CAJ | 학술논문

针对传统金属探测方法的缺点提出了基于跨导测量的金属探测新方法.通过检测发射线圈电流和平衡线圈的差分电压,将发射线圈电流信号与差分电压信号相乘,经低通滤波器滤波,得到跨有功功率.将跨有功功率值除以发射线圈电流有效值的平方,得到跨阻抗实部.通过检测跨阻抗实部或跨有功功率的过零点来探测金属,消除了平衡线圈一致性及其安装对称度对金属探测灵敏度的影响.实验结果表明所提出的方法能够显著提高金属探测的灵敏度.
침대전통금속탐측방법적결점제출료기우과도측량적금속탐측신방법.통과검측발사선권전류화평형선권적차분전압,장발사선권전류신호여차분전압신호상승,경저통려파기려파,득도과유공공솔.장과유공공솔치제이발사선권전류유효치적평방,득도과조항실부.통과검측과조항실부혹과유공공솔적과영점래탐측금속,소제료평형선권일치성급기안장대칭도대금속탐측령민도적영향.실험결과표명소제출적방법능구현저제고금속탐측적령민도.
@@@@In order to overcome the shortcomings of the traditional metal detection methods, the paper proposes a new method based on trans-conductance measurement is proposed. Two signals of the current across the transmitting coil and the differential voltage of the balance coils are detected respectively. A low-pass filter is designed for the product of these two signals to output the trans-active power, which is then divided by the squared value of the RMS of the transmitting coil current to give out the real part of the trans-impedance. The zero-crossing point of the real part of the trans-impedance or the trans-active power is used for detecting metal. In this way the consequence of the inconsistency of the balance coils and the un-symmetry in installing the coils to the metal detection sensitivity can be eliminated theoretically. The experiments prove that the sensitivity of metal detection is significantly improved.