Review of Ground Insulation Resistance Detection Methods for Photovoltaic (PV) Systems

Abstract

With the rapid growth of PV systems, accurate detection of insulation resistance in PV inverters has become increasingly crucial to ensure system safety and operational stability. This paper presents a systematic review of current ground insulation resistance detection methods for PV systems. First, the operating principles of various insulation resistance detection schemes are reviewed. Furthermore, the performance of these methods is evaluated based on several key metrics. Additionally, various fault locating techniques are examined. Overall, this paper aims to provide a comprehensive overview of the latest advancements in insulation resistance detection for PV systems.

Keywords

PV system / Insulation resistance / Fault detection / Fault locating

Statement of the Use of Generative AI and AI-Assisted Technologies in the Writing Process

Generative AI was used solely for English grammar polishing.

Acknowledgments

The authors would like to thank the Technical Development Center of Ginlong Technologies Co., Ltd. for their technical assistance and access to the specialized database.

Author Contributions

Conceptualization, W.Z. and L.X.; Methodology, W.Z. and L.X.; Formal Analysis, W.Z.; Investigation, W.Z. and L.X.; Resources, Y.W. (Yiming Wang 1) and P.X.; Data Curation, Y.W. (Yiming Wang 2); Writing—Original Draft Preparation, W.Z. and L.X.; Writing—Review & Editing, W.Z., L.X., Y.W. (Yiming Wang 1), Y.W. (Yiming Wang 2) and K.M.; Visualization, W.Z. and L.X.; Supervision, W.Z., P.X. and K.M.; Project Administration, Y.W. (Yiming Wang 1) and P.X.; Funding Acquisition, Y.W. (Yiming Wang 1).

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data availability is not applicable to this paper as no new data were created or analyzed in this study.

Funding

This work was funded by National Key R&D Program of China (2024YFB3814000) and R&D Program of Zhejiang (2024C01242(SD2)).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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