Research on surficial electric field of HVDC transmission lines based on the inversion method

To abandon the empirical formula applied to evaluate the corona onset value and investigate the surficial electric field on the corona conductors, the authors present an inversion algorithm to reconstruct the surficial electric field intensity from the measured data. The original ion flow field problem is reformulated into a PDE constrained optimization problem and the traditional nested-loop method is extended to solve this problem. Numerical results show that the proposed approach is robust to the noise occurred in the measurements. This approach can be applied to investigate the surficial field distribution of the HVDC transmission lines with complex configuration.