Obtaining robust performance of a current fed voltage source inverter for virtual inertia response in a low short circuit ratio condition

Clint Z. Ally (Corresponding author), Erik C.W. de Jong

Research output: Contribution to journalArticleAcademicpeer-review

18 Downloads (Pure)

Abstract

Low inertia levels are typical in island power systems due to the relatively small rotational generation. Displacing rotational generation units with static inertia-less PV power results in a significant increase in the frequency volatility. Virtual inertia provided by inverter-storage systems can resolve this issue. However, a low short circuit ratio (SCR) at the point of common coupling together with a fast phase locked loop (PLL) will compromise the response performance of the system. To address this issue, a robust PI controller (RPI) for the inner current-loop of a current fed grid-con-nected inverter is proposed. The PLL disturbance and grid impedance are incorporated into a single model and recast to a generalized representation of the system, thereby allowing easy tuning of the RPI by the mixed sensitivity H∞ method. The performance of the RPI is compared with that of a PI controller (PI) tuned by the regular loop-shaping method. The results show that when the SCR is above 10, the performance of both controllers is equivalent. However, lowering of the SCR compro-mises the performance of the system with PI and it becomes underdamped at SCR < 2. On the con-trary, the system with the RPI is capable of maintaining the nominal performance throughout the same SCR decrease.

Original languageEnglish
Article number5546
Number of pages18
JournalEnergies
Volume14
Issue number17
DOIs
Publication statusPublished - Sep 2021

Keywords

  • Current fed inverter
  • Robust control
  • Virtual inertia
  • Weak grid

Fingerprint

Dive into the research topics of 'Obtaining robust performance of a current fed voltage source inverter for virtual inertia response in a low short circuit ratio condition'. Together they form a unique fingerprint.

Cite this