Transmission Line Impedance Calculation in Per Unit (pu)

How can the series impedance of a transmission line be expressed in per unit (pu)?

What are the base values used for the calculation?

Series Impedance in Per Unit (pu)

To express the series impedance of a transmission line in per unit (pu), we need to divide the impedance by the corresponding base values of voltage and power. In this case, the base values provided in the data are 148 kV (line) for voltage and 34 MVA (three-phase power) for power.

The series impedance of a transmission line is represented by Z = 19 + j62 Ω. To calculate the impedance in per unit (pu), we divide it by the base voltage and power values. This helps to normalize the impedance values and compare them relative to the base values.

By using the base voltage of 148 kV (line) and base power of 34 MVA (three-phase power), we can calculate the per unit impedance magnitude. In this case, the per unit impedance magnitude is calculated to be 128.38 pu.

Per unit calculations are essential in power systems analysis as they simplify the comparison and analysis of impedance values with respect to the defined base values. By converting the impedance into per unit, we can better understand the performance of the transmission line and make informed decisions for optimization.