| 引用本文: | 高淑萍,徐振曦,宋国兵,邵明星,姜元月.基于小波阈值去噪和CEEMD的混合三端直流输电线路故障测距[J].电力系统保护与控制,2022,50(3):29-40.[点击复制] |
| GAO Shuping,XU Zhenxi,SONG Guobing,SHAO Mingxing,JIANG Yuanyue.Fault location of hybrid three-terminal HVDC transmission lines based on wavelet threshold denoising and CEEMD[J].Power System Protection and Control,2022,50(3):29-40[点击复制] |
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| 摘要: |
| 针对行波法测距精度受波速、行波波头标定的精度以及噪声的影响，提出一种基于小波阈值去噪和CEEMD-HT结合的混合三端直流输电线路测距方法。首先利用小波阈值去噪对故障信号滤噪，然后对滤噪后的信号使用互补集合经验模态分解和希尔伯特变换标定初始波头的到达时间。再根据故障行波到达测量端时间比值识别故障支路。最后考虑到行波波速难以精确确定，基于已知线路长度和初始波头到达时间，提出一种不受波速影响的测距方法。仿真结果表明，所提方法能够有效标定波头，且测距结果不受波速、故障距离、故障类型、过渡电阻及噪声的影响。与利用波速计算的双端法、HHT及小波包测距算法相比，该方法的测距误差更小。 |
| 关键词: 混合三端直流输电系统 行波法 时频图 互补集合经验模态分解 三端故障测距 |
| DOI：DOI: 10.19783/j.cnki.pspc.210421 |
| 投稿时间：2021-04-15修订日期：2021-07-22 |
| 基金项目:国家自然科学基金面上项目资助(51777166)；国家自然科学基金联合基金重点支持项目资助(U1766209) |
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| Fault location of hybrid three-terminal HVDC transmission lines based on wavelet threshold denoising and CEEMD |
| GAO Shuping,XU Zhenxi,SONG Guobing,SHAO Mingxing,JIANG Yuanyue |
| (1. College of Electrical and Control Engineering, Xi'an University of Science and Technology, Xi'an 710600, China;
2. School of Electrical Engineering, Xi'an Jiaotong University, Xi'an 710049, China) |
| Abstract: |
| Considering the influence of wave speed, precision of traveling wave head calibration and noise on the location accuracy of the traveling wave method, a hybrid three-terminal HVDC transmission line location method based on wavelet threshold denoising and CEEMD-HT is proposed. First, the fault signal is denoised by wavelet threshold denoising, and then the arrival time of the initial wave head is calibrated by combining complementary ensemble empirical mode decomposition and a Hilbert transform (CEEMD-HT). Then the fault branch is identified according to the ratio of the time of the fault traveling wave to the measuring end. Finally, considering that the traveling wave velocity is difficult to determine accurately, based on the known line length and the initial arrival time of the wave head, a new location method independent of the wave velocity is proposed. The simulation results show that the proposed method can calibrate the wave head effectively, and the location results are not affected by wave velocity, fault distance, fault type, transition resistance and noise. The error of this method is smaller than the double end method, and the HHT and wavelet packet ranging algorithm.
This work is supported by the General Project of National Natural Science Foundation of China (No. 51777166). |
| Key words: hybrid three-terminal DC transmission system traveling wave method time-frequency diagram complementary ensemble empirical mode decomposition three-terminal fault location |
