论文部分内容阅读
电力设备运行中的温升现象严重影响绝缘的使用寿命,因此高温下的空间电荷测量引起了许多学者的关注.但温度升高时,聚合物材料的声阻抗、Young模量、密度、声波在其中传播的速度、衰减特性均发生变化,因此无法准确测量出介质中的空间电荷特性.而对于温度梯度场下的绝缘介质(如电缆发热场)的空间电荷测量,温度的梯度分布对介质的声阻抗、弹性模量、密度、声速及声波衰减的影响将更为复杂.本文基于电声脉冲测量方法中声波的传播特性和温度对聚乙烯材料特性的影响,分析了温度梯度场对空间电荷测量结果的影响并进行了波形恢复。
Therefore, the space charge measurement under high temperature has attracted the attention of many scholars.But the temperature rise, the acoustic impedance, Young modulus, density, The velocity and attenuation characteristics of propagation are changed, so the space charge characteristics in the medium can not be accurately measured, while for the space charge measurement of the insulation medium in the temperature gradient field (such as the cable heating field), the gradient distribution of the temperature affects the medium The influence of acoustic impedance, elastic modulus, density, velocity of sound and acoustic attenuation will be more complex.Based on the propagation characteristics of acoustic wave and the influence of temperature on the properties of polyethylene material in electroacoustic pulse measurement, the effects of temperature gradient on space charge The effect of the measurement is measured and waveform recovery is performed.