FeGa/PZT圆柱体磁电复合材料在8/20μs雷电激励下磁电响应仿真分析

Simulation analysis of magnetoelectric response of FeGa/PZT cylindricalmagnetoelectric composite under 8/20μs lightning current

目前,雷击故障以成为线路的主要故障之一。8/20μs雷电流是电力系统实验中典型的冲击电流波形。借助有限元仿真分析软件COMSOL,分析FeGa/PZT圆柱体磁电复合材料在8/20μs雷电激励下磁电响应,为磁电复合材料在雷电测量领域提供理论分析基础。仿真中,采用二维轴对称结构建立了FeGa/PZT圆柱体磁电复合材料的模型;首先,对复合材料在正弦激励下的磁电效应进行了仿真,得知结构主振模态为一阶纵波振动,频率为100.36 kHz。其次,采用双指数函数模型模拟8/20μs雷电流瞬态激励电流,对结构瞬态磁电响应进行了仿真分析。结果表明,FeGa/PZT圆柱体磁电复合材料输出电压可以有效跟随8/20μs雷电流变化过程,但以频率100.36 kHz进行阻尼振荡;在峰值为0.5 A~10 kA的8/20μs雷电流测量范围内,FeGa/PZT磁电复合材料对8/20μs雷电流幅值测量灵敏度达到1.8 mV/A,线性度达到98.55%。以上结果证明,FeGa/PZT磁电复合材料在雷电流测量领域有良好的应用前景。

At present,lightning strike fault has become one of the main faults of power lines.8/20μs lightning current is a typical impulse current waveform in power system experiment.In this paper,we analyze the magnetoelectric response of FeGa/PZT cylinder composite under 8/20μs lightning current by using the finite element simulation software COMSOL.This work provides a theoretical analysis basis for the application of magnetoelectric composites in the field of lightning measurement.In the simulation,the model of FeGa/PZT cylindrical magnetoelectric composite is established by using two-dimensional axisymmetric structure.Firstly,the magnetoelectric effect of composites under sinusoidal excitation is simulated.It is found that the main vibration mode of the structure is first-order longitudinal wave vibration,and the frequency is 100.36 kHz.Secondly,the double exponential function model is used to simulate 8/20μs lightning current.And the transient magnetoelectric response of the FeGa/PZT cylinder composite is simulated in detail.The results show that the output voltage of FeGa/PZT composite can effectively follow 8/20μs lightning current variation.However,the damped oscillation is carried out at the frequency of 100.36 kHz.In the measurement range of 0.5 A-10 kA,the sensitivity of FeGa/PZT magnetoelectric composite to 8/20μs lightning current amplitude reaches 1.8 mV/A,and the linearity is 98.55%.The above results show that FeGa/PZT composite has a good application prospect in the field of lightning current measurement.