• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.353-357
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• 2017

대탄도탄 방어 무기체계의 핵심인 직격요격비행체 위치자세제어시스템(DACS, Divert Attitude Control System) 의 연구 동향 및 주요 기술에 대해 서술하였다. DACS의 기본 구성을 정의하고 사용 연료별 DACS의 종류 및 운영개념, 특징을 정리하였다. 고체(SM3 Block IB/IIA) 및 액체(THAAD) 연료를 적용한 대표적인 무기체의 운용 개념 및 주요 특징을 살펴보았다. 향후 방어무기체계의 전략적 차원에서 다양한 형태의 DACS의 연구가 필요할 것으로 판단된다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권3호
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• pp.127-133
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• 2005

Korean multi-propulsion system consists of a synchronous alternator driven by a gas turbine driving synchronous alternator coupled to a rectifier - DC link - DC/DC converter and traction system based on modification of the G7 high-speed train. The simulation modules include turbine engine system, alternator, rectifier, DC/DC converter and power management module. Simulation for the multi-propulsion system such as a modular is presented in order to confirm the system stability for loads with uncertain input impedances and control loop speeds. This paper deals with various simulation modules with a specific control loop to help the development of the real lame-scaled system.

• 전력전자학회논문지
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• 제21권5호
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• pp.388-395
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• 2016

Electric vehicles (EV) and hybrid EVs (HEV) are designed and manufactured by GM, Toyota, Honda, and Hyundai motors. The propulsion system design process for EV requires integrating subsystem designs into an overall system model to maximize the performance of a given propulsion architecture. Therefore, high-power density and high-torque density are important attributes required for EV applications. To improve torque and power density, propulsion motors are designed for saturation during high-torque operation. The nonlinearity associated with core saturation is modeled by incorporating the cross-coupling inductances, which also behave nonlinearly. Furthermore, in EV environments, the battery is directly connected to the DC link, and the battery changes depending on the state of charge. It will be onerous if as many optimal current commands as different $V_{dc}$ were made. This paper presents the optimal current commands in the various operating condition and the current control technique in EV environments.

• International Journal of Aeronautical and Space Sciences
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• 제6권1호
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• pp.61-70
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• 2005

The currently developed propulsion system(PS) is composed of propellant tank, valves, thrusters, interconnecting line assembly and thermal hardwares to prevent propellant freezing in the space environment. Comprehensive engineering analyses in the structure, thermal, flow and plume fields are performed to evaluate main design parameters and to verify their suitabilities concurrently at the design phase. The integrated PS has undergone a series of acceptance tests to verify workmanship, performance, and functionality prior to spacecraft level integration. After all the processes of assembly, integration and test are completed, the PS is integrated with the satellite bus system successfully. At present, the severe environmental tests have been carried out to evaluate functionality performances of satellite bus system. This paper summarizes an overall development process of monopropellant propulsion system for the attitude and orbit control of LEO(Low Earth Orbit) observation satellite from the design engineering up to the integration and test.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2006년도 제27회 추계학술대회논문집
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• pp.7-10
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• 2006

발사체가 정확하게 주어진 궤도에 인공위성을 투입시키기 위해서는 Pitch, Yaw, Roll의 3축을 제어하는 정밀한 자세 및 제어 시스템이 필요하다. 현재 사용되고 있는 자세 제어 시스템은 크게 Cold gas 방식과 단일 및 이원 추진제를 사용하는 액체 추진 기관이 일반적으로 발사체에 사용되고 있다. 위와 같은 추진제를 사용하는 추력 제어시스템의 장단점을 분석을 통하여 시스템의 단순성 및 구조비와 운영 측면에서 향후 개발될 발사체 상단에 적용할 수 있는지를 판단하고자 하는 것이 목적이다.

• 한국추진공학회지
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• 제19권2호
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• pp.73-80
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• 2015

Apollo Mission이 종료된지 거의 반세기가 지났지만, 지금도 Saturn V 발사체의 기술의 복원과 개량을 위한 연구가 활발하게 진행되고 있다. 본 연구에서는 Saturn V 발사체의 1단 로켓(S-IC)의 개발 과정과 엔진 퍼지, 포고현상 억제 방법, 연료탱크 가압 방식, 유압 및 공압 시스템의 운용 방식 등에 대한 특징들에 대해 조사하였다. S-IC의 추진기관 시스템의 특징에 대한 이해는 발사체 시스템의 이해를 도울 수 있고, 향후 발사체 개발 시에 시간, 비용 등의 절감 효과를 가져다 줄 수 있는 유용한 참고 자료가 될 것이라 예상된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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• pp.476-488
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• 1998

The study was carried out about the development of the propulsion and the control systems toy Korean High Speed Train. The propulsion system was studied to run the maximum operating speed of 350km/h. The capacity of the main equipments is decided for the train to run the maximum operating speed of 350km/h with one Ike of 2 power cars, 4 motorized trailers and 14 intermediate trailers. The control system was studied to two parts the supply and the control of high and low voltages used at train. The performance study of control system would be continued for interface with other systems.

• 드라이브 ㆍ 컨트롤
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• 제18권4호
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• pp.59-64
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• 2021

In this paper, a mathematical pressure dynamics model for a variable thrust solid propulsion system with an electric actuator was derived from the mass conservation of gas. To solve the problem induced by modeling uncertainties in the propellant model and the dead zone of the actuator, a nonlinear pressure controller combined with a nonlinear disturbance observer was designed using a mathematical model of the system. The simulation results showed that the proposed pressure controller could reduce tracking errors compared to another conventional nonlinear controller even in situations where input disturbances were present.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.800-805
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• 2005

In this study, control schemes are proposed for a propulsion system of TTX(Tilting Train eXpress). In developed traction converter, unity power factor control, compensation method of dc link voltage have been applied. Output current of converter contains harmonic ripple at twice input ac line frequency, which causes a ripple in the dc link voltage so that beatless control is developed in inverter system to reduce the pulsating torque current. This system is verified by the system modelling and prototype test.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제25회 추계학술대회논문집
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• pp.426-430
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• 2005

통신해양기상위성(COMS)는 국내 최초로 개발되는 3축 안정화 복합위성으로 2008년에 지구정지궤도(GEO, Geostationary Earth Orbit)에 발사될 예정이다. 통신해양기상위성 추진시스템은 위성체의 지구정지궤도 진입, 자세 및 궤도 제어/조정을 위하여 요구되는 추력과 토오크를 제공한다. 본 논문은 통신해양기상위성 추진시스템의 시스템 설계 및 주요 부품의 성능에 관하여 기술하고자 한다.