A method used extensively in power system analysis simplifies calculations by normalizing voltage, current, impedance, and power to a common base. This approach expresses quantities as dimensionless ratios of their actual values to selected base values. For instance, if a system has a base voltage of 13.8 kV and a measured voltage of 13.0 kV at a particular point, the normalized voltage would be approximately 0.94 per unit.
This normalization offers significant advantages. It often results in component impedances falling within a narrower range, reducing the possibility of numerical errors and facilitating easier comparison of different system elements. Furthermore, it simplifies the analysis of systems with multiple voltage levels by eliminating the need to repeatedly refer impedances to a common voltage base. Historically, before the widespread availability of powerful computing resources, the method proved invaluable for hand calculations, streamlining complex power system studies.
