller parameters in detail. Simulation and experimental results are provided to verify the merits of the proposed method. These results also show the good performance of the proposed method. It has a rapid response and suppresses vibrations.

• 한국정보통신학회논문지
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• 제2권3호
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• pp.295-302
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• 1998

본 논문에서는 한계계단 응답특성을 이용하여 영구자석헝 동기전동기의 속도 제어계에 대한 새로운 자동동조 PI(Proportional Integral) 제어기를 설계하였다. 과도응답 기간동안 소위 한계입력이라고 하는 계단입력을 인가하여 Pㅑ 제어기의 자동동조를 위한 정보를 얻기 위한 기법을 제안한다. 시스템 파라메터 추정과 동시에 속도제어가 온라인으로 이루어지는데, 이것은 시스템의 불확실성에도 불구하고 한계입력에 의해서 얻어진 시스템 파라메터 정보가 연속적으로 PI 제어기에 적용될 수 있다는 것이다. 제안된 자동동조 알고리즘은 단조증가 계단응답 특성을 갖는 영구 자석형 동기전동기의 속도제어에 대한 시뮬레이션과 실험결과를 통하여 그 유효함을 확인하였다.