| 引用本文: | 戴志辉,奚潇睿,李杭泽,等.基于波速度比例因子的混合多端直流输电线路故障测距方法[J].电力系统保护与控制,2025,53(9):141-153.[点击复制] |
| DAI Zhihui,XI Xiaorui,LI Hangze,et al.Fault location method for hybrid multi-terminal DC transmission lines based on wave velocity scale factor[J].Power System Protection and Control,2025,53(9):141-153[点击复制] |
|
| 摘要: |
| 针对现有行波测距方法受波速度影响大、抗同步误差能力弱、反射波头标定困难、在多端直流输电系统中适应性差等问题，提出一种基于波速度比例因子的混合多端直流输电线路故障测距方法。首先分析波速度的沿线变化特性，并充分利用同一测点处不同模量波速度变化趋势相同而变化快慢不同的特点，定义能够间接反映故障距离的波速度比例因子。其次分别采用插值拟合及定量推导的方法求解该比例因子随故障距离变化的拟合曲线与计算曲线，利用其单调性差异提出联立曲线求解故障距离的测距方案。为准确标定故障行波，提出一种结合鲁棒局部均值分解与多分辨奇异值分解的波头标定方法，并利用标定结果设计基于时差特性的故障支路识别判据。最后经仿真验证表明，所提方法测距精度较高，计算量小，不受同步误差影响，且具有较强的耐过渡电阻(500 Ω)和抗噪声(20 dB)能力，在不同线路中的适用性强。 |
| 关键词: 混合多端直流输电系统 故障测距 波速度变化特性 行波波头标定 插值拟合 |
| DOI：10.19783/j.cnki.pspc.240404 |
| 投稿时间：2024-04-06修订日期：2024-08-16 |
| 基金项目:河北省自然科学基金项目资助(E2024502043) |
|
| Fault location method for hybrid multi-terminal DC transmission lines based on wave velocity scale factor |
| DAI Zhihui,XI Xiaorui,LI Hangze,NIU Baoyi |
| (State Key Laboratory of Alternate Electrical Power System with Renewable Energy Resources,
North China Electric Power University, Baoding 071000, China) |
| Abstract: |
| Aiming at the issues of existing traveling wave location methods, such as high sensitivity to wave velocity, poor resistance to synchronization errors, difficulty in calibrating the wave head of reflected waves, and poor adaptability in multi-terminal HVDC systems, a fault location method for hybrid multi-terminal HVDC lines based on the wave velocity scale factor is proposed. First, the variation characteristics of wave velocity along the line are analyzed. By leveraging the fact that the wave velocities of different modulus at the same measuring point exhibit the same trend but different rates of wave velocity variation, a wave velocity scale factor which can indirectly reflect the fault distance is defined. Second, the fitting curve and calculation curve between the scale factor and the fault distance are solved by interpolation fitting and quantitative derivation, respectively. Based on the monotone difference of the above curves, a fault location scheme is proposed to solve the fault distance with parallel curves. To accurately identify the fault traveling wave head, a wave head calibration method combining robust local mean decomposition and multi-resolution singular value decomposition is proposed. Based on the calibration results, a time-delay-based criterion is designed for identifying the fault branch. Finally, simulation results show that the proposed location method has high accuracy, low computational complexity, immunity to synchronization error, strong resistance to transition resistance (500 Ω) and noise (20 dB), and excellent adaptability across different transmission lines. |
| Key words: hybrid multi-terminal high voltage direct current system fault location wave velocity variation characteristics traveling wave head calibration interpolation fitting |
