Ultra-high Voltage AC/DC Grids

Figure 2.8 Power loss versus transmitted power for 1000- and 500-kV transmission lines.

2.2.4 Power–Voltage Characteristics

1. Voltage and current profiles for a transmission line open-circuited at receiving end

With a transmission line open-circuited at the receiving end, ${\stackrel{·}{I}}_2=0$, Eqs. (2.35) and (2.36) may be simplified to:

$\stackrel{·}{U}={\stackrel{·}{U}}_2\cos \beta x$ (2.51)

(2.51)

$\stackrel{·}{I}=\mathrm{j}\frac{{\stackrel{·}{U}}_2}{Z_{\mathrm{C}}}\sin \beta x$ (2.52)

(2.52)

Assuming that the line length is l, the voltage ${\stackrel{·}{U}}_1$ and current ...