An ADMM-based Regularized State Estimation Scheme for the Distribution Grid

In this paper, we propose a novel state estimation (SE) scheme for the distribution grid. It exclusively leverages on measurements from mu PMUs (micro Phasor Measurement Units) making it possible to operate at a faster time scale than conventional SE approaches based on legacy measurements. To circumvent observability issues, we realize that the voltage drop in adjacent buses is limited and, on that basis, we formulate a SE regularized weighted total variation estimation (WTVSE) problem. The problem can be iteratively solved by resorting to the so-called Alternating Direction Method of Multipliers (ADMM). Further, we provide closed-form expressions for the updates of the primal and dual variables. The performance of the proposed scheme is numerically assessed on a 95-bus distribution system for a number of realistic conditions of noise, load and photovoltaic generation profiles. A number of benchmarks are provided, as well.