A Two-Step Distribution System State Estimator with Grid Constraints and Mixed Measurements

TL;DR

This paper introduces a two-step state estimation method for large-scale unbalanced distribution systems that integrates mixed measurements and grid constraints, improving accuracy and computational efficiency.

Contribution

A novel two-step approach that efficiently incorporates mixed real-time measurements and physical grid constraints into distribution system state estimation.

Findings

Effective on benchmark test feeders

Handles unbalanced 3-phase systems

Improves estimation accuracy

Abstract

In this work we study the problem of State Estimation(SE) in large-scale, 3-phase coupled, unbalanced distribution systems. More specifically, we address the problem of including mixed real-time measurements, synchronized and unsynchronized, from phasor measurement units and smart meters, into existing solutions. We propose a computationally efficient two-step method to update a prior solution using the measurements, while taking into account physical constraint caused by buses with no loads. We test the method on a benchmark test feeder to illustrate the effectiveness of the approach.