Secondary Arc Effects in AC/DC Hybrid Transmission
With obtaining a permit for construction of new overhead transmission lines being a lengthy process in many countries, there is incentive to consider use of dc transmission as a means to upgrade and significantly expand the power transfer capability of existing ac circuits. There is a good chance that a transmission circuit converted to dc will be coupled to a parallel ac circuit on the same tower or right-of-way. Electromagnetic coupling from the ac circuit to the dc circuit may effect the performance of the dc transmission line unless specific design considerations are instigated. Of concern is extinction of the secondary arc when a dc pole conductor is faulted. Will the coupling from an ac circuit maintain the arc?
D. Woodford, “Secondary Arc Effects in AC/DC Hybrid Transmission”, IEEE Transactions on Power Delivery, April 1993, Vol. 8, No. 2, pp 704- 711.