The Effect of Load Power Factor on the Efficiency of Three-Phase Four-Wire Power System with Shunt Active Filter

摘要

The formula for determining efficiency of three-phase four-wire power system for unbalanced non-sinusoidal mode with a given load power factor and the known ratio of short circuit power to load active power has been derived. The new formula of the apparent power, which takes into account the power losses of the neutral conductor, has been used in order to determine the power factor. The adequacy of the proposed ratios is shown in the example of calculation of efficiency of three-phase four-wire power system for a simple unbalanced load. Analytical condition for the energy feasibility of a shunt active power filter (SAF) to improve the efficiency of the power system has been derived.