• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(1)
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• pp.201-205
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• 2004

A method for driving and position sensing of TSRM(Toroidal Switched Reluctance Motor) using the search coil is presented in this paper. Position information of the rotor is essential for SRM drives. The rotor position sensor such as an opto-interrupter or high performance encoder is generally used for the estimation of rotor position. However, these discrete position sensors not only add complexity and cost to the system but also tend to reduce the reliability of the drive system. In order to solve these problems, in the proposed method, rotor position detection is achieved using the voltage waveforms induced by the time varying flux linkage in the search coils, and then the appropriate phases are excited to drive the SRM. But the search coil EMF is generated only when the motor rotates. Therefore the rotor position sensing method at standstill is also suggested.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1994년도 추계학술대회 논문집
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• pp.3-8
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• 1994

This paper presents a practical method of measuring the cutting force milling process by sensing the feed-drive servo motor current,avoiding the use of a dynamomenter. The relation between the cutting force and the servo motor currents is obtained after the feed-drive system of machining center is modelled. In order to measure the cutting force indirectly, the cutting force in the feed-drive system is regrared as a disturbance, and a disturbance estimator is designed using Kalman filter. A horizontal type machining center is used in the experimental study. A comparison is made between the cutting force measured from the dynamometer and the servo motor current.

• 센서학회지
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• 제22권6호
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• pp.387-392
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• 2013

Camera rigs for shooting 3D video are classified as manual, motorized, or fully automatic. Even in an automatic camera rig, the process of Stereoscopic 3D (S3D) video capture is very complex and time-consuming. One of the key time-consuming operations is capturing the distance parameters, which are near distance, far distance, and convergence distance. Traditionally these distances are measured by tape measure or triangular indirect measurement methods. These two methods consume a long time for every scene in shot. In our study, a compact laser distance sensing system with long range distance sensitivity is developed. The system is small enough to be installed on top of a camera and the measuring accuracy is within 2% even at a range of 50 m. The shooting time of an automatic camera rig equipped with the laser distance sensing system can be reduced significantly to less than a minute.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.4-6
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• 2003

Optical signals from an object may vary at different conditions caused by differences in light source and sensor position. Knowledge of these variations is necessary to enable calibration of the satellite images and confirmation of the sun and sensor angles influences of the spectral signals from the objects. With the use high -resolution Ikonos$^{TM}$ multi-angular images, the bi- directional reflectance effects of mangrove trees were observed when three datasets were compared. The influence of bi- directional reflectance may affect the accuracy of interpreting satellite imagery and obtaining biophysical parameters mangrove and other vegetation by indirect means.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.434-437
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• 2001

Generally, a switched reluctance motor (SRM) drive requires a rotor position sensor for commutation and current control. However, this position sensor causes an increase for cost and size of motor drive. In this paper, a sliding mode observer is proposed for indirect position sensing in SRM drive. This estimated rotor position is used for the electric commutation of the machine phases. The paper includes a design approach and operating performance based on the proposed sliding mode observer.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.179-183
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• 1999

This paper describes a new method for indirect sensing of the rotor position in switched reluctance motors using fuzzy logic algorithm. Through a novel fuzzy algorithm, the complete SRM magnetizing characterization is first constructed, and then used to estimate the rotor position. And also, the optimized phase is selected by phase selector. To demonstrate the promise of this approach, the proposed rotor position estimation algorithm is simulated for variable speed range.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.488-492
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• 1998

Indirect sensing of the rotor position of permanent magnet brushless DC motors contains position error. Such measuring error can be attenuated by adopting Kalman filter. In this paper, the cause of measuring error is analyzed and the design technique of Kalman filter is described. Experimental results show that the proposed sensorless drive exerts superior performances.

• 전기학회논문지P
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• 제59권2호
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• pp.135-140
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• 2010

This paper presents a sensorless speed control of BLDC Motor using terminal voltage of the one phase. Rotor position information is extracted by indirectly sensing the back EMF from only one of the three terminal voltages for a three-phase BLDC motor. Depending on the terminal voltage sensing rotor position, active filter is used for position information. This leads to a significant reduction in the component device of the sensorless circuit. Therefore this is a advantage for the cost saving and size reduction. With indirect sensing methods based on detection of the terminal voltage that require active filtering, the position information needs the six divider section by PLL circuit, the binary counter and johnson counter by the EPLD. Finally, this algorithm can estimate the rotor position information similar to Hall-sensor sticked the three-phase BLDC motor. As a result, the method described that it is not sensitive to filtering delays, allowing the motor to achieve a good performance over a wide speed range. In addition, a simple starting method and a speed estimation approach are also proposed. Experimental and simulation results are included to verify the proposed scheme.

• Journal of Power Electronics
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• 제5권3호
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• pp.173-179
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• 2005

In this paper, a very low cost and robust sensing method for the rotor position of a TSRM(Toroidal Switched Reluctance Motors) is described. Position information of the rotor is essential for SRM drives. The rotor position sensor such as an opto-interrupter or high performance encoder is generally used for the estimation of rotor position. However, these discrete position sensors not only add complexity and cost to the system but also tend to reduce the reliability of the drive system. In order to solve these problems, in the proposed method, rotor position detection is achieved using voltage waveforms induced by the time varying flux linkage in the search coils, and then the appropriate phases are excited to drive the SRM. But the search coil's EMF is generated only when the motor rotates. Therefore the rotor position sensing method using squared Euclidean distance at a standstill is also examined. The simulation and experimental results are presented to verify the performance of the proposed method in this paper.

• 대한교통학회지
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• 제28권3호
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• pp.157-167
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• 2010

교통량, 속도, 밀도의 3가지 교통류 지표 중 밀도는 혼잡을 잘 나타내는 지표이다. 밀도를 측정하는 방안은 직접적으로 수집하는 방안과 수집자료를 활용하여 간접적으로 수집하는 방안이 있다. 직접적인 측정법은 대상구간의 교통류를 항공기나 고층건물에서 촬영하여 밀도를 직접적으로 구하는 것이나, 기상과 도로조건 및 비용상의 문제로 인하여 광범위한 사용에는 한계가 있다. 본 논문에서는 두 개의 지점검지기를 이용하여 밀도를 측정할 수 있는 방법을 제시하였다. 또한, 순간밀도, 평균밀도, 측정간격이라는 개념을 정리하고 가상시뮬레이션(Paramics Application Programming Interface) 기능을 활용하여 자료를 생성한 후 측정간격이 도로조건(측정구간길이별, 차로별, 서비수준별)별로 구간밀도정확도에 미치는 영향을 분석하였다.