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| 摘要: |
| 研究了小电流接地系统的特点,在此基础上分析了各种保护,讨论了存在的问题,提出利用附加低频信号技术进行小电流接地系统保护和故障选线的新理论。该理论的主要特点是采用低频信号,通常选用12.5Hz、14.5Hz等系列,其大小约为50Hz的1/N(N>1)。在此基础上进行了保护分析,建立了电路模型,分析了该理论的各相关参数的计算方法。同时阐述了该理论的优点:利用该理论不会改变系统的运行状态,同时也几乎不受实际负荷变化的影响。根据该方法的原理和特点,最后提出利用幅值法和相位比较法可以进行可靠选线。 |
| 关键词: 单相接地故障系统,相位比较法,小电流接地系统,注入信号 |
| DOI： |
| 分类号:TM711 |
| 基金项目: |
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| Single-phase-to-ground fault line selection based on additional low-frequency-signal injection |
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LI Jianmin
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| Abstract: |
| Based on the study of non - solidly earthed network and its various protections,the existing problems are analyzed and a concept of non - solidly earthed network protection and faulty line selection applying additional low frequency signal injection technique is proposed. The low frequency signals are usually 12.5 Hz,14.5 Hz,etc.,about 1 / N of 50 Hz(N > 1). The circuit model is built and the calculation of relevant parameters is analyzed. The application of this concept will not change system operational status and the actual load has nearly no influence on it. Based on this concept,the faulty line can be selected by the amplitude method and phase comparison method. |
| Key words: single - phase - to - ground fault,phase comparison method,non - solidly earthed network,signal injection |
