| 引用本文: | 见文号,高湛军,陶政臣.基于信号拟合和图像对比的有源配电网故障时刻检测方法[J].电力系统保护与控制,2024,52(21):161-169.[点击复制] |
| JIAN Wenhao,GAO Zhanjun,TAO Zhengchen.Fault time detection method of an active distribution network based onsignal fitting and image comparison[J].Power System Protection and Control,2024,52(21):161-169[点击复制] |
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| 摘要: |
| 为了解决传统故障时刻检测方法较依赖采样频率且易受谐波和衰减振荡影响的问题，提出了一种信号拟合和图像对比相结合的故障时刻检测方法。首先，该方法将衰减因子引入傅里叶级数拟合模型，可精确拟合并扩展信号中的谐波和衰减振荡分量。然后，利用差异哈希对扩展信号和原始故障信号进行分段对比，使用中值滤波去除由拟合误差带来的零散像素点。最后，逐列检测故障时刻。仿真表明，该方法将检测误差控制在像素级，对采样频率较低或具有谐波和衰减振荡的信号也可准确地检测故障时刻，适用多种复杂的故障场景。 |
| 关键词: 数据自同步 故障时刻检测 改进傅里叶拟合模型 差异哈希 |
| DOI：10.19783/j.cnki.pspc.240433 |
| 投稿时间：2024-04-12修订日期：2024-06-27 |
| 基金项目:国家电网有限公司总部管理科技项目资助(52060019001H) |
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| Fault time detection method of an active distribution network based onsignal fitting and image comparison |
| JIAN Wenhao,GAO Zhanjun,TAO Zhengchen |
| (Key Laboratory of Power Grid Intelligent Dispatch and Control of Ministry of Education
(Shandong University), Jinan 250061, China) |
| Abstract: |
| The traditional fault time detection method is dependent on the sampling frequency and is easily affected by harmonics and attenuation oscillation. Thus a fault time detection method combining signal fitting and image comparison is proposed. First, an attenuation factor is introduced into the Fourier series fitting model. This can accurately fit the harmonics and attenuation oscillation components in the extended signal. Then, the differential Hash is used to compare the extended signal and the original fault signal in segments, and a median filter is used to remove the scattered pixels caused by the fitting error. Finally, the fault time is detected column by column. The simulation results show that the method can control the detection error at the pixel level, and can accurately detect the fault time at a low sampling frequency or when there are signals with harmonics and damped oscillations. The method is suitable for a variety of complex fault scenarios. |
| Key words: data self-synchronization fault time detection improved Fourier fitting model difference Hash |
