Question

The current supplied to the transmission-line capacitance is called ____.

Short answer

Therefore, the correct word is charging current.

Step-by-step solution

Define the term charging current

For a single-phase circuit operating at line-to-line voltage${\mathrm{V}}_{\mathrm{xy}}={\mathrm{V}}_{\mathrm{xy}}\angle 0°$ , the charging current can be written as,

$\begin{array}{c}{\mathbf{I}}_{\mathrm{chg}}={\mathbf{Y}}_{\mathrm{xy}}{\mathbf{V}}_{\mathrm{xy}}\\ ={\mathbf{j\omega C}}_{\mathrm{xy}}{\mathbf{V}}_{\mathrm{xy}}\mathbf{A}\end{array}$

Here,$Y_{xy}$ is the line admittance, ${\mathrm{V}}_{\mathrm{xy}}$ is the line voltage, ${\mathrm{C}}_{\mathrm{xy}}$ is the line capacitance, $\omega$ is the frequency.

Explain effects on charging current

Shunt admittance, primarily capacitive, affects line charging currents, which inject reactive power into the power system.

Thus, shunt reactors (inductors) must be installed in order to protect line from the reactive power due to charging current and the system more energy efficient.

The current supplied to the transmission-line capacitance is called charging current.

Hence, the correct word for the blank is charging current.