• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1992.11a
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• pp.114-117
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• 1992

This paper presents the design and calibration methods of self-integrated magnetic sensor. Also the distance response measurement of magnetic field produced a transient large current and the frequency response measurement are carried out As the integrating resistance increases. the sensitivity of the sensor is improved, but the decay time constant of response decreases, Also the experimental results are well agreed with the theoretical analysis of the equivalent circuit.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.4
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• pp.84-91
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• 2010

Owing to revolutionary developments in automobile technologies, a variety of advanced vehicles - hybrid vehicle, hydrogen fuel-cell vehicle, electric vehicle, etc. - emerges recently. The safety is getting more important for developing automobiles. The electro-magnetic compatibility has to be assured, since those advanced vehicles are equipped with various new electronic systems. Electro-magnetic compatibility tests, in general, consist of an EMI(electro-magnetic interference) test and an EMS (electro-magnetic susceptibility) test. We investigated the susceptibility test method suggested in KMVSS (Korean Motor Vehicle Safety Standard) as the EMS test method. A series of experiments results that the above test method should be partially revised to comply with a Korean governmental standard method. In this paper, the some directions of modifications are presented to enhance the quality of the above EMS test method.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.6
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• pp.1001-1009
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• 1994

The present paper deals with a new developed sensor for measuring the time-varying magnetic fields and describes the experimental results of trasient magnetic field that takes place during the operations of electric appliance. The operation principle of the self-integrating magnetic field sensor by using coaxial cable is analyzed and a calibration investigation is carried out. The frequency bandwidth of the magnetic field measurement system is from 40 Hz to about 300 kHz. The magnetic field induced by the starting and/or operation of electric appliance mainly includes the odd harmonics such as the third, the fifth and the seventh harmonics. The magnetic field intensity caused during the operation of ultrasonic washer is inversely proportional to distance, this correspodns to induction component. As a result, it was known that the odd harmonics of magnetic field in the desing of electromagnetic shield employed for protecting electronic circuit and control devices have to be considered.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.12
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• pp.1365-1372
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• 2012

This paper presents a methodology to accurately evaluate the spectral components of impulse signals which are delivered from an impulse generator through the measurement system. The complicated terms for uncertainty measurement of impulse spectrum amplitude and their analysis methods and experimental results are discussed. The expanded uncertainty of the impulse spectrum measurement is 0.015, which is believed to be the best domestic measurement capability and comparable to those of world class.

• Korean Journal of Remote Sensing
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• v.15 no.4
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• pp.297-305
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• 1999

Ocean Scanning Multispectral Imager (OSMI) is a payload on the KOMPSAT satellite to perform global ocean color monitoring for the study of biological oceanography. The instrument images the ocean surface using a wisk-broom motion with a swath width of 800km and a ground sample distance (GSD) of < 1km over the entire field of view (FOV). The instrument is designed to have an on-orbit operation duty cycle of 20% over the mission lifetime of 3 years with the functions of programmable gain/offset and on-board image data compression/storage. The instrument also performs sun and dark calibration for on-board instrument calibration. The OSMI instrument is a multi-spectral imager covering the spectral range from 400nm to 900nm using CCD Focal Plane Array (FPA). The ocean colors are monitored using 6 spectral channels that can be selected via ground commands. KOMPSAT satellite with OSMI was integrated and the satellite level environment tests including instrument aliveness/functional test, such as launch environment, on-orbit environment (Thermal/Vacuum) and EMI/EMC test were performed at KARl. Test results met the requirements and the OSMI data were collected and analyzed during each test phase. The instrument is launched on the KOMPSAT satellite on December 21,1999 and is scheduled to start collecting ocean color data in the early 2000 upon completion of on-orbit instrument checkout.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.9 no.2
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• pp.58-67
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• 1995

The paper describes the variation of magnetic fields caused by the operation of induction motors. The measuring system consists of the self-integrating magnetic field sensor, amplifier, and active integrator. From the calibration experiments, the frequency bandwidth of the magnetic field measuring system ranges from 20[Hz] to 300[kHz] and sensitivity is 0.234(mV/$\mu\textrm{T}$]. The magnetic fields generated under steady state and starting operations of duction motor are recorded by the proposed measuring system, and the fast Fourier transformation(FFT) of the measured data is performed to analyze the harmonic components. A single pulsed magnetic field is strongly caused by direct starting the induction motor, and its peak value is greater than 5 times as compared with the steady state value. The long transient duration and high intensity originates from the large inductance and dynamic characteristic of the induction motor, During the steady state operation of induction motor, subharmonics of magnetic field components, which depend on the pole number of induction motor, are observed. The lower order power-line harmonics can be inferred from the voltage flicker and current ripple which are derived from the torque fluctuation of induction motor. In the case of the induction motor drived by inverter, the harmonics of magnetic field are much more than those caused by direct starting method and are found generally to increase with decreasing the driving frequency.