磁悬浮振动传感系统及误差分析

Vibration Sensing System Based on Magnetic Levitation and Error Analysis

摘要:

利用磁悬浮技术设计一款惯性振动传感器,对传感系统进行受力分析,得出系统二阶运动方程;同时进行磁路分析得到系统刚度表达式,涡流分析得到系统的阻尼表达式,进而计算出传感系统的各部分参数,其刚度值为140 N/m,固有频率为11.2 Hz,阻尼为2.56 N·s/m;通过分析传感系统的温度误差与非线性误差,提出误差补偿方法:对温度误差进行热磁分流补偿,对非线性误差进行线圈补偿;标定得出传感器的灵敏度高达220 V·s·m-1;使用该传感器对爆炸冲击信号进行测量,实验结果表明该传感器能较好地描述爆炸振动信号;并且该传感器有灵敏度高、结构简单、防电磁干扰等优点。

Abstract:

Using magnetic levitation technology to design a inertia vibration sensor, by analyzing sensing system’s force, the second order equations in dynamics of sensor system can be derived. Sensing system’s stiffness expression is derived by magnetic circuit analysis, and its damping expression is derived by eddy current analysis, then parameters of sensor are calculated, stiffness value is 140 N/m, natural frequency is 11.2 Hz, damping value is 2.56 N·s/m. By analysis of the temperature error and nonlinear error of the sensor system, error compensation method is put forward:thermal magnetic shunt can compensate the temperature error, compensating coil can compensate the nonlinear error. The sensitivity verified by experimental calibration method is 213 V·s·m-1. Explosion signals are collected by magnetic levitation vibration sensor, the experimental results show that the sensor can be better used in collecting explosion vibration data. The sensor has advantages of high sensitivity, simple structure and preventing electromagnetic interference ability.