A Unified Control Framework for Grid-Forming Inverters

EasyChair Preprint 8977

Abstract

Two Grid-Forming (GFM) control strategies based on emulation of Synchronous Machine (SM) behavior, namely Droop Control and Synchronverter, and two Andronov-Hopf Dispatchable Virtual Oscillator Control (dVOC)-based techniques are unified into a compact yet generalized control framework for GFM inverters. In the light of the proposed framework, we reassess the control laws of the studied GFM analytically, and further validate these analyzes in silico for steady-state power sharing and transient responses. We show how the mathematical structures of the studied GFM methods differ and resemble, which has an impact on the underlying grid forming performance. These differences are attributed to intrinsic nonlinearities, which can be translated as operating point parameter dependence for each GFM technique being recast for the suggested framework. Furthermore, we show that, to a certain extent, the techniques can be parameterized to have similar steady-state and dynamic responses. This work succeed in developing a technology-agnostic metrics for steady-state power sharing and dynamic behaviors of GFM methods, an important requisite for the interoperability of grid-connected inverter units.

Keyphrases: Grid-forming control, Virtual oscillator control, droop control, synchronverter

@booklet{EasyChair:8977,
  author    = {Armando José Gomes Abrantes Ferreira and Alexandre Cunha Oliveira and Antonio Marcus Nogueira Lima},
  title     = {A Unified Control Framework for Grid-Forming Inverters},
  howpublished = {EasyChair Preprint 8977},
  year      = {EasyChair, 2022}}