Reconstruction Strategy for Transmission Line Currents with Non-invasive Detection

To realize non-contact detection of high-voltage transmission line currents, a transmission line current reconstruction strategy based on magnetic sensors is proposed. Initially, a catenary model of the sagging state is established by analyzing the force on the transmission line. Subsequently, a detailed three-dimensional spatial magnetic field model of the conductor is derived according to the Biot-Savart electromagnetic law. Furthermore, a current reconstruction strategy for transmission lines based on the RLS-NSGA-III algorithm is proposed. The collected magnetic field data are corrected using the RLS algorithm to reduce the impact of sampling errors. The NSGA-III algorithm can simultaneously determine the three-phase current of the transmission lines, achieving high precision and convergence. Lastly, the feasibility and accuracy of the proposed transmission line magnetic field model and current reconstruction strategy are validated through simulations and experiments. The experimental results show that by detecting the magnetic field of the transmission line, the reconstructed three-phase current of the wire can be obtained with a maximum error of 2%, and accurate detection can still be achieved in situations such as those involving an unbalanced three-phase current of the transmission line.