Phasor-Based Optimal Voltage Control for Distribution Grids Through D-PMUs and EV Battery Charger

Abstract

This paper focuses on an optimal control scheme to improve the voltage profile of distribution networks by coordinating the reactive power injection from electric vehicle (EV) chargers and the remote sensing of the voltage magnitude by using phasor measurement units at distribution level (D-PMUs). Then, the eigensystem realization (ER) algorithm provides the identification of the distribution grid (DG) by taking advantage of time-synchronize measurements stemming from D-PMUs. Meanwhile, the linear quadratic Gaussian (LQG) controller with multiple inputs and multiple outputs (MIMO) minimizes the states and regulate the outputs by establishing a phasor-based optimal voltage control in fulfillment with the Bellman's principle. The effectiveness of the optimal control scheme is demonstrated by testing simulated scenarios on the IEEE 13- node test benchmark feeder. The achieved results exhibit a compensation of the voltage profile at the millisecond scale in the presence of three-phase faults and significant load increments.