A Unified Control Strategy of Distributed Generation for Grid-Connected and Islanded Operation Conditions Using an Artificial Neural Network

Karim M El-Sharawy,Hatem Y Diab,Mahmoud O Abdelsalam,Mostafa I Marei

doi:10.3390/su13116388

Karim M El-Sharawy, Hatem Y Diab + Show 2 more

Open Access

https://doi.org/10.3390/su13116388

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Abstract

This article presents a control strategy that enables both islanded and grid-tied operations of a three-phase inverter in distributed generation. This distributed generation (DG) is based on a dramatically evolved direct current (DC) source. A unified control strategy is introduced to operate the interface in either the isolated or grid-connected modes. The proposed control system is based on the instantaneous tracking of the active power flow in order to achieve current control in the grid-connected mode and retain the stability of the frequency using phase-locked loop (PLL) circuits at the point of common coupling (PCC), in addition to managing the reactive power supplied to the grid. On the other side, the proposed control system is also based on the instantaneous tracking of the voltage to achieve the voltage control in the standalone mode and retain the stability of the frequency by using another circuit including a special equation (wt = 2πft, f = 50 Hz). This utilization provides the ability to obtain voltage stability across the critical load. One benefit of the proposed control strategy is that the design of the controller remains unconverted for other operating conditions. The simulation results are added to evaluate the performance of the proposed control technology using a different method; the first method used basic proportional integration (PI) controllers, and the second method used adaptive proportional integration (PI) controllers, i.e., an Artificial Neural Network (ANN).

Highlights

Centralized power stations all over the world dominate the modern paradigm for power generation and supply
We start from 0 s to 0.4 s and from 0.75 s to 1 s using the C.B condition, which is the certain periodic time that the critical load is supplied by the main grid; during this condition, the phase-locked loop (PLL) is actively connected using the voltage grid, sets the frequency, and is clamped with the grid frequency at 50 HZ as frequency stability; the actual value is tracked to the reference value of the active power at 80 KW, and the reference of the quadrature current is equal to zero; otherwise, the reference of the direct current is a certain value generated from the active power tracking circuit and the voltage load is equal to
A unified control strategy was proposed for three-phase inverter interfacing distributed generation (DG) to operate in both islanded and grid-tied modes

Summary

Introduction

Centralized power stations all over the world dominate the modern paradigm for power generation and supply. The generation of electricity in such plants generally uses as oil, coal, gas and nuclear power. The demand control network between stations and the end user resembles central electricity models. There are a few disadvantages to this single power plant scheme. The operating stresses in the existing transmission and distribution systems emerge from growing loads, which contribute to an increasing burden on electricity networks. Greenhouse gas emissions indicate a need for cleaner renewable energy sources

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Conclusion