架空-电缆混合线路接地故障距离保护整定研究
A Study on Setting of Ground-Fault Distance Protection for the Overhead-Cable Hybrid Line
伍美娟 1陈阳 2梁振锋 1王晓卫 1宋国兵3
作者信息
- 1. 西安理工大学电气工程学院,陕西西安 710054
- 2. 国网陕西省电力公司西安供电公司,陕西西安 710048
- 3. 西安交通大学电气工程学院,陕西西安 710049
- 折叠
摘要
针对架空线与电缆的线路参数不均一,提出了架空-电缆混合线路接地距离保护的整定优化方法.分析了零序电流补偿系数对测量阻抗的影响,两侧保护分别采用从母线起混合线路全长 70%的正序阻抗和零序阻抗来计算零序电流补偿系数;分析了故障处于不同位置时,架空线侧和电缆侧的保护所采集的故障相电压波形特征,发现电缆侧保护所采集的故障相电压含有较大幅值的非整次谐波,故架空线侧保护采用从母线起线路全长 70%的正序阻抗作为整定阻抗,而电缆侧保护采用整条线路正序阻抗的 70%作为整定阻抗.利用PSCAD建立了架空-电缆混合线路模型并进行故障仿真,结果表明,该方法可有效提高架空-电缆混合线路接地距离保护Ⅰ段的灵敏性.
Abstract
To address the uneven parameters of overhead lines and cables in the overhead and cable hybrid line,an optimal setting method for grounding distance protection of the hybrid line is proposed.First,the influence of the zero-sequence current compensation coefficient on the measured impedance is analyzed.The positive sequence impedance and zero-sequence impedance of 70%of the total length of the hybrid line from the bus are used to calculate the zero-sequence current compensation coefficient.Second,the waveform characteristics of the fault phase voltage collected by overhead line and cable side protection when the fault occurs in different positions are analyzed.It is found that the fault phase voltage collected by the cable side protection contains a large amplitude of non integral harmonics.Therefore,70%of the total length of the line from the bus is used as the setting impedance for the overhead line side protection,70%of the positive sequence impedance of the whole line is used as the setting impedance for the cable side protection.A simulation model for the hybrid line fault is built by PSCAD.The simulation results show that the method proposed in this paper can effectively improve the sensitivity and reliability of grounding distance protection of Section I.
关键词
架空-电缆混合线路/距离保护/零序电流补偿系数/整定阻抗/灵敏性/可靠性Key words
overhead-cable hybrid line/distance protection/zero-sequence current compensation coefficient/setting impedance/sensitivity/reliability引用本文复制引用
出版年
2024
NETL
NSTL
万方数据