融合灭弧信息的有源串联接地配电网故障检测方法

Fault Detection Method of Active Series Grounding Distribution Network Combining the Arc Extinguishing Information

为了优化有源全补偿消弧设备和挖掘灭弧状态信息包含的故障特征,该文提出基于串联分压的配电网消弧原理及融合灭弧状态信息的接地故障检测方法。提出采用单个H桥变流器与消弧线圈串联的有源降压消弧全补偿方法和灵活接入保护电容的有源消弧装置保护方案,在消弧原理与控制、设备承压与安全、功率输出与过压防护等方面表现出良好性能。提出融合有源降压消弧全补偿“伪正常”状态信息的接地故障检测方法,利用系统正常-故障-灭弧3种状态信息构造故障检测判据,在免受过渡电阻和分布参数不对称影响的基础上优化故障检测方式和提高故障检测效率,无需线路间信息的横向比较即可实现系统全域零序导纳测量、故障馈线独立判别和故障程度跟踪识别。仿真实验证实了方法的有效性,为优化配电网有源消弧和接地故障检测提供创新方案。

To optimize the active fully compensated arc extinguishing equipment and explore the fault features contained in the arc extinguishing status information,an arc suppression device based on series voltage division and a grounding protection method based on fusing arc extinguishing state of the distribution network were proposed.The full compensation for active voltage reduction and arc elimination method was proposed using a single H-bridge converter in series with the arc suppression coil.The voltage reduction protection scheme of the active arc suppression device connected with the protective capacitor was proposed,which has good performance in the principle and control of arc suppression,equipment pressure and safety,power output,and overvoltage protection.An improved zero-sequence admittance method was proposed,which fused the pseudo-normal state information generated by the full compensation for active voltage reduction and arc elimination.The fault detection criterion is constructed by using three-state information of normal,fault,and arc elimination of the system,which can optimize the method of fault detection and improve its efficiency,avoiding the influence of transition resistance and asymmetry of distribution parameters.Besides,the whole-area zero-sequence admittance measurement,the independent selection of faulty feeders and fault degree identification can be realized without horizontal comparison of information between lines.Simulation results show that the method is effective,which provides a theoretical basis for optimizing active arc suppression technology and enriching grounding protection methods.