基于HHT的高压直流输电故障测距算法的研究与仿真

本文介绍了用希尔伯特黄变换(HHT)对直流输电线路进行故障测距的方法。首先对测得的故障电流行波信号进行经验模态分解(EMD)得到一系列对应固有模态函数(IMF),对IMF进行希尔伯特(Hilbert)变换得到其时频图。根据时频图中的频率突变点得出故障行波到达两侧测量点的时间,并且根据其对应时刻的瞬时频率和具体线路的参数计算出其波速度。用改进的双端测距理论对直流线路进行测距。并对测得误差总体趋势和误差因子进行详细分析。相关仿真分析用EMTDC环境进行,仿真结果证实了所提方法的有效性。

Research and Simulation of fault location algorithm for HVDC transmission based on HHT

In this paper, a method of fault location for DC transmission lines by Hilbert Huang transform (HHT) is introduced. Firstly, a series of intrinsic mode functions (IMF) are obtained by the empirical mode decomposition (EMD) of the measured fault current traveling wave signals, and then the IMF (Hilbert) transform is used to obtain the time-frequency map. According to the frequency abrupt change point in time frequency chart, the time of fault traveling wave arriving at two measuring points is obtained. Distance measurement of DC line by improved double terminal ranging theory. The overall error and the error factor of the measurement error are analyzed in detail. The simulation results show that the proposed method is effective in EMTDC environment.