Research Summary on Transformer DC Magnetic Bias and Suppression Technology

Under the rapid development of the power system, China has built a complex DC and AC hybrid transmission system. The scale of DC transmission system construction has gradually increased. Once the DC magnetic bias happens, the excitation current distortion of the transformer, the core and metal components will have a few faults for instance temperature increase, loss increase, vibration intensification, etc, which threatens the safe operation of the transformer. In view of this problem, this paper discusses the basic concept and generation mechanism of DC magnetic bias, analyzes its influence on transformer excitation current, temperature rise, loss, vibration and other four aspects and related research results, and finally expounds the research, existing problems and development prospects of suppression technology.