摘要
笔者利用投影变换、微分函数的代数逼近建立频率相关参数的离散时间数字方程,将其进行z变换,得到z域内的行波传输方程。利用Poisson求和公式,得到传播函数和波阻抗的递归离散序列,考虑传播函数的频率响应相当于IIR低通滤波器,采用Prony算法将其参数拟合为零极点的形式,减少离散序列的个数,最终将行波传播计算转化为系数很少的递归计算。在适合现有保护装置能够实现的较低采样频率下,基于频率相关模型的基础上实现利用首端行波计算对侧行波的快速算法。通过PSCAD仿真表明,该算法具有较高的准确性和精确性,取得了很好地效果。
A discrete-time numerical equation of frequency-dependent parameters is established by adopting projection transform and algebraic approximation of differential function. And z transform is used to convert the numerical equation into a traveling wave propagation equation in z domain. The recursive discrete sequences of propagation function and wave impedance are obtained through Poisson summation formula. Considering that the propagation function＇s frequency response is equivalent to a IIR low-pass filter,the parameters are fitted as the form of a zero pole via Prony algorithm to decrease the number of discrete sequences,and eventually to convert the calculation of traveling wave propagation into the recursive calculation with less coefficients. In the condition of lower sampling frequency suitable for the existing protection devices, the fast algorithm for calculating contralateral traveling wave by making use of head traveling wave is realized on the basis of the frequency-dependent model. Simulation with PSCAD show that the proposed algorithm is more accurate and precise.
出处
《高压电器》
CAS
CSCD
北大核心
2014年第9期23-28,34,共7页
High Voltage Apparatus
基金
山东省高等学校科技计划项目(J14LN27)
山东理工大学科技计划资助项目(103121和103233)
博士科研启动基金(411019)~~
关键词
传播函数
频率相关模型
行波传播
propagation function
frequency-dependent model
traveling wave propagation
