中文摘要：

基于磁弹检测机理,提出一种磁弹拉力测量改进方法,即将谐波分析法应用于磁弹信号处理,通过统计信号频域各阶次谐波幅值,引入电气工程中表征波形相对正弦波畸变程度性能参数——总谐波畸变率来表征结构拉力。采用双套筒线圈式磁弹传感器在7芯钢绞线中获取磁弹检测试验信号,对比时域与谐波分析两种处理方法的特点,结果表明,谐波分析法处理过程更为简洁,所确立的标定方程的特性参数（线性拟合方程确定系数、斜率）随统计阶次增加而趋于稳定,且均优于时域处理结果,线性拟合方程确定系数可达0.996以上。同时,应用于高压输电导线的拉力测试,结果再次验证了总谐波畸变率与拉力间的良好线性关系。针对两种试验对象,当总谐波畸变率为1时,不同谐波统计阶次对应的标定方程对拉力的估算值间的相对误差均小于3%（其中7芯钢绞线最大为2.4%,高压输电线最大为2.9%）。该方法为磁弹拉力测量提供了一种新的表征及数据处理手段。

英文摘要：

An improved method for elastomagnetic（EM） effect-based tension measurement is presented using harmonic analysis technique（HAT）. The magnitudes of odd harmonics of EM signals are extracted to calculate the total harmonic distortion（THD）, which is commonly used in electrical engineering area to represent the extent of the distortion of sinusoidal signals. The value of THD is applied for tension characterization. The EM signals are acquired by a EM sensor which is made of two coaxial solenoid coils, and then are alternatively processed in time and frequency domain. The advantages of the two signal processing methods are compared to find that the HAT is much more succinct. The determined characteristic parameters of calibration equation, such as linear regression and slope, tend to be stable as the number of orders for statistics increases. Moreover, the obtained calibration equation has better parameters, for example, the linear regression is larger than 0.996. The mentioned techniques are then applied for measuring the tension of high voltage transmission line, the experimental results testify that there is a significant linear relationship between THD and the applied tension. When the value of THD is equal to 1, the relative errors of estimated forces, which are calculated from calibration equations corresponding to various statistical harmonic orders, are less than 3 % （a maximum of 2.4% for seven-wire steel strand and a maximum of 2.9% for high voltage transmission line）. This study provides a new characterization and data processing method for EM-based tension measurement technology.