摘要
在实际社会生活中,金属检测广泛应用于众多领域,诸如食品、纺织、医疗等。但是对于含水含盐的被测物质,由于含有各种导电离子,离子在液体中运动便形成导体,致使对金属检测的灵敏度有较大的影响。为提高含水含盐被测物质中的金属探测灵敏度,基于FPGA平衡式双线圈金属探测系统研究了各种因素对金属探测灵敏度的影响。根据电涡流传感器原理,采用平衡式双线圈金属探测方法,通过数字锁相放大的信号处理方法,得到了与外部金属造成磁场强度变化成比例关系的输出信号,通过改变各影响因素,得到对应的输出信号与影响因素的关系,使得金属探测系统的灵敏度得到较大的提高。
In actual social life,metal detection is widely used in many fields,such as food,textile,medical and so on.However,for a water-containing salt-containing substance to be tested,since it contains various conductive ions,ions move in the liquid to form a conductor,which has a large influence on the sensitivity of metal detection.In order to improve the sensitivity of metal detection in water-containing salt-containing materials,this paper studies the influence of various factors on metal detection sensitivity based on FPGA balanced double-coil metal detection system.According to the principle of eddy current sensor,the balanced double-coil metal detection method is used to obtain the output signal proportional to the change of the magnetic field strength caused by the external metal through the digital phaselocked amplification signal processing method.By changing the influencing factors,the corresponding response is obtained.The relationship between the output signal and the influencing factors makes the sensitivity of the metal detection system greatly improved.
作者
张志飞
李丕丁
Zhang Zhifei;Li Piding(School of Medical Devices and Food Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)
出处
《电子测量技术》
2019年第17期48-53,共6页
Electronic Measurement Technology
