Direct vs. Indirect Control Schemes for Grid-Forming Inverters–Unveiling a Performance Comparison in a Microgrid

This article provides insights into the dynamic performance of indirect and direct control strategies for grid-forming (GFM) inverters. The indirect method for grid-forming inverters utilizes three cascaded stages to produce the reference signal sent to the PWM generator. However, the direct method...

Full description

Bibliographic Details
Main Authors: Mehmetcan Gursoy, Behrooz Mirafzal
Format: Article
Language:English
Published: IEEE 2023-01-01
Series:IEEE Access
Subjects:
Online Access:https://ieeexplore.ieee.org/document/10188836/
_version_ 1797771682345123840
author Mehmetcan Gursoy
Behrooz Mirafzal
author_facet Mehmetcan Gursoy
Behrooz Mirafzal
author_sort Mehmetcan Gursoy
collection DOAJ
description This article provides insights into the dynamic performance of indirect and direct control strategies for grid-forming (GFM) inverters. The indirect method for grid-forming inverters utilizes three cascaded stages to produce the reference signal sent to the PWM generator. However, the direct method has only one stage. The indirect method consists of the outer loop, which controls the power, the middle loop, which regulates voltage, and the inner loop, which controls the output current. The direct method does not require the middle and inner control loops. The article compares the performance and sensitivity of both indirect and direct control methods under various conditions, including static, inductive and dynamic loads, by adjusting controller gain parameters. A virtual reactance inrush current mitigation technique is implemented with the direct method to provide momentary control over inrush caused by the dynamic loads. The direct method incorporates a feedforward technique known as virtual reactance inrush current mitigation to outperform the performance of the direct control method in the presence of dynamic and inductive loads. The performance of both control methods is experimentally compared, and the direct method outperforms the indirect method. Experimental analyses are performed in a laboratory-scaled microgrid supplied by a 208V, one 5kVA SiC inverter, and one 10kVA Si-based inverter to compare the performance of the indirect and direct methods under different test scenarios, and the outcomes are presented in this article.
first_indexed 2024-03-12T21:40:07Z
format Article
id doaj.art-169496bd176b449fac88fd062cb3e1cf
institution Directory Open Access Journal
issn 2169-3536
language English
last_indexed 2024-03-12T21:40:07Z
publishDate 2023-01-01
publisher IEEE
record_format Article
series IEEE Access
spelling doaj.art-169496bd176b449fac88fd062cb3e1cf2023-07-26T23:00:41ZengIEEEIEEE Access2169-35362023-01-0111750237503610.1109/ACCESS.2023.329755110188836Direct vs. Indirect Control Schemes for Grid-Forming Inverters–Unveiling a Performance Comparison in a MicrogridMehmetcan Gursoy0https://orcid.org/0000-0003-0986-713XBehrooz Mirafzal1https://orcid.org/0000-0002-6998-1463Department of Electrical and Computer Engineering, Kansas State University, Manhattan, KS, USADepartment of Electrical and Computer Engineering, Kansas State University, Manhattan, KS, USAThis article provides insights into the dynamic performance of indirect and direct control strategies for grid-forming (GFM) inverters. The indirect method for grid-forming inverters utilizes three cascaded stages to produce the reference signal sent to the PWM generator. However, the direct method has only one stage. The indirect method consists of the outer loop, which controls the power, the middle loop, which regulates voltage, and the inner loop, which controls the output current. The direct method does not require the middle and inner control loops. The article compares the performance and sensitivity of both indirect and direct control methods under various conditions, including static, inductive and dynamic loads, by adjusting controller gain parameters. A virtual reactance inrush current mitigation technique is implemented with the direct method to provide momentary control over inrush caused by the dynamic loads. The direct method incorporates a feedforward technique known as virtual reactance inrush current mitigation to outperform the performance of the direct control method in the presence of dynamic and inductive loads. The performance of both control methods is experimentally compared, and the direct method outperforms the indirect method. Experimental analyses are performed in a laboratory-scaled microgrid supplied by a 208V, one 5kVA SiC inverter, and one 10kVA Si-based inverter to compare the performance of the indirect and direct methods under different test scenarios, and the outcomes are presented in this article.https://ieeexplore.ieee.org/document/10188836/Grid-forming invertersislanded microgridfault ride-through
spellingShingle Mehmetcan Gursoy
Behrooz Mirafzal
Direct vs. Indirect Control Schemes for Grid-Forming Inverters–Unveiling a Performance Comparison in a Microgrid
IEEE Access
Grid-forming inverters
islanded microgrid
fault ride-through
title Direct vs. Indirect Control Schemes for Grid-Forming Inverters–Unveiling a Performance Comparison in a Microgrid
title_full Direct vs. Indirect Control Schemes for Grid-Forming Inverters–Unveiling a Performance Comparison in a Microgrid
title_fullStr Direct vs. Indirect Control Schemes for Grid-Forming Inverters–Unveiling a Performance Comparison in a Microgrid
title_full_unstemmed Direct vs. Indirect Control Schemes for Grid-Forming Inverters–Unveiling a Performance Comparison in a Microgrid
title_short Direct vs. Indirect Control Schemes for Grid-Forming Inverters–Unveiling a Performance Comparison in a Microgrid
title_sort direct vs indirect control schemes for grid forming inverters x2013 unveiling a performance comparison in a microgrid
topic Grid-forming inverters
islanded microgrid
fault ride-through
url https://ieeexplore.ieee.org/document/10188836/
work_keys_str_mv AT mehmetcangursoy directvsindirectcontrolschemesforgridforminginvertersx2013unveilingaperformancecomparisoninamicrogrid
AT behroozmirafzal directvsindirectcontrolschemesforgridforminginvertersx2013unveilingaperformancecomparisoninamicrogrid