AUTHOR=Wang Qin , Le Lingling , Li Dahu , Ai Xiaomeng , Fang Jiakun , Yao Wei , Wen Jinyu 

TITLE=Modeling and Energy Generation Evaluations of Large-Scale Photovoltaic Plants Equipped With Panel-Level DC Optimizers

JOURNAL=Frontiers in Energy Research

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2022.825994

DOI=10.3389/fenrg.2022.825994

ISSN=2296-598X

ABSTRACT=The distributed maximum power point tracking (DMPPT) technology, based on a DC optimizer (DCO, a DC/DC micro-converter) for each single photovoltaic (PV) panel, is one of the most popular solutions in mitigating the waste of solar energy when suffering mismatch conditions. However, the trade-off between the additional costs of deploying the panel-level power electronic equipment and the improved generation benefits for a large-scale PV plant (LPP) remains to be further studied. This paper presents a static modeling method for the DCO-based distributed LPPs to study the long-term energy generation characteristics based on historical hourly weather data and then evaluate the economic benefits. The operational characteristics of the PV strings equipped with series-connected DCOs for three different topologies (Boost, Buck, and Buck-boost) are investigated, then the control strategies for the PV-DCO generation units are proposed to maximize the energy generation of LPPs under frequent mismatch conditions. Different mismatch scenarios caused by the panel aging, geographical location settings, and partial shading in PV arrays are simulated in the model. Six typical centralized or distributed PV plant configurations are carried out for comparison in case studies, to explore the generation characteristics and the advantages of energy production for the DCO-based distributed LPPs. Besides, the Levelized cost of energy (LCOE) which considers both the energy generation and hardware costs is introduced for the economic evaluation of different structures of LPPs.