Data-driven Small-signal Modeling for Converter-based Power Systems

TL;DR

This paper presents a comprehensive data-driven methodology using decision trees and spline regression to develop small-signal models for converter-based power systems, enabling efficient stability analysis across various operating conditions.

Contribution

It introduces a step-by-step procedure for creating accurate small-signal models from simulation data, validated on complex power systems with high converter penetration.

Findings

Decision Tree regression outperforms spline regression in accuracy and speed.

The methodology effectively models high-penetration converter-based power systems.

Visual representation of stability analysis results enhances understanding of system behavior.

Abstract

This article details a complete procedure to derive a data-driven small-signal-based model useful to perform converter-based power system related studies. To compute the model, Decision Tree (DT) regression, both using single DT and ensemble DT, and Spline regression have been employed and their performances have been compared, in terms of accuracy, training and computing time. The methodology includes a comprehensive step-by-step procedure to develop the model: data generation by conventional simulation and mathematical models, databases (DBs) arrangement, regression training and testing, realizing prediction for new instances. The methodology has been developed using an essential network and then tested on a more complex system, to show the validity and usefulness of the suggested approach. Both power systems test cases have the essential characteristics of converter-based power systems, simulating high penetration of converter interfaced generation and the presence of HVDC links. Moreover, it is proposed how to represent in a visual manner the results of the small-signal stability analysis for a wide range of system operating conditions, exploiting DT regressions. Finally, the possible applications of the model are discussed, highlighting the potential of the developed model in further power system small-signal related studies.