Monitoring Modeling and Analysis of Electromagnetic Environment of HVDC Transmission Lines Based on Ion Flow and Wind Coupling Field

Ziyi Qin ^1* Jiong Chen ¹ Maoxin Ren ² Fan Yin ²

• ¹ Shanghai University of Electric Power, Shanghai, China
• ² East China Branch, State Grid Corporation of China, Shanghai, China

High-voltage direct current transmission line is an integral part of the power system, but the ion flow field and total electric field it generates can be harmful. Moreover, two of the most critical indicators for evaluating environmental compatibility, ion current density ρj and total electric field strength E, can be affected by wind. The difficulty in monitoring and modeling the ion flow and wind coupling field makes the recent research considering only transverse winds, which is not able to take into account the wind directions, and cannot model the actual situation accurately for monitoring and analysis. For this reason, this paper takes the ±800kV Jinsu Line in Huzhou as an example and constructs a 3-D monitoring model using the finite element method. The nonlinear mapping relationship between the model-design parameters and the feature parameters is approximated by extreme learning machine, and the actual measurement results are used to invert the model-design parameters in order to modify the finite element model, so as to realize the precise monitoring of the ρj and E in different wind speeds and directions situation. The results show that the modified model can realize the condition monitoring of the electromagnetic environment of transmission lines with an improved accuracy of 20.86%, and some laws are discovered: the peak absolute value of ρj and E increase and then decrease with the increase of wind speed; at low wind speed, the smaller the included angle between the wind direction and the line direction is, the smaller the peaks are; at high wind speed, the smaller the included angle is, the peaks increase and then decrease.