• 항공우주시스템공학회지
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• 제3권3호
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• pp.17-23
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• 2009

KARI SUAV (Smart Unmanned Aerial Vehicle) program is currently on the phase of ground and flight test. SUAV is a tilt rotor aircraft having the capability of vertical take-off/landing and high speed forward flight. The SUAV rotor system is 3-bladed, gimbaled hub type, which is not common for conventional helicopter configuration. In this paper, detailed procedure and method of rotor pitch rigging, tracking and balancing were described based on the experience of SUAV ground test.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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• pp.406-410
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• 2010

본 논문은 초고속 비행체의 특정 위치에 정압력을 측정하여 속도, 받음각 등 유동 데이터를 효과적으로 획득할 수 있는 유동 데이터 획득 및 처리 알고리즘에 대해 제시하였다. 기존의 공기 유동데이터 획득시스템과는 다르게 센서 여유(redundancy) 및 오류 검출 기능을 지니고 있으며 전산유동해석(CFD)을 통해 미리 획득한 데이터를 적용한 알고리즘을 적용하였다. 상용 프로그램인 매트랩 및 시뮬링크를 사용하여 알고리즘에 대해 검증하였다.

• 한국군사과학기술학회지
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• 제21권2호
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• pp.188-194
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• 2018

Recently a supercavitating underwater vehicle moving at high speed over 200 knots has been of interest for its practical advantage of the dramatic drag reduction. Many experimental and numerical studies have been explored, however most of the studies deal with the case of uniform flows. In this paper, we investigated physical behaviors of the artificial supercavity in a periodic gust flow. Experiments were carried out at a cavitation tunnel of the Chungnam National University(CNUCT), which is equipped to remove the gas supplied from outside of the tunnel. We devised an experimental apparatus generating vertical and horizontal gust flows, and investigated the supercavity formations at different periodic mode of the incoming flow.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1310-1312
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• 2004

현재, 고속철도차량의 국내기술확보를 위해 한국형 고속전철이 개발되어 단품시험, 완성차시험, 공장시험 등을 통해 기본적인 성능을 확인한 후 현재는 본선시운전 시험을 실시하고 있다. 시제차량의 성능 및 기능을 종합적이고 효율적으로 확인하기 위해 고속철도 시운전시험시 상시 계측시스템을 시제차량에 설치하여 운영하고 있다. 본 논문에서는 상시계측시스템을 이용하여 보조전원장치에 대한 성능평가와 고장진단을 실시한 것에 대하여 연구하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.1294-1296
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• 2003

For this research, we developed the hardware and software of the measurement system for on-line test and evaluation. The software controls the hardware of the mesurement data and acts as interface between users and the system hardware. In this paper, we is studied for Aux. Block performance of railway vehicle. In order to this test is developed signal conversion system. Using this system. we obtained important result for battery voltage, Aux. Block temperature.

• 한국자동차공학회논문집
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• 제12권1호
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• pp.174-183
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• 2004

A program to analyze the performance characteristics of a hydraulic shimmy damper for automotive steering system was developed in this study. Dimensionless mathematical equations of the dynamics of shimmy damper for forward and reverse fluid flows were derived respectively and incorporated into the Simulink models. The program was validated by comparing the results of simulation and experiments for various frequencies of upstream ripple pressures into the damper. Low-pass filter characteristics of the shimmy damper at reverse flow was demonstrated which means that the shimmy damper could alleviate the high speed ripple pressures induced by the unbalance oscillation of tire in vehicle driving. The parameter sensitivity analysis was also conducted to identify the dominant parameters for the damper performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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• pp.206-207
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• 2007

We developed a measurement system for on-line test and evaluation of performances of KHST. The measurement system is composed of software part and hardware part. Perfect interface between multi-users is possible. A new method to measure temperature was applied to the measurement system. By using the system, fault diagnosis and performance evaluation of electric equipment in Korean High Speed Train was conducted during test running.

• 조명전기설비학회논문지
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• 제28권7호
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• pp.48-54
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• 2014

This paper discusses study of torque ripple minimization employing an improved TDF(torque distribution function)-based instantaneous torque control to reduce acoustic noise and vibration problem of the SRM. As the flux linkage of the SRM is a nonlinear function of phase current and rotor position, design of optimal controller for the SRM is quite complicated. Hence, an accurate mathematical model considering the nonlinearity of the SRM is required. An improved TDF based torque control has been proposed in order to reduce the toque ripple at high speed operation. Dynamic simulation using Matlab/Simulink as well as Finite Element Analysis is presented. A prototype SRM for electric vehicle traction has been manufactured to validate the experimental results comparing the dynamic simulation results.

• 한국군사과학기술학회지
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• 제16권6호
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• pp.867-880
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• 2013

The development for a high speed underwater vehicle has been demanded for a long time, and it is possible to realize using supercavitation. This paper introduces the main technologies that are necessary to develop a supercavitating rocket system, such as "Supercavitation" and "Hydroreactive technology", and describes the operating concepts and principles for its components specifically. Russia has obtained the key technologies of supercavitation and hydroreactive fuel technology for the first time. Russia has developed a supercavitating rocket torpedo, Shkval, and it was in service since 90's. Iran collaborated with Russia to develop a supercavitating rocket torpedo 'Hoot' and finished a test recently. This paper describes the analysis results related with the cavitator based on the technical reports for Shkval of Russia and Hoot of Iran.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2015년도 전력전자학술대회 논문집
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• pp.207-208
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• 2015

팬(fan), 펌프(pump), 블로어(blower), 전기 자동차(electric/hybrid vehicle), 전동차와 같은 다양한 분야에서 3상 전동기의 고속 운전에 대한 요구가 증대되고 있다. 일반적으로 3상 전동기가 정격 속도 이상의 고속에서 운전하기 위해서는 회전자 자속(rotor flux)의 크기를 운전 상황에 따라 감소시키는 약자속(flux weakening) 제어가 필수적이다. 유도 전동기의 회전자 자속 기준 벡터 제어 시의 약자속 운전은 자속 성분 전류의 크기를 제어하여 유도 전동기의 고속 운전을 가능하게 하는데, 이러한 전류 제어 기반의 약자속 제어는 그 구조가 복잡하고, 제어기 이득 선정에 따른 동특성(dynamic)이 영향울 받는 문제점을 가지고 있다. 본 논문에서는 이러한 단점을 개선하기 위한 순시적 약자속 제어 방법을 제안하고 3.7kW 유도 전동기를 이용한 실험을 통하여 제안된 방식의 성능을 검증한다.