| 引用本文: | 陈晓东,柳亦钢,李天云.利用二次小波变换区分变压器励磁涌流和短路电流的符号法[J].电力自动化设备,2006,(6):48-52 |
| .Sign identifying method to discriminate inrush current and fault current of transformer based on twice wavelet[J].Electric Power Automation Equipment,2006,(6):48-52 |
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| 摘要: |
| 通过选取合适的小波基函数,利用小波变换对采样得到的差流进行一次或二次小波变换,再提取小波变换系数的局部模极大值符号,利用定义的符号识别公式即可区分对称性涌流、非对称性涌流以及内部故障电流,还能鉴别出励磁涌流伴随内部故障情况以及电流互感器饱和采样得到的励磁涌流。Matlab仿真及动模实验校验表明,该方法简单有效,不受噪声干扰,易于在工程上实现。 |
| 关键词: 变压器差动保护,小波变换,模极大值,符号识别法 |
| DOI： |
| 分类号:TM771 |
| 基金项目: |
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| Sign identifying method to discriminate inrush current and fault current of transformer based on twice wavelet |
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CHEN Xiao-dong LIU Yi-gang LI Tian-yun
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| Abstract: |
| With selected appropriate wavelet fundamental functions,the sampled differential current is transformed once or twice,and with the extracted sign of the local modulus maximum of wavelet coefficients and the defined sign identification function,the symmetrical inrush,the asymmetrical inrush and the internal fault current are distinguished from each other,as well as the excitation inrush accompanying with the internal fault current or the current transformer saturation is distinguished. Simulations with Matlab and experiments prove that the method is simple,effective,free from noise and easy to be implemented. |
| Key words: transformer differential relay,wavelet transforms,modulus maximum,sign identifying method |
