Techno-Economic Comparisons of HVAC and Simultaneous AC-DC Transmission

Table 2

HVAC corona loss calculation parameters.

Symbol	Parameter	Value
	Rated voltage	400 kV
	Height of conductor above ground	3500 cm
	Phase spacing	850 cm
	Radius of conductor	1.9 cm
	Air density correction factor at t = 40° and P = 727 torr
	Distance between component conductor centers	40 cm
	Number of component conductors in bundle	2
	Factor for multiple conductors	0.5475
	Outside radius of bundle	20 cm
	Equivalent radius of bundle conductor	17.43 cm
	Conductor surface voltage gradient	17.15 kV/cm
	Irregularity factor for disruptive critical voltage [18]	0.85
	Geometric mean distance for a three-phase line	10.109 m
	Geometric mean radius of bundle conductors	0.077 m