| 摘要: |
| 发电机定子绕组单相接地故障定位能扩展目前定子接地保护的功能，为快速检修故障提供依据。分析了大型汽轮发电机的电动势分布特征，推导了定子绕组电势与故障位置的关系，给出了新的定子绕组电势表达式。分析了定子绕组单相接地故障时零序电压、三相电压的幅值变化特征，推导了三相电压幅值变化与故障位置和接地电阻的关系。在此基础上，提出了一种综合利用零序电压和三相电压幅值特征的定子绕组单相接地故障定位新原理。理论分析和仿真计算表明:应用本方法能可靠识别故障位置，且该方法不受中性点接地方式的影响。该方案仅需要零序电压和机端三相电压，简单易行，不需增加额外设备，适用于高阻接地故障，仿真数据验证了算法的可行性。 |
| 关键词: 汽轮发电机 定子单相接地 零序电压 三相电压 定位 |
| DOI：10.7667/PSPC161504 |
| 投稿时间：2016-09-12修订日期：2016-11-01 |
| 基金项目:中央高校基本科研业务费专项资金资助(2016MS87) |
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| A new fault location method for stator single-phase ground fault in large turbine generator |
| HUANG Shaofeng,JIA Wenchao |
| (State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University, Baoding 071003, China) |
| Abstract: |
| Fault location for stator single-phase ground fault can extend the function of stator ground fault protection, providing a reference for fast detecting the fault. The paper analyses the potential characteristics of the large turbine generator, deduces the relation between the stator winding potential fault position, and gives a new formula of winding potential. The characteristics of zero sequence voltage and three phase voltage are analyzed when stator single-phase ground fault is occurring, and the relation between three-phase voltage amplitude and fault position & grounding resistance is deduced. Therefore, a new fault location principle based on the amplitude of zero sequence voltage and three-phase voltage is proposed. The theoretical analysis and simulation show that this method can detect the fault location reliably. In addition, it is immune no matter which neutral grounding mode is used. The fault location scheme only uses zero sequence voltage and three phase voltage, is very simple, don’t need additional equipment, and can be used to detect high impedance grounding fault. The simulation shows that it is feasible. This work is supported by Fundamental Research Funds for the Central Universities (No. 2016MS87). |
| Key words: turbine generator stator single-phase ground fault zero sequence voltage phase three-phase voltage fault location |
