Optimal Allocation of Virtual Inertia Devices for Enhancing Frequency Stability in Low-Inertia PowerSystems

TL;DR

This paper proposes an optimized method for allocating virtual inertia devices in low-inertia power systems to enhance frequency stability, leveraging a reduced model based-norm algorithm and demonstrating effectiveness on a standard test system.

Contribution

It introduces a novel reduced model based-norm algorithm for optimal virtual inertia allocation considering Fiedler mode impact in power systems.

Findings

The proposed RMHA improves frequency stability in low-inertia systems.

Case studies show effective virtual inertia placement on IEEE 24-bus system.

The method enhances system resilience against frequency excursions.

Abstract

As renewable resources gradually replace conventional generation based synchronous machines, the dynamics of the modern grid changes significantly and the system synchronous inertia decreases substantially. This transformation poses severe challenges for power system stability; for instance, it may lead to larger initial rate of change of frequency and increase frequency excursions. However, new opportunities also arise as novelconverter control techniques, so-called grid-forming strategies, show higher efficiency and faster response than conventional synchronous generators. They mainly involve virtual inertia (VI) emulation to mimic the behavior of synchronous machines. In this study, a state-space model for the power system network is developed with VI as a frequency regulation method. A reduced model based-norm algorithm (RMHA) considering the Fiedler mode impact is proposed in this paper to optimize the allocation of VI devices and improve power system frequency stability. Finally, case studies conducted on the IEEE 24-bus system demonstrate the efficacy of the proposed RMHA approach.