Application of REI Equivalent in Reactive Power Optimization Control in Regional Power Grid

Aiming at regional power grid whose power supply is a substation that connects the upper and lower grid, REI (Radial Equivalent Independent) equivalent is applied to voltage and reactive power optimization control, and varying-intercept linear regression method is proposed to obtain equivalent parameters according to local data taking into account the difficulty of getting the upper grid operating parameters. Without the information of the upper grid, this model can reflect the characteristics of voltage and reactive power of the boundary bus; enable the lower grid to regulate the voltage of the boundary bus; and make the calculated voltage of the whole grid more accurate. Compared with conventional model, this model only adds one node in optimization calculation, so it´s simple and practical.