The model of electrical loads in the steady-state regime rating of electric grids with capacitive current compensation

A mathematical model of the three-phase electrical load intended to calculate the modes of electric grids with controlled arc extinguish reactors considering the asymmetry parameters of overhead lines. When developing the model the assumption was made that normal mode of power load is constant. It makes possible to minimize the set of input data. The load current equations are derived from a combination of methods of phase coordinates and symmetrical components. The model of normal mode implemented a linear transformation of the phase load voltages at the phase currents with consecutive exception of voltage and residual currents. It was found that even when there is considering voltage on arc extinguish reactor the mathematical model gives practically symmetrical load currents. The developed model of the electrical load can be used to calculate the normal mode of the grid with compensated neutral, as well as to calculate the transient currents and steady modes of a single-phase earth fault.