引用本文: | 吴梓亮,曾耿晖,李一泉,等.基于双门槛值的变压器Hausdorff距离快速保护新判据[J].电力系统保护与控制,2019,47(18):128-135.[点击复制] |
WU Ziliang,ZENG Genghui,LI Yiquan,et al.A novel criterion for fast protection of transformer based on Hausdorff distance and double threshold (1. Electric Power Dispatching Control Center of Guangdong Power Grid Co., Ltd., Guangzhou 510600, China; 2. Key[J].Power System Protection and Control,2019,47(18):128-135[点击复制] |
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摘要: |
传统变压器差动保护一般采用傅里叶变换提取变压器两侧差流的基波分量,无法识别变压器内部轻微匝间故障。受数据窗长度的影响,保护通常至少需要半个周波才能出口动作,且在外部故障导致电流互感器(CT)饱和时可能出现保护误动。为解决上述问题,提出了一种基于Hausdorff距离的变压器保护新判据,通过对比变压器高低压侧电流波形的相似度,以达到快速识别区内外故障的效果。理论分析表明该判据的数据窗长度可以任意选取,有利于提升保护动作速度,同时双整定门槛值既保证了严重区内故障情况下保护能够快速跳闸又保证了区外故障伴随CT饱和工况下保护准确不动作。最后基于PSCAD/EMTDC对所提判据的有效性进行仿真验证。结果表明,所提判据能快速动作,动作时间可低至5.5 ms,即使发生0.5%的轻微匝间故障,保护也能在故障后一周波内跳闸,且具有较强的抗CT饱和性能。 |
关键词: 变压器 波形相似识别 Hausdorff距离 匝间故障 CT饱和 双整定门槛 |
DOI:10.19783/j.cnki.pspc.190327 |
投稿时间:2019-03-25修订日期:2019-05-08 |
基金项目:国家自然科学基金面上项目资助(51677108);广东电网有限责任公司科技项目资助(GDKJQQ20161176) |
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A novel criterion for fast protection of transformer based on Hausdorff distance and double threshold (1. Electric Power Dispatching Control Center of Guangdong Power Grid Co., Ltd., Guangzhou 510600, China; 2. Key |
WU Ziliang,ZENG Genghui,LI Yiquan,WANG Feng,TU Qingrui,YANG Yun,ZHAO Qingchun |
(Electric Power Dispatching Control Center of Guangdong Power Grid Co., Ltd., Guangzhou 510600, China ;Key Laboratory for Protective Relaying Real Time Digital Simulation of Guangdong Power Grid Co., Ltd., Guangzhou 510600, China;Nari-relay Engineering and Technique Co., Ltd., Nanjing 211102, China) |
Abstract: |
Traditional transformer differential protection generally uses Fourier transform to calculate fundamental component. It cannot identify low percentage interturn faults inside the transformer. And the operating time is usually more than half a cycle affected by the length of data window. What’s more, the protection may operate by mistake when there is an external fault accompanied by CT saturation. In order to solve the above problems, a new criterion for transformer protection based on Hausdorff distance is proposed in this paper. The similarity of current waveforms on both sides of the transformer is compared to distinguish the internal faults from external ones quickly. Theoretical analysis shows that the length of the data window can be selected arbitrarily in new criteria, which is conducive to improving the protection action speed. At the same time, the double setting threshold ensures not only the rapid tripping speed in the case of severe faults, but also the correct operation of protection when an external fault occurs accompanied with CT saturation. Finally, the validity of criteria is verified based on PSCAD/EMTDC. The simulation results show that the criteria can operate quickly and the action time can be as short as 5.5 ms. And the protection can operate in one cycle after fault even if the percentage of interturn fault is only 0.5%. Besides, it has strong anti-CT saturation performance. This work is supported by National Natural Science Foundation of China (No. 51677108) and Science and Technology Project of Guangdong Power Grid Co., Ltd. (No. GDKJQQ20161176). |
Key words: transformer similarity recognition for waveform Hausdorff distance interturn fault CT saturation double setting threshold |