不借助如聚磁环等辅助装置,直接利用磁传感器组来测量载流导体周围的磁场,进而反算待测电流是电力系统大电流测量的一种新思路。为了快速计算电流,尤其是电力系统中常见的瞬态电流,同时确保测量的准确性,文中研究了测量频带内磁场分布的动态特性,在时域中建立了基波电流与磁场幅值对应关系的瞬态电流计算模型。以三相矩形母排系统为例,研究了该测量模型适用的磁传感器组放置区域,并分析了误差的来源。最后利用实验验证了该模型的有效性。
Without any field concentrate equipment,a novel current transducer based only on solid-state magnetic sensor array has been explored recently in the field of power system high current measurement.Aiming at reconstructing the transient current faster without sacrificing the measurement accuracy,an advanced measurement model in time domain,based on the trans-impedance at 50 Hz is proposed.In this model,the dynamic behavior of the magnetic field in the measurement range is investigated.The optimal region for locating the sensors in a three-phase rectangular bus-bar testing system is calculated, where the measurement model complies with the measurement specification.Theoretical error analysis is carried out with the help of numerical and experimental results and the final results validate the effectiveness of the theory proposed.