摘要
大地电磁测深需要较宽频率范围的感应式磁传感器来探测大深度范围,针对电补偿无法解决感应线圈在谐振点处有相位突变以致频带受限的问题,提出了磁反馈方法。磁反馈的原理是将感应信号放大后转换成电流量,电流通过反馈线圈产生磁场对被测磁场形成磁通负反馈。通过仿真及实验证明了该方法能够解决感应线圈在谐振点处有相位突变的问题,并且使传感器在低频率段有平坦的灵敏度曲线,较大地拓宽了频带。标定的结果表明传感器频率范围是0.001Hz～60kHz,在频率小于1Hz的范围内灵敏度为0.24V/(nT.Hz),频率高于1Hz时,为0.69mV/(nT.Hz)(@1kHz),能够满足大深度范围探测的需要。
Magneto-Telluric detection requires a wide frequency range magnetic sensor to detect a large depth range. Because electric compensation can not solve the phase mutation problem at the resonance frequency of the coil, which results in limited bandwidth, so a flux feedback method is brought forward. The principle of flux feedback is that the induced voltage is converted into electrical current after amplification, the current produces magnetic field through a feedback coil, which forms negative flux feedback to the measured magnetic field. Simulation and experiment show that the flux feedback method can solve phase mutation at resonance frequency. The sensor has a flat sensitivity curve at low frequency band and broadens the frequency band greatly. Calibration results indicate that the frequency range of the sensor is 0.001 Hz～60 kHz and the sensitivity is 0.24 V/（nT·Hz） below 1 Hz, and 0.69 mV/（nT·Hz） at 1 kHz, which is able to meet the requirements of large depth range detection.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2010年第11期2461-2466,共6页
Chinese Journal of Scientific Instrument
基金
国家自然科学基金(40904053)资助项目
关键词
磁反馈
感应式
互感
耦合
magnetic flux feedback
induction
mutual inductance
coupling
