루우프형 센서를 이용한 자장측정계 = Magnetic Field Measuring System by using Loop-type Sensor

다국어 초록 (Multilingual Abstract)

This paper deals with the active magnetic field measuring system which can measure the time-varying magnetic fields generated by power installations and lightning discharges. The magnetic field measuring system consists of the loop-type magnetic field sensor and the active integrator operated by a differential amplifier. The theoretical principle and design rule of the time-varying magnetic field measuring device and the calibration apparatus are introduced. From the calibration experiments, the frequency bandwidth of the full measuring system ranges from 270 Hz to about 2.3 MHz and the response sensitivity for magentic field strength is 128 $mV/{\mu}T$, respectively, and the calculated B-field values in the center of the loop-type sensor versus the the applied current made with a region of ${\pm}3\;%$error. The actual survey experiments by using lightning impulse current and oscillating impulse current were performed, the results of comparision between the input current waveforms and the magnetic field waveforms are a good agreement with each others and their deviations are less than 0.5 %.