Dynamic Virtual Power Plant Design for Fast Frequency Reserves: Coordinating Hydro and Wind

TL;DR

This paper proposes a dynamic virtual power plant design that coordinates hydro and wind resources to provide fast frequency reserves, ensuring grid stability without additional storage or curtailment.

Contribution

It introduces a decentralized model matching approach for integrating fast and slow reserves in a DVPP considering device limitations.

Findings

DVPP effectively coordinates wind and hydro reserves.

System stability maintained during a 1400 MW disconnection scenario.

No need for battery storage or wind curtailment.

Abstract

To ensure frequency stability in future low-inertia power grids, fast ancillary services such as fast frequency reserves (FFR) have been proposed. In this work, the coordination of conventional (slow) frequency containment reserves (FCR) with FFR is treated as a decentralized model matching problem. The design results in a dynamic virtual power plant (DVPP) whose aggregated output fulfills the system operator (SO) requirements in all time scales, while accounting for the capacity and bandwidth limitation of participating devices. This is illustrated in a 5-machine representation of the Nordic synchronous grid. In the Nordic grid, stability issues and bandwidth limitations associated with non-minimum phase zeros of hydropower is a well-known problem. By simulating the disconnection of a 1400 MW importing dc link, it is shown that the proposed DVPP design allows for coordinating fast FFR from wind, with slow FCR from hydro, while respecting dynamic limitations of all participating devices. The SO requirements are fulfilled in a realistic low-inertia scenario without the need to install battery storage or to waste wind energy by curtailing the wind turbines.