Transmission lines comparison: case of the actual three-phase against a potential nine-phase systems

Abstract

The importance of power systems in our daily life is no longer needed to be demonstrated and the companies that practice in this field are among the largest in the world. Today, all these companies would like to transmit more electricity to consumers but are sometimes forced to build several lines in parallel with the main transmission line. Using this solution is not without impact for biodiversity and this way of doing has some limitations. This study compares the results obtained from four different types of transmission lines in order to optimize power transfer. Those lines are characterized by their power transmitted and their number of phase as well as their length. Lines 1 and Line 2 have 120 km length and carry 400 kV respectively in three-phase system for line 1 and in nine-phase system for line 2 while lines 3 and 4 have 600 km length and carry 750 kV respectively in three-phase system for line 3 and nine-phase system for line 4. Results show that the increase in the number of phases could help supplying up to eight and six times respectively for short and long transmission lines more load connected to the grid.