A Market Mechanism for Virtual Inertia

TL;DR

This paper introduces a market mechanism for procuring virtual inertia in power systems, ensuring truthful bidding and fair compensation, to address the loss of rotational inertia due to renewable energy integration.

Contribution

It proposes a novel market design for virtual inertia procurement using a Vickrey-Clarke-Groves mechanism, ensuring truthful bidding and non-negative payoffs.

Findings

Mechanism guarantees truthful bidding as dominant strategy.

Ensures non-negative payoffs for virtual inertia providers.

Demonstrated effectiveness through a three-region case study.

Abstract

One of the recognized principal issues brought along by the steadfast migration towards power electronic interfaced energy sources is the loss of rotational inertia. In conventional power systems, the inertia of the synchronous machines plays a crucial role in safeguarding against any drastic variations in frequency by acting as a buffer in the event of large and sudden power generation-demand imbalances. In future power electronic-based power systems, the same role can be played by strategically located virtual inertia devices. However, the question looms large as to how the system operators would procure and pay for these devices. In this article, we propose a market mechanism inspired by the ancillary service markets in power supply. We consider a linear network reduced power system model along with a robust $\mathcal{H}_2$ performance metric penalizing the worst-case primary control effort. With a social welfare maximization problem for the system operator as a benchmark, we construct a market mechanism in which bids are invited from agents providing virtual inertia, who in turn are compensated via a Vickrey-Clarke-Groves payment rule. The resulting mechanism ensures truthful bidding to be the dominant bidding strategy and guarantees non-negative payoffs for the agents. A three-region case study is considered in simulations, and a comparison with a regulatory approach to the same problem is presented.