A Dynamic-Inductive-Compensation-Based Method for Improving Tap-off Power from Insulated Ground Wires of Overhead High Voltage Transmission Lines

Lack of stable and high power supply for large-scale online monitoring and inspection devices, will restrict the development of intelligent operation and maintenance technology for transmission lines. Tapping power from the insulated ground wire of high-voltage overhead transmission lines by electrostatic induction and inductive compensation, is expected to be one of the possible ways to solve this problem. By taking the effects of the line sags and landform on the equivalent circuit parameters of power tapping into consideration, this paper investigates a dynamic-inductive-compensation method for improving the tap-off power from insulated ground wires of overhead high voltage transmission lines, by employing a magnetic powder core to achieve a self-adaptive negative-feedback regulation. The field-circuit coupled transient simulation is performed to verify the proposed method by varying the load resistance at the low-voltage side from 1 Ω to 50 Ω. The simulation results show that when the equivalent capacitance decreases from 19.4 nF to 17.5 nF, the maximum tap-off power decreases from 977.6 W to 819.4 W, and the maximum ground-wire voltage increases from 35.93 kV to 37.57 kV.