硬标签插磁调频装置控制系统设计与试验

针对目前无源电子硬标签生产过程,传统硬标签谐振频率检测技术用于插磁调频控制存在的不足,设计用于插磁调频装置的控制系统。提出了基于电容补偿原理的单线圈敏感硬标签谐振频率传感技术,建模仿真分析基于此技术的信号幅值比和相位差变化特性,发现相位差值和极性都存在反转特性;以此为基础设计以MSP430F149单片机为控制中心,控制产生固定频率信号源,相位检测和相位极性判别电路;以相位变化为控制系统提供反馈信号,采用相位差值反转特性实现下压高低速切换,相位极性反转特性完成下压的控制决策,有效给出了一种不需扫频、不受互感系数时变特性影响的压磁调频控制系统。以生产58KHz“中榔头”硬标签进行测试,数据分析表明,此套控制系统高速运行在20mm/s,低速为5mm/s时,硬标签谐振频率控制误差在±75Hz内,方差为0.0006~0.0008KHz,运行稳定。

Design and test of an electronic control system for adjusting hard label resonant frequency device

In view of the current passive electronic hard label production process,the traditional hard label resonance frequency detection technology is not enough for the insert magnetic rod to adjust frequency control device.The resonant frequency sensing technology of single coil sensitive hard tag based on capacitance compensation principle is proposed.Modeling and simulation analysis of signal amplitude ratio and phase difference variation characteristics based on this technology found that both phase difference and polarity have inversion characteristics.Based on this, the circuit is designed with MSP430F149 single chip microcomputer as control center, fixed frequency signal source, phase detection and phase polarity discrimination.The phase change is used to provide feedback signal for the control system, and the phase difference reversal characteristic is used to realize high and low speed switching, and the phase polarity reversal characteristic is used to complete the control decision of pressing down.This is a kind of frequency modulation control system of inserted magnetic bar, which does not need frequency sweeping and is not affected by the time-varying characteristics of mutual inductance.The production of 58KHz "medium hammer" hard tags was tested, data analysis showed that when the control system runs at a high speed of 20mm/s and a low speed of 5mm/s, the control error of hard label resonance frequency is within±50Hz and the variance is 0.0006~0.0008, and the operation is stable.