电力电缆在线监测系统的感应取电电流互感器参数选择与优化

Parameter Selection and Optimization of Energy Harvesting Current Transformer for Power Cable On-line Monitoring System

针对电缆线路在线监测系统感应取电的电流互感器(TA)参数选择问题,通过建立TA的简单拓扑模型,得到TA二次侧电压波形接近方波,可据此计算流入整流滤波电路的电流平均大小,并进一步推导负载获得最大功率条件,及励磁电抗和一次电流、负载电压和电阻之间的数学关系。通过考虑大电流工况限制及限定启动电流使负载电压和输出功率最大化等约束条件,确定感应取电TA的参数。仿真和试验证明了该方法能够精确计算TA取电装置的启动电流,并使负载工作点高度趋近功率峰值。

In view of the problem of selecting parameters of current transformer induced by cable lines’ on-line monitoring system, by establishing a simple topological model of TA, the secondary side voltage waveform of TA is obtained, which is close to square wave. Based on this, the average current size of the inflow rectifier filter circuit can be calculated, and the maximum power condition of the load can be derived, and the mathematical relationship between excitation reactance and primary current, load voltage and resistance can be deduced. The parameters of inductive TA are determined by considering the constraints of high current condition and limiting starting current to maximize the load voltage and output power. Simulation and experiments show that the proposed method can accurately calculate the starting current of the TA device and make the load operating point approach the peak power.