Fault analysis principle for twelve-phase transmission system

Nowadays there has been increased interest in the application of HPO (High Phase Order) transmission technology. The benefits of larger transmission capacity and decreased right-of-way compared to that of conventional 3-phase system are very attractive to the electricity utilities. In this paper, the 12-sequence symmetrical component method is proposed in detail based on Fortescue theory. The sequence networks are deduced and hence clearly shown. Fault analysis was then carried out and four typical faults were concretely investigated at the last. This study provides useful considerations for protection scheme design of HPO transmission system.