Advanced Local Voltage Control through Polynomial P-Var Functions

Reactive power control of inverter-based equipment, such as photovoltaic units or electric vehicles, is one way to address increasing voltage violations in distribution grids. Local droop control strategies have been rolled out in several European countries. In this work, we present an advanced method to define polynomial P-Var curves. A stochastic optimal power flow problem is solved, which co-optimizes both voltage deviations and distribution grid losses, and incorporates the polynomial coefficients as decision variables. The proposed method is applied to a real Danish low voltage feeder, leading to more robust solutions.