摘要
用磁传感器测量三芯电力电缆各芯线的电流时,磁传感器阵列的中心可能偏离电缆中心,致使测量结果中含有由此产生的误差即偏心误差,为此提出一种对偏心误差的计算和补偿方法。在原有测量方法基础上,将磁传感器阵列沿电缆轴向安装表面旋转180°,测量新位置上的磁感应强度。通过求解非线性方程组,可以确定偏心误差的大小;并据此对测量结果进行补偿,可得到计及偏心误差情况下三芯电力电缆各芯线电流值的实际大小。电磁场有限元仿真试验结果表明,所建立的解析模型具有很好的准确性,验证所提出计算和补偿方法的有效性。
When magnetic sensors are used to measure the current of each core of a three-core power cable, the center of the magnetic sensor array may deviate from the center of the cable, resulting in errors in the measurement results, i.e., eccentric error. For this reason, a method for calculating and compensating the eccentric error is proposed. Based on the original measurement method, the magnetic sensor array is rotated180° along the axial installation surface of the cable, and the magnetic flux density at the new position is measured. By solving the nonlinear equations, the value of eccentric error can be determined. Based on this, the measurement results can be compensated, and the actual value of the current of each core of the three-core power cable under the condition of eccentric error can be obtained. The results of electromagnetic field finite element simulation test show that the analytical model established has good accuracy, which verifies the effectiveness of the proposed calculation and compensation method.
引文
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