International Journal of Innovative Research in Electrical, Electronics, Instrumentation and Control Engineering (IJIREEICE)
Now-a-days, demand for electric power has shown steady but geographically uneven growth. The wheeling of the available energy through existing long AC lines to load centers has a certain upper limit due to stability considerations. Thermal limit is the major limit to be considered while increasing loadability of existing EHV long transmission lines. Thus, these lines cannot be loaded to their thermal limit to keep sufficient margin against transient instability. This paper presents the concept of composite AC-DC power transmission. The conductors are allowed to carry usual AC along with DC superimposed on it.