Location of Shield Wires for Unconventional High Capacity Transmission Lines

To achieve net-zero emission in America by 2050, high voltage transmission capacity must expand ~60% by 2030 and triple by 2050 to connect further wind and solar facilities to demand. This expansion requires a capital investment in transmission capacity of $360 billion by 2030 and $2.4 trillion by 2050. Considering the high cost of building transmission lines, innovations toward high-capacity overhead lines have been targeted to reduce the number of transmission lines required. In our previous studies, we introduced unconventional high-capacity transmission lines. To realize these novel transmission lines, various aspects of line design should be studied, and this paper addresses determining the location and number of shield wires to protect these novel lines against lightning strikes. Lightning-induced overvoltage across line insulators is one of the key factors in power system outages. The design meets the shielding failure flashover rate (SFFOR)
$\leq 0.05/100$
km-years for all three phases of the unconventional high-capacity transmission line. Brown-Whitehead equations were used to measure and analyze the striking distance for vertical strokes.