基于AMR双向阵列的配电网零序电流检测方法

Zero-sequence current detection method of distribution network based on AMR bidirectional array

配电网发生单相接地故障时,由于故障电流较小,现有装置无法准确采集故障电流信息,因此提出了一种补偿电磁干扰的零序电流检测方案,以提高零序电流测量精度.该方法采用3个由AMR双向阵列组成的电流传感器,利用每个阵列采集的三相电流合成零序电流.首先建立了测量电流的数学模型,通过Matlab数值模拟确定了传感器阵列的布置位置,并基于此提出零序电流测量方案;然后利用Simulink建立了10 kV小电流接地系统仿真模型,分析该方案的零序电流测量误差;最后通过不同方案试验数据的对比,验证了该方案的准确性.理论分析与仿真试验结果表明该方法能够有效、准确地检测零序电流.

When single-phase grounding fault occurs in distribution network, the fault current information cannot be collected accurately by existing devices due to the small fault current. Therefore, a zero-sequence current detection scheme for compensating electromagnetic interference was proposed to improve the measurement accuracy of zero-sequence current.Three AMR bidirectional array current sensors were used to synthesize zero-sequence current.The mathematical model of measuring current was established, and the location of sensor array was determined by Matlab numerical simulation to propose a zero-sequence current measurement scheme.The simulation model of 10 kV small current grounding system was established by Simulink, and the zero-sequence current measurement error of the scheme was analyzed.The proposed scheme was verified by comparing the experimental data of different schemes. The theoretical analysis and simulation results show that the proposed method can detect zero-sequence current effectively and accurately.