中频强磁场测量仪的误差分析与优化设计

Error Analysis and Optimization Design of Intermediate Frequency Magnetic Measuring Instrument

为了提高已有中频强磁场测量仪的精度、实时性和抗干扰能力,通过电路和信号分析,采用低输入失调电压、低噪声的运放构建输入信号调理电路,减少由电路静态输出电压和导通电阻引起的测量误差,对调理后信号直接ADC采样获取信号峰值,减少由整流滤波和数据拟合引起测量误差及实时性和一致性问题。对经过优化后测量仪进行测试,实验结果表明测量误差小于3%,小信号准确检测范围扩展30%,一致性误差小于1%,同时测量的实时性也得到提高。

To improve the existed measuring accuracy, real-time and anti-jamming capability of medium-frequency strong magnetic field measurement instrument,the low input offset voltage,low noise op-amp was used to reduce the measuring error of the signal recuperation electric circuit, which causes by the electric circuit static output voltage and the breakover resistance. The ADC sampled signal got peak value to reduce the measurement error,real-time and consistency issues caused by the rectifier filtering and data fitting. Testing the meas uring instrument optimized,the experiment results show that measuring error is smaller than 3 %, small signal accurate detection range ex tended 30%, consistency of measurement error is less than 1%, the real-time nature also has improved.