基于交叉重叠差分变换的分布式电源系统接地故障检测方法  

Ground Fault Detection Method of Distributed Power System Based on Sequential Overlapping Derivative Transform

作　　者：黄海燕 龚振 黄永泉 苏适 谢青洋 尚磊 HUANG Haiyan;GONG Zhen;HUANG Yongquan;SU Shi;XIE Qingyang;SHANG Lei(Kunming Power Supply Bureau of China Southern Power Grid Corporation,Kunming 650000;Department of Electrical Engineering,Tsinghua University,Beijing 100084;State Key Laboratory of Power System Operation and Control(Tsinghua University),Beijing 100084;TBEA Xinjiang SunOasis Co.,Ltd.,Xi’an 710117;Electric Power Research Institute,Yunnan Power Grid Co.,Ltd.,Kunming 650217;School of Electrical Engineering and Automation,Wuhan University,Wuhan 430072)

机构地区：[1]云南电网有限责任公司昆明供电局,昆明650000 [2]清华大学电机工程与应用电子技术系,北京100084 [3]新型电力系统运行与控制全国重点实验室(清华大学),北京100084 [4]特变电工新疆新能源股份有限公司,西安710117 [5]云南电网有限责任公司电力科学研究院,昆明650217 [6]武汉大学电气与自动化学院,武汉430072

出　　处：《电气工程学报》2025年第1期188-196,共9页Journal of Electrical Engineering

基　　金：云南电网公司科技、国家资助博士后研究人员计划(GZC20231212);新型电力系统运行与控制全国重点实验室(YNKJXM20222105)资助项目。

摘　　要：在不接地系统中,发生小故障角故障或高阻接地故障时故障电流较小,传统故障检测方法仅设一个阀值,对这类故障适应性不强,检测可靠性受限;在含分布式电源的系统中,受电力电子元件的限制,故障电流的幅值也将减小。所提方法将暂态零模电流在不同频带上的最大能量和对应的频率范围定义为特征频带,对比不同类型故障下故障线路与非故障线路的特征频带内零模电流,利用交叉重叠差分变换(Sequential overlapping derivative, SOD),突出其相位、幅值差异,实现故障检测。仿真表明,特征频带可以有效地过滤信号干扰并突出故障特征,对以上故障类型均能有效甄别;另一方面,SOD只需提取几个采样点的电流电压信号,即可快速识别故障初始行波,避免初始行波易逝性带来的问题。In the ungrounded system,the fault current is small when the small fault angle fault or high-impedance grounding fault occurs,and the traditional fault detection method only sets a threshold,which is not adaptive to the fault characteristics and the detection reliability is limited.In systems with distributed power generation,the amplitude of the fault current is also reduced due to the limitations of the power electronics.The proposed method defines the maximum energy and corresponding frequency range of the transient zero-mode current in different frequency bands as the characteristic frequency bands, comparing the zero-mode currents in the characteristic frequency bands of the faulty lines and non-faulty lines under different types of faults, and using the sequential overlapping derivative(SOD) to highlight the phase and amplitude differences to realize fault detection. The simulation results show that the characteristic frequency bands can effectively filter the signal interference and highlight the fault characteristics, and can effectively identify the above fault types. On the other hand, SOD only needs several sampling points of current and voltage signals to quickly identify the initial traveling wave and avoid the problem caused by the fleeting nature of the initial traveling wave.

关 键 词：故障检测 高阻抗接地故障 小故障角故障 特征频带 交叉重叠差分变换 分布式电源 

分 类 号：TM7[电气工程—电力系统及自动化]