Analysis of ion flow field of UHV/EHV AC transmission lines

In this work, the calculation method of the ion flow field of AC transmission lines based on the charge simulation method is improved. As the previous works, the problem is solved in time domain with representing the space charges as discrete line charges. In each discrete time step, the procedures of charge emission, space charge displacement, and space charge recombination are simulated. As improvements, the influence of the conductor surface field uniformity on corona discharge is taken into account, so that the ion flow field of multi-phase or bundle conductors can be simulated in this work. The corona losses of a 3-phase 8-conductor bundle HVAC transmission line is calculated. Acceptable agreement is obtained with the experimental results. The ground level total electric field of different line configurations is calculated. The influences of line configurations such as subconductor radius, bundle spacing, number of subconductors, wire spacing, and phase height on ground level total electric field are analyzed based on the calculation.