• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.265-267
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• 2008

As generally recognized, the driving performance of a SRM at higher speed will be degraded due to the effects of back electromagnetic force (EMF). This phenomenon can be improved via voltage boosting. So in this paper an improved converter of enhancing the performance for four-phase switched reluctance motor (SRM) is proposed. By using one additional capacitor and switches, an extra controllable boosted voltage can be produced during the rise and fall periods of a motor phase current. Then this active boosted voltage can reduce the effect of EMF on the current, particularly at high speeds. The attractive features of the proposed converter are as follows: obtaining boosted voltage to improve performance of SRM with same numbers of switch and diode as asymmetric converter, having higher control flexibility and capability of boosting voltage compared with passive boosting converters, possessing lower cost and simple control in comparison with existing active boosting converters. The performances of the proposed circuit are verified by the simulation and experiment results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.986-989
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• 2008

Recently the agitator are being widely used in the machine plan in order to increase the petrochemical industry. The agitator normally consist of impeller, shaft, hub, reduction gear and the driving motor. It is one of the key design issue to confirm that the vibration caused by the rotation of the shaft should not coincide with the natural frequency of the shaft itself. And petrochemical industry as well as plants have been in operation for long period beyond their original design lives. In this paper the vibration of Ox-Reactor Agitator is measured for check machine condition. The result of diagnosis and solution is discussed in this paper.

• 제어로봇시스템학회논문지
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• 제13권2호
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• pp.79-85
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• 2007

The skid-steering method that applied a number of mobile robot currently is very effective in narrow area. But it contains several problems of its natural properties, slip, occurred by different direction between vehicle's driving and wheel's rotary. From this thesis we want to suggest suitable structure of $6{\times}6$ skid steering wheeled vehicle and method of driving by analyzing the behavior of $6{\times}6$ skid-steered wheeled vehicle by engineering analytical method

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.132-135
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• 2008

This paper presents a PLL(Phase Lock Loop) control method for speed control of high speed miniature BLDCM(Brushless DC Motor) using hall sensor. The Proposed PLL based speed control method uses a only phase shift between reference pulse signal according to speed reference and actual pulse signal from hall sensor. It doesn't use any speed calculation, and calculates a direct current reference from phase shift. The current reference is changed to reduce the phase shift between reference and actual pulse. So the actual speed can keep the reference speed. The proposed control scheme is very simple but effective speed control is possible.

• 한국정밀공학회지
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• 제23권2호
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• pp.172-180
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• 2006

Although there existed many types of manual/power hybrid wheelchairs, their use was not widespread because of their inconvenience in converting drive system and in folding frames. To carry a wheelchair in the car or to convert driving methods, some hard work of disassembling or exchanging wheels was required for most of currently available hybrid wheelchairs. In this study, the standard foldable manual wheelchair was reformed to a power wheelchair by installing the newly developed Axial Flux Permanent Magnet(AFPM) type of brush less direct current(BLDC) motor on each rear hub of wheelchair. This wheelchair could be driven by manual or electric power without exchanging. wheels, thus no additional work was needed for carriage or for power conversion. The developed wheelchair was evaluated for durability, stability, maneuverability, cost, and reliability in accordance with the Korean standards. The results indicated that the developed hybrid wheelchair was good enough for commercialization comparing to other imported wheelchairs.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 1999년도 유체기계 연구개발 발표회 논문집
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• pp.252-256
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• 1999

In this research, the performance predictions of the submersible mixer were investigated. The variation of the performance characteristics by changing the impeller design parameters were discussed through the flow calculation results by using a commercial program, FLUENT. The performance of the submersible mixers is related to the velocity diffusion profiles downstream of the impeller and also the required input motor power to mix the fluid. In this study, the various design parameters such as the number of blade, the hub and tip diameters, the impeller blade profiles and revolution speed of the blades were taken for the fixed values. The blade sweep direction, the chord length distribution along with the radius of the blade and the inlet blade angle were changed to make different testing models. The flow calculation results show the effect of the changed design parameters on the performance of the submersible mixers and also give some helpful information for designing more efficient submersible mixers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 심포지엄 논문집 정보 및 제어부문
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• pp.77-79
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• 2004

Because robot hardware architecture generally is consisted of a few sensors and motors connected to the central processing unit, this type of structure is led to time consuming and unreliable system. For analysis, one of the fundamental difficulties in real-time system is how to be bounded the time behavior of the system. When a distributed control network controls the robot, with a central computing hub that sets the goals for the robot, processes the sensor information and provides coordination targets for the joints. If the distributed system supposed to be connected to a control network, the joints have their own control processors that act in groups to maintain global stability, while also operating individually to provide local motor control. We try to analyze the architecture of network-based humanoid robot's leg part and deal with its application using the CAN(Controller Area Network) protocol.

