Comparison of SOGI-FLL with SOGI-PLL for Single-Phase Grid-Connected Inverters

Royan Royan,Trias Andromeda,Mochammad Facta,Hermawan Hermawan,Iwan Setiawan,Hadiyanto Hadiyanto,Budi Warsito Budi Warsito,Maryono Maryono

doi:10.1051/e3sconf/201912514005

Royan Royan, Trias Andromeda + Show 6 more

Open Access

https://doi.org/10.1051/e3sconf/201912514005

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Journal: E3S Web of Conferences	Publication Date: Jan 1, 2019
Citations: 6	License type: CC BY 4.0

Affiliation: Diponegoro University

Abstract

Phase locked loop (PLL) is a feedback system that has a vital role in the grid-connected inverter systems. The primary function of PLL is to obtain various grid information, such as magnitude, frequency, and phase. That used as the basis for the synchronization process. The primary purpose of this paper is to model and compare the performance SOGI-FLL (Second Order Generalized Integrator - Frequency Locked Loop) With SOGI-PLL, which is a relatively standard PLL. Besides that, this paper also aims to investigate the effect of FLL feedback gain on synchronization performance. Based on the simulation results, the performance of SOGI-FLL in its steady state is superior to that of SOGI-PLL especially for the condition of a single phase power systems that change in frequency.

Highlights

Grid Inverters are one of the essential components in renewable power generation that connected to the grid
An essential component in a grid inverter system that is responsible for providing information on magnitude, phase and frequency is Phase locked loop (PLL)
The SOGI-PLL described in the previous section has one major disadvantage, when the input signal frequency is outside the 50Hz power grid operational standard, SOGI output loses tracking accuracy

Summary

Introduction

Grid Inverters are one of the essential components in renewable power generation that connected to the grid. Grid inverters have been widely applied in single phase systems, such as on-grid PV systems [13]. An essential component in a grid inverter system that is responsible for providing information on magnitude, phase and frequency is PLL. The PLL method has advantages in terms of simplicity, and the resulting output is relatively useful for detecting voltage signal parameters, so it is widely applied in inverter components. The main task of the PLL structure is to provide grid parameter references and monitor it, to ensure that the performance of the grid-connected system meets the standard requirements, if the instantaneous voltage on the grid rises or falls, the inverter output voltage must follow.

SOGI-PLL Model

SOGI-FLL Model

Simulation Results and Discussion

The performance of PLL against grid magnitude changes

60 SOGI-PLL

The performance of PLL against grid frequency changes

The influence of FLL feedback amplifiers on synchronization performance

Conclusion