Fixed-Frequency Operation of an Island Grid with Multiple Grid-Forming Inverters and GPS-Based Synchronisation

authored by

R. Strunk, L. Reus, L. Hofmann, A. Mertens

Abstract

By using an external signal for the synchronisation, an island grid with grid-forming inverters (GFMs) can be operated at a constant frequency. The global positioning system (GPS) provides a periodic pulse with a suitable accuracy. This is used to define the grid frequency and a reference for the voltage phase angle. A digital counter in the control hardware determines the phase angle. The counter is reset by each pulse of the GPS. An active power-angle droop control leads to partial power sharing between the GFMs and reduces distortions caused by non-ideal synchronisation. Furthermore, the grid operator can adjust the voltage reference phasors of the GFMs to control the power flow in the grid. An island grid with two GFMs and a hydro power plant is studied in simulations. The investigated power system is an altered and simplified grid model of Suðuroy, in the Faroe Islands. The effects of a load connection and a distorted GPS synchronisation are studied. Stable operation of the power system using the fixed-frequency approach is demonstrated.

Organisation(s)

Power Electronics and Drive Control Section
Electric Power Engineering Section

Type

Conference contribution

Pages

30-36

No. of pages

7

Publication date

2023

Publication status

Published

ASJC Scopus subject areas

Engineering(all)

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1049/icp.2023.1430 (Access: Closed)