• 대한공업교육학회지
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• 제31권2호
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• pp.364-380
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• 2006

본 연구는 모델링 오차를 갖는 유연구조물의 잔류진동을 억제하는 입력설계에 대한 방법이다. 개루프 제어방법으로 시간지연방법을 이용하여 여러 가지 형태로 설계된 입력을 사용하여 유연구조물의 강체운동과 잔류진동을 억제함을 시뮬레이션과 실험을 통해 비교 확인해 보았다. 또한 모델 오차에 대한 강인성 측면에서도 해석적으로 개루프 시스템에서 검토해 보았다. 여기서 사용된 입력설계(Input-Shaping) 방법은 일련의 임펄스 콘볼류션을 이용하여 진동이 제어되는 입력을 설계한다. 실린더 모양의 허브와 양쪽에 유연한 날개 모양을 가진 모델이 실험에 이용되었으며 제안된 입력설계 명령과 설계되지 않은 명령에 대한 강체운동과 구조물의 잔류진동을 측정하여 입력설계 방법의 효과를 확인하였다. 날개모양의 구조물은 길고 유연하여 운동 상태에서 낮은 주파수 진동을 수반하는 구조물이다. 또한, 적절히 설계된 입력이 폐루프 제어시스템의 입력으로 사용할 때의 응답을 개루프 제어시스템의 응답과 비교하기 위해 해석적 방법을 통해 살펴보았다. 제어의 목적은 강체의 빠른 정착시간, 유연 구조물의 빠른 잔류진동 감쇄, 모델의 불확실성에 대한 강인성 등을 검토해 보는 것이다.

• 한국항만경제학회지
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• 제35권4호
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• pp.147-168
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• 2019

본 논문은 평택당진항의 자동차 물류 클러스터 구축방안을 모색하는데 있다. 평택당진항은 자동차 관련 부가가치 물류서비스를 바탕으로 활성화되고 발전할 필요가 있기 때문이다. 각 지자체마다 앞다퉈 자동차 관련 산업단지 육성에 나서고 있다. 또한 향후 국산 자동차 수출 전망은 어둡지만 평택당진항을 비롯한 여러 항만이 수출입과 환적 자동차를 유치하기 위해 부두시설을 확충하는 등 자동차 항만으로서 위상을 확보하기 위해 부단히 노력하고 있다. 평택당진항은 현재 1위 자동차 항만으로서 자동차 물류 클러스터를 구축하기 위한 좋은 여건을 갖추고 있다. 쌍용자동차와 기아자동차, 그리고 삼성전자와 LG전자가 가까이 위치하고 있고, 향후 항만배후단지 개발을 통하여 충분히 자동차 물류 클러스터 구축에 소요되는 부지를 용이하게 확보할 수 있기 때문이다. 단순한 물류 거점으로서만이 아니라 다양한 문화와 체험이 가능한 자동차 물류거점을 조성함으로써 미래 모빌리티 발전에 적절하게 대응할 수 있도록 함으로써 평택당진항의 지속가능한 발전을 도모할 수 있다.

• 한국자동차공학회논문집
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• 제19권2호
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• pp.1-11
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• 2011

The skid-steering method that applied a number of mobile robot currently is extremely effective in narrow area. But it contains several problems such as its natural properties, slip, occurred by different direction between vehicle's driving and wheel's rotary. Through this paper, suitable control algorithm of $6{\times}6$ skid steering wheeled vehicle and its driving methods are proposed by analyzing the behavior $6{\times}6$ skid-steered wheeled vehicle model designed by engineering analysis strategy. To do this, based on a behavior of designed driving system, required torque and other performance of in-wheel type motor system are considered, and finally control algorithm for each wheel is proposed and simulated using this model. To test the proposed vehicle system, driver model is designed using PID closed loop system and included in the total driving control algorithm. The Performance of designed vehicle model is verified by using DYC (Direct Yaw Control) cornering mode and slip mode control to follow the steering input which are essential to evaluate the driving performance of $6{\times}6$ vehicle. Proposed modeling strategy and control method will be implemented to the real $6{\times}6$ in-wheel drive type vehicle.