A novel inversion evaluation method for transformer DC magnetic bias treatment

In HVDC monopole operation mode, there is DC flowing through AC system transformer that grounded in neutral point. Based on the maximum allowed DC current of transformer magnetic bias, the paper proposes an inversion method to deduce the maximum allowed injection current of HVDC grounding electrodes. In addition, the detail procedures to obtain maximum injection current of grounding electrodes are given. Above all, a treatment device configuration solution is given. The solution utilizes simulation operation data of AC and DC system, and it describes an assessment of the treatment.