Abstract: This paper presents commutation technology of HVDC system. In the early 19th centuries HVAC system was used for the long distance transmission. Because of the more power losses in HVAC system HVDC system adopted in mid 19th century for the long distance transmission. The Thyristors are used for the commutation in HVDC system. Now advancement in thyristor capacity and by using IGBT VSC based technology HVDC system is improved.
