1.河海大学能源与电气学院,江苏省南京市 211100;2.智能电网运行与控制湖南省重点实验室(长沙理工大学),湖南省长沙市 410114
为了提升配电网高阻接地故障检测的灵敏度,提出基于配电线路参数不对称度跟踪监测的单相接地故障检测方法。针对配电网各线路分布参数具有随机差异性的特征,定义了表征线路参数不对称的参量,论证了配电线路形成零序电流的临界条件和流通路径,建立了计及线路参数不对称随机差异性的配电网零序网络等值运算模型,提出了配电线路对地阻抗和不对称度等参量测量方法,实现了单相接地故障选线、选相和过渡电阻测量。根据故障类型优选故障检测方案,高阻接地时人为调控零序电压提高故障检测灵敏性,低阻故障时仅依赖零序电气信息变化量快速检测故障。仿真实验结果验证了所提检测方法的有效性。
国家自然科学基金重点资助项目(51737002);江苏省自然科学基金青年基金资助项目(BK20190490);中国博士后科学基金面上项目(2020M671318)。
刘宝稳(1988—),男,通信作者,博士,讲师,硕士生导师,主要研究方向:小电流接地系统接地故障检测、消弧及中性点有源柔性控制、电气设备故障诊断。E-mail:lbw_5566@163.com
曾祥君(1972—),男,博士,教授,博士生导师,主要研究方向:电力系统微机保护与控制。E-mail:eexjzeng@qq.com
马宏忠(1962—),男,博士,教授,博士生导师,主要研究方向:电气设备状态监测与故障诊断、电能质量监控等。
1.College of Energy and Electrical Engineering, Hohai University, Nanjing 211100, China;2.Hunan Key Laboratory of Smart Grid Operation and Control (Changsha University of Science and Technology), Changsha 410114, China
In order to improve the sensitivity of high-resistance grounding fault detection in distribution networks, a single-phase grounding fault detection method for tracking and monitoring parameter asymmetry of distribution lines is proposed. Aiming at the random difference characteristics of distribution parameters of lines in the distribution network, the parameters characterizing the parameter asymmetry of lines are defined, the critical conditions and flow path of generating zero-sequence current of distribution lines are demonstrated, the equivalent operation model of the zero-sequence network for the distribution network considering the asymmetric random difference of line parameters is established, and the measurement methods of parameters such as distribution line impedance to ground and asymmetry are proposed to realize single-phase grounding fault line selection, phase selection and transition resistance measurement. The fault detection scheme is optimized according to the fault types. In the case of high-resistance grounding, the zero-sequence voltage is artificially adjusted to improve the sensitivity of fault detection. In the case of a low-resistance fault, the fault is quickly detected only relying on the change of zero-sequence electrical information. Simulation experiment results verify the effectiveness of the proposed detection method.
[1] | 刘宝稳,曾祥君,马宏忠,等.参数不对称配电线路的等效模型与接地故障检测方法[J].电力系统自动化,2022,46(13):159-167. DOI:10.7500/AEPS20210923004. LIU Baowen, ZENG Xiangjun, MA Hongzhong, et al. Equivalent Model and Grounding Fault Detection Method for Distribution Lines with Asymmetry Parameters[J]. Automation of Electric Power Systems, 2022, 46(13):159-167. DOI:10.7500/AEPS20210923004. |