• Transactions of the Korean Society of Mechanical Engineers
• /
• v.12 no.4
• /
• pp.682-693
• /
• 1988

In this paper, a method of dynamic modeling is proposed for a hydraulic power transmission with Merrite-Wilson gear train and a computer simulation program for dynamic analysis of the power transmission is developed. Using this computer program the transient characteristics during the gear change are observed and the influence of transmission design parameters and hydraulic control parameters are analysed. Through this result of study a criteria for the good shift quality is derived.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.40 no.6
• /
• pp.397-402
• /
• 2016

To produce adequate electricity in nuclear and thermal power plants, an optimal amount of steam should be supplied to a generator connected to high- and low-pressure steam turbines. A turbine output control device, which is a special steam valve employed to supply or interrupt the steam to the turbine, is operated using a hydraulic servo actuator. In power plants, the performance of servo actuators is degraded by the air generated from the hydraulic system, or causes frequent failures owing to an increase in the wear of the seal. This is due to the seal being burnt as generated heat using the produced compressed air. Some power plants have exhausted air using a fixed orifice, and thus they encounter power loss due to mass flow exhaust. Failures are generated in hydraulic pumps, electric motors, and valves, which are frequently operated. In this study, we perform modeling and analysis of the load-sensing air-exhaust valves, which can be passed through very fine flow under normal use conditions, and exhaust mass flow air at the beginning stage as with existing fixed orifices. Then, we propose a method to prevent failures due to the compressed air, and to ensure the control accuracy of hydraulic servo actuators.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.675-676
• /
• 2013

• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10a
• /
• pp.1172-1177
• /
• 1993

Dynamic characteristics of a hydraulic power supply are studied theoretically and computationally. The transfer function between the supply pressure and the load flow is derived considering relief valve dynamics, accumulator dynamics, and flow line dynamics. Frequency responses and time responses are obtained in many conditions using the transfer function and nonlinear mathematical model respectively.

• Journal of the Korean Society for Precision Engineering
• /
• v.4 no.1
• /
• pp.74-82
• /
• 1987

딥 드로오잉 시의 소재누르기판의 힘을 펀치의 변위 혹은 힘의 임의의 함수로서 제어 시킬 수 있는 서브프레스장치 및 유압장치를 제작하고 제어용 프로그램을 작성하여 시 험하였다. 제작한 장치를 인스트론 시험기에 설치하고 제어용 프로그램을 IBM퍼스널 컴퓨터를 사용하여 실행시킨 결과, 기계 제어 부분은 어셈블러언어로, 계산 부분은 고급 언어로 프로그램을 작성하여 링크시킨 후에 컴파일링하여 사용하는것이 제어의 응답성 및 정확도를 향상시킬 수 있음이 판명되었다. 또한, 소재누르기판의 힘의 제어에 필요한 이론 및 예비 결과들도 제시하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2018.10a
• /
• pp.235-237
• /
• 2018

In spite of the superiority of the sliding method in the building construction field, the AC induction motor servo control device is used as the power control technology in the building construction field in order to improve the problems of the hydraulic power control method, thereby contributing to the precision control and the productivity improvement. Based on Induction Motor Servo Controller, we proposed the development of a mobile sliding method using a complex combination of PC and MITY (MS) Servo.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1995.10a
• /
• pp.254-260
• /
• 1995

본 연구에서는 제어 알고리듬 적용면에서 가속도 계측이 보다 용이한 점을 고려하여 가속도가 포함된 가속도-속도-변위 되먹임 제어 알고리듬을 개발하고, 이를 유압식 능동 질량구동장치에 적용하여 능동제어시스템의 성능을 실증적으로 검토한다. 이 때 능동제어시스템의 구성요소들의 동특성을 시스템 모델링에 포함하여 제어력을 산정함으로써 시간 지연의 영향을 효과적으로 보상하는 방안을 제시한다.

• Journal of the Korean Society for Precision Engineering
• /
• v.18 no.10
• /
• pp.127-133
• /
• 2001

In this study, the effect of the factors of a hydraulic modulator of ASMS was analysed. The modeling of ASMS was presented and the equation of ASMS was derived from the modeling. With this background, GUI analysis tool was developed. After the verification of the reasonability of simulation, the response of a hydraulic modulator is investigated through simulation of modeling. With this simulation, each behavior was predicted with changing the various parameters and determined the influenced factors to apply the designing process.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 1997.11a
• /
• pp.3-3
• /
• 1997

미사일 수직발사 시스템은 공간을 작게 차지하고 간편하여 각국이 선호하고 있다. 그러나 수직발사 초기에는 매우 낮은 속도로 상승하므로 Fin의 공력이 발생하지 않기 때문에 추력방향을 직접제어하지 않으면 안된다. 추력방향 제어장치는 Gimbal, Jet Vane, Jet Tab, Secondary Injection 등 여러 방식이 있으나 Jet Vane Type의 추력 방향 제어장치는 응답이 빠르고 경량화가 가능하며 후방 Fin과의 연동 및 작동 후 분리가 가능하다는 장점으로 인해 수직발사 미사일의 초기 방향제어에 주로 사용한다. 이 장치는 Vane이 화염 속에서 직접 구동되므로 고내열성 재료의 기술이 필요하며 미사일의 전체 System에 요구되는 Side Force를 발생시키기 위한 Vane의 최대 받음각 및 회전속도를 결정해야 한다. 따라서 초음속 유동해석을 통해서 Vane의 받음각에 대한 Side Force와 Torque를 계산하며, 구조해석을 통해 Side Force가 가해지는 동안의 Housing의 굽힘, 비틀림 하중 등을 계산하였다. 또한 Controller는 기존의 유압방식보다도 소형이며 복잡하지 않고 가격이 싼 DC Motor와 감속기를 이용하여 빠른 응답성에 부합토록 설계하였다. 본론에서는 성능과 관련된 초기 요구조건에 대한 최적설계의 변수들을 해석하고. 그에 따른 개발사양, 개발 과정, 구조, 시험방법 등에 대해 고찰하고자 한다.

• Aerospace Engineering and Technology
• /
• v.6 no.2
• /
• pp.164-170
• /
• 2007

In this paper, the development results of electromechanical TVC actuation system is described in the aspect of design, analysis, manufacturing and test. The kinds of prime power for TVC actuation system is classified by the variety of propulsion system of launch vehicle. The electric power by battery is the sole candidate for prime power of TVC actuation system at the view point of feasible domestic infra technologies for the present. The characteristic analysis study is performed between electromechanical and electrohydraulic actuation system with respect to power efficiency, performance and weight efficiency. The electromechanical actuation system has superiority of power and weight efficiency according to less opportunity of power conversion process.