• Title/Summary/Keyword: azimuth

Search Result 794, Processing Time 0.026 seconds

Construction of Measuring System for Magnetic Properties Measurement of Azimuth Angle Sensor (방위각센서의 자기특성 측정 장치 제작)

  • Son, Derac
    • Journal of the Korean Magnetics Society
    • /
    • v.24 no.1
    • /
    • pp.22-27
    • /
    • 2014
  • North indicating azimuth angle sensors have been used in airplanes, ships traditionally and nowadays employed in smart phones. For the azimuth and roll angle measurement of the sensor, 3-axis acceleration sensor was added to the 3-axis magnetic field sensor. In this work, we have constructed a measuring system for the measurement of the magnetic field and the angle uncertainty of the magnetic field sensors. Measuring system could be useful not only in non-magnetic laboratory but also in normal laboratory, we constructed small size of 3-axis Helmholtz coils for the compensation environment magnetic field (Earth magnetic field and magnetic field from building) and the generation of magnetic field for the test of magnetic field sensor. The constructed measuring system could compensate environment magnetic field below 10 nT level and generate 3-dimensional magnetic field with magnitude uncertainty of 0.2 % and angle error of $0.2^{\circ}$ within the volume of ${\pm}30mm$ diameter at center of Helmholtz coils. For the conformation of developed measuring system, We tested commercially available 3-axis magnetometer and heading sensor.

Control of a Novel PV Tracking System Considering the Shadow Influence

  • Ko, Jae-Sub;Chung, Dong-Hwa
    • Journal of Electrical Engineering and Technology
    • /
    • v.7 no.4
    • /
    • pp.524-529
    • /
    • 2012
  • This paper proposes a novel control strategy of a PV tracking system considering the shadow influence. If distance of between PV arrays is not enough, shadow can be occurred to PV module. In PV system, if shadow is occurred to PV modules then PV modules operates reverses bias, and will eventually cause hot-spot and loss. To reduce loss by shadow influence, this paper proposes shadow compensation algorithm using distance between arrays and shadow length of array. The distance between arrays is calculated by using azimuth of solar, and length of array shadow is calculated using by altitude of solar. The shadow compensation algorithm proposed in this paper compares distance between arrays and length of array shadow. When the shadow length is longer than the distance between arrays, the algorithm adjusts altitude of array to avoid the shadow effects. The control algorithm proposed in this paper proves validity through compared with conventional algorithm and proposes experiment result.

Time delay control with state feedback for azimuth motion of the frictionless positioning device

  • Jeong, Ho-Seop;Lee, Chong-Won
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1996.10a
    • /
    • pp.385-388
    • /
    • 1996
  • A time delay controller with state feedback is proposed for azimuth motion control of the frictionless positioning device which is subject to the variations of inertia in the presence of measurement noise. The time delay controller, which is combined with a low-pass filter to attenuate the effect of measurement noise, ensures the asymptotic stability of the closed loop system. It is found that the low-pass filter tends to increase the robustness in the design of time delay controller as well as the gain and phase margins of the closed loop system. Numerical and experimental results support that the proposed controller guarantees a good tracking performance irrespective of the variation of inertia and the presence of measurement noise.

  • PDF

A Study on Optimal Design of Photovoltaic System for Efficiency Progress (태양광발전시스템의 효율향상을 위한 최적설계에 관한 연구)

  • Choi, Young-Moon;Lim, Jung-Yol
    • Journal of IKEEE
    • /
    • v.13 no.2
    • /
    • pp.175-180
    • /
    • 2009
  • This paper compare the operation characteristic and optimal design of Photovoltaic system by computer simulation. The operation characteristic of Photovoltaic system are evaluated and analyzed considering system parameters of specifications, installations, inclination, azimuth and surrounding conditions etc. From the basis of these results, this study will intend to develop an evaluation, analysis tool and construct database for optimal design of PV system.

  • PDF

A Study on New PV Tracking System Including Load Dispersion

  • Lee, Sang-Hun;Song, Hyun-Jig;Park, Chan-Gyu;Song, Sung-Geon
    • Journal of international Conference on Electrical Machines and Systems
    • /
    • v.3 no.4
    • /
    • pp.472-480
    • /
    • 2014
  • The In solar power system, the height and azimuth of the sun are important parameters which control generated power magnitude. The tracking method that controls the daily generation magnitude according to latitude and longitude using the two axles is often used in the existing sunlight tracking system today. In this two-axle PV track control system, the self-load is concentrated on one FRAME. It is influenced of the regular load, snow load and the wind load, etc. It is difficult to set up the system in the conventional building. This research is a development about the small-scale economy track device of independent load-dispersing solar generation system. The position tracking algorithm is through new coordinates transformation calculating the height and azimuth of the sun.

INITIAL ACQUISITION PROCEDURE FOR KOMPSAT2 WITH K13ANTENNA

  • Lee Jeong-bae;Yang Hyung-mo;Ahn Sang-il;Kim Eun-kyou
    • Proceedings of the KSRS Conference
    • /
    • 2005.10a
    • /
    • pp.501-504
    • /
    • 2005
  • In general, most incomplete communication link setup between satellite and ground station right after separation from launcher come from less accurate orbital vector ground station uses to track the satellite because only predicted orbital state vector is available during first few orbits. This paper describes the developed procedure for successful initial acquisition for KOMPSAT-2 using scanning functions ofK13 antenna system with predicted orbital information. Azimuth scan, raster scan, spiral scan functions were tested with KOMPSA Tl under intentionally degraded orbital information for antenna operation. Through tests, spiral scan function was decided to be best search scan among 3 scans. Developed procedure can assure the successful acquisition only if azimuth offset and time offset value are within +/-2deg and +/-30sec, respectively.

  • PDF

Sound Source Localization Technique at a Long Distance for Intelligent Service Robot (지능형 서비스 로봇을 위한 원거리 음원 추적 기술)

  • Lee Ji-Yeoun;Hahn Min-Soo
    • MALSORI
    • /
    • no.57
    • /
    • pp.85-97
    • /
    • 2006
  • This paper suggests an algorithm that can estimate the direction of the sound source in real time. The algorithm uses the time difference and sound intensity information among the recorded sound source by four microphones. Also, to deal with noise of robot itself, the Kalman filter is implemented. The proposed method can take shorter execution time than that of an existing algorithm to fit the real-time service robot. Also, using the Kalman filter, signal ratio relative to background noise, SNR, is approximately improved to 8 dB. And the estimation result of azimuth shows relatively small error within the range of ${\pm}7$ degree.

  • PDF

Fiber-optic Ccurrent Sensor Using a Long-period Fiber Grating Inscribed on a High Birefringent Fiber (복굴절이 큰 광섬유에 제작된 장주기 광섬유 격자를 이용한 광섬유 전류 센서)

  • Lee, Yong-Wook
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.10
    • /
    • pp.1823-1825
    • /
    • 2007
  • Based on Faraday effect, the variation of current flowing through the conductor can be encoded as that of azimuth angle of light polarization propagating through the fiber coil wound onto the conductor. The amount of current can be obtained by measuring the variation of the light intensity transformed from that of the azimuth angle through a polarization analyzer. In this paper we propose a fiber-optic current sensor system that employs a fiber polarization analyzer as a sensor interrogation device. The fiber polarization analyzer was prepared by inscribing a long-period fiber grating on a high birefringent fiber. At the fixed wavelength of 1522.5 nm, the fabricated fiber device has the polarization extinction ratio of more than 25 dB. The measurement of large current up to 600 Arms was accomplished based on a simple fiber interrogation device and the measurement output of the sensor system showed a good linearity.