基于Lax差分格式的电力电缆故障测距仿真研究  

Simulation Study on Power Cable Fault Location Based on Lax Difference Scheme

作　　者：马贵东[1] 王红艳[1] 朱建忠 张鹏[1] 吴恒[1] 

机构地区：[1]南京工程学院,江苏南京211167

出　　处：《电气自动化》2017年第6期102-105,111,共5页Electrical Automation

摘　　要：为了解决电缆故障测距问题,运用偏微分方程的数值解法来进行时域分析,利用电缆的传输线模型,结合有限时域差分法对偏微分方程组进行离散,提出了一种基于Lax的差分格式。根据电流、电压在电缆线路的首端和末端的关系,确定了电缆的边界条件。另外,分析了电缆故障点的条件,模拟了电缆故障,并建立了低压脉冲法和脉冲电流法测距模型,利用MATLAB编程得到不同故障时的波形,分析计算得到故障距离,验证了差分格式的可行性,与其他差分格式相比,Lax的差分格式消除了因空间坐标离散导致的寄生震荡,得到的波形更加理想圆滑,对时间步数区分更加细致,在选取两波形点进行时间差计算时更加准确,从而得到故障点距离的精确度更高。To solve the problem of cable fault location,this paper introduces a numerical solution of partial differential equation for time domain analysis,and uses the transmission line model of the cable and finite difference time domain( FDTD) to disperse the partial differential equation. Here,we propose a Lax-based difference scheme. According to the relationship between current and voltage at the head end and tail end of the cable line,we can determine the boundary conditions of the cable. Furthermore,this paper analyzes the conditions of the cable fault point,simulates the cable fault,and establishes a location model for the low-voltage pulse method and pulse current method. Waveforms of different faults are obtained via MATALAB,fault location is obtained through analysis and computation,and the feasibility of the difference scheme is verified. Compared with other difference schemes,Lax difference scheme can eliminate spurious resonance caused by discrete space coordinates,give a more ideal,smooth waveform,make a more meticulous differentiation of the number of time steps,and conduct more accurate calculation of time difference between two selected waveform points,so that more accurate distance to fault can be obtained.

关 键 词：Lax差分格式 有限差分法 故障测距 电力电缆 

分 类 号：TM248[一般工业技术—材料科学与工程]