Generalized Model of VSC-based Energy Storage Systems for Transient Stability Analysis

TL;DR

This paper introduces a comprehensive generalized model for various energy storage systems using linear DAEs, enabling accurate transient stability analysis of power systems with different storage technologies.

Contribution

The paper develops a unified, accurate model for multiple energy storage technologies that includes VSC and dc link dynamics for stability analysis.

Findings

Model accurately predicts angle and voltage stability.

Includes a balanced VSC and dc link dynamics.

Validated with WSCC 9-bus system case study.

Abstract

This paper presents a generalized energy storage system model for voltage and angle stability analysis. The proposed solution allows modeling most common energy storage technologies through a given set of linear differential algebraic equations (DAEs). In particular, the paper considers, but is not limited to, compressed air, superconducting magnetic, electrochemical capacitor and battery energy storage devices. While able to cope with a variety of different technologies, the proposed generalized model proves to be accurate for angle and voltage stability analysis, as it includes a balanced, fundamental-frequency model of the voltage source converter (VSC) and the dynamics of the dc link. Regulators with inclusion of hard limits are also taken into account. The transient behavior of the generalized model is compared with detailed fundamental-frequency balanced models as well as commonly-used simplified models of energy storage devices. A comprehensive case study based on the WSCC 9-bus test system is presented and discussed.