摘要
分析了线路参数的频变特性,计算得出行波衰减系数和波速度随频率的变化规律,当行波传输距离增加时,行波波头会发生畸变,行波信号的奇异性会降低,给精确确定波速度和行波到达时间带来了困难,从而降低了行波测距精度。在此基础之上,从行波的传输理论入手提出一种基于线路参数频变特性的小波域行波信号奇异性增强方法,利用卡森公式求出一定频带内行波信号的传播系数,在频域计算得到行波校正函数,在小波域利用快速傅里叶变换对畸变后的行波波头进行补偿,消除或减弱了行波传输中的色散效应,增强了行波信号的奇异性,提高了行波故障测距精度。仿真实验表明,该方法可使现有行波测距法的测距精度得到有效提高。
The frequency characteristic of line parameter was analyzed in the paper,and the change law of attenuation coefficient and velocity with frequency were obtained;when the transmission distance increased,the wave front of traveling-wave would be distorted,and its singularity would decrease,which made it difficult to accurately determine the velocity and arrival time of traveling-wave,the accuracy of fault location would be reduced.Based on the propagation theory of traveling-wave,the paper proposed a singularity enhancement method in wavelet domain with considering the frequency characteristic of line parameter.The propagation coefficients of traveling-wave within a certain band were calculated by carson equation,the correction function was obtained in frequency domain,and it was used to compensate the distorted wave front of traveling-wave in wavelet domain by fast fourier transform.Thus,the dispersion effect of traveling-wave was reduced or eliminated,the singularity of traveling-wave was enhanced and the accuracy of fault location was improved.Simulation experiments illustrate that the proposed method can effectively improve the accuracy of current traveling-wave-based fault location methods.
出处
《电工技术学报》
EI
CSCD
北大核心
2017年第15期153-160,共8页
Transactions of China Electrotechnical Society
基金
河北省自然科学基金(E2013502267)
中央高校基奉科研业务费专项资金(13MS68
2017MS113)资助项目
关键词
行波
色散
故障测距
双端法
Traveling-wave
dispersion effect
fault location
double-ended method
