2023 journal article
Impact of Virtual Inertia on DC Grid Stability With Constant Power Loads
IEEE TRANSACTIONS ON POWER ELECTRONICS, 38(5), 5693–5699.
author keywords: Stability criteria; Power system stability; Numerical stability; Impedance; Capacitors; Voltage control; Resistors; Constant power load (CPL); dc grids; stability; virtual inertia
open access via arxiv.org (repository)
UN Sustainable Development Goal Categories
7. Affordable and Clean Energy
(Web of Science; OpenAlex)
Source: Web Of Science
Added: April 24, 2023
Virtual inertia is an effective control approach to attenuate sudden voltage changes during transient events in low-inertia dc grids. While methods have been proposed to implement virtual inertia, its impact on dc grid stability in the presence of constant power loads (CPLs) remains unclear. In this letter, we perform a rigorous stability analysis for dc grids with CPLs powered by virtual-inertia-enhanced converters. We derive a closed-form stability criterion that can be used to evaluate the impact of virtual inertia on the system stability, and demonstrate that, given a set of system parameters, the stability of a dc grid powering CPLs can be improved for a range of virtual inertia designs. We provide analytical expressions for the optimal virtual inertia that improves stability and for the maximum virtual inertia that does not deteriorate stability. In addition, we present a step-by-step guideline to design a stable dc grid with virtual inertia. Test results are presented to validate the analysis